STOCK TITAN

Old Second Bancorp (NASDAQ: OSBC) Q1 profit climbs amid higher loan losses

Filing Impact
(High)
Filing Sentiment
(Neutral)
Form Type
10-Q

Rhea-AI Filing Summary

Old Second Bancorp reported stronger results for the quarter ended March 31, 2026. Net income rose to $25.6 million from $19.8 million a year earlier, and basic earnings per share increased to $0.49 from $0.44. Net interest and dividend income expanded to $81.1 million from $62.9 million, helped by higher loan and securities income, partly offset by increased deposit and borrowing costs.

Credit costs rose meaningfully: the provision for credit losses climbed to $9.5 million from $2.4 million, and net charge-offs reached $10.8 million, driven by a large charge-off on a downtown Chicago office loan, a warehouse and distribution credit, and higher powersport loan losses. The allowance for credit losses on loans stood at $72.1 million. Total assets were $6.85 billion, with loans of $5.19 billion and deposits of $5.56 billion.

The company continued returning capital, declaring a quarterly dividend of $0.07 per share and repurchasing stock, which increased treasury stock to $26.2 million. After quarter-end, it redeemed $30.0 million of subordinated debt as it transitioned from a fixed to a SOFR-based floating rate.

Positive

  • Stronger earnings and EPS growth: Q1 2026 net income increased to $25.6 million from $19.8 million, with basic EPS up to $0.49 from $0.44, supported by higher net interest and noninterest income.

Negative

  • Materially higher credit losses: Provision for credit losses rose to $9.5 million from $2.4 million and net charge-offs reached $10.8 million, including a $3.9 million office loan charge-off and elevated powersport loan losses.

Insights

Profitability improved, but credit costs and charge-offs rose sharply.

Old Second Bancorp grew quarterly net income to $25.6M from $19.8M, with basic EPS up to $0.49. Net interest and dividend income increased to $81.1M, reflecting higher loan yields and a larger balance sheet after the Bancorp Financial acquisition.

That growth came with much higher credit costs. Provision for credit losses jumped to $9.5M versus $2.4M, and net charge-offs rose to $10.8M. Management attributes this mainly to a $3.9M charge-off on a downtown Chicago office property, a $1.3M commercial warehouse credit, and elevated powersport loan losses, while the allowance for credit losses on loans held at $72.1M.

Capital actions were active: the company paid a $0.07 per‑share dividend and repurchased shares, raising treasury stock to $26.2M. A post‑quarter redemption of $30.0M of subordinated debt reduces future interest on now‑floating debt, though the net effect will be clearer in subsequent quarters’ results.

Net income $25.6M Three months ended March 31, 2026
Basic EPS $0.49 Three months ended March 31, 2026
Net interest and dividend income $81.1M Three months ended March 31, 2026
Provision for credit losses $9.5M Three months ended March 31, 2026
Net charge-offs $10.8M Three months ended March 31, 2026
Allowance for credit losses on loans $72.1M Balance at March 31, 2026
Total assets $6.85B Balance at March 31, 2026
Quarterly dividend per share $0.07 Declared for common stock in Q1 2026
allowance for credit losses financial
"At March 31, 2026, our allowance for credit losses (“ACL”) on loans totaled $72.1 million"
Allowance for credit losses is a reserve set aside by a financial institution to cover potential losses from borrowers who may not repay their loans. It acts like a safety net, helping the institution prepare for loans that might turn sour. For investors, it signals how cautious the institution is about the quality of its loans and potential risks to its financial health.
purchased credit deteriorated financial
"Purchased loans and leases that reflect a more-than-insignificant deterioration of credit from origination are considered purchased credit deteriorated (“PCD”) loans."
Purchased credit deteriorated (PCD) describes a debt asset bought when its borrower’s ability to repay has already worsened since the loan was first issued. Under accounting rules, buyers must immediately account for the full expected loss rather than spreading it out, so PCD holdings lower reported earnings and capital right away and signal higher credit risk—similar to buying a used car with known damage that you must account for in your budget.
nonaccrual loans financial
"The table presents all nonaccrual loans as of March 31, 2026, and December 31, 2025"
Nonaccrual loans are loans a lender has stopped counting toward interest income because the borrower is overdue or unlikely to pay; the lender only records cash payments received and may set aside extra funds to cover potential losses. For investors, a rising number or amount of nonaccrual loans signals weaker credit quality, lower future interest revenue and larger potential write-downs — similar to pausing expected subscription income when many customers stop paying.
collateral dependent loans financial
"Generally, the Bank considers a loan to be collateral dependent when, based on current information and events, it is probable that foreclosure could be initiated."
Federal Home Loan Bank Chicago (FHLBC) stock financial
"FHLBC stock was recorded at $10.6 million as of March 31, 2026, and $11.3 million as of December 31, 2025."
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Table of Contents

I

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-Q

QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF

THE SECURITIES EXCHANGE ACT OF 1934

For the quarterly period ended March 31, 2026

OR

TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE

SECURITIES EXCHANGE ACT OF 1934

For transition period from          to          

Commission File Number 000-10537

Graphic

(Exact name of Registrant as specified in its charter)

Delaware

36-3143493

(State or other jurisdiction

(I.R.S. Employer Identification Number)

of incorporation or organization)

37 South River Street, AuroraIllinois     60507

(Address of principal executive offices) (Zip Code)

(630) 892-0202

(Registrant’s telephone number, including area code)

Not applicable

(Former name, former address and former fiscal year, if changed since last report)

Securities registered pursuant to Section 12(b) of the Act:

Title of each class

Trading Symbol(s)

Name of each exchange on which registered

Common Stock

OSBC

The Nasdaq Stock Market

Indicate by check mark whether the Registrant (1) has filed all reports required to be filed by Section 13 or 15-(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the Registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.

Yes         No 

Indicate by check mark whether the Registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the Registrant was required to submit and post such files). Yes  No 

Indicate by check mark whether the Registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, smaller reporting company, or an emerging growth company. See the definitions of ‘‘large accelerated filer,’’ ‘‘accelerated filer,’’ ‘‘smaller reporting company,’’ and ‘‘emerging growth company’’ in Rule 12b–2 of the Exchange Act.

Large accelerated filerAccelerated filer

Non-accelerated filerSmaller reporting companyEmerging growth company

If an emerging growth company, indicate by check mark if the Registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.

Indicate by check mark whether the Registrant is a shell company (as defined in Exchange Act Rule 12b-2).

Yes         No 

As of May 5, 2026, the Registrant has 51,432,372 shares of common stock outstanding at $1.00 par value per share.

Table of Contents

OLD SECOND BANCORP, INC.

Form 10-Q Quarterly Report

Table of Contents

Cautionary Note Regarding Forward-Looking Statements

PART I

Page Number

Item 1.

Financial Statements

5

Item 2.

Management’s Discussion and Analysis of Financial Condition and Results of Operations

42

Item 3.

Quantitative and Qualitative Disclosures about Market Risk

61

Item 4.

Controls and Procedures

62

PART II

Item 1.

Legal Proceedings

63

Item 1A.

Risk Factors

63

Item 2.

Unregistered Sales of Equity Securities and Use of Proceeds

63

Item 3.

Defaults Upon Senior Securities

63

Item 4.

Mine Safety Disclosures

64

Item 5.

Other Information

64

Item 6.

Exhibits

65

Signatures

66

2

Table of Contents

CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS

This report and other publicly available documents of Old Second Bancorp, Inc. (“Old Second” or the “Company”) contain forward-looking statements within the meaning of the Private Securities Litigation Reform Act, including, but not limited to, management’s expectations regarding future plans, strategies and financial performance, including regulatory developments, industry and economic trends and estimates and assumptions underlying accounting policies. Forward-looking statements are based on our current beliefs, expectations, assumptions, and on information currently available and may be identified by the use of words such as “expects,” “intends,” “believes,” “may,” “will,” “would,” “could,” “should,” “plan,” “anticipate,” “estimate,” “forecasts,” “possible,” “implies,” “likely” or the negative thereof as well as other similar words and expressions of the future.  Forward-looking statements are subject to risks, uncertainties and assumptions that are difficult to predict as to timing, extent, likelihood and degree of occurrence, which could cause our actual results to differ materially from those anticipated in or by such statements. Potential risks and uncertainties include, but are not limited to, the following:

our ability to execute our growth strategy;
negative economic conditions that adversely affect the economy, real estate values, the job market and other factors nationally and in our market area, in each case that may affect our liquidity and the performance of our loan portfolio;
risks with respect to our ability to successfully expand and integrate businesses and operations that we acquire, as well as our ability to identify and complete future mergers or acquisitions;
the financial success and viability of the borrowers of our commercial loans;
changes in U.S. monetary policy, the level and volatility of interest rates, the capital markets and other market conditions that may affect, among other things, our liquidity and the value of our assets and liabilities;
competitive pressures from other financial service businesses and from nontraditional financial technology (“FinTech”) companies;
any negative perception of our reputation or financial strength;
our ability to raise additional capital on acceptable terms when needed;
our ability to raise cost-effective funding to support business plans when needed;
our ability to use technology to provide products and services that will satisfy customer demands and create efficiencies in operations;
adverse effects on our information technology systems resulting from system failures, human error or cyberattacks;
risks associated with data privacy laws and regulations;
risks associated with the development and use of artificial intelligence (“AI”);
adverse effects of cyberattacks or failures by our vendors to provide agreed upon services in the manner and at the cost agreed, particularly our information technology vendors and those vendors performing a service on our behalf;
the impact of any claims or legal actions, including any effect on our reputation;
losses incurred in connection with repurchases and indemnification payments related to mortgages;
the soundness of other financial institutions and other counter-party risk;
changes in accounting standards, rules and interpretations and the related impact on our financial statements;
our ability to receive dividends from our subsidiaries;
a decrease in our regulatory capital ratios or negative changes in our capital position;
adverse federal or state tax assessments, or changes in tax laws or policies;
risks associated with actual or potential litigation or investigations by customers, regulatory agencies or others;
legislative or regulatory changes, particularly changes in regulation of financial services companies;
increased costs of compliance, heightened regulatory capital requirements and other risks associated with changes in regulation and the current regulatory environment;
risks associated with complex and changing regulatory environments, including, among others, with respect to data privacy, artificial intelligence, information security, climate change or other environmental, social and governance matters, and labor matters, relating to our operations;
changes in political and economic conditions, including potential disruptions resulting from U.S. federal government funding lapses, shutdowns, or related fiscal policy uncertainty;
the adverse effects of events beyond our control that may have a destabilizing effect on financial markets and the economy, such as epidemics and pandemics, war or terrorist activities, such as the war in Ukraine, the war in Iran, and the conflict between China and Taiwan, essential utility outages, deterioration in the global economy, instability in the credit markets, disruptions in our customers’ supply chains or disruption in transportation;
changes in trade policy and any related tariffs; and

3

Table of Contents

each of the factors and risks under the heading “Risk Factors” in our 2025 Annual Report on Form 10-K and in subsequent filings we make with the SEC.

Because our ability to predict results or the actual effect of future plans or strategies is inherently uncertain, there can be no assurances that future actual results will correspond to any forward-looking statements, and you should not rely on any forward-looking statements. Additionally, all statements in this Form 10-Q, including forward-looking statements, speak only as of the date they are made, and we undertake no obligation to update any statement in light of new information or future events, except as required by applicable law.

4

Table of Contents

PART I – FINANCIAL INFORMATION

Item 1. Financial Statements

Old Second Bancorp, Inc. and Subsidiaries

Consolidated Balance Sheets

(In thousands, except share data)

(unaudited)

March 31, 

December 31, 

  ​ ​ ​

2026

  ​ ​ ​

2025

Assets

Cash and due from banks

$

48,100

$

51,665

Interest earning deposits with financial institutions

67,627

72,360

Cash and cash equivalents

115,727

124,025

Securities available-for-sale, at fair value

1,115,443

1,090,523

Federal Home Loan Bank Chicago (“FHLBC”) and Federal Reserve Bank Chicago (“FRBC”) stock

31,350

32,025

Loans held-for-sale

4,344

3,645

Loans

5,185,237

5,252,131

Less: allowance for credit losses on loans

72,126

72,301

Net loans

5,113,111

5,179,830

Premises and equipment, net

85,634

86,645

Other real estate owned, net

632

1,427

Mortgage servicing rights, at fair value

9,579

9,459

Goodwill

129,196

129,196

Core deposit intangible ("CDI")

22,516

23,692

Bank-owned life insurance (“BOLI”)

131,563

130,481

Deferred tax assets, net

31,321

31,276

Other assets

58,805

60,451

Total assets

$

6,849,221

$

6,902,675

Liabilities

Deposits:

Noninterest bearing demand

$

1,755,548

$

1,739,117

Interest bearing:

Savings, NOW, and money market

2,795,038

2,745,540

Time

1,014,413

1,111,412

Total deposits

5,564,999

5,596,069

Securities sold under repurchase agreements

23,130

23,769

Other short-term borrowings

200,000

215,000

Junior subordinated debentures

25,774

25,774

Subordinated debentures

59,574

59,552

Notes payable and other borrowings

14,837

14,825

Other liabilities

67,610

70,918

Total liabilities

5,955,924

6,005,907

Stockholders’ Equity

Common stock

53,015

53,015

Additional paid-in capital

338,418

341,451

Retained earnings

559,129

537,231

Accumulated other comprehensive loss, net

(31,095)

(28,738)

Treasury stock

(26,170)

(6,191)

Total stockholders’ equity

893,297

896,768

Total liabilities and stockholders’ equity

$

6,849,221

$

6,902,675

March 31, 2026

December 31, 2025

Common

Common

Stock

  ​ ​ ​

Stock

Par value

$

1.00

$

1.00

Shares authorized

120,000,000

120,000,000

Shares issued

53,015,496

53,015,496

Shares outstanding

51,665,659

52,669,224

Treasury shares

1,349,837

346,272

See accompanying notes to consolidated financial statements.

5

Table of Contents

Old Second Bancorp, Inc. and Subsidiaries

Consolidated Statements of Income

(In thousands, except per share data)

(unaudited)

Three Months Ended March 31, 

  ​ ​ ​

2026

  ​ ​ ​

2025

  ​ ​ ​

Interest and dividend income

Loans, including fees

$

87,138

$

61,595

Loans held-for-sale

43

22

Securities:

Taxable

8,949

9,227

Tax exempt

1,155

1,260

Dividends from FHLBC and FRBC stock

512

473

Interest bearing deposits with financial institutions

549

988

Total interest and dividend income

98,346

73,565

Interest expense

Savings, NOW, and money market deposits

7,147

4,913

Time deposits

7,217

4,829

Securities sold under repurchase agreements

50

68

Other short-term borrowings

1,791

17

Junior subordinated debentures

296

288

Subordinated debentures

546

546

Notes payable and other borrowings

155

-

Total interest expense

17,202

10,661

Net interest and dividend income

81,144

62,904

Provision for credit losses

9,500

2,400

Net interest and dividend income after provision for credit losses

71,644

60,504

Noninterest income

Wealth management

3,383

3,089

Service charges on deposits

3,126

2,976

Secondary mortgage fees

121

73

Mortgage servicing rights mark to market loss

(152)

(570)

Mortgage servicing income

497

480

Net gain on sales of mortgage loans

555

464

Change in cash surrender value of BOLI

1,082

498

Card related income

2,354

2,241

Other income

1,664

950

Total noninterest income

12,630

10,201

Noninterest expense

Salaries and employee benefits

29,673

26,993

Occupancy, furniture and equipment

5,371

4,548

Computer and data processing

3,375

2,348

FDIC insurance

759

628

Net teller & bill paying

716

658

General bank insurance

353

330

Amortization of core deposit intangible

1,176

1,037

Advertising and marketing expense

551

229

Card related expense

1,519

1,380

Professional fees

1,299

1,095

Consumer credit expense

1,522

25

Other real estate expense, net

(186)

1,873

Other expense

4,082

3,361

Total noninterest expense

50,210

44,505

Income before income taxes

34,064

26,200

Provision for income taxes

8,479

6,370

Net income

$

25,585

$

19,830

Basic earnings per share

$

0.49

$

0.44

Diluted earnings per share

0.48

0.43

Dividends declared per share

0.07

0.06

See accompanying notes to consolidated financial statements.

6

Table of Contents

Old Second Bancorp, Inc. and Subsidiaries

Consolidated Statements of Comprehensive Income

(In thousands)

(unaudited)

Three Months Ended March 31, 

  ​ ​ ​

2026

  ​ ​ ​

2025

  ​ ​ ​

Net Income

$

25,585

$

19,830

Unrealized holding (losses) gains on available-for-sale securities arising during the period

(3,287)

8,931

Related tax benefit (expense)

920

(2,501)

Holding (losses) gains, after tax, on available-for-sale securities

(2,367)

6,430

Less: Reclassification adjustment for the net gains realized during the period

Net realized gains (losses)

-

-

Related tax (expense) benefit

-

-

Net realized gains (losses) after tax

-

-

Other comprehensive (loss) income on available-for-sale securities

(2,367)

6,430

Changes in fair value of derivatives used for cash flow hedges

12

(85)

Related tax (expense) benefit

(2)

24

Other comprehensive income (loss) on cash flow hedges

10

(61)

Total other comprehensive (loss) income

(2,357)

6,369

Total comprehensive income

$

23,228

$

26,199

Accumulated

Accumulated

Total

Unrealized Gain

Unrealized Gain

Accumulated Other

(Loss) on Securities

(Loss) on Derivative

Comprehensive

(unaudited)

Available-for -Sale

Instruments

Income/(Loss)

For the Three Months Ended

Balance, January 1, 2025

$

(49,412)

$

1,664

$

(47,748)

Other comprehensive income (loss), net of tax

6,430

(61)

6,369

Balance, March 31, 2025

$

(42,982)

$

1,603

$

(41,379)

Balance, January 1, 2026

$

(31,010)

$

2,272

$

(28,738)

Other comprehensive (loss) income, net of tax

(2,367)

10

(2,357)

Balance, March 31, 2026

$

(33,377)

$

2,282

$

(31,095)

See accompanying notes to consolidated financial statements.

7

Table of Contents

Old Second Bancorp, Inc. and Subsidiaries

Consolidated Statements of Cash Flows

(In thousands)

(unaudited)

Three Months Ended March 31, 

2026

  ​ ​ ​

2025

Cash flows from operating activities

Net income

$

25,585

$

19,830

Adjustments to reconcile net income to net cash provided by operating activities:

Net premium / discount amortization on securities

475

457

Provision for credit losses

9,500

2,400

Originations of loans held-for-sale

(22,950)

(14,371)

Proceeds from sales of loans held-for-sale

22,525

12,115

Net gains on sales of mortgage loans

(555)

(464)

Mortgage servicing rights mark to market loss

152

570

Net accretion of purchase accounting adjustments and other discounts on loans

(175)

(179)

Net change in cash surrender value of BOLI

(1,082)

(498)

Net (gains) losses on sale of other real estate owned

(98)

236

Provision for other real estate owned valuation losses

-

454

Depreciation of fixed assets and amortization of leasehold improvements

1,698

1,408

Change in operating lease right-of-use asset

(512)

261

Amortization of core deposit intangibles

1,176

1,037

Change in current income taxes

7,114

5,797

Deferred tax expense

871

2,935

Change in accrued interest receivable and other assets

2,187

1,171

Accretion of purchase accounting adjustment on time deposits

(25)

(274)

Change in accrued interest payable and other liabilities

(10,991)

(15,989)

Change in operating lease payable

602

(441)

Stock based compensation

1,442

1,383

Net cash provided by operating activities

36,939

17,838

Cash flows from investing activities

Proceeds from maturities and calls, including pay down of securities available-for-sale

78,204

106,329

Purchases of securities available-for-sale

(106,886)

(82,875)

Net redemptions of FHLBC/FRBC stock

675

-

Net change in loans

56,762

36,815

Proceeds from sales of other real estate owned, net of participations

1,525

18,049

Proceeds from disposition of premises and equipment

76

-

Net purchases of premises and equipment

(769)

(1,609)

Cash received from acquisition, net

-

28

Net cash provided by investing activities

29,587

76,737

Cash flows from financing activities

Net change in deposits

(31,045)

84,334

Net change in securities sold under repurchase agreements

(639)

2,007

Net change in other short-term borrowings

(15,000)

(20,000)

Dividends paid on common stock

(3,686)

(2,694)

Purchase of treasury stock

(24,454)

(1,430)

Net cash (used in) provided by financing activities

(74,824)

62,217

Net change in cash and cash equivalents

(8,298)

156,792

Cash and cash equivalents at beginning of period

124,025

99,329

Cash and cash equivalents at end of period

$

115,727

$

256,121

See accompanying notes to consolidated financial statements.

8

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Old Second Bancorp, Inc. and Subsidiaries

Consolidated Statements of Changes in

Stockholders’ Equity

(In thousands, except share data)

Accumulated

Number of

Additional

Other

Total

(unaudited)

Common Shares

Common

Paid-In

Retained

Comprehensive

Treasury

Stockholders’

  ​ ​ ​

Outstanding

Stock

  ​ ​ ​

Capital

  ​ ​ ​

Earnings

  ​ ​ ​

(Loss) Income

  ​ ​ ​

Stock

  ​ ​ ​

Equity

For the Three Months Ended

Balance, January 1, 2025

44,873,467

$

44,908

$

205,284

$

469,165

$

(47,748)

$

(575)

$

671,034

Net income

19,830

19,830

Other comprehensive income, net of tax

6,369

6,369

Dividends declared on common stock, ($0.06 per share)

(2,695)

(2,695)

Vesting of restricted stock

252,615

186

(1,385)

1,199

-

Stock based compensation

1,383

1,383

Purchase of treasury stock from taxes withheld on stock awards

(78,931)

(1,430)

(1,430)

Balance, March 31, 2025

45,047,151

$

45,094

$

205,282

$

486,300

$

(41,379)

$

(806)

$

694,491

Balance, January 1, 2026

52,669,224

$

53,015

$

341,451

$

537,231

$

(28,738)

$

(6,191)

$

896,768

Net income

25,585

25,585

Other comprehensive loss, net of tax

(2,357)

(2,357)

Dividends declared on common stock, ($0.07 per share)

(3,687)

(3,687)

Vesting of restricted stock

239,652

(4,475)

4,475

-

Stock based compensation

1,442

1,442

Purchase of treasury stock from taxes withheld on stock awards

(67,358)

(1,368)

(1,368)

Purchase of treasury stock from stock repurchase program

(1,175,859)

(23,086)

(23,086)

Balance, March 31, 2026

51,665,659

$

53,015

$

338,418

$

559,129

$

(31,095)

$

(26,170)

$

893,297

9

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Old Second Bancorp, Inc. and Subsidiaries

Notes to Consolidated Financial Statements

(Dollar amounts in thousands, except per share data, unaudited)

Note 1 – Basis of Presentation and Changes in Significant Accounting Policies

The accounting policies followed in the preparation of the interim consolidated financial statements are consistent with those used in the preparation of the annual financial information. The interim consolidated financial statements reflect all normal and recurring adjustments that are necessary, in the opinion of management, for a fair statement of results for the interim period presented. Results for the period ended March 31, 2026, are not necessarily indicative of the results that may be expected for the year ending December 31, 2026. These interim consolidated financial statements and accompanying notes are unaudited and should be read in conjunction with the audited financial statements and notes included in Old Second Bancorp, Inc.’s (the “Company”) annual report on Form 10-K for the year ended December 31, 2025. Unless otherwise indicated, dollar amounts in the tables contained in the notes to the consolidated financial statements are in thousands. Certain items in prior periods have been reclassified to conform to the current presentation.

The Company’s consolidated financial statements are prepared in accordance with United States generally accepted accounting principles (“GAAP”) and follow general practices within the banking industry. Application of these principles requires management to make estimates, assumptions, and judgments that affect the amounts reported in the consolidated financial statements and accompanying notes. These estimates, assumptions, and judgments are based on information available as of the date of the consolidated financial statements. Future changes in information may affect these estimates, assumptions, and judgments, which, in turn, may affect amounts reported in the consolidated financial statements.

Recent Accounting Pronouncements

The following is a summary of recent accounting pronouncements that have impacted or could potentially affect the Company:  

ASU 2023-06 – On October 9, 2023, the FASB issued ASU 2023-06 “Disclosure Improvements: Codification Amendments in Response to the SEC’s Disclosure Update and Simplification Initiative.” The amendments in the ASU modify the disclosure or presentation requirements of a variety of topics in the codification. Certain of the amendments represent clarifications to, or technical corrections of, the current requirements. Each amendment in the ASU will only become effective if the SEC removes the related disclosure or presentation requirement from its existing regulations by June 30, 2027. The amendments in this ASU are not expected to have a material impact on the financial statements of the Company.

ASU 2024-03 – On November 4, 2024, the FASB issued ASU 2024-03 “Income Statement—Reporting Comprehensive Income—Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses.” This ASU requires public companies to disclose, in the notes to financial statements, specified information about certain costs and expenses at each interim and annual reporting period. Specifically, they will be required to: (1) Disclose the amounts of (a) purchases of inventory; (b) employee compensation; (c) depreciation; (d) intangible asset amortization; and (e) depreciation, depletion, and amortization recognized as part of oil- and gas-producing activities (or other amounts of depletion expense) included in each relevant expense caption. (2) Include certain amounts that are already required to be disclosed under current generally accepted accounting principles (GAAP) in the same disclosure as the other disaggregation requirements. (3) Disclose a qualitative description of the amounts remaining in relevant expense captions that are not separately disaggregated quantitatively. (4) Disclose the total amount of selling expenses and, in annual reporting periods, an entity’s definition of selling expenses. ASU 2024-03 is effective for public business entities for annual reporting periods beginning after December 15, 2026, and interim reporting periods beginning after December 15, 2027, and is not expected to have a material impact on the financial statements of the Company.  

ASU 2025-01On January 6, 2025, the FASB issued ASU 2025-01 “Income Statement—Reporting Comprehensive Income—Expense Disaggregation Disclosures (Subtopic 220-40): Clarifying the Effective Date.” ASU 2024-03 is effective for public business entities for annual reporting periods beginning after December 15, 2026, and interim reporting periods within annual reporting periods beginning after December 15, 2027, which dates were clarified in ASU 2025-01, and is not expected to have a material impact on the financial statements of the Company.

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ASU 2025-03On May 12, 2025, the FASB issued ASU 2025-03 “Business Combinations (Topic 805) and Consolidation (Topic 810): Determining the Accounting Acquirer in the Acquisition of a Variable Interest Entity.” This ASU revises current guidance for determining the accounting acquirer for a transaction effected primarily by exchanging equity interests in which the legal acquiree is a variable interest entity that meets the definition of a business. The amendments require an entity to consider the same factors that are currently required for determining which entity is the accounting acquirer in other acquisition transactions. This ASU is effective for annual reporting periods beginning after December 15, 2026, and interim reporting periods within those annual reporting periods. Early adoption is permitted in an interim or annual reporting period in which financial statements have not yet been issued (or made available for issuance). If an entity adopts ASU No. 2025-03 in an interim reporting period, it should adopt it as of the beginning of that interim reporting period or the beginning of the annual reporting period that includes that interim reporting period. An entity should apply ASU 2025-03 on a prospective basis to all business combinations that have an acquisition date that occurs on or after the date of initial application of ASU 2025-03. ASU 2025-03 is not expected to have a material impact on the financial statements of the Company.

ASU 2025-08On November 12, 2025, the FASB issued ASU 2025-08 “'Financial Instruments—Credit Losses (Topic 326): Purchased Loans.” This ASU expands the population of acquired financial assets accounted for using the gross-up approach. Acquired loans (excluding credit cards) are deemed purchased seasoned loans and accounted for using the gross-up approach upon acquisition if criteria established by the new guidance are met. This change aims to enhance comparability, consistency, and better reflect the economics of acquiring financial assets. ASU 2025-08 is effective for interim and annual periods in fiscal years beginning after December 15, 2026, and is applied prospectively. Early adoption is permitted.

Old Second has elected not to early adopt ASU 2025-08 at this time. When adopted, the standard will be adopted prospectively; thus, the accounting for previously completed business combinations will not be impacted. However, adopting this accounting standard is anticipated to have a material impact on the accounting for purchased loans on any business combination completed after adoption.

ASU 2025-11On December 8, 2025, the FASB issued ASU 2025-11 “Interim Reporting (Topic 270): Narrow-Scope Improvements”: This ASU does not change the fundamental nature of interim reporting or expand or reduce current interim disclosure requirements. The amendments in this ASU: i) clarify that the guidance in Topic 270 applies to all entities that provide interim financial statements and notes in accordance with GAAP; ii) create a comprehensive list in FASB ASC Topic 270 of interim disclosures that are required in interim financial statements and notes in accordance with GAAP; iii) incorporate a disclosure principle, which is modeled after previous SEC guidance, that requires entities to disclose events and changes that occur after the end of the most recent fiscal year that have a material impact on the entity; and iv) improve guidance about information included in and the format of interim financial statements. The amendments in this ASU are effective for public business entities for interim periods within annual periods beginning after December 15, 2027. ASU 2025-11 is not expected to have a material impact on the financial statements of the Company.

ASU 2025-12On December 17, 2025, the FASB issued ASU 2025-12 “Codification Improvements”: The amendments in this ASU update the FASB ASC for a broad range of Topics arising from technical corrections, unintended application of the Codification, clarifications, and other minor improvements. The amendments in the ASU, which addresses 33 issues, affect a wide variety of Topics in the Codification and apply to all reporting entities within the scope of the affected accounting guidance. The amendments in this ASU are effective for all entities for annual periods beginning after December 15, 2026, and interim periods within those annual periods. Early adoption is permitted in both interim and annual periods in which financial statements have not yet been issued or made available for issuance. ASU 2025-12 is not expected to have a material impact on the financial statements of the Company.

Changes in Significant Accounting Policies

Significant accounting policies are presented in Note 1 to the consolidated financial statements included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2025. These policies, along with the disclosures presented in the other financial statement notes and, in this discussion, provide information on how significant assets and liabilities are valued in the consolidated financial statements and how those values are determined. During the first quarter of 2026, the Company had no changes to significant accounting policies or estimates.

Subsequent Events

Redemption of Debt

On April 15, 2026, we redeemed $30.0 million of the total $60.0 million subordinated debt held, which was the same date this debt changed from a 3.50% fixed rate to Three-Month Term Secured Overnight Financing Rate (“SOFR”) plus 273 basis points, payable quarterly in arrears.  

Dividends

On April 21, 2026, our Board of Directors declared a cash dividend of $0.07 per share of common stock payable on May 11, 2026, to stockholders of record as of May 1, 2026; dividends of $3.6 million will be paid to stockholders on May 11, 2026.

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Note 2 – Acquisition

Completed Acquisitions

Bancorp Financial

On July 1, 2025, the Company completed its acquisition of Bancorp Financial and its wholly-owned subsidiary, Evergreen Bank Group, based in Oakbrook, Illinois, with operations throughout our existing market footprint as well as a loan production office in Reno, Nevada.  This acquisition brought increased scale and new markets to the Company, and provided new product offerings and line of business opportunities.  At closing, the Company acquired $1.43 billion of assets, $1.20 billion of loans, $119.1 million of securities, and $1.23 billion of deposits, net of fair value adjustments. Under the terms of the merger agreement, each outstanding share of Bancorp Financial common stock was exchanged for 2.5814 shares of the Company’s common stock, plus $15.93 of cash. This resulted in merger consideration of $189.4 million, based on the closing price of the Company’s common stock on the date of acquisition, which consisted of 7.9 million shares of the Company’s common stock and $48.9 million of cash.  Goodwill of $36.0 million associated with the acquisition was recorded by the Company, which was the result of expected synergies, operational efficiencies and other factors.

The acquisition of Bancorp Financial has been accounted for as a business combination. The Company recorded the estimate of fair value based on initial valuations available at July 1, 2025. The determination of estimated fair value required management to make assumptions related to discount rates, expected future cash flows, market conditions and other future events that are often subjective in nature and may require adjustments, which can be subject to adjustment for additional information received during the measurement period which cannot extend beyond July 1, 2026.  None of the $36.0 million of goodwill recorded is expected to be deductible for income tax purposes.

As permitted by ASC No. 805-10-25, Business Combinations, the above estimated amounts may be adjusted up to one year after the closing date of the transaction to reflect any new information obtained about facts and circumstances existing at the acquisition date. While the Bank believes that the information available on the merger date provided a reasonable basis for estimating fair value, additional information and evidence may be provided which will be utilized to finalize all valuations and record final adjustments during the one year subsequent measurement period. These adjustments may include: (i) changes in deferred tax assets or liabilities related to fair value estimates and changes in the expected realization of items considered to be net operating loss carryforwards due to tax calculations still in process, (ii) immaterial changes in loan valuations, and (iii) changes in goodwill as a result of the net effect of any adjustments. As such, any changes in the estimated fair value of assets, including acquired loans, will be recognized in the period the adjustment is identified.

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The following table provides the purchase price allocation as of the July 1, 2025 acquisition of Bancorp Financial for the assets acquired and liabilities assumed at their estimated fair values as of the purchase date, as recorded by the Company:

Bancorp Financial Transaction Summary

As of Date of Transaction

July 1, 2025

Assets

Cash and due from banks

$

59,385

Securities available-for-sale and held-to-maturity, at fair value

119,117

FHLBC stock

1,958

Loans, net of purchase accounting adjustments

1,195,739

Premises and equipment

2,513

Core deposit intangible

6,206

Bank-owned life insurance ("BOLI")

13,916

Deferred tax assets

13,642

Other assets

14,764

Total assets

$

1,427,240

Liabilities

Noninterest bearing demand

$

73,744

Interest bearing deposits

1,158,778

Total deposits

1,232,522

Short-term borrowings

15,500

Long-term debt

14,800

Deferred tax liabilities

-

Other liabilities

10,978

Total liabilities

1,273,800

Cash consideration paid

48,884

Stock issued for acquisition

140,520

Total consideration

189,404

Total liabilities assumed and cash consideration received for transaction

$

1,463,204

Goodwill

$

35,964

Expenses related to the Bancorp Financial acquisition totaled $349,000 and $278,000 for the quarters ended March 31, 2026 and 2025, respectively. The expenses related to the acquisition are reported within noninterest expense based on the line items impacted, which are primarily salaries and employee benefits, occupancy, furniture and equipment, computer and data processing, legal fees, and other expense in the Consolidated Statements of Income.

Purchased loans and leases that reflect a more-than-insignificant deterioration of credit from origination are considered purchased credit deteriorated (“PCD”) loans. For PCD loans, the initial estimate of expected credit losses was recognized in the allowance for credit losses (“ACL”) on the date of acquisition using the same methodology as other loans and leases held-for-investment. The following table provides a summary of loans purchased as part of the Bancorp Financial acquisition which were individually evaluated and determined to be PCD loans at acquisition.

As of

Bancorp Financial Acquired PCD Loans

July 1, 2025

Par value of acquired loans

$

89,870

Allowance for credit losses

(17,540)

Non-credit premium

722

Purchase price of PCD loans at acquisition

$

73,052

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Note 3 – Securities

Our investment portfolio serves the liquidity needs and income objectives of the Company. While the portfolio serves as an important component of the overall liquidity management at the Bank, portions of the portfolio also serve as income producing assets. The size and composition of the portfolio reflects liquidity needs, loan demand and interest income objectives. Portfolio size and composition will be adjusted from time to time. While a significant portion of the portfolio consists of readily marketable securities to address liquidity, other parts of the portfolio may reflect funds invested pending future loan demand or to maximize interest income without undue interest rate risk.

Investments are comprised of debt securities and non-marketable equity investments. Securities available-for-sale are carried at fair value. Unrealized gains and losses, net of tax, on securities available-for-sale are reported as a separate component of equity. This balance sheet component changes as interest rates and market conditions change. Unrealized gains and losses are not included in the calculation of regulatory capital.

Federal Home Loan Bank of Chicago (“FHLBC”) and Federal Reserve Bank of Chicago (“FRBC”) stock are considered non-marketable equity investments. FHLBC stock was recorded at $10.6 million as of March 31, 2026, and $11.3 million as of December 31, 2025. FRBC stock was recorded at $20.7 million at March 31, 2026 and December 31, 2025. Our FHLBC stock is necessary to maintain access to FHLBC advances.

The following tables summarize the amortized cost and fair value of the securities portfolio at March 31, 2026, and December 31, 2025, and the corresponding amounts of gross unrealized gains and losses:

Gross

Gross

Amortized

Unrealized

Unrealized

Fair

March 31, 2026

  ​ ​ ​

Cost1

  ​ ​ ​

Gains

  ​ ​ ​

Losses

Value

Securities available-for-sale

U.S. Treasury

$

164,232

$

754

$

-

$

164,986

U.S. government agencies

68,949

-

(324)

68,625

U.S. government agencies mortgage-backed

92,318

21

(7,129)

85,210

States and political subdivisions

211,216

269

(8,141)

203,344

Collateralized mortgage obligations

394,111

705

(31,485)

363,331

Asset-backed securities

45,318

469

(1,282)

44,505

Collateralized loan obligations

184,941

24

(254)

184,711

Equity securities

714

17

-

731

Total securities available-for-sale

$

1,161,799

$

2,259

$

(48,615)

$

1,115,443

Gross

Gross

Amortized

Unrealized

Unrealized

Fair

December 31, 2025

  ​ ​ ​

Cost1

  ​ ​ ​

Gains

  ​ ​ ​

Losses

Value

Securities available-for-sale

U.S. Treasury

$

164,296

$

1,564

$

-

$

165,860

U.S. government agencies

29,421

-

(245)

29,176

U.S. government agencies mortgage-backed

95,899

-

(7,119)

88,780

States and political subdivisions

213,366

450

(7,441)

206,375

Collateralized mortgage obligations

388,774

1,102

(30,571)

359,305

Asset-backed securities

46,600

423

(1,207)

45,816

Collateralized loan obligations

194,552

151

(239)

194,464

Equity securities

684

63

-

747

Total securities available-for-sale

$

1,133,592

$

3,753

$

(46,822)

$

1,090,523

1 Excludes accrued interest receivable of $6.4 million at March 31, 2026, and $6.9 million at December 31, 2025, that is recorded in other assets on the Consolidated Balance Sheets.

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The fair value, amortized cost and weighted average yield of debt securities at March 31, 2026, by contractual maturity, are listed in the table below. Securities not due at a single maturity date are shown separately.

Weighted

Amortized

Average

Fair

Securities available-for-sale

  ​ ​ ​

Cost

  ​ ​ ​

Yield

  ​ ​ ​

Value

  ​

Due in one year or less

$

102,882

4.00

%

$

103,058

Due after one year through five years

122,963

3.91

122,569

Due after five years through ten years

142,578

3.52

138,495

Due after ten years

75,974

3.14

72,833

444,397

3.67

436,955

Mortgage-backed and collateralized mortgage obligations

486,429

2.81

448,541

Asset-backed securities

45,318

3.64

44,505

Collateralized loan obligations

184,941

5.21

184,711

Equity securities

714

-

731

Total securities available-for-sale

$

1,161,799

3.55

%

$

1,115,443

At March 31, 2026, the Company had no securities issued from any one originator, other than the U.S. Government and its agencies, which individually amounted to over 10% of the Company’s stockholders’ equity.

Securities with unrealized losses with no corresponding allowance for credit losses at March 31, 2026, and December 31, 2025, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position, were as follows (in thousands except for number of securities):

Less than 12 months

12 months or more

March 31, 2026

in an unrealized loss position

in an unrealized loss position

Total

Number of

Unrealized

Fair

Number of

Unrealized

Fair

Number of

Unrealized

Fair

Securities available-for-sale

  ​ ​ ​

Securities

  ​ ​

Losses

  ​ ​

Value

  ​ ​

Securities

  ​ ​

Losses

  ​ ​

Value

  ​ ​

Securities

  ​ ​

Losses

  ​ ​

Value

U.S. government agencies

1

$

171

$

39,516

7

$

153

$

29,109

8

$

324

$

68,625

U.S. government agencies mortgage-backed

-

-

-

126

7,129

74,618

126

7,129

74,618

States and political subdivisions

19

180

52,366

19

7,961

74,514

38

8,141

126,880

Collateralized mortgage obligations

9

85

31,813

127

31,400

276,485

136

31,485

308,298

Asset-backed securities

5

168

11,090

9

1,114

22,924

14

1,282

34,014

Collateralized loan obligations

15

219

113,078

2

35

9,976

17

254

123,054

Total securities available-for-sale

49

$

823

$

247,863

290

$

47,792

$

487,626

339

$

48,615

$

735,489

Less than 12 months

12 months or more

December 31, 2025

in an unrealized loss position

in an unrealized loss position

Total

Number of

Unrealized

Fair

Number of

Unrealized

Fair

Number of

Unrealized

Fair

Securities available-for-sale

  ​ ​ ​

Securities

  ​ ​

Losses

  ​ ​

Value

  ​ ​

Securities

  ​ ​

Losses

  ​ ​

Value

  ​ ​

Securities

  ​ ​

Losses

  ​ ​

Value

U.S. government agencies

-

$

-

$

-

7

$

245

$

29,176

7

$

245

$

29,176

U.S. government agencies mortgage-backed

1

36

10,572

126

7,083

78,208

127

7,119

88,780

States and political subdivisions

1

4

5,046

29

7,437

104,483

30

7,441

109,529

Collateralized mortgage obligations

5

19

6,287

130

30,552

288,228

135

30,571

294,515

Asset-backed securities

7

139

14,927

7

1,068

20,164

14

1,207

35,091

Collateralized loan obligations

12

239

87,299

-

-

-

12

239

87,299

Total securities available-for-sale

26

$

437

$

124,131

299

$

46,385

$

520,259

325

$

46,822

$

644,390

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Each quarter, we perform an analysis to determine if any of the unrealized losses on securities available-for-sale are comprised of credit losses as compared to unrealized losses due to market interest rate adjustments. Our assessment includes a review of the unrealized loss for each security issuance held; the financial condition and near-term prospects of the issuer, including external credit ratings and recent downgrades; and our ability and intent to hold the security for a period of time sufficient for a recovery in value. We also consider the extent to which the securities are issued by the federal government or its agencies, and any guarantee of issued amounts by those agencies. The portfolio continues to consist of a mix of fixed and floating-rate, high quality securities, largely rated AA (or better), displaying an overall effective duration of approximately 3.0 years.

There were no securities sold for the three months ended March 31, 2026 or 2025, respectively.

As of March 31, 2026, securities valued at $652.7 million were pledged for borrowings and for other purposes, a decrease from $679.5 million of securities pledged at year end 2025.

Note 4 – Loans and Allowance for Credit Losses on Loans

Major classifications of loans were as follows:

  ​ ​ ​

March 31, 2026

  ​ ​ ​

December 31, 2025

Commercial

$

845,278

$

842,130

Leases

539,116

548,256

Commercial real estate – investor

1,169,318

1,212,384

Commercial real estate – owner occupied

702,986

706,567

Construction

143,563

173,630

Residential real estate – investor

69,763

70,225

Residential real estate – owner occupied

239,711

230,432

Multifamily

357,131

339,131

HELOC

235,637

235,293

Powersport

674,116

696,959

Other 1

208,618

197,124

Total loans

5,185,237

5,252,131

Allowance for credit losses on loans

(72,126)

(72,301)

Net loans 2

$

5,113,111

$

5,179,830

1 The “Other” classification includes consumer loans, such as collector cars, manufactured homes, and solar loans, as well as overdrafts in this table and in subsequent tables within Note 4 – Loans and Allowance for Credit Losses on Loans.

2 Excludes accrued interest receivable of $23.2 million and $23.5 million at March 31, 2026, and December 31, 2025, respectively, that is recorded in other assets on the Consolidated Balance Sheets.

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Table of Contents

It is the policy of the Company to review each prospective credit prior to making a loan in order to determine if an adequate level of security or collateral has been obtained. The type of collateral, when required, will vary from liquid assets to real estate. The Company seeks to ensure access to collateral, in the event of borrower default, through adherence to lending laws, the Company’s lending standards and credit monitoring procedures. Although the Bank makes loans primarily within its market area, there are no significant concentrations of loans where the customers’ ability to honor loan terms is dependent upon a single economic sector. The real estate related categories listed above represent 56.3% and 56.5% of the portfolio at March 31, 2026, and December 31, 2025, respectively, and include a mix of owner occupied and non-owner occupied commercial real estate, residential, construction and multifamily loans.

The following tables represent the activity in the allowance for credit losses for loans, or the ACL, for the three months ended March 31, 2026 and 2025:

Provision for

Beginning

(Release of)

Ending

Allowance for credit losses

  ​ ​

Balance

  ​ ​

Credit Losses 1

  ​ ​

Charge-offs

  ​ ​

Recoveries

  ​ ​

Balance

Three months ended March 31, 2026

Commercial

$

11,183

$

2,754

$

1,328

$

30

$

12,639

Leases

2,370

154

312

115

2,327

Commercial real estate – investor

21,672

3,120

3,933

14

20,873

Commercial real estate – owner occupied

4,583

344

-

5

4,932

Construction

1,527

(325)

-

-

1,202

Residential real estate – investor

759

(7)

-

2

754

Residential real estate – owner occupied

1,879

67

-

7

1,953

Multifamily

1,493

115

-

-

1,608

HELOC

3,628

(17)

2

8

3,617

Powersport

17,449

3,362

4,661

767

16,917

Other

5,758

34

557

69

5,304

Total

$

72,301

$

9,601

$

10,793

$

1,017

$

72,126

1 Amount does not include the provision for unfunded commitment liability.

Provision for

Beginning

(Release of)

Ending

Allowance for credit losses

  ​ ​

Balance

  ​ ​

Credit Losses 1

  ​ ​

Charge-offs

  ​ ​

Recoveries

  ​ ​

Balance

Three months ended March 31, 2025

Commercial

$

7,813

$

3,448

$

3,446

$

32

$

7,847

Leases

2,136

148

107

14

2,191

Commercial real estate – investor

14,528

1,094

-

14

15,636

Commercial real estate – owner occupied

10,036

(2,730)

47

8

7,267

Construction

3,581

(91)

821

-

2,669

Residential real estate – investor

553

7

-

2

562

Residential real estate – owner occupied

1,509

301

-

30

1,840

Multifamily

1,876

(23)

-

-

1,853

HELOC

1,578

88

-

12

1,678

Powersport

-

-

-

-

-

Other

9

43

108

64

8

Total

$

43,619

$

2,285

$

4,529

$

176

$

41,551

1 Amount does not include the provision for unfunded commitment liability.

At March 31, 2026, our allowance for credit losses (“ACL”) on loans totaled $72.1 million, and our ACL on unfunded commitments, included in other liabilities, totaled $2.0 million. During the first three months of 2026, we recorded net provision for credit losses on loans and unfunded commitments of $9.5 million. The provision was mostly driven by increased commercial and commercial real estate charge offs, and a downgrade of one commercial relationship. Charge offs for the period ending March 31, 2026 were largely comprised of a $3.9 million charge off in commercial real estate-investor on a downtown Chicago office building that now cashflows after the restructuring; a commercial charge off of $1.3 million in the warehouse and distribution business; and higher than normal powersport net charge offs totaling $3.9 million due to continued softness in the consumer lending as seen in the broader economy. The ACL on loans excludes an allowance for unfunded commitments of $2.0 million as of March 31, 2026, $2.1 million as of December 31, 2025, and $2.0 million as of March 31, 2025, which is recorded within other liabilities on the Consolidated Balance Sheets.

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Generally, the Bank considers a loan to be collateral dependent when, based on current information and events, it is probable that foreclosure could be initiated. Additionally, the Bank will review all loans meeting the criteria for individual analysis, to determine if repayment or satisfaction of the loan is expected through the sale of collateral. This will generally be the case for credits with high loan-to-value ratios. Exceptions to this policy would include loans with guarantors or sponsors that have the means and willingness to support the obligation. Non-accruing loans with an outstanding balance of $500,000 or more are assessed on an individual loan level basis. When a financial asset is deemed collateral-dependent, the level of credit loss is measured by the difference between amortized cost of the financial asset and the fair value of collateral adjusted for estimated cost to sell. The Company had $64.7 million and $40.9 million of collateral dependent loans secured by real estate or business assets as of March 31, 2026, and December 31, 2025, respectively.

The following tables present the collateral dependent loans and the related ACL allocated by classification of loans as of March 31, 2026, and December 31, 2025:

Accounts

ACL

March 31, 2026

Real Estate

Receivable

Equipment

Equity Interests

Total

Allocation

Commercial

$

-

$

12,507

$

3,402

$

16,500

$

32,409

$

5,348

Leases

-

-

-

-

-

-

Commercial real estate – investor

11,210

-

-

-

11,210

5,547

Commercial real estate – owner occupied

17,939

-

-

-

17,939

315

Construction

1,469

-

-

-

1,469

-

Residential real estate – investor

152

-

-

-

152

-

Residential real estate – owner occupied

721

-

-

-

721

-

Multifamily

783

-

-

-

783

-

HELOC

-

-

-

-

-

-

Powersport

-

-

-

-

-

Other

-

-

-

-

-

-

Total

$

32,274

$

12,507

$

3,402

$

16,500

$

64,683

$

11,210

Accounts

ACL

December 31, 2025

Real Estate

Receivable

Equipment

Equity Interests

Total

Allocation

Commercial

$

-

$

5,960

$

2,055

$

-

$

8,015

$

762

Leases

-

-

-

-

-

-

Commercial real estate – investor

11,345

-

-

-

11,345

5,682

Commercial real estate – owner occupied

19,809

-

-

-

19,809

-

Construction

-

-

-

-

-

-

Residential real estate – investor

26

-

-

-

26

-

Residential real estate – owner occupied

844

-

-

-

844

-

Multifamily

782

-

-

-

782

-

HELOC

53

-

-

-

53

-

Powersport

-

-

-

-

-

Other

-

-

-

-

-

-

Total

$

32,859

$

5,960

$

2,055

$

-

$

40,874

$

6,444

An aged analysis of past due loans by classification of loans was as follows:

90 days or

90 Days or

Greater Past

30-59 Days

60-89 Days

Greater Past

Total Past

Due and

March 31, 2026

Past Due

  ​ ​ ​

Past Due

  ​ ​ ​

Due

  ​ ​ ​

Due

  ​ ​ ​

Current

  ​ ​ ​

Total Loans

  ​ ​ ​

Accruing

Commercial

$

6,512

-

4,053

10,565

834,713

$

845,278

$

581

Leases

1,976

391

1,910

4,277

534,839

539,116

348

Commercial real estate – investor

29,415

1,750

5,182

36,347

1,132,971

1,169,318

5,182

Commercial real estate – owner occupied

1,222

784

20,122

22,128

680,858

702,986

3,578

Construction

-

-

2,086

2,086

141,477

143,563

-

Residential real estate – investor

198

356

152

706

69,057

69,763

-

Residential real estate – owner occupied

2,359

194

617

3,170

236,541

239,711

90

Multifamily

311

-

1,072

1,383

355,748

357,131

-

HELOC

1,610

851

589

3,050

232,587

235,637

60

Powersport

11,497

3,484

2,363

17,344

656,772

674,116

2,190

Other

659

135

1,112

1,906

206,712

208,618

839

Total

$

55,759

$

7,945

$

39,258

$

102,962

$

5,082,275

$

5,185,237

$

12,868

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Table of Contents

90 days or

90 Days or

Greater Past

30-59 Days

60-89 Days

Greater Past

Total Past

Due and

December 31, 2025

Past Due

  ​ ​ ​

Past Due

  ​ ​ ​

Due

  ​ ​ ​

Due

  ​ ​ ​

Current

  ​ ​ ​

Total Loans

  ​ ​ ​

Accruing

Commercial

$

565

-

4,746

5,311

836,819

$

842,130

$

1,241

Leases

2,116

595

1,677

4,388

543,868

548,256

471

Commercial real estate – investor

10,604

89

-

10,693

1,201,691

1,212,384

-

Commercial real estate – owner occupied

7,176

819

11,389

19,384

687,183

706,567

250

Construction

1,546

1,349

635

3,530

170,100

173,630

-

Residential real estate – investor

120

699

152

971

69,254

70,225

-

Residential real estate – owner occupied

7,983

562

757

9,302

221,130

230,432

141

Multifamily

404

313

1,070

1,787

337,344

339,131

-

HELOC

5,219

441

451

6,111

229,182

235,293

-

Powersport

13,796

4,860

2,778

21,434

675,525

696,959

2,710

Other

1,873

702

217

2,792

194,332

197,124

66

Total

$

51,402

$

10,429

$

23,872

$

85,703

$

5,166,428

$

5,252,131

$

4,879

The table presents all nonaccrual loans as of March 31, 2026, and December 31, 2025:

Nonaccrual loan detail

  ​ ​ ​

March 31, 2026

  ​ ​ ​

With no ACL

December 31, 2025

  ​ ​ ​

With no ACL

Commercial

$

21,946

$

14,446

$

8,520

$

5,520

Leases

2,604

2,604

2,428

2,428

Commercial real estate – investor

11,241

31

11,377

32

Commercial real estate – owner occupied

18,690

4,799

19,493

19,493

Construction

2,086

2,086

737

737

Residential real estate – investor

669

669

681

681

Residential real estate – owner occupied

1,826

1,826

1,711

1,711

Multifamily

1,489

1,489

1,494

1,494

HELOC

1,543

1,543

1,222

1,222

Powersport

204

204

68

68

Other

338

338

221

221

Total

$

62,636

$

30,035

$

47,952

$

33,607

The Company recognized $4,000 of interest on nonaccrual loans during the three months ended March 31, 2026, and $39,000 of interest on nonaccrual loans during the three months ended March 31, 2025, respectively.

19

Table of Contents

Credit Quality Indicators

The Company categorizes loans into credit risk categories based on current financial information, overall debt service coverage, comparison to industry averages, historical payment experience, and current economic trends. This analysis includes loans with outstanding balances or commitments greater than $50,000 and excludes homogeneous loans such as home equity lines of credit residential mortgages, powersports, and other loan categories. Loans with a classified risk rating are reviewed quarterly regardless of size or loan type. The Company uses the following definitions for classified risk ratings:

Special Mention. Loans classified as special mention have a potential weakness that deserves management’s close attention. If left uncorrected, these potential weaknesses may result in deterioration of the repayment prospects for the loan at some future date.

Substandard. Loans classified as substandard are inadequately protected by the current net worth and paying capacity of the obligor or of the collateral pledged, if any. Loans so classified have a well-defined weakness or weaknesses that jeopardize the liquidation of the debt. They are characterized by the distinct possibility that the Bank will sustain some loss if the deficiencies are not corrected. The substandard credit quality indicator includes both potential problem loans that are currently performing and nonperforming loans.

Doubtful. Loans classified as doubtful have all the weaknesses inherent in those classified as substandard, with the added characteristic that the weaknesses make collection or liquidation in full, on the basis of currently existing facts, conditions, and values, highly questionable and improbable.

Credits that are not covered by the definitions above are pass credits, which are not considered to be adversely rated.

For residential owner-occupied, HELOC, powersport, and the other loan portfolios, the Company evaluates credit quality based on the

aging status of the loan and by payment activity. Nonperforming loans are those that are either 90 days or more past due and accruing or

are on nonaccrual, and all other loans not meeting this criteria are considered performing.

Credit quality indicators by loan classification and contractual loan origination date at March 31, 2026, were as follows:

  ​

2026

  ​

2025

  ​

2024

  ​

2023

  ​

2022

  ​

Prior

  ​

Revolving
Loans

  ​

Revolving
Loans
Converted
To Term
Loans

  ​

Total

Commercial

Pass

$

54,297

$

250,771

$

144,913

$

90,559

$

20,994

$

16,475

$

202,190

$

-

$

780,199

Special Mention

-

-

3,240

-

173

-

11,026

-

14,439

Substandard

-

206

12,869

2,166

3,402

189

27,308

-

46,140

Doubtful

-

-

4,500

-

-

-

-

-

4,500

Total commercial

54,297

250,977

165,522

92,725

24,569

16,664

240,524

-

845,278

Leases

Pass

46,629

231,261

$

155,167

71,663

22,207

8,915

-

-

535,842

Special Mention

-

-

-

347

233

90

-

-

670

Substandard

-

-

420

850

1,334

-

-

-

2,604

Total leases

46,629

231,261

155,587

72,860

23,774

9,005

-

-

539,116

Commercial real estate – investor

Pass

27,246

278,723

185,373

117,511

252,926

267,194

6,636

-

1,135,609

Special Mention

-

448

7,176

-

1,148

9,978

-

-

18,750

Substandard

-

-

9,553

1,676

1,677

1,964

89

-

14,959

Total commercial real estate – investor

27,246

279,171

202,102

119,187

255,751

279,136

6,725

-

1,169,318

Commercial real estate – owner occupied

Pass

27,254

201,845

80,958

59,790

78,693

177,985

9,490

-

636,015

Special Mention

-

-

-

1,418

3,203

1,756

-

-

6,377

Substandard

-

2,109

5,511

21,130

6,833

24,262

-

749

60,594

Total commercial real estate – owner occupied

27,254

203,954

86,469

82,338

88,729

204,003

9,490

749

702,986

20

Table of Contents

Credit quality indicators by loan classification and contractual loan origination date at March 31, 2026, continued:

  ​

2026

  ​

2025

  ​

2024

  ​

2023

  ​

2022

  ​

Prior

  ​

Revolving
Loans

  ​

Revolving
Loans
Converted
To Term
Loans

  ​

Total

Construction

Pass

1,005

65,952

35,787

1,859

24,846

1,131

-

-

130,580

Special Mention

-

-

-

-

-

-

-

-

-

Substandard

-

102

1,936

875

9,731

339

-

-

12,983

Total construction

1,005

66,054

37,723

2,734

34,577

1,470

-

-

143,563

Residential real estate – investor

Pass

2,114

11,900

5,407

3,022

15,005

26,702

4,601

-

68,751

Special Mention

-

-

-

-

-

-

-

-

-

Substandard

-

-

-

-

-

1,012

-

-

1,012

Total residential real estate – investor

2,114

11,900

5,407

3,022

15,005

27,714

4,601

-

69,763

Residential real estate – owner occupied

Pass

11,329

43,354

10,676

24,848

35,061

111,349

1,208

-

237,825

Special Mention

-

-

-

-

-

-

-

-

-

Substandard

-

-

-

147

337

1,402

-

-

1,886

Total residential real estate – owner occupied

11,329

43,354

10,676

24,995

35,398

112,751

1,208

-

239,711

Multifamily

Pass

5,747

57,219

19,792

79,042

96,040

96,527

1,275

-

355,642

Special Mention

-

-

-

-

-

-

-

-

-

Substandard

-

-

-

124

889

476

-

-

1,489

Total multifamily

5,747

57,219

19,792

79,166

96,929

97,003

1,275

-

357,131

HELOC

Pass

1,068

2,810

2,117

1,658

1,541

4,605

220,006

-

233,805

Special Mention

-

-

-

-

-

-

-

-

-

Substandard

-

-

-

-

-

248

1,584

-

1,832

Total HELOC

1,068

2,810

2,117

1,658

1,541

4,853

221,590

-

235,637

Powersport

Pass

73,258

288,187

154,278

96,362

46,199

15,628

-

-

673,912

Special Mention

-

-

-

-

-

-

-

-

-

Substandard

-

20

105

45

9

25

-

-

204

Total Powersport

73,258

288,207

154,383

96,407

46,208

15,653

-

-

674,116

Other

Pass

27,171

75,836

26,477

17,500

46,381

7,872

7,012

-

208,249

Special Mention

-

-

-

-

-

-

-

-

-

Substandard

-

-

-

141

198

30

-

-

369

Total other

27,171

75,836

26,477

17,641

46,579

7,902

7,012

-

208,618

Total loans

Pass

277,118

1,507,858

820,945

563,814

639,893

734,383

452,418

-

4,996,429

Special Mention

-

448

10,416

1,765

4,757

11,824

11,026

-

40,236

Substandard

-

2,437

30,394

27,154

24,410

29,947

28,981

749

144,072

Doubtful

-

-

4,500

-

-

-

-

-

4,500

Total loans

$

277,118

$

1,510,743

$

866,255

$

592,733

$

669,060

$

776,154

$

492,425

$

749

$

5,185,237

21

Table of Contents

Credit quality indicators by loan classification and loan origination date at December 31, 2025, were as follows:

  ​

2025

  ​

2024

  ​

2023

  ​

2022

  ​

2021

  ​

Prior

  ​

Revolving
Loans

  ​

Revolving
Loans
Converted
To Term
Loans

  ​

Total

Commercial

Pass

$

275,155

$

161,529

$

94,487

$

22,843

$

8,699

$

9,730

$

214,846

$

125

$

787,414

Special Mention

-

-

-

212

-

-

2,917

-

3,129

Substandard

231

926

19,241

3,611

291

-

27,287

-

51,587

Total commercial

275,386

162,455

113,728

26,666

8,990

9,730

245,050

125

842,130

Leases

Pass

247,515

172,825

$

84,533

27,993

10,164

2,038

-

-

545,068

Special Mention

-

-

374

263

123

-

-

-

760

Substandard

-

214

469

1,745

-

-

-

-

2,428

Total leases

247,515

173,039

85,376

30,001

10,287

2,038

-

-

548,256

Commercial real estate – investor

Pass

296,219

217,761

120,630

255,701

199,993

99,144

6,371

-

1,195,819

Special Mention

82

-

-

-

41

2,197

-

-

2,320

Substandard

-

9,703

1,677

1,690

-

1,175

-

-

14,245

Total commercial real estate – investor

296,301

227,464

122,307

257,391

200,034

102,516

6,371

-

1,212,384

Commercial real estate – owner occupied

Pass

193,988

76,480

67,749

76,670

106,107

103,545

10,309

-

634,848

Special Mention

-

-

161

3,542

2,153

1,782

-

-

7,638

Substandard

58

-

20,929

8,996

20,252

13,846

-

-

64,081

Total commercial real estate – owner occupied

194,046

76,480

88,839

89,208

128,512

119,173

10,309

-

706,567

Construction

Pass

53,522

48,906

31,121

27,500

332

828

-

-

162,209

Special Mention

-

-

-

-

-

-

-

-

-

Substandard

102

-

1,454

9,526

-

339

-

-

11,421

Total construction

53,624

48,906

32,575

37,026

332

1,167

-

-

173,630

Residential real estate – investor

Pass

13,993

5,729

3,677

15,256

15,288

10,743

4,397

-

69,083

Special Mention

-

-

-

-

-

-

-

-

-

Substandard

-

-

-

-

461

681

-

-

1,142

Total residential real estate – investor

13,993

5,729

3,677

15,256

15,749

11,424

4,397

-

70,225

Residential real estate – owner occupied

Pass

42,941

11,580

25,594

35,826

30,264

81,123

1,207

-

228,535

Special Mention

-

-

-

-

-

-

-

-

-

Substandard

-

-

151

202

142

1,402

-

-

1,897

Total residential real estate – owner occupied

42,941

11,580

25,745

36,028

30,406

82,525

1,207

-

230,432

Multifamily

Pass

56,753

20,133

50,464

96,747

70,496

40,926

2,118

-

337,637

Special Mention

-

-

-

-

-

-

-

-

-

Substandard

-

-

124

892

313

165

-

-

1,494

Total multifamily

56,753

20,133

50,588

97,639

70,809

41,091

2,118

-

339,131

HELOC

Pass

2,888

2,192

1,700

1,646

278

4,480

220,643

-

233,827

Special Mention

-

-

-

-

-

-

-

-

-

Substandard

-

-

-

-

-

240

1,226

-

1,466

Total HELOC

2,888

2,192

1,700

1,646

278

4,720

221,869

-

235,293

Powersport

Pass

323,072

180,099

114,212

57,740

17,237

4,531

-

-

696,891

Special Mention

-

-

-

-

-

-

-

-

-

Substandard

-

22

44

-

-

2

-

-

68

Total Powersport

323,072

180,121

114,256

57,740

17,237

4,533

-

-

696,959

Other

Pass

81,405

31,889

19,599

48,615

1,729

7,282

6,335

-

196,854

Special Mention

-

-

-

-

-

-

-

-

-

Substandard

-

-

163

74

27

6

-

-

270

Total other

81,405

31,889

19,762

48,689

1,756

7,288

6,335

-

197,124

Total loans

Pass

1,587,451

929,123

613,766

666,537

460,587

364,370

466,226

125

5,088,185

Special Mention

82

-

535

4,017

2,317

3,979

2,917

-

13,847

Substandard

391

10,865

44,252

26,736

21,486

17,856

28,513

-

150,099

Total loans

$

1,587,924

$

939,988

$

658,553

$

697,290

$

484,390

$

386,205

$

497,656

$

125

$

5,252,131

22

Table of Contents

The following vintage tables present the amortized cost basis of non-risk rated loans by class and year of origination, based on the Company’s credit quality indicator for such loans as of March 31, 2026 and December 31, 2025. For these loan classes, the Company monitors credit quality based on performing and nonperforming status rather than internal risk ratings.

March 31, 2026

  ​

2026

  ​

2025

  ​

2024

  ​

2023

  ​

2022

  ​

Prior

  ​

Revolving
Loans

  ​

Revolving
Loans
Converted
To Term
Loans

  ​

Total

Residential real estate – owner occupied

Performing

$

11,329

43,354

10,676

24,848

35,061

111,319

1,208

$

-

$

237,795

Nonperforming

-

-

-

147

337

1,432

-

-

1,916

Total Residential real estate – owner occupied

11,329

43,354

10,676

24,995

35,398

112,751

1,208

-

239,711

HELOC

Performing

1,068

2,810

2,057

1,658

1,541

4,767

220,133

-

234,034

Nonperforming

-

-

60

-

-

86

1,457

-

1,603

Total HELOC

1,068

2,810

2,117

1,658

1,541

4,853

221,590

-

235,637

Powersport

Performing

73,258

287,490

153,788

95,830

45,936

15,420

-

-

671,722

Nonperforming

-

717

595

577

272

233

-

-

2,394

Total Powersport

73,258

288,207

154,383

96,407

46,208

15,653

-

-

674,116

Other

Performing

27,171

75,836

26,465

17,499

46,346

7,872

6,252

-

207,441

Nonperforming

-

-

12

142

233

30

760

-

1,177

Total Other

27,171

75,836

26,477

17,641

46,579

7,902

7,012

-

208,618

Total non-risk rated loans

Performing

112,826

409,490

192,986

139,835

128,884

139,378

227,593

-

1,350,992

Nonperforming

-

717

667

866

842

1,781

2,217

-

7,090

Total non-risk rated loans

$

112,826

410,207

193,653

140,701

129,726

141,159

229,810

-

1,358,082

December 31, 2025

  ​

2025

  ​

2024

  ​

2023

  ​

2022

  ​

2021

  ​

Prior

  ​

Revolving
Loans

  ​

Revolving
Loans
Converted
To Term
Loans

  ​

Total

Residential real estate – owner occupied

Performing

$

42,941

$

11,580

$

25,594

$

35,826

$

30,264

$

81,168

$

1,207

$

-

$

228,580

Nonperforming

-

-

151

202

142

1,357

-

-

1,852

Total Residential real estate – owner occupied

42,941

11,580

25,745

36,028

30,406

82,525

1,207

-

230,432

HELOC

Performing

2,888

2,192

1,700

1,646

278

4,499

220,868

-

234,071

Nonperforming

-

-

-

221

1,001

-

1,222

Total HELOC

2,888

2,192

1,700

1,646

278

4,720

221,869

-

235,293

Powersport

Performing

322,369

179,391

113,725

57,266

17,026

4,404

-

-

694,181

Nonperforming

703

730

531

474

211

129

-

-

2,778

Total Powersport

323,072

180,121

114,256

57,740

17,237

4,533

-

-

696,959

Other

Performing

81,405

31,889

19,596

48,615

1,730

7,267

6,335

-

196,837

Nonperforming

-

-

166

74

26

21

-

287

Total Other

81,405

31,889

19,762

48,689

1,756

7,288

6,335

-

197,124

Total non-risk rated loans

Performing

449,603

225,052

160,615

143,353

49,298

97,338

228,410

-

1,353,669

Nonperforming

703

730

848

750

379

1,728

1,001

-

6,139

Total non-risk rated loans

$

450,306

225,782

161,463

144,103

49,677

99,066

229,411

-

1,359,808

23

Table of Contents

The gross charge-offs activity by loan type and year of origination for the three months ended March 31, 2026 and 2025, were as follows:

Three months ended March 31, 2026

  ​

2026

  ​

2025

  ​

2024

  ​

2023

  ​

2022

  ​

Prior

  ​

Total

Commercial

$

-

-

34

1,290

-

4

$

1,328

Leases

-

-

-

-

310

2

312

Commercial real estate – investor

-

-

-

-

-

3,933

3,933

Commercial real estate – owner occupied

-

-

-

-

-

-

-

Construction

-

-

-

-

-

-

-

Residential real estate – investor

-

-

-

-

-

-

-

Residential real estate – owner occupied

-

-

-

-

-

-

-

Multifamily

-

-

-

-

-

-

-

HELOC

-

-

-

2

-

-

2

Powersport

5

1,646

1,230

880

616

284

4,661

Other

-

-

-

50

426

81

557

Total

$

5

$

1,646

$

1,264

$

2,222

$

1,352

$

4,304

$

10,793

Three months ended March 31, 2025

  ​

2025

  ​

2024

  ​

2023

  ​

2022

  ​

2021

  ​

Prior

  ​

Total

Commercial

$

-

-

2,050

-

1,391

5

$

3,446

Leases

-

-

85

22

-

-

107

Commercial real estate – investor

-

-

-

-

-

-

-

Commercial real estate – owner occupied

-

-

-

-

-

47

47

Construction

-

-

-

821

-

-

821

Residential real estate – investor

-

-

-

-

-

-

-

Residential real estate – owner occupied

-

-

-

-

-

-

-

Multifamily

-

-

-

-

-

-

-

HELOC

-

-

-

-

-

-

-

Powersport

-

-

-

-

-

-

-

Other

-

-

5

-

-

103

108

Total

$

-

$

-

$

2,140

$

843

$

1,391

$

155

$

4,529

The Company had $1.6 million and $379,000 in residential real estate loans in the process of foreclosure as of March 31, 2026, and December 31, 2025, respectively.

24

Table of Contents

There were 15 loans modified during the three-month period ending March 31, 2026, totaling $26.8 million in aggregate, which were experiencing financial difficulty. Of the 15 loans modified in the first three months of 2026, three loans had also been modified in prior periods. There were 13 loans modified during the three-month period ending March 31, 2025, totaling $46.7 million in aggregate, which were experiencing financial difficulty.

The following tables present the amortized costs basis of loans at March 31, 2026, and March 31, 2025, that were both experiencing financial difficulty and modified during the three months ended March 31, 2026, and March 31, 2025, by class and by type of modification. The percentage of the amortized cost basis of loans that were modified to borrowers in financial distress as compared to the amortized cost basis of each class of financing receivable is also presented below.

Three months ended March 31, 2026

Term Modification

Combination - Term, Interest Rate and Payment Modification

Combination - Term and Interest Rate Modification

Combination - Term and Payment Modification 1

Total Loans Modified

% of Total Loan Classification Modified to Total Loan Classification

Commercial

$

4,055

$

-

$

3,500

$

-

$

7,555

0.9

%

Commercial real estate – investor

-

-

-

89

89

0.0

Commercial real estate – owner occupied

18,873

-

-

-

18,873

2.7

Construction

-

-

-

-

-

-

HELOC

153

-

-

-

153

0.1

Powersport

-

80

-

-

80

0.0

Total

$

23,081

$

80

$

3,500

$

89

$

26,750

0.5

%

1 Payment modifications are either contractual delays in payment or a modification of the payment amount.

Three months ended March 31, 2025

Term Modification

Combination - Term, Interest Rate and Payment Modification

Combination - Term and Interest Rate Modification

Combination - Term and Payment Modification 1

Total Loans Modified

% of Total Loan Classification Modified to Total Loan Classification

Commercial

$

312

$

-

$

-

$

6,547

$

6,859

0.9

%

Commercial real estate – investor

-

-

12,331

-

12,331

1.1

Commercial real estate – owner occupied

13,102

-

-

1,167

14,269

2.1

Construction

13,212

-

-

-

13,212

6.4

HELOC

-

-

-

-

-

-

Powersport

-

-

-

-

-

-

Total

$

26,626

$

-

$

12,331

$

7,714

$

46,671

1.2

%

1 Payment modifications are either contractual delays in payment or a modification of the payment amount.

The Company closely monitors the performance of loan modifications to borrowers experiencing financial difficulty. The following tables present the performance of loans that have been modified in the last twelve months as of March 31, 2026, and March 31, 2025.

March 31, 2026

30-59 days past due

60-89 Days Past Due

90 Days or Greater Past Due

Total Past Due

Current

Total Modifications

Commercial

$

3,500

$

-

$

3,000

$

6,500

$

10,525

$

17,025

Commercial real estate – investor

11,210

-

89

11,299

31

11,330

Commercial real estate – owner occupied

-

56

15,217

15,273

22,369

37,642

Construction

-

-

-

-

-

-

Multifamily

-

-

-

-

-

-

HELOC

-

-

-

-

238

238

Powersport

16

-

20

36

110

146

Other

-

-

-

-

23

23

Total

$

14,726

$

56

$

18,326

$

33,108

$

33,296

$

66,404

March 31, 2025

30-59 days past due

60-89 Days Past Due

90 Days or Greater Past Due

Total Past Due

Current

Total Modifications

Commercial

$

-

$

-

$

-

$

-

$

9,950

$

9,950

Commercial real estate – investor

-

-

-

-

12,331

12,331

Commercial real estate – owner occupied

-

-

-

-

17,592

17,592

Construction

-

-

-

-

13,212

13,212

Multifamily

-

-

-

-

1,191

1,191

HELOC

-

-

-

-

-

-

Powersport

-

-

-

-

-

-

Other

-

-

-

-

-

-

Total

$

-

$

-

$

-

$

-

$

54,276

$

54,276

25

Table of Contents

The following tables summarize the financial effect of the loan modifications presented above to borrowers experiencing financial difficulty for the three months ended March 31, 2026 and March 31, 2025. The financial impact of these modifications was immaterial.

Three months ended March 31, 2026

Weighted-Average Term Extension (In Months)

Weighted-Average Interest Rate Change

Weighted-Average Delay of Payment (In Months)

Commercial

4.08

1.00

%

-

Commercial real estate – investor

12.00

-

-

Commercial real estate – owner occupied

6.00

-

-

Construction

-

-

-

HELOC

24.00

-

-

Powersport

(0.95)

(1.64)

-

Total

5.56

0.94

%

-

Three months ended March 31, 2025

Weighted-Average Term Extension (In Months)

Weighted-Average Interest Rate Change

Weighted-Average Delay of Payment (In Months)

Commercial

3.00

-

%

2.00

Leases

-

-

-

Commercial real estate – investor

9.00

(1.00)

-

Commercial real estate – owner occupied

3.44

-

2.00

Construction

9.00

-

-

HELOC

-

-

-

Powersport

-

-

-

Total

6.42

(1.00)

%

2.00

Note 5 – Other Real Estate Owned

Details related to the activity in the other real estate owned (“OREO”) portfolio, net of valuation reserve, for the periods presented are itemized in the following table:

Three Months Ended

  ​ ​ ​

March 31, 

  ​ ​ ​

Other real estate owned

  ​ ​ ​

2026

  ​ ​ ​

2025

  ​ ​ ​

Balance at beginning of period

$

1,427

$

21,617

Property additions, net of participation sold

632

-

Less:

Carrying value of property disposals, net of participation sold

1,427

18,285

Period valuation adjustments

-

454

Balance at end of period

$

632

$

2,878

Activity in the valuation allowance was as follows:

  ​ ​ ​

Three Months Ended

  ​ ​ ​

March 31, 

  ​ ​ ​

  ​ ​ ​

2026

  ​ ​ ​

2025

  ​ ​ ​

Balance at beginning of period

$

632

$

1,862

Provision for valuation reserves

-

454

Reductions taken on sales

(632)

(1,463)

Balance at end of period

$

-

$

853

Expenses related to OREO, net of lease revenue, include:

Three Months Ended

March 31, 

  ​ ​ ​

  ​ ​ ​

2026

  ​ ​ ​

2025

  ​ ​ ​

(Gain) loss on sales, net

$

(98)

$

236

Provision for valuation reserves

-

454

Operating (income) expense (1)

(86)

1,913

Less:

Lease revenue

2

730

Net OREO expense

$

(186)

$

1,873

1 Operating income for the three months ended March 31, 2026 includes $235,000 net gain on transfer as the fair value less cost to sell on one property transfer exceeded the book value of the loan.

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Table of Contents

Note 6 – Deposits

Major classifications of deposits were as follows:

  ​ ​ ​

March 31, 2026

  ​ ​ ​

December 31, 2025

  ​

Noninterest bearing demand

$

1,755,548

$

1,739,117

Savings

1,117,316

1,121,888

NOW accounts

701,712

693,573

Money market accounts

976,010

930,079

Certificates of deposit of less than $100,000

440,553

489,879

Certificates of deposit of $100,000 through $250,000

376,868

412,655

Certificates of deposit of more than $250,000

196,992

208,878

Total deposits

$

5,564,999

$

5,596,069

Note 7 – Borrowings

The following table is a summary of borrowings as of March 31, 2026, and December 31, 2025. Junior subordinated debentures are discussed in more detail in Note 8:

  ​ ​ ​

March 31, 2026

  ​ ​ ​

December 31, 2025

  ​

Securities sold under repurchase agreements

$

23,130

$

23,769

Other short-term borrowings

200,000

215,000

Junior subordinated debentures1

25,774

25,774

Subordinated debentures

59,574

59,552

Notes payable and other borrowings2

14,837

14,825

Total borrowings

$

323,315

$

338,920

1 See Note 8: Junior Subordinated Debentures.

2 Long-term FHLBC advance, net of purchase accounting adjustment.

The Company enters into deposit sweep transactions where the transaction amounts are secured by pledged securities. These transactions consistently mature overnight from the transaction date and are governed by sweep repurchase agreements. All sweep repurchase agreements are treated as financings secured by U.S. government agencies and collateralized mortgage-backed securities, and had a carrying amount of $23.1 million at March 31, 2026, and $23.8 million at December 31, 2025. The average amount and weighted average rate for the quarter ended March 31, 2026 was $24.8 million and 0.82% with the maximum month-end amount recorded at $27.6 million at February 28, 2026. The average amount and weighted average rate for the quarter ended December 31, 2025 was $23.5 million and 0.76% with the maximum month-end amount recorded at $23.8 million at December 31, 2025. The fair value of the pledged collateral was $73.7 million at March 31, 2026, and $74.0 million at December 31, 2025. At March 31, 2026, there were no customers with secured balances exceeding 10% of stockholders’ equity.

The Company’s borrowings at the FHLBC require the Bank to be a member and invest in the stock of the FHLBC. Total borrowings are generally limited to the lower of 35% of total assets or the book value of eligible pledged assets after application of FHLBC margins and collateral valuation adjustments. The outstanding balance of our short-term FHLBC advances was $200.0 million as of March 31, 2026, and $215.0 million as of December 31, 2025. The outstanding balance of our long-term FHLBC advances, net of purchase accounting adjustments, was $14.8 million as of March 31, 2026, and $14.8 million as of December 31, 2025. FHLBC stock held at March 31, 2026, was valued at $10.6 million, and any potential FHLBC advances were collateralized by loans and securities with a principal balance of $1.50 billion, which carried a FHLBC-calculated combined collateral value of $973.7 million. The Company had excess collateral of $757.4 million available to secure borrowings at March 31, 2026.

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Table of Contents

In the second quarter of 2021, we issued $60.0 million in aggregate principal amount of our 3.50% Fixed-to-Floating Rate Subordinated Notes due April 15, 2031 (the “Notes”). The Company used the net proceeds from the offering for general corporate purposes. The Notes bear interest at a fixed annual rate of 3.50%, from and including the date of issuance to but excluding April 15, 2026, payable semi-annually in arrears. From and including April 15, 2026, to, but excluding the maturity date or early redemption date, the interest rate will reset quarterly to an interest rate per annum equal to three-month Term SOFR (as defined by the Note) plus 273 basis points, payable quarterly in arrears. As of March 31, 2026, and December 31, 2025, we had $59.6 million of subordinated debentures outstanding, net of deferred issuance cost. On April 15, 2026, the Company redeemed $30.0 million aggregate principal amount of the Notes. See Note 1 – Subsequent Events for additional information.

The Company also has an undrawn line of credit of $30.0 million with a correspondent bank to be used for short-term funding needs; advances under this line can be outstanding up to 360 days from the date of issuance.

Note 8 – Junior Subordinated Debentures

The Company issued $25.0 million of cumulative trust preferred securities through a private placement completed by an unconsolidated subsidiary, Old Second Capital Trust II, in April 2007. These trust preferred securities mature in 30 years, but subject to regulatory approval, can be called in whole or in part on a quarterly basis commencing June 15, 2017. The quarterly cash distributions on the securities were fixed at 6.77% through June 15, 2017, and now have a floating rate of 150 basis points over three-month SOFR. Upon conversion to a floating rate, a cash flow hedge was initiated which resulted in the total interest rate paid on the debt of 4.66% for the quarter ended March 31, 2026, and 4.53% for the quarter ended March 31, 2025. The Company issued a $25.8 million subordinated debenture to Old Second Capital Trust II in return for the aggregate net proceeds of this trust preferred offering. The interest rate and payment frequency on the debenture are equivalent to the cash distribution basis on the trust preferred securities.

The junior subordinated debentures issued by the Company are disclosed on the Consolidated Balance Sheets, and the related interest expense for each issuance is included in the Consolidated Statements of Income. As of March 31, 2026, and December 31, 2025, the remaining unamortized debt issuance costs related to the junior subordinated debentures were less than $1,000 and are included as a reduction to the balance of the junior subordinated debentures on the Consolidated Balance Sheets. The remaining deferred issuance costs on the junior subordinated debentures related to the issuance of Old Second Capital Trust II will be amortized to interest expense over the remainder of the 30-year term of the notes and are included in the Consolidated Statements of Income.

Note 9 – Equity Compensation Plans

Stock-based awards are outstanding under the Company’s 2019 Equity Incentive Plan, as amended and restated (the “2019 Plan”). The 2019 Plan was originally approved at the May 2019 annual stockholders’ meeting and authorized 600,000 shares, and at the May 2021 annual stockholders’ meeting, the Company obtained stockholder approval to increase the number of shares of common stock authorized for issuance under the 2019 Plan by 1,200,000 shares, from 600,000 shares to 1,800,000 shares. At the May 2025 annual stockholders’ meeting, the Company obtained stockholder approval to increase the number of shares of common stock authorized for issuance under the 2019 Plan by an additional 800,000 shares, from 1,800,000 shares to 2,600,000 shares. Following the approval of the 2019 Plan, no further awards will be granted under any other prior plan.

The 2019 Plan authorizes the granting of qualified stock options, non-qualified stock options, restricted stock, restricted stock units, and stock appreciation rights (“SARs”); to date only restricted stock units have been awarded. Awards may be granted to selected directors, officers, employees or eligible service providers under the 2019 Plan at the discretion of the Compensation Committee of the Company’s Board of Directors. As of March 31, 2026, 1,084,444 shares remained available for issuance under the 2019 Plan.

Generally, restricted stock units granted under the 2019 Plan vest three years from the grant date, but the Compensation Committee of the Company’s Board of Directors has discretionary authority to change the terms of particular awards including the vesting schedule.

28

Table of Contents

Under the 2019 Plan, unless otherwise provided in an award agreement, upon the occurrence of a change in control, all equity awards then held by the participant will become fully exercisable immediately if, and all stock awards and cash incentive awards will become fully earned and vested immediately if, (i) the 2019 Plan is not an obligation of the successor entity following a change in control or (ii) the 2019 Plan is an obligation of the successor entity following a change in control and the participant incurs a termination of service without cause or for good reason following the change in control. Notwithstanding the immediately preceding sentence, if the vesting of an award is conditioned upon the achievement of performance measures, then such vesting will generally be subject to the following: if, at the time of the change in control, the performance measures are less than 50% attained (pro rata based upon the time of the period through the change in control), the award will become vested and exercisable on a fractional basis with the numerator being equal to the percentage of attainment and the denominator being 50%; and if, at the time of the change in control, the performance measures are at least 50% attained (pro rata based upon the time of the period through the change in control), the award will become fully earned and vested immediately upon the change in control.

Awards of restricted stock under the 2019 Plan generally entitle holders to voting and dividend rights upon grant and are subject to forfeiture until certain restrictions have lapsed including employment for a specific period. Awards of restricted stock units under the 2019 Plan are also subject to forfeiture until certain restrictions have lapsed including employment for a specific period, but do not entitle holders to voting rights until the restricted period ends and shares are transferred in connection with the units.

There were 293,073 and 267,805 restricted stock units issued under the 2019 Plan during the three months ended March 31, 2026, and March 31, 2025, respectively. Compensation expense is recognized over the vesting period of the restricted stock units based on the market value of the award on the issue date. Total compensation cost, including related dividend equivalent expense, that has been recorded for the 2019 Plan was $1.5 million for the three months ended March 31, 2026, and $1.4 million for the three months ended March 31, 2025. The tax benefit recorded was $385,000 and $350,000 for the three months ended March 31, 2026 and March 31, 2025, respectively.

A summary of changes in the Company’s unvested restricted awards for the three months ended March 31, 2026, is as follows:

March 31, 2026

Weighted

Restricted

Average

Stock Shares

Grant Date

  ​ ​ ​

and Units

  ​ ​ ​

Fair Value

Unvested at January 1

812,179

$

16.31

Granted

293,073

20.67

Vested

(239,652)

17.61

Unvested at March 31

865,600

$

17.43

Total unrecognized compensation cost of restricted awards was $9.2 million as of March 31, 2026, which is expected to be recognized over a weighted-average period of 2.25 years.

29

Table of Contents

Note 10 – Earnings Per Share

The earnings per share, both basic and diluted, are as follows:

Three Months Ended March 31, 

  ​ ​ ​

2026

  ​ ​ ​

2025

  ​ ​ ​

  ​ ​ ​

Basic earnings per share:

Weighted-average common shares outstanding

52,450,306

44,967,726

Net income

$

25,585

$

19,830

Basic earnings per share

$

0.49

$

0.44

Diluted earnings per share:

Weighted-average common shares outstanding

52,450,306

44,967,726

Dilutive effect of unvested restricted awards 1

852,766

753,379

Diluted average common shares outstanding

53,303,072

45,721,105

Net Income

$

25,585

$

19,830

Diluted earnings per share

$

0.48

$

0.43

1 Includes the common stock equivalents for restricted share rights that are dilutive.

Note 11 Regulatory & Capital Matters

The Bank is subject to the risk-based capital regulatory guidelines, which include the methodology for calculating the risk-weighted Bank assets, developed by the Office of the Comptroller of the Currency (the “OCC”) and the other bank regulatory agencies. In connection with the current risk-based capital regulatory guidelines, the Bank’s Board of Directors has established an internal guideline requiring the Bank to maintain a Tier 1 leverage capital ratio at or above eight percent (8%) and a total risk-based capital ratio at or above twelve percent (12%). At March 31, 2026, the Bank exceeded those thresholds.

At March 31, 2026, the Bank’s Tier 1 capital leverage ratio was 12.09%, an increase of 60 basis points from December 31, 2025, and is above the 8.00% Board of Directors’ guideline. The Bank’s total capital ratio was 14.88%, an increase of 66 basis points from December 31, 2025, and also above the Board of Directors’ guideline of 12.00%.

Bank holding companies are generally required to maintain minimum levels of capital in accordance with capital guidelines implemented by the Board of Governors of the Federal Reserve System. The general bank and holding company capital adequacy guidelines are shown in the accompanying table, as are the capital ratios of the Company and the Bank, as of March 31, 2026, and December 31, 2025.

The Basel III Rules are applicable to all banking organizations that are subject to minimum capital requirements, including federal and state banks and savings and loan associations, as well as to bank and savings and loan holding companies, other than “small bank holding companies,” which are generally holding companies with consolidated assets of less than $3.0 billion. A detailed discussion of the Basel III Rules is included in Part I, Item 1 of the Company’s Form 10-K for the year ended December 31, 2025, under the heading “Supervision and Regulation.”

At March 31, 2026, and December 31, 2025, Old Second Bancorp, Inc. and its bank subsidiary exceeded the regulatory minimums and Old Second National Bank met the regulatory definition of “well capitalized” based on the most recent regulatory definition.

30

Table of Contents

Capital levels and industry defined regulatory minimum required levels are as follows:

Minimum Capital

Well Capitalized

Adequacy with Capital

Under Prompt Corrective

Actual

Conservation Buffer, if applicable1

Action Provisions2

  ​ ​ ​

Amount

  ​ ​ ​

Ratio

  ​ ​ ​

Amount

  ​ ​ ​

Ratio

  ​ ​ ​

Amount

  ​ ​ ​

Ratio

March 31, 2026

Common equity tier 1 capital to risk weighted assets

Consolidated

$

775,165

13.13

%

$

413,264

7.00

%

N/A

N/A

Old Second National Bank

814,473

13.80

413,138

7.00

$

383,629

6.50

%

Total capital to risk weighted assets

Consolidated

923,600

15.64

620,064

10.50

N/A

N/A

Old Second National Bank

877,909

14.88

619,492

10.50

589,993

10.00

Tier 1 capital to risk weighted assets

Consolidated

800,165

13.55

501,949

8.50

N/A

N/A

Old Second National Bank

814,473

13.80

501,668

8.50

472,158

8.00

Tier 1 capital to average assets

Consolidated

800,165

11.88

269,416

4.00

N/A

N/A

Old Second National Bank

814,473

12.09

269,470

4.00

336,837

5.00

December 31, 2025

Common equity tier 1 capital to risk weighted assets

Consolidated

$

774,990

12.99

%

$

417,624

7.00

%

N/A

N/A

Old Second National Bank

785,569

13.17

417,539

7.00

$

387,714

6.50

%

Total capital to risk weighted assets

Consolidated

922,259

15.46

626,373

10.50

N/A

N/A

Old Second National Bank

847,838

14.22

626,041

10.50

596,229

10.00

Tier 1 capital to risk weighted assets

Consolidated

799,990

13.41

507,078

8.50

N/A

N/A

Old Second National Bank

785,569

13.17

507,011

8.50

477,187

8.00

Tier 1 capital to average assets

Consolidated

799,990

11.70

273,501

4.00

N/A

N/A

Old Second National Bank

785,569

11.49

273,479

4.00

341,849

5.00

1 Amounts are shown inclusive of a capital conservation buffer of 2.50%.

2 The prompt corrective action provisions are only applicable at the Bank level. The Bank exceeded the general minimum regulatory requirements to be considered “well capitalized.”

Dividend Restrictions

In addition to the above requirements, banking regulations and capital guidelines generally limit the amount of dividends that may be paid by a bank without prior regulatory approval. Under these regulations, the amount of dividends that may be paid in any calendar year is limited to the current year’s profits, combined with the retained profit of the previous two years, subject to the capital requirements described above. As of March 31, 2026, the Bank had capacity to pay dividends of $85.3 million to the Company without prior regulatory approval. Pursuant to the Basel III rules, the Bank must keep a capital conservation buffer of 2.50% above the regulatory minimum capital requirements, which must consist entirely of Common Equity Tier 1 capital in order to avoid additional limitations on capital distributions and certain other payments.

31

Table of Contents

Note 12 Fair Value Measurements

Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. The fair value hierarchy established by the Company also requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. Three levels of inputs that may be used to measure fair value are:

Level 1:  Quoted prices (unadjusted) for identical assets or liabilities in active markets that the Company has the ability to access as of the measurement date.

Level 2:  Significant observable inputs other than Level 1 prices, such as quoted prices for similar assets or liabilities, quoted prices in markets that are not active, and other inputs that are observable or can be corroborated by observable market data.

Level 3:  Significant unobservable inputs that reflect a company’s own view about the assumptions that market participants would use in pricing an asset or liability.

There were no transfers between levels during the three-month period ended March 31, 2026 and March 31, 2025.

The Company has certain assets and liabilities measured at fair value. The majority of those assets and liabilities are measured using Level 2 measurement methods. The following is a description of the techniques used to measure all assets and liabilities using Level 2 techniques at fair value as of March 31, 2026, and December 31, 2025:

Government-sponsored agency debt securities are primarily priced using available market information through processes such as benchmark spreads, market valuations of like securities, like securities groupings and matrix pricing.
Other government-sponsored agency securities, mortgage-backed securities (“MBS”), collateralized mortgage obligations (“CMO”), and some of the actively traded real estate mortgage investment conduits and collateralized mortgage obligations are priced using available market information including benchmark yields, prepayment speeds, spreads, volatility of similar securities and trade date.
State and political subdivisions are largely grouped by characteristics (e.g., geographical data and source of revenue in trade dissemination systems). Because some securities are not traded daily and due to other grouping limitations, active market quotes are often obtained using benchmarking for like securities. For securities where quoted prices or market prices are not available, fair value is calculated using discounted cash flows or other market indicators (level 3).
Asset-backed collateralized loan obligations (“CLO”), and asset-backed securities (“ABS”) were priced using data from a pricing matrix supported by our bond accounting service provider and are therefore considered Level 2 valuations. For securities where quoted prices or market prices are not available, fair value is calculated using discounted cash flows or other market indicators (level 3).
Residential mortgage loans available for sale in the secondary market are carried at fair market value. The fair value of loans held-for-sale is determined using quoted secondary market prices for similar loans.
Mortgage banking derivatives, e.g., residential mortgage loans with locked interest rates to be sold in the secondary market and forward commitments for the future delivery of mortgage loans to third party investors, as well as forward commitments for future delivery of MBS, are considered derivatives. Fair values are estimated based on observable changes in mortgage interest rates including prices for MBS from the date of the commitment and do not typically involve significant judgments by management.
The fair value of mortgage servicing rights is based on a valuation model that calculates the present value of estimated net servicing income. The valuation model incorporates assumptions that market participants would use in estimating future net servicing income to derive the resultant value. The Company is able to compare the valuation model inputs, such as the discount rate, prepayment speeds, weighted average delinquency and foreclosure/bankruptcy rates to widely available published industry data for reasonableness.
Interest rate swap positions, both assets and liabilities, are based on valuation pricing models using an income approach reflecting readily observable market parameters such as interest rate yield curves.

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Assets and Liabilities Measured at Fair Value on a Recurring Basis:

The tables below present the balance of assets and liabilities at March 31, 2026 and December 31, 2025, respectively, measured by the Company at fair value on a recurring basis:

March 31, 2026

  ​ ​ ​

Level 1

  ​ ​ ​

Level 2

  ​ ​ ​

Level 3

  ​ ​ ​

Total

Assets:

Securities available-for-sale

U.S. Treasury

$

164,986

$

-

$

-

$

164,986

U.S. government agencies

-

68,625

-

68,625

U.S. government agencies mortgage-backed

-

85,210

-

85,210

States and political subdivisions

-

196,420

6,924

203,344

Collateralized mortgage obligations

-

363,331

363,331

Asset-backed securities

-

39,435

5,070

44,505

Collateralized loan obligations

-

184,711

-

184,711

Equity securities

-

731

-

731

Loans held-for-sale

-

4,344

-

4,344

Mortgage servicing rights

-

-

9,579

9,579

Interest rate derivatives 1

-

4,000

-

4,000

Mortgage banking derivatives

-

117

-

117

Total

$

164,986

$

946,924

$

21,573

$

1,133,483

Liabilities:

Interest rate swap agreements, including risk participation agreements

$

-

$

821

$

-

$

821

Total

$

-

$

821

$

-

$

821

1 Interest rate derivatives include interest rate swaps, a rate cap and risk participation agreements.

December 31, 2025

  ​ ​ ​

Level 1

  ​ ​ ​

Level 2

  ​ ​ ​

Level 3

  ​ ​ ​

Total

Assets:

Securities available-for-sale

U.S. Treasury

$

165,860

$

-

$

-

$

165,860

U.S. government agencies

-

29,176

-

29,176

U.S. government agencies mortgage-backed

-

88,780

-

88,780

States and political subdivisions

-

199,428

6,947

206,375

Collateralized mortgage obligations

-

359,305

-

359,305

Asset-backed securities

-

40,966

4,850

45,816

Collateralized loan obligations

-

194,464

-

194,464

Equity securities

-

747

-

747

Loans held-for-sale

-

3,645

-

3,645

Mortgage servicing rights

-

-

9,459

9,459

Interest rate derivatives 1

-

4,321

-

4,321

Mortgage banking derivatives

-

31

-

31

Total

$

165,860

$

920,863

$

21,256

$

1,107,979

Liabilities:

Interest rate swap agreements, including risk participation agreements

$

-

$

1,157

$

-

$

1,157

Total

$

-

$

1,157

$

-

$

1,157

1 Interest rate derivatives include interest rate swaps, a rate cap and risk participation agreements.

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Table of Contents

The changes in Level 3 assets and liabilities measured at fair value on a recurring basis are as follows:

Three Months Ended March 31, 2026

Securities available-for-sale

States and

Mortgage

Asset-backed

Political

Servicing

  ​ ​

Securities

Subdivisions

  ​ ​

Rights

Beginning balance January 1, 2026

$

4,850

$

6,947

$

9,459

Transfers out of Level 3

-

-

-

Total gains or losses

Included in earnings

-

-

2

Included in other comprehensive income

7

(23)

-

Purchases, issuances, sales, and settlements

Purchases

474

-

-

Issuances

-

-

272

Settlements

(261)

-

(154)

Ending balance March 31, 2026

$

5,070

$

6,924

$

9,579

Three Months Ended March 31, 2025

Securities available-for-sale

States and

Mortgage

Asset-backed

Political

Servicing

  ​ ​ ​

Securities

Subdivisions

  ​ ​ ​

Rights

  ​ ​ ​

Beginning balance January 1, 2025

$

3,254

$

11,896

$

10,374

Transfers out of Level 3

-

-

-

Total gains or losses

Included in earnings

-

-

(488)

Included in other comprehensive income

(36)

(466)

-

Purchases, issuances, sales, and settlements

Purchases

461

-

-

Issuances

-

-

134

Settlements

(96)

(42)

(82)

Ending balance March 31, 2025

$

3,583

$

11,388

$

9,938

The following table and commentary present quantitative and qualitative information about Level 3 fair value measurements as of March 31, 2026:

Weighted

Measured at fair value

Significant Unobservable

Average

on a recurring basis:

  ​ ​

Fair Value

  ​ ​

Valuation Methodology

  ​ ​

Inputs

  ​ ​

Range of Input

  ​ ​

of Inputs

States and political subdivisions

$

6,924

Discounted Cash Flow

Discount Rate

3.7 - 3.7%

3.7

%

Liquidity Premium

0.5 - 0.5%

0.5

%

Asset-backed securities

$

5,070

Discounted Cash Flow

Discount Rate

5.3 - 5.3%

5.3

%

Mortgage servicing rights

$

9,579

Discounted Cash Flow

Discount Rate

9.0 - 9.0%

9.0

%

Prepayment Speed

2.5 - 30.7%

7.7

%

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Table of Contents

The following table and commentary present quantitative and qualitative information about Level 3 fair value measurements as December 31, 2025:

Weighted

Measured at fair value

Significant Unobservable

Average

on a recurring basis:

  ​ ​

Fair Value

  ​ ​

Valuation Methodology

  ​ ​

Inputs

  ​ ​

Range of Input

  ​ ​

of Inputs

States and political subdivisions

$

6,947

Discounted Cash Flow

Discount Rate

3.5 - 3.6%

3.5

%

Liquidity Premium

0.5 - 0.5%

0.5

%

Asset-backed securities

$

4,850

Discounted Cash Flow

Discount Rate

4.9 - 4.9%

4.9

%

Mortgage servicing rights

$

9,459

Discounted Cash Flow

Discount Rate

9.0 - 9.0%

9.0

%

Prepayment Speed

0.0 - 33.2%

8.2

%

Assets and Liabilities Measured at Fair Value on a Nonrecurring Basis:

The Company may be required, from time to time, to measure certain other assets at fair value on a nonrecurring basis in accordance with GAAP. These assets consist of individually evaluated loans and OREO. The following is a description of the techniques used to measure these assets using Level 3 techniques at fair value as of March 31, 2026, and December 31, 2025:

The fair value of individually evaluated loans with specific allocations of the allowance for credit losses is essentially based on recent real estate appraisals or the fair value of the collateralized asset. These appraisals may utilize a single valuation approach or a combination of approaches including comparable sales and the income approach. Adjustments are made in the appraisal process by the appraisers to reflect differences between the available comparable sales and income data. Such adjustments are usually significant and typically result in a Level 3 classification of the inputs for determining fair value.
Nonrecurring adjustments to certain commercial and residential real estate properties classified as other real estate owned (“OREO”) are measured at fair value, less costs to sell. Fair values are based on third party appraisals of the property, resulting in a Level 3 classification, or an executed pending sales contract. In cases where the carrying amount exceeds the fair value, less costs to sell, a valuation loss is recognized.

For assets measured at fair value on a nonrecurring basis at March 31, 2026 and December 31, 2025, respectively, the following tables provide the level of valuation assumptions used to determine each valuation and the carrying value of the related assets:

March 31, 2026

  ​ ​ ​

Level 1

  ​ ​ ​

Level 2

  ​ ​ ​

Level 3

  ​ ​ ​

Total

Individually evaluated loans1

$

-

$

-

$

53,473

$

53,473

Other real estate owned, net2

-

-

632

632

Total

$

-

$

-

$

54,105

$

54,105

1 Represents carrying value and related write-downs of loans for which adjustments are substantially based on the appraised value of collateral for collateral-dependent loans, which had a carrying amount of $64.7 million and a valuation allowance of $11.2 million, resulting in an increase of specific allocations within the allowance for credit losses on loans of $4.8 million for the three months ended March 31, 2026.

2 OREO is measured at the lower of carrying or fair value less costs to sell, and had a net carrying amount of $632,000 at March 31, 2026, which is the outstanding balance of $632,000. There was no valuation allowance at March 31, 2026.

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December 31, 2025

  ​ ​ ​

Level 1

  ​ ​ ​

Level 2

  ​ ​ ​

Level 3

  ​ ​ ​

Total

Individually evaluated loans1

$

-

$

-

$

34,430

$

34,430

Other real estate owned, net2

-

-

1,427

1,427

Total

$

-

$

-

$

35,857

$

35,857

1 Represents carrying value and related write-downs of loans for which adjustments are substantially based on the appraised value of

collateral for collateral-dependent loans and to a lesser extent the discounted cash flow, which had a carrying amount of $40.9 million and a valuation allowance of $6.4 million, resulting in a decrease of specific allocations within the allowance for credit losses on loans of $747,000 for the year December 31, 2025.

2 OREO is measured at the lower of carrying or fair value less costs to sell, and had a net carrying amount of $1.4 million at December 31, 2025, which is made up of the outstanding balance of $2.1 million, net of a valuation allowance of $632,000.

The Company has estimated the fair values of these assets based primarily on Level 3 inputs. OREO and individually evaluated loans are generally valued using the fair value of collateral provided by third party appraisals. These valuations include assumptions related to cash flow projections, discount rates, and recent comparable sales. The numerical ranges of unobservable inputs for these valuation assumptions are not meaningful.

Note 13 – Fair Values of Financial Instruments

The carrying amount and estimated fair values of financial instruments were as follows:

March 31, 2026

Carrying

Fair

  ​ ​ ​

Amount

  ​ ​ ​

Value

  ​ ​ ​

Level 1

  ​ ​ ​

Level 2

  ​ ​ ​

Level 3

Financial assets:

Cash and due from banks

$

48,100

$

48,100

$

48,100

$

-

$

-

Interest earning deposits with financial institutions

67,627

67,627

67,627

-

-

Securities available-for-sale

1,115,443

1,115,443

164,986

938,463

11,994

FHLBC and FRBC stock

31,350

31,350

-

31,350

-

Loans held-for-sale

4,344

4,344

-

4,344

-

Net loans

5,113,111

5,072,088

-

-

5,072,088

Mortgage servicing rights

9,579

9,579

-

-

9,579

Interest rate swap and rate cap agreements

3,975

3,975

-

3,975

-

Interest rate lock commitments and forward contracts

117

117

-

117

-

Interest receivable on securities and loans

29,562

29,562

-

29,562

-

Financial liabilities:

Noninterest bearing deposits

$

1,755,548

$

1,755,548

$

1,755,548

$

-

$

-

Interest bearing deposits

3,809,451

3,801,984

-

3,801,984

-

Securities sold under repurchase agreements

23,130

23,130

-

23,130

-

Other short-term borrowings

200,000

200,000

-

200,000

-

Junior subordinated debentures

25,774

21,907

-

21,907

-

Subordinated debentures

59,574

57,774

-

57,774

-

Note payable and other borrowings

14,837

14,982

-

14,982

-

Interest rate swap and rate cap agreements

808

808

-

808

-

Interest payable on deposits and borrowings

5,184

5,184

-

5,184

-

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Table of Contents

December 31, 2025

Carrying

Fair

  ​ ​ ​

Amount

  ​ ​ ​

Value

  ​ ​ ​

Level 1

  ​ ​ ​

Level 2

  ​ ​ ​

Level 3

Financial assets:

Cash and due from banks

$

51,665

$

51,665

$

51,665

$

-

$

-

Interest earning deposits with financial institutions

72,360

72,360

72,360

-

-

Securities available-for-sale

1,090,523

1,090,523

165,860

912,866

11,797

FHLBC and FRBC stock

32,025

32,025

-

32,025

-

Loans held-for-sale

3,645

3,645

-

3,645

-

Net loans

5,179,830

5,032,472

-

-

5,032,472

Mortgage servicing rights

9,459

9,459

-

-

9,459

Interest rate swap and rate cap agreements

4,298

4,298

-

4,298

-

Interest rate lock commitments and forward contracts

31

31

-

31

-

Interest receivable on securities and loans

30,344

30,344

-

30,344

-

Financial liabilities:

Noninterest bearing deposits

$

1,739,117

$

1,739,117

$

1,739,117

$

-

$

-

Interest bearing deposits

3,856,952

3,850,530

-

3,850,530

-

Securities sold under repurchase agreements

23,769

23,769

-

23,769

-

Other short-term borrowings

215,000

215,000

-

215,000

-

Junior subordinated debentures

25,774

21,522

-

21,522

-

Subordinated debentures

59,552

57,973

-

57,973

-

Note payable and other borrowings

14,825

15,049

-

15,049

-

Interest rate swap and rate cap agreements

1,143

1,143

-

1,143

-

Interest payable on deposits and borrowings

5,451

5,451

-

5,451

-

Note 14 – Derivatives, Hedging Activities and Financial Instruments with Off-Balance Sheet Risk

Risk Management Objective of Using Derivatives

The Company is exposed to certain risk arising from both its business operations and economic conditions. The Company principally manages its exposures to a wide variety of business and operational risks through management of its core business activities. The Company manages economic risks, including interest rate, liquidity, and credit risk, primarily by managing the amount, sources, and duration of its assets and liabilities and the use of derivative financial instruments. Specifically, the Company enters into derivative financial instruments to manage exposures that arise from business activities that result in the receipt or payment of future known and uncertain cash amounts, the value of which are determined by interest rates. The Company’s derivative financial instruments are used to manage differences in the amount, timing, and duration of the Company’s known or expected cash receipts and its known or expected cash payments principally related to the Company’s loan portfolio.

Cash Flow Hedges of Interest Rate Risk

The Company’s objectives in using interest rate derivatives are to add stability to interest income and expense and to manage its exposure to interest rate movements. To accomplish this objective, the Company primarily uses interest rate swaps as part of its interest rate risk management strategy. The aggregate fair value of the swaps is recorded in other assets or other liabilities with changes in fair value recorded in other comprehensive income, net of tax. The amount included in other comprehensive income would be reclassified to current earnings should all or a portion of the hedge no longer be considered effective. For derivatives designated and that qualify as cash flow hedges of interest rate risk, the gain or loss on the derivative is recorded in accumulated other comprehensive income and subsequently reclassified into interest income or interest expense in the same period(s) during which the hedged transaction affects earnings. Amounts reported in accumulated other comprehensive income related to derivatives will be reclassified to interest income or expense as interest payments are received on the variable rate loan pools or paid on the Company’s fixed-rate borrowings.

There are no interest rate swaps as of March 31, 2026 and December 31, 2025, designated as cash flow hedges of certain variable rate commercial and commercial real estate loan pools. All of the interest rate swap cash flow hedges on loans held in the first quarter of 2025 matured during the third quarter of 2025.

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Table of Contents

An interest rate swap with a notional amount of $25.8 million as of March 31, 2026 and December 31, 2025, is designated as a cash flow hedge of junior subordinated debentures and was executed to pay fixed and receive variable rate cash flows. The hedge was determined to be effective during all periods presented and the Company expects the hedge to remain effective during the remaining terms of the swap.

During the next twelve months, the Company estimates that an additional $285,000 will be reclassified as an increase to interest expense.

Non-designated Hedges

Derivatives not designated as hedges are not speculative and result from a service the Company provides to certain customers. The Company executes interest rate swaps and rate cap agreements with commercial banking customers to facilitate their respective risk management strategies. The notional amounts of interest rate swaps with its loan customers as of March 31, 2026 and December 31, 2025 were $123.3 million and $125.8 million, respectively. Those interest rate swaps and rate cap agreements are simultaneously hedged by offsetting derivatives that the Company executes with a third party, such that the Company minimizes its net risk exposure resulting from such transactions. As the interest rate derivatives associated with this program do not meet the strict hedge accounting requirements, changes in the fair value of both the customer derivatives and the offsetting derivatives are recognized directly in earnings.

At March 31, 2026, the Company had $290,000 of cash collateral pledged with one correspondent financial institution and held $3.7 million of cash pledged from one correspondent financial institution to support the interest rate swap activity during 2026. At December 31, 2025, the Company had $660,000 of cash collateral pledged with one correspondent financial institution and held $3.5 million of cash pledged from one correspondent financial institution to support the interest rate swap activity during 2025. No investment securities were required to be pledged to any correspondent financial institution during the first three months of 2026 or during 2025. The Company offsets derivative assets and liabilities that are subject to a master netting arrangement.

The Company also grants mortgage loan interest rate lock commitments to borrowers, subject to normal loan underwriting standards. The interest rate risk associated with these loan interest rate lock commitments is managed with contracts for future deliveries of loans as well as selling forward mortgage-backed securities contracts. Loan interest rate lock commitments generally have fixed expiration dates or other termination clauses and may require payment of a fee. Since many of the commitments are expected to expire without being drawn upon, the total commitment amounts do not necessarily represent future cash requirements. The notional amount of these commitments at March 31, 2026 and December 31, 2025 was $29.2 million and $14.8 million, respectively. Commitments to originate residential mortgage loans held-for-sale and forward commitments to sell residential mortgage loans or forward MBS contracts are considered derivative instruments and changes in the fair value are recorded to mortgage banking revenue. Fair values are estimated based on observable changes in mortgage interest rates including mortgage-backed securities prices from the date of the commitment.

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Table of Contents

The table below presents the fair value of the Company’s derivative financial instruments as well as their classification on the Consolidated Balance Sheets as of March 31, 2026 and December 31, 2025:

Fair Value of Derivative Instruments

March 31, 2026

No. of Trans.

Notional Amount $

Balance Sheet Location

Fair Value $

Balance Sheet Location

Fair Value $

Derivatives designated as hedging instruments

Interest rate swap agreements

1

25,774

Other Assets

3,167

Other Liabilities

-

Total derivatives designated as hedging instruments

3,167

-

Derivatives not designated as hedging instruments

Interest rate swaps with commercial loan customers

11

123,253

Other Assets

808

Other Liabilities

808

Interest rate lock commitments and forward contracts

66

29,220

Other Assets

117

Other Liabilities

-

Other contracts

5

62,945

Other Assets

25

Other Liabilities

13

Total derivatives not designated as hedging instruments

950

821

December 31, 2025

No. of Trans.

Notional Amount $

Balance Sheet Location

Fair Value $

Balance Sheet Location

Fair Value $

Derivatives designated as hedging instruments

Interest rate swap agreements

1

25,774

Other Assets

3,155

Other Liabilities

-

Total derivatives designated as hedging instruments

3,155

-

Derivatives not designated as hedging instruments

Interest rate swaps with commercial loan customers and rate cap

12

125,808

Other Assets

1,143

Other Liabilities

1,143

Interest rate lock commitments and forward contracts

40

14,790

Other Assets

31

Other Liabilities

-

Other contracts

5

63,080

Other Assets

23

Other Liabilities

14

Total derivatives not designated as hedging instruments

1,197

1,157

Disclosure of the Effect of Fair Value and Cash Flow Hedge Accounting

The fair value and cash flow hedge accounting related to derivatives covered under ASC Subtopic 815-20 impacted Accumulated Other Comprehensive Income (“AOCI”) and the Income Statement. The gain recognized in AOCI on derivatives designated as hedging instruments totaled $2.3 million as of March 31, 2026 and $1.6 million as of March 31, 2025. The amount of the gain reclassified from AOCI to net interest income on the Income Statement was $71,000 for the three months ended March 31, 2026, and the amount of the loss reclassified from AOCI was $579,000 for the three months ended March 31, 2025.

Credit-risk-related Contingent Features

For derivative transactions involving counterparties who are lending customers of the Company, the derivative credit exposure is managed through the normal credit review and monitoring process, which may include collateralization, financial covenants and/or financial guarantees of affiliated parties. Agreements with such customers require that losses associated with derivative transactions receive payment priority from any funds recovered should a customer default and ultimate disposition of collateral or guarantees occur.

Credit exposure to broker/dealer counterparties is managed through agreements with each derivative counterparty that require collateralization of fair value gains owed by such counterparties. Some small degree of credit exposure exists due to timing differences between when a gain may occur and the subsequent point in time that collateral is delivered to secure that gain. This is monitored by the Company and procedures are in place to minimize this exposure. Such agreements also require the Company to collateralize counterparties in circumstances wherein the fair value of the derivatives results in loss to the Company.

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Table of Contents

Other provisions of such agreements include the definition of certain events that may lead to the declaration of default and/or the early termination of the derivative transaction(s):

If the Company either defaults or is capable of being declared in default on any of its indebtedness (exclusive of deposit obligations), then the Company could also be declared in default on its derivative obligations.
If a merger occurs that materially changes the Company's creditworthiness in an adverse manner.
If certain specified adverse regulatory actions occur, such as the issuance of a Cease and Desist Order, or citations for actions considered Unsafe and Unsound or that may lead to the termination of deposit insurance coverage by the FDIC.

The Bank also issues letters of credit, which are conditional commitments that guarantee the performance of a customer to a third party. The credit risk involved and collateral obtained in issuing letters of credit are essentially the same as that involved in extending loan commitments to our customers. In addition to customer-related commitments, the Company is responsible for letters of credit commitments that relate to properties held in OREO. The following table represents the Company’s contractual commitments due to letters of credit as of March 31, 2026 and December 31, 2025.

The following table is a summary of letter of credit commitments:

March 31, 2026

December 31, 2025

  ​ ​ ​

Fixed

  ​ ​ ​

Variable

  ​ ​ ​

Total

  ​ ​ ​

Fixed

  ​ ​ ​

Variable

  ​ ​ ​

Total

  ​

Letters of credit:

Borrower:

Financial standby

$

55

$

29,114

$

29,169

$

118

$

26,769

$

26,887

Performance standby

565

6,353

6,918

512

8,666

9,178

620

35,467

36,087

630

35,435

36,065

Non-borrower:

Performance standby

-

-

-

-

-

-

Total letters of credit

$

620

$

35,467

$

36,087

$

630

$

35,435

$

36,065

Unused loan commitments

$

174,456

$

579,377

$

753,833

$

174,479

$

592,658

$

767,137

As of March 31, 2026, the Company evaluated current market conditions, including any impacts related to market interest rate changes and unused line of credit utilization trends during the first quarter of 2026, and based on that analysis under the CECL methodology, the Company determined credit losses related to unfunded commitments totaled $2.0 million. The resultant decrease in the ACL for unfunded commitments of $101,000 for the first three months of 2026 from $2.1 million as of December 31, 2025 was primarily driven by adjustments to historical benchmark assumptions, such as the funding rates and the period used to forecast those rates within the ACL calculation. The Company will continue to assess the credit risk at least quarterly, and adjust the allowance for unfunded commitments, which is carried within other liabilities on our Consolidated Balance Sheets, as needed, with the appropriate offsetting entry to the provision for credit losses on our Consolidated Statements of Income.

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Table of Contents

Note 15 – Segment Information

Various identifiable operating segments provide a variety of revenue streams including loans, deposits, and wealth management services. The Company’s Chief Operating Decision Maker (CODM) is the Chief Financial Officer.

Through our wholly-owned subsidiary, the Bank, we offer a wide variety of community banking services primarily throughout the Chicagoland area, including commercial and consumer lending and deposit services, and a wide array of wealth management services. The accounting policies for the services discussed here are the same as those described in Note 1: Summary of Significant Accounting Policies.  We earn interest income on portfolio loans, fee income on loan originations and commitments, fees charged on certain deposit accounts, as well as fees related to wealth management services.

Although information is available on each of the individual revenue streams, the CODM manages, allocates resources, and evaluates performance on a company-wide basis. The CODM uses consolidated net income to evaluate the financial performance of the Company’s business along with budget to actual results in assessing the Company’s performance and in determining the allocation of resources whether it be to reinvest in the Company or deploy capital in order to maximize shareholder value. The CODM uses consolidated net income and return on average assets to benchmark the Company against competitors as well as against prior periods.

On a regular basis the CODM is provided consolidated income and expense, assets, liabilities, and equity, in the same manner that is presented publicly on the Consolidated Statements of Income and Consolidated Balance Sheets, to assess performance and allocate resources throughout the Company. Further, additional internal financial information is provided to the CODM in order to assess credit quality in each of our lending segments. Accordingly, the Company has determined that it has only one reportable segment, Community Banking.

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Item 2.Management’s Discussion and Analysis of Financial Condition and Results of Operations

Overview

The following discussion provides additional information regarding our operations for the three months ended March 31, 2026, compared to the three months ended March 31, 2025, and our financial condition at March 31, 2026, compared to December 31, 2025. This discussion should be read in conjunction with our consolidated financial statements as well as the financial and statistical data appearing elsewhere in this report and our Form 10-K for the year ended December 31, 2025. The results of operations for the three months ended March 31, 2026 are not necessarily indicative of future results. Dollar amounts presented in the following tables are in thousands, except per share data, and March 31, 2026 and 2025 amounts are unaudited. Certain items in prior periods have been reclassified to conform to the current presentation.

In this report, unless the context suggests otherwise, references to the “Company,” “we,” “us,” and “our” mean the combined business of Old Second Bancorp, Inc. and its subsidiary bank, Old Second National Bank (the “Bank”).

We have made, and will continue to make, various forward-looking statements with respect to financial and business matters. Comments regarding our business that are not historical facts are considered forward-looking statements that involve inherent risks and uncertainties. Actual results may differ materially from those contained in these forward-looking statements. For additional information regarding our cautionary disclosures, see the “Cautionary Note Regarding Forward-Looking Statements” on page 3 of this report.

Business Overview

The Company is a bank holding company headquartered in Aurora, Illinois. Through our wholly-owned subsidiary bank, Old Second National Bank, a national banking organization also headquartered in Aurora, Illinois (the “Bank”), we offer a wide range of financial services through our 55 banking centers located in Cook, DeKalb, DuPage, Kane, Kendall, LaSalle and Will counties in Illinois. These banking centers offer access to a full range of traditional retail and commercial banking services including treasury management operations as well as fiduciary and wealth management services. We focus our business on establishing and maintaining relationships with our clients while maintaining a commitment to provide for the financial services needs of the communities in which we operate. We emphasize relationships with individual customers as well as small to medium-sized businesses throughout our market area. We also have extensive wealth management services, which include a registered investment advisory platform in addition to trust administration and trust services related to personal and corporate trusts and employee benefit plan administration services.

On July 1, 2025, we completed our previously announced acquisition of Bancorp Financial, Inc. (“Bancorp Financial”), pursuant to the agreement and plan of merger dated February 24, 2025. At the effective time of the acquisition, Bancorp Financial merged with and into the Company, with the Company continuing as the surviving corporation. Immediately following the merger, Evergreen Bank Group (“Evergreen”), an Illinois-chartered banking corporation and wholly-owned subsidiary of Bancorp Financial, merged with and into Old Second National Bank, with the Bank continuing as the surviving bank. Under the terms of the merger agreement, each share of Bancorp Financial common stock outstanding immediately prior to the effective time was converted into the right to receive 2.5814 shares of Old Second common stock and $15.93 in cash, without interest, with cash paid in lieu of any fractional shares.

As of July 1, 2025, Bancorp Financial had approximately $1.43 billion of total assets, $1.20 billion of total loans, and $1.23 billion of total deposits. The consideration paid totaled $189.4 million and consisted of 7.9 million shares of Old Second common stock and $48.9 million in cash. The systems conversion was successfully completed in October 2025.

Our results of operations depend generally on net interest income, which is the difference between interest income from interest-earning assets and interest expense on interest-bearing liabilities. Net interest income is affected by regulatory, economic and competitive factors that influence interest rates, loan demand and deposit flows. In addition, we are subject to interest rate risk to the degree that our interest-earning assets mature or reprice at different times, or at different speeds, than our interest-bearing liabilities. Our results of operations are also affected by noninterest income, such as service charges, wealth management fees, loan fees, gains from the sale of newly originated loans, gains or losses on investments and certain other noninterest related items. Our principal operating expenses, aside from interest expense, consist of compensation and employee benefits, occupancy costs, professional fees, data processing expenses and provision for credit losses.

 

We are significantly impacted by prevailing economic conditions, including federal monetary and fiscal policies, and federal regulations of financial institutions. Deposit balances are influenced by numerous factors such as competing investments, the level of income and the personal rate of savings within our market areas. Factors influencing lending activities include the demand for housing and the interest rate pricing competition from other lending institutions.

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As of March 31, 2026, all of our capital ratios were in excess of all regulatory requirements. While we believe that we have sufficient capital to withstand an extended economic recession, our reported and regulatory capital ratios could be adversely impacted by credit losses.

Financial Overview

Net income for the first quarter of 2026 was $25.6 million, or $0.48 per diluted share, compared to $28.8 million, or $0.54 per diluted share, for the fourth quarter of 2025, and $19.8 million, or $0.43 per diluted share, for the first quarter of 2025. Net income increased compared to the prior year like quarter, primarily due to the Bancorp Financial acquisition and the resulting growth in net interest income. Variances included an increase of $24.8 million in interest and dividend income and a $2.4 million increase in noninterest income, partially offset by a $6.5 million increase in interest expense, a $7.1 million increase in provision for credit losses, a $5.7 million increase in noninterest expense, and a $2.1 million increase in provision for income taxes. Net income in the first quarter of 2026 was negatively impacted by provision for credit losses of $9.5 million, compared to $3.0 million and $2.4 million recorded in the fourth quarter of 2025 and first quarter of 2025, respectively. Adjusted net income, a non-GAAP financial measure that excludes mortgage servicing rights mark to market gains or losses, net securities gains or losses, and acquisition related costs, net of gains on branch sales, as applicable, was $26.0 million for the first quarter of 2026, compared to $30.8 million for the fourth quarter of 2025, and $20.6 million for the first quarter of 2025.

See the discussion entitled “Non-GAAP Financial Measures” on page 45, as well as the table below, which provides a reconciliation of this non-GAAP measure to the most comparable GAAP equivalents:

Net Income and Earnings Per Share - GAAP and Adjusted

Three Months Ended

March 31, 

December 31, 

March 31, 

  ​ ​ ​

2026

  ​ ​ ​

2025

2025

Income before income taxes (GAAP)

$

34,064

$

39,270

$

26,200

Pre-tax income adjustments:

Securities gains, net

-

(8)

-

MSR losses

152

428

570

Acquisition related costs, net of (gains) losses on branch sales

349

2,296

454

Adjusted net income before taxes

34,565

41,986

27,224

Taxes on adjusted net income

8,604

11,208

6,619

Adjusted net income (non-GAAP)

$

25,961

$

30,778

$

20,605

Basic earnings per share (GAAP)

$

0.49

$

0.55

$

0.44

Diluted earnings per share (GAAP)

0.48

0.54

0.43

Adjusted basic earnings per share (non-GAAP)

0.49

0.59

0.46

Adjusted diluted earnings per share (non-GAAP)

0.49

0.58

0.45

Total average assets

6,859,164

6,960,177

5,673,092

Return on average assets (GAAP)

1.51

%

1.64

%

1.42

%

Adjusted return on average assets (non-GAAP)

1.53

1.75

1.47

The following provides an overview of some of the factors impacting our financial performance for the three-month period ended March 31, 2026, compared to the like period ended March 31, 2025:

Net interest and dividend income was $81.1 million for the first quarter of 2026, compared to $62.9 million for the first quarter of 2025. The increase in net interest and dividend income in the first quarter of 2026 was primarily driven by the acquisition of Bancorp Financial.

We recorded a net provision for credit losses on loans and leases of $9.5 million in the first quarter of 2026, driven by quarterly net charge-offs of $9.8 million. Partially offsetting this expense, we recorded a reversal of $101,000 in our allowance for unfunded commitments in the first quarter of 2026 based on an adjustment of historical benchmark assumptions, such as funding rates and the period used to forecast those rates, within the ACL calculation. We recorded a net provision for credit losses of $2.4 million in the first quarter of 2025.

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Noninterest income was $12.6 million for the first quarter of 2026, compared to $10.2 million for the first quarter of 2025, which is an increase of $2.4 million, or 23.8%. Contributing to the higher noninterest income was a $714,000 increase in other income as a result of powersport and other consumer fee income. Also contributing to the growth in noninterest income during the quarter, compared to the prior year like quarter, were increases in wealth management, residential mortgage banking revenue due to a decrease in MSR mark to market losses, and an increase in the cash surrender value of BOLI as a result of an increase in the market value of our insurance policies due primarily to more favorable market interest rates.

Noninterest expense was $50.2 million for the first quarter of 2026, compared to $44.5 million for the first quarter of 2025, an increase of $5.7 million, or 12.8%. The increase in noninterest expense in the first quarter of 2026, compared to the prior year like quarter, was primarily due to the Bancorp Financial acquisition and the corresponding growth in employees and operations, which resulted in higher salaries and employee benefits, and increases in occupancy, furniture and equipment, computer and data processing, consumer credit expense, and other expense.

We had a provision for income tax expense of $8.5 million for the first quarter of 2026, compared to a provision for income tax expense of $6.4 million for the first quarter of 2025. The effective tax rate for these two periods was 24.9% and 24.3%, respectively.

As of March 31, 2026, total loans decreased by $66.9 million compared to the year ended December 31, 2025, and increased $1.25 billion compared to March 31, 2025. The increase from the prior year like period is primarily driven by the $1.20 billion of loans acquired in our acquisition of Bancorp Financial.

Nonaccrual loans totaled $62.6 million as of March 31, 2026, which is an increase of $14.7 million compared to December 31, 2025, and an increase of $29.2 million compared to March 31, 2025. The increase in nonaccrual loans as of March 31, 2026, compared to December 31, 2025, was primarily due to inflows of $19.7 million on 37 loans, consisting primarily of ten commercial loans totaling $17.3 million. The inflows are partially offset by $3.1 million of paid off nonaccrual loans, and $1.7 million of reduction of principal from payments and partial charge offs.  The increase in nonaccrual loans year over year is partially due to the growth in the loan portfolio due to the Bancorp Financial acquisition, as well as two larger credits which were moved to nonperforming status with partial charge-offs taken in the first quarter of 2026.  Nonperforming loans as a percent of total loans was 1.5% as of March 31, 2026, compared to 1.0% as of December 31, 2025, and 0.9% as of March 31, 2025. Classified assets decreased to $150.1 million as of March 31, 2026, reflecting a decrease of $2.8 million, or 1.8%, from December 31, 2025, and an increase of $61.7 million, or 69.7%, from March 31, 2025.

Critical Accounting Estimates

Our consolidated financial statements are prepared based on the application of accounting policies in accordance with generally accepted accounting principles (“GAAP”) and follow general practices within the banking industry. These policies require reliance on estimates and assumptions which may prove inaccurate or are subject to variations. These estimates, assumptions, and judgments are based on information available as of the date of the consolidated financial statements. Future changes in information may affect these estimates, assumptions, and judgments, which, in turn, may affect amounts reported in the consolidated financial statements. Changes in underlying factors, assumptions, or estimates could have a material impact on our future financial condition and results of operations.

Of the significant accounting policies used in the preparation of our consolidated financial statements, we have identified certain items as critical accounting policies based on the associated estimates, assumptions, judgments and complexity. See “Management’s Discussion and Analysis of Financial Condition and Results of Operations—Critical Accounting Estimates” in our Annual Report on Form 10-K for the year ended December 31, 2025. There have been no material changes to our critical accounting policies or the estimates made pursuant to those policies during the most recent quarter from those disclosed in our 2025 Annual Report Form 10-K.

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Non-GAAP Financial Measures

This report contains references to financial measures that are not defined in GAAP. Such non-GAAP financial measures include the presentation of net interest income and net interest margin on a tax equivalent (“TE”) basis, adjusted net income, adjusted basic and diluted earnings per share, and our adjusted efficiency ratio. Management believes that the presentation of these non-GAAP financial measures (a) provides important supplemental information that contributes to a proper understanding of our operating performance, (b) enables a more complete understanding of factors and trends affecting our business, and (c) allows investors to evaluate our performance in a manner similar to management, the financial services industry, bank stock analysts, and bank regulators. Management uses non-GAAP measures as follows: in the preparation of our operating budgets, monthly financial performance reporting, and in our presentation of our performance to investors. However, we acknowledge that these non-GAAP financial measures have a number of limitations. Limitations associated with non-GAAP financial measures include the risk that persons might disagree as to the appropriateness of items comprising these measures and that different companies might calculate these measures differently. These measures should not be considered an alternative to our GAAP results. A reconciliation of non-GAAP financial measures to the most directly comparable GAAP financial measures is presented below or alongside the first instance where each non-GAAP financial measure is used.

Results of Operations

Overview

Three months ended March 31, 2026 and 2025

Our income before taxes was $34.1 million in the first quarter of 2026, compared to $26.2 million in the first quarter of 2025. Net interest and dividend income increased $18.2 million, and provision for credit losses increased $7.1 million in the first quarter of 2026, compared to the like 2025 quarter. Income before taxes was also affected by a $2.4 million increase in noninterest income and a $5.7 million increase in noninterest expense. The noninterest expense increase of $5.7 million is primarily due to a $2.7 million increase in salary and employee benefits expense primarily attributable to the additional employees retained in the Bancorp Financial acquisition and higher base salary rates, an $823,000 increase in occupancy, furniture and equipment, a $1.0 million increase in computer and data processing, a $1.5 million increase in consumer credit expense, and a $721,000 increase in other expenses, which were all primarily driven by the additional operations assumed from the Bancorp Financial acquisition. Total acquisition costs of $349,000 were recorded as a result of the Bancorp Financial acquisition during the three months ended March 31, 2026. Our net income was $25.6 million, or $0.48 per diluted share, for the first quarter of 2026, compared to net income of $19.8 million, or $0.43 per diluted share, for the first quarter of 2025. The Bank remains well positioned to navigate uncertain macroeconomic conditions. We have proactively addressed interest rate risk, maintained disciplined expense management, and ensured robust daily liquidity oversight. In addition, our liquidity metrics remain solid, and our short-duration securities portfolio provides flexibility for near-term funding requirements.

Net Interest Income

Net interest income, which is our primary source of earnings, is the difference between income earned on interest-earning assets, such as loans and investment securities, accretion income on purchased loans, dividend income earned on certain equity investments, and expense incurred on interest-bearing liabilities, such as deposits and borrowings. Net interest income depends upon the relative mix of interest-earning assets and interest-bearing liabilities, the ratio of interest-earning assets to total assets and of interest-bearing liabilities to total funding sources, and movements in market interest rates. Our net interest income can be significantly influenced by a variety of factors, including overall loan demand, economic conditions, credit risk, the amount of nonearning assets including nonperforming loans and OREO, the amounts of and rates at which assets and liabilities reprice, variances in prepayment of loans and securities, early withdrawal of deposits, exercise of call options on borrowings or securities, a general rise or decline in interest rates, changes in the slope of the yield-curve, and balance sheet growth or contraction.

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Three months ended March 31, 2026 and 2025

Net interest and dividend income was $81.1 million in the first quarter of 2026, compared to $62.9 million in the first quarter of 2025. The $18.2 million increase was driven by a $24.8 million increase in interest and dividend income due to the acquisition of Bancorp Financial. A net increase of $6.5 million in interest expense in the first quarter of 2026 negatively impacted net interest and dividend income compared to the first quarter of 2025, driven by the higher cost deposits and increased short-term borrowing balances driven by the Bancorp Financial acquisition.

The year over year yield increase of 53 basis points on interest earning assets was primarily driven by higher loan balances and higher yielding consumer credits and related accretion on the Bancorp Financial portfolio acquired, as well as planned turnover in our securities portfolio with many older and lower yielding securities maturing and being replaced with higher yielding investments while maintaining the shorter duration portfolio composition. Average balances of loans and loans held for sale increased $1.25 billion in the first quarter of 2026 compared to the prior year like quarter, with a corresponding increase to the tax equivalent yield on the loan portfolio of 48 basis points year over year due to certain portfolios acquired from Bancorp Financial. Average balances of securities available for sale decreased $65.8 million in the first quarter of 2026 compared to the prior year like quarter, but showed an increase to the tax equivalent yield on the securities available for sale portfolio of seven basis points year over year primarily due to variable security rate resets and run-off of lower yielding investments.

The cost of interest bearing deposits increased 24 basis points for the quarter ended March 31, 2026, from 128 basis points for the quarter ended March 31, 2025. A 41-basis point increase in the cost of savings accounts drove a significant portion of the overall increase from the prior year like quarter, primarily due to the higher rate deposit accounts assumed in the Bancorp Financial acquisition. In addition, average time deposits increased $337.3 million due to the Bancorp Financial acquisition; both higher average balances and higher rates offered by Bancorp Financial resulted in a $2.4 million increase in time deposit interest expense. We will continue to control the cost of funds by monitoring market activity as well as allowing previous exception-priced deposits and the brokered CDs acquired from Bancorp Financial to runoff naturally.

The increase of $187.6 million year over year of average FHLB advances was based on daily liquidity needs due to the changes in the funding mix in part due to necessary use of cash on the Bancorp Financial acquisition and was the primary driver of the $1.8 million increase to interest expense on other short-term borrowings. The increase of $14.8 million year over year of average notes payable and other borrowings was due to the FHLB long-term putable advances assumed in the Bancorp Financial acquisition and was the reason for the $155,000 increase to interest expense on notes payable and other borrowings. Subordinated and junior subordinated debt interest expense were essentially flat over each of the periods presented.

Three months ended March 31, 2026 and December 31, 2025

The decreased yield of three basis points on interest earning assets for the three months ended March 31, 2026 as compared to the linked period was primarily driven by the decreased yield on loans coupled with lower average loan balances. Changes in the market interest rate environment impact earning assets at varying intervals depending on the repricing timeline of loans, as well as the securities maturity, paydown and purchase activities.

Average balances of interest bearing deposit accounts have decreased significantly since the fourth quarter of 2025 through the first quarter of 2026, from $3.94 billion to $3.83 billion. Of the $119.2 million decrease in average interest bearing deposit account balances, time deposits accounted for $117.3 million of the decrease as exception priced deposits, mainly time deposits, and brokered deposits from the Bancorp Financial acquisition, run off. The significant time deposit average balance decrease led to the $1.4 million decrease in deposits costs, compared to the prior linked quarter, which accounted for a large majority of the $2.2 million total decrease in deposit costs. As a result, time deposits were the primary driver in the decrease in the costs of interest bearing deposits from 167 basis points for the quarter ended December 31, 2025, to 152 basis points for the quarter ended March 31, 2026.

Borrowing costs increased in the first quarter of 2026, compared to the fourth quarter of 2025. Changes in our borrowing costs are generally driven by fluctuations in balance and related rates on other short-term borrowings, which are overnight FHLB advances; these fluctuations are based on the daily liquidity needs during the period. The increase in borrowing expense over the prior linked period was primarily due to the $29.5 million increase in average balance of other short-term borrowings offset slightly by lower rates.

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Our net interest margin, for both GAAP and tax equivalent (“TE”) presentations, showed noticeable growth over the prior linked quarter period and over the prior year like quarter discussed above. Our net interest margin (GAAP) increased five basis points to 5.12% for the first quarter of 2026, compared to 5.07% for the fourth quarter of 2025, and increased 27 basis points compared to 4.85% for the first quarter of 2025. Our net interest margin (TE) increased five basis points to 5.14% for the first quarter of 2026, compared to 5.09% for the fourth quarter of 2025, and increased 26 basis points compared to 4.88% for the first quarter of 2025. The increase in net interest margin for the first quarter of 2026, compared to the prior linked quarter, was driven by the reduction in the cost of interest bearing liabilities. The net interest margin increased in the first quarter of 2026, compared to the prior year like quarter, was primarily due to the Bancorp Financial acquisition and the resulting increase in loan yields which outpaced the higher cost of deposits. See the discussion entitled “Non-GAAP Financial Measures,” above, and the tables beginning on page 48 that provide a reconciliation of each non-GAAP measure to the most comparable GAAP equivalent.

Analysis of Average Balances,

Tax Equivalent Income / Expense and Rates

(unaudited)

Quarters Ended

March 31, 2026

December 31, 2025

March 31, 2025

Average

Income /

Rate

Average

Income /

Rate

Average

Income /

Rate

Balance

Expense

%

Balance

Expense

%

Balance

Expense

%

Assets

Interest earning deposits with financial institutions

$

67,571

$

549

3.30

$

66,430

$

598

3.57

$

97,645

$

988

4.10

Securities:

Taxable

969,194

8,949

3.74

979,060

9,136

3.70

1,026,233

9,227

3.65

Non-taxable (TE)1

146,299

1,462

4.05

150,573

1,543

4.07

155,024

1,595

4.17

Total securities(TE)1

1,115,493

10,411

3.79

1,129,633

10,679

3.75

1,181,257

10,822

3.72

Dividends from FHLBC and FRBC

31,540

512

6.58

30,085

390

5.14

19,441

473

9.87

Loans and loans held-for-sale1,2

5,207,744

87,194

6.79

5,278,643

90,969

6.84

3,959,073

61,626

6.31

Total interest earning assets

6,422,348

98,666

6.23

6,504,791

102,636

6.26

5,257,416

73,909

5.70

Cash and due from banks

48,252

-

-

52,040

-

-

52,550

-

-

Allowance for credit losses on loans

(71,869)

-

-

(73,718)

-

-

(43,543)

-

-

Other noninterest bearing assets

460,433

-

-

477,064

-

-

406,669

-

-

Total assets

$

6,859,164

$

6,960,177

$

5,673,092

Liabilities and Stockholders' Equity

NOW accounts

$

697,692

$

823

0.48

$

682,729

$

816

0.47

$

628,336

$

629

0.41

Money market accounts

946,075

4,148

1.78

958,672

4,561

1.89

801,178

3,393

1.72

Savings accounts

1,118,979

2,176

0.79

1,123,208

2,529

0.89

940,894

891

0.38

Time deposits

1,062,623

7,217

2.75

1,179,966

8,665

2.91

725,314

4,829

2.70

Interest bearing deposits

3,825,369

14,364

1.52

3,944,575

16,571

1.67

3,095,722

9,742

1.28

Securities sold under repurchase agreements

24,795

50

0.82

23,464

45

0.76

34,529

68

0.80

Other short-term borrowings

189,056

1,791

3.84

159,565

1,644

4.09

1,444

17

4.77

Junior subordinated debentures

25,774

296

4.66

25,774

288

4.43

25,773

288

4.53

Subordinated debt

59,564

546

3.72

59,542

546

3.64

59,478

546

3.72

Notes payable and other borrowings

14,831

155

4.24

14,819

158

4.23

-

-

-

Total interest bearing liabilities

4,139,389

17,202

1.69

4,227,739

19,252

1.81

3,216,946

10,661

1.34

Noninterest bearing deposits

1,738,504

-

-

1,781,374

-

-

1,703,382

-

-

Other liabilities

73,284

-

-

67,078

-

-

69,186

-

-

Stockholders' equity

907,987

-

-

883,986

-

-

683,578

-

-

Total liabilities and stockholders' equity

$

6,859,164

$

6,960,177

$

5,673,092

Net interest income (GAAP)

$

81,144

$

83,051

$

62,904

Net interest margin (GAAP)

5.12

5.07

4.85

Net interest income (TE)1

$

81,464

$

83,384

$

63,248

Net interest margin (TE)1

5.14

5.09

4.88

Interest bearing liabilities to earning assets

64.45

%

64.99

%

61.19

%

1 Represents a non-GAAP financial measure. See the discussion entitled “Reconciliation of Tax-Equivalent Non-GAAP Financial Measures” below that provides a reconciliation of each non-GAAP measure to the most comparable GAAP equivalent. Tax equivalent basis is calculated using a marginal tax rate of 21% in 2026 and 2025, respectively.

2 Interest income from loans is shown on a tax equivalent basis, which is a non-GAAP financial measure, as discussed in the table on page 50, and includes loan fee income of $1.9 million for the first quarter of 2026, loan fee income of $1.9 million for the fourth quarter of 2025, and loan fee income of $545,000 for the first quarter of 2025. Nonaccrual loans are included in the above-stated average balances.

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Table of Contents

Reconciliation of Tax-Equivalent (TE) Non-GAAP Financial Measures

Net interest and dividend income (TE) and net interest income (TE) to average interest earning assets are non-GAAP measures that have been adjusted on a TE basis using a marginal rate of 21% for 2026 and 2025 to compare returns more appropriately on tax-exempt loans and securities to other earning assets. The table below provides a reconciliation of each non-GAAP (TE) measure to the GAAP equivalent for the periods indicated:

Three Months Ended

March 31, 

December 31, 

March 31, 

Net Interest Margin

  ​ ​ ​

2026

  ​ ​ ​

2025

2025

Interest income (GAAP)

$

98,346

$

102,303

$

73,565

Taxable-equivalent adjustment:

Loans

13

9

9

Securities

307

324

335

Interest and dividend income (TE)

98,666

102,636

73,909

Interest expense (GAAP)

17,202

19,252

10,661

Net interest income (TE)

$

81,464

$

83,384

$

63,248

Net interest income (GAAP)

$

81,144

$

83,051

$

62,904

Average interest earning assets

$

6,422,348

$

6,504,791

$

5,257,416

Net interest margin (GAAP)

5.12

%

5.07

%

4.85

%

Net interest margin (TE)

5.14

%

5.09

%

4.88

%

Noninterest Income

Three months ended March 31, 2026 and 2025

The following table details the major components of noninterest income for the periods presented:

March 31, 2026

Noninterest Income

Three Months Ended

Percent Change From

March 31, 

December 31, 

March 31, 

December 31, 

March 31, 

  ​ ​ ​

2026

  ​ ​ ​

2025

  ​ ​ ​

2025

  ​ ​ ​

2025

  ​ ​ ​

2025

 

Wealth management

$

3,383

$

3,537

$

3,089

(4.4)

9.5

Service charges on deposits

3,126

3,125

2,976

0.0

5.0

Residential mortgage banking revenue

Secondary mortgage fees

121

123

73

(1.6)

65.8

MSRs mark to market loss

(152)

(428)

(570)

64.5

(73.3)

Mortgage servicing income

497

444

480

11.9

3.5

Net gain on sales of mortgage loans

555

657

464

(15.5)

19.6

Total residential mortgage banking revenue

1,021

796

447

28.3

128.4

Securities gains, net

-

8

-

N/M

N/M

Change in cash surrender value of BOLI

1,082

834

498

29.7

117.3

Card related income

2,354

2,548

2,241

(7.6)

5.0

Other income

1,664

1,306

950

27.4

75.2

Total noninterest income

$

12,630

$

12,154

$

10,201

3.9

23.8

N/M – Not meaningful.

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Table of Contents

Noninterest income increased $476,000, or 3.9%, in the first quarter of 2026, compared to the fourth quarter of 2025, and increased $2.4 million, or 23.8%, compared to the first quarter of 2025. The increase from the fourth quarter of 2025 was primarily driven by a $225,000 increase in residential mortgage banking revenue mainly due to a $276,000 increase in MSRs mark to market valuations, a $248,000 increase in the cash surrender value of BOLI due to changes in market interest rates, and a $358,000 increase in other income primarily driven by growth in powersport and consumer loan fees provided by the legacy Bancorp Financial loan portfolio. Partially offsetting the increases during the first quarter of 2026, compared to the fourth quarter of 2025, was a $154,000 decrease in wealth management income due to lower insurance – annuities fees, estate fees, and miscellaneous fees, and a $194,000 decrease in card related income due to a reduction in the volume of ATM activity and related fees.

The increase in noninterest income of $2.4 million in the first quarter of 2026, compared to the first quarter of 2025, is primarily due to a $294,000 increase in wealth management income from growth in advisory fees, a $150,000 increase in service charges on deposits, a $584,000 increase in the cash surrender value of BOLI due to changes in market interest rates, and a $574,000 increase in residential mortgage banking revenue mainly due to a $418,000 increase in MSRs mark to market valuations. Also contributing to the increase in noninterest income during the quarter was a $714,000 increase in other income due to powersport and consumer loan fees provided by the legacy Bancorp Financial loan portfolio.

Noninterest Expense

Three months ended March 31, 2026 and 2025

The following table details the major components of noninterest expense for the periods presented:

March 31, 2026

Noninterest Expense

Three Months Ended

Percent Change From

March 31, 

December 31, 

March 31, 

December 31, 

March 31, 

  ​ ​ ​

2026

  ​ ​ ​

2025

  ​ ​ ​

2025

  ​ ​ ​

2025

  ​ ​ ​

2025

 

Salaries

$

21,933

$

22,426

$

18,804

(2.2)

16.6

Officers' incentive

1,652

3,035

2,799

(45.6)

(41.0)

Benefits and other

6,088

5,535

5,390

10.0

12.9

Total salaries and employee benefits

29,673

30,996

26,993

(4.3)

9.9

Occupancy, furniture and equipment expense

5,371

5,092

4,548

5.5

18.1

Computer and data processing

3,375

4,798

2,348

(29.7)

43.7

FDIC insurance

759

720

628

5.4

20.9

Net teller & bill paying

716

701

658

2.1

8.8

General bank insurance

353

354

330

(0.3)

7.0

Amortization of core deposit intangible asset

1,176

1,235

1,037

(4.8)

13.4

Advertising and marketing expense

551

437

229

26.1

140.6

Card related expense

1,519

1,652

1,380

(8.1)

10.1

Professional fees

1,299

1,265

1,095

2.7

18.6

Consumer credit expense

1,522

1,451

25

4.9

5,988.0

Other real estate owned expense, net

(186)

81

1,873

(329.6)

(109.9)

Other expense

4,082

4,153

3,361

(1.7)

21.5

Total noninterest expense

$

50,210

$

52,935

$

44,505

(5.1)

12.8

Efficiency ratio (GAAP)1

52.40

%

53.98

%

56.46

%

Adjusted efficiency ratio (non-GAAP)2

51.70

%

51.28

%

55.48

%

1 The efficiency ratio shown in the table above is a GAAP financial measure calculated as noninterest expense, excluding amortization of core deposits and OREO expenses, divided by the sum of net interest income and total noninterest income less net gains or losses on securities, death benefit realized on BOLI, as applicable, and mark to market gains or losses on MSRs.

2 The adjusted efficiency ratio shown in the table above is a non-GAAP financial measure calculated as noninterest expense, excluding amortization of core deposits, OREO expenses, acquisition expense, net of gains or losses on branch sales, as applicable, divided by the sum of net interest income on a fully tax equivalent basis, total noninterest income less net gains or losses on securities, death benefit realized on BOLI, as applicable, mark to market gains or losses on MSRs, and includes a tax equivalent adjustment on the change in cash surrender value of BOLI. See the discussion entitled “Non-GAAP Financial Measures” above and the table on page 50 that provides a reconciliation of this non-GAAP financial measure to the most comparable GAAP equivalent.

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Table of Contents

Noninterest expense for the first quarter of 2026 decreased $2.7 million, or 5.1%, compared to the fourth quarter of 2025, and increased $5.7 million, or 12.8%, compared to the first quarter of 2025. The decrease in the first quarter of 2026, compared to the fourth quarter of 2025, was driven by a $1.3 million decrease in salaries and employee benefits with decreases reflected primarily in salaries, officer incentive accruals, and insurance premiums. Other decreases include a $1.4 million decrease in computer and data processing expenses due to the timing of costs incurred related to the core system conversion as a result of our acquisition of Bancorp Financial and a $267,000 decrease in net OREO expenses due to a $235,000 gain recorded on the transfer of one property to OREO during the first quarter of 2026.

The year over year increase in noninterest expense is primarily attributable to a $2.7 million increase in salaries and employee benefits, primarily due to the increased workforce from the Bancorp Financial acquisition as well as increases in annual base salary rates and payroll taxes in the first quarter of 2026. Also contributing to the increase was an $823,000 increase in occupancy, furniture and equipment, a $1.0 million increase in computer and data processing expenses, a $1.5 million increase in consumer credit expense, and a $721,000 increase in other expense primarily due to the effect of the Bancorp Financial acquisition and the corresponding growth in expenses. Partially offsetting the year over year increase in noninterest expense was a $2.1 million decrease in net OREO expenses as a majority of OREO properties have been sold since the first quarter of 2025, resulting in a reduction of expenses.

Efficiency Ratio

The efficiency ratio presented above and reconciled below measures how much it costs an institution to generate one dollar of revenue. We utilize this measure in evaluating employee performance incentives as well as in comparison against peer performance, to set and assess operational standards. The following table provides a reconciliation of the non-GAAP efficiency ratio to the most comparable GAAP equivalent.

Reconciliation of Adjusted Efficiency Ratio Non-GAAP Financial Measures

GAAP

Non-GAAP

Three Months Ended

Three Months Ended

March 31, 

December 31, 

March 31, 

March 31, 

December 31, 

March 31, 

2026

2025

2025

2026

2025

2025

Efficiency Ratio / Adjusted Efficiency Ratio

Noninterest expense

$

50,210

$

52,935

$

44,505

$

50,210

$

52,935

$

44,505

Less amortization of core deposit

1,176

1,235

1,037

1,176

1,235

1,037

Less other real estate expense, net 

(186)

81

1,873

(186)

81

1,873

Less acquisition related costs, net of losses on branch sales

N/A

N/A

N/A

349

2,296

454

Noninterest expense less adjustments

$

49,220

$

51,619

$

41,595

$

48,871

$

49,323

$

41,141

Net interest income

$

81,144

$

83,051

$

62,904

$

81,144

$

83,051

$

62,904

Taxable-equivalent adjustment:

Loans

N/A

N/A

N/A

13

9

9

Securities

N/A

N/A

N/A

307

324

335

Net interest income including adjustments

81,144

83,051

62,904

81,464

83,384

63,248

Noninterest income

12,630

12,154

10,201

12,630

12,154

10,201

Less securities gains

-

8

-

-

8

-

Less MSRs mark to market losses

(152)

(428)

(570)

(152)

(428)

(570)

Change in cash surrender value of BOLI

N/A

N/A

N/A

288

222

132

Noninterest income including adjustments

12,782

12,574

10,771

13,070

12,796

10,903

Net interest income including adjustments plus noninterest income including adjustments

$

93,926

$

95,625

$

73,675

$

94,534

$

96,180

$

74,151

Efficiency ratio / Adjusted efficiency ratio

52.40

%

53.98

%

56.46

%

51.70

%

51.28

%

55.48

%

N/A - not applicable

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Table of Contents

Income Taxes

We recorded income tax expense of $8.5 million for the first quarter of 2026 on $34.1 million of pretax income, compared to income tax expense of $10.5 million on $39.3 million of pretax income in the fourth quarter of 2025, and income tax expense of $6.4 million on $26.2 million of pretax income in the first quarter of 2025. Our effective tax rate was 24.9% in the first quarter of 2026, 26.7% for the fourth quarter of 2025, and 24.3% for the first quarter of 2025.

Income tax expense reflected all relevant statutory tax rates and GAAP accounting. There were no significant changes in our ability to utilize our deferred tax assets during the quarter ended March 31, 2026. We had no valuation reserve on the deferred tax assets as of March 31, 2026.

Financial Condition

Total assets decreased $53.5 million to $6.85 billion at March 31, 2026, from $6.90 billion at December 31, 2025, due primarily to the decrease of $66.9 million in total loans. This decrease was partially offset by an increase in securities available-for-sale of $24.9 million. We continue to actively assess potential investment opportunities to utilize our excess liquidity. Total deposits were $5.56 billion at March 31, 2026, a decrease of $31.1 million from December 31, 2025.

March 31, 2026

Securities

As of

Percent Change From

March 31, 

December 31, 

March 31, 

December 31, 

March 31, 

  ​ ​ ​

2026

  ​ ​ ​

2025

  ​ ​ ​

2025

  ​ ​ ​

2025

  ​ ​ ​

2025

Securities available-for-sale, at fair value

U.S. Treasuries

$

164,986

$

165,860

$

160,191

(0.5)

3.0

U.S. government agencies

68,625

29,176

38,047

135.2

80.4

U.S. government agencies mortgage-backed

85,210

88,780

98,929

(4.0)

(13.9)

States and political subdivisions

203,344

206,375

209,117

(1.5)

(2.8)

Collateralized mortgage obligations

363,331

359,305

390,891

1.1

(7.1)

Asset-backed securities

44,505

45,816

49,701

(2.9)

(10.5)

Collateralized loan obligations

184,711

194,464

199,845

(5.0)

(7.6)

Equity securities

731

747

-

(2.1)

N/M

Total securities

$

1,115,443

$

1,090,523

$

1,146,721

2.3

(2.7)

N/M – Not meaningful.

Securities available-for-sale increased $24.9 million as of March 31, 2026, compared to December 31, 2025, but decreased $31.3 million compared to March 31, 2025. The increase in the portfolio during 2026 was driven by $106.9 million in purchases, partially offset by paydowns totaling $62.0 million along with maturities and calls totaling $16.2 million and a $3.3 million increase in unrealized losses on securities available-for-sale. We continue to position the portfolio in higher credit quality, shorter duration securities with an appropriate mix of fixed- and floating-rate exposures.

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Table of Contents

March 31, 2026

Loans

As of

Percent Change From

March 31, 

December 31, 

March 31, 

December 31, 

March 31, 

2026

2025

2025

2025

  ​ ​ ​

2025

Commercial

$

845,278

$

842,130

$

732,874

0.4

15.3

Leases

539,116

548,256

505,455

(1.7)

6.7

Commercial real estate – investor

1,169,318

1,212,384

1,105,440

(3.6)

5.8

Commercial real estate – owner occupied

702,986

706,567

669,964

(0.5)

4.9

Construction

143,563

173,630

205,839

(17.3)

(30.3)

Residential real estate – investor

69,763

70,225

50,103

(0.7)

39.2

Residential real estate – owner occupied

239,711

230,432

210,239

4.0

14.0

Multifamily

357,131

339,131

341,253

5.3

4.7

HELOC

235,637

235,293

104,575

0.1

125.3

Powersport

674,116

696,959

-

(3.3)

N/M

Other 1

208,618

197,124

14,490

5.8

N/M

Total loans

$

5,185,237

$

5,252,131

$

3,940,232

(1.3)

31.6

N/M – Not meaningful.

1 The “Other” classification includes consumer loans, such as collector cars, manufactured homes, and solar loans, as well as overdrafts.

Total loans were $5.19 billion as of March 31, 2026, a decrease of $66.9 million from December 31, 2025. The decrease in total loans in the first three months of 2026, compared to December 31, 2025, was primarily due to paydowns, net of originations, in commercial real estate – investor, construction, and powersport. Total loans increased $1.25 billion compared to March 31, 2025, which was primarily due to the $1.20 billion portfolio acquired from Bancorp Financial. Excluding the acquisition, the Bank achieved organic loan growth, net of paydowns, of $49.3 million, comprised of commercial, leases, residential real estate – owner occupied, and other, partially offset by net decreases in commercial real estate - investor, construction, and multifamily. As required by CECL, the balance (or amortized cost basis) of purchased credit deteriorated loans, or PCD loans (discussed below) is carried on a gross basis, rather than net of the associated credit loss estimate, and the expected credit losses for PCD loans are estimated and separately recognized as part of the allowance for credit losses, or ACL.

The addition of the powersports loan portfolio has given us a more balanced loan portfolio by broadening the scope of our consumer lending and offering a higher yield in a lower rate environment. During the three months ended March 31, 2026, we originated $79.1 million powersport loans with a weighted average yield of 10.67%. As of March 31, 2026, the weighted average FICO score, at the time of origination, of the entire powersport portfolio is 727.

Weighted

March 31, 

Average

2026

FICO

Tier 1

$

351,101

776

Tier 2

131,894

710

Tier 3

80,937

683

Tier 4

40,382

657

Tier 5

69,802

606

Total Powersport

$

674,116

727

The following table sets forth the total of powersport by collateral type:

March 31, 

% of

2026

Total

New

$

517,948

76.8

%

Used

156,168

23.2

Total Powersport

$

674,116

100.0

%

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Table of Contents

The quality of our loan portfolio is impacted not only by our credit decisions but also by the economic health of the communities in which we operate. Since we are located in a corridor with significant open space and undeveloped real estate, real estate lending (including commercial real estate, construction, residential, multifamily, and HELOCs) has been and continues to be a sizeable portion of our portfolio. These categories comprised 56.3% of the portfolio as of March 31, 2026, compared to 56.5% of the portfolio as of December 31, 2025. At March 31, 2026, our outstanding commercial real estate loans and undrawn commercial real estate commitments, excluding owner occupied real estate, were equal to 203.7% of our Tier 1 capital plus allowance for credit losses, a decrease from 220.3% at December 31, 2025. We continue to oversee and seek to manage our loan portfolio in accordance with interagency guidance on risk management.

Asset Quality

Nonperforming loans consist of nonaccrual loans and loans 90 days or greater past due. Nonperforming loans increased by $22.7 million to $75.5 million at March 31, 2026, from $52.8 million at December 31, 2025, and increased by $40.7 million from $34.8 million at March 31, 2025. The increase in total nonperforming loans as of March 31, 2026 is driven by non-accrual additions of a few larger commercial relationships and two larger relationships that are 90 days past due and accruing. The two past due and accruing relationships, one in commercial real estate – owner occupied and another in commercial real estate – investor, are in the process of being renewed, and both relationships are well positioned from a collateral perspective. Purchased credit deteriorated loans, or PCD loans, are purchased loans that, as of the date of acquisition, we determined had experienced a more-than-insignificant deterioration in credit quality since origination. PCD loans are included in our nonperforming loan disclosures, if such loans otherwise meet the definition of a nonperforming loan. Management continues to carefully monitor loans considered to be in a classified status. Nonperforming loans as a percent of total loans were 1.5% as of March 31, 2026, 1.0% as of December 31, 2025, and 0.9% as of March 31, 2025. The distribution of our nonperforming loans is shown in the following table.

March 31, 2026

Nonperforming Loans

As of

Percent Change From

March 31, 

December 31, 

March 31, 

December 31, 

March 31, 

2026

2025

2025

2025

2025

Commercial

$

22,527

$

9,761

$

12,475

130.8

80.6

Leases

2,952

2,899

848

1.8

248.1

Commercial real estate – investor

16,423

11,377

1,968

44.4

734.5

Commercial real estate – owner occupied

22,268

19,743

11,297

12.8

97.1

Construction

2,086

737

4,989

183.0

(58.2)

Residential real estate – investor

669

681

769

(1.8)

(13.0)

Residential real estate – owner occupied

1,916

1,852

1,563

3.5

22.6

Multifamily

1,489

1,494

332

(0.3)

348.5

HELOC

1,603

1,222

545

31.2

194.1

Powersport

2,394

2,778

-

(13.8)

N/M

Other 1

1,177

287

5

310.1

N/M

Total nonperforming loans

$

75,504

$

52,831

$

34,791

42.9

117.0

N/M – Not meaningful.

1 The “Other” classification includes consumer loans, such as collector cars, manufactured homes, and solar loans, as well as overdrafts.

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Table of Contents

The components of our nonperforming assets are shown in the following table:

March 31, 2026

Nonperforming Assets

As of

Percent Change From

March 31, 

December 31, 

March 31, 

December 31, 

March 31, 

  ​

2026

  ​

2025

  ​

2025

  ​

2025

2025

Nonaccrual loans

$

62,636

$

47,952

$

33,394

30.6

87.6

Loans past due 90 days or more and still accruing interest

 

12,868

 

4,879

 

1,397

163.7

821.1

Total nonperforming loans

 

75,504

 

52,831

 

34,791

42.9

117.0

Other real estate owned

 

632

 

1,427

 

2,878

(55.7)

(78.0)

Repossessed assets 1

 

858

 

1,363

 

484

(37.1)

77.3

Total nonperforming assets

$

76,994

$

55,621

$

38,153

38.4

101.8

30-89 days past due loans and still accruing interest

$

50,036

$

52,169

$

21,951

Nonaccrual loans to total loans

1.2

%

0.9

%

0.8

%

Nonperforming loans to total loans

1.5

%

1.0

%

0.9

%

Nonperforming assets to total loans plus OREO and repossessed assets

1.5

%

1.1

%

1.0

%

Allowance for credit losses

$

72,126

$

72,301

$

41,551

Allowance for credit losses to total loans

1.4

%

1.4

%

1.1

%

Allowance for credit losses to nonaccrual loans

115.2

%

150.8

%

124.4

%

1 Repossessed assets are reported within other assets.

Loan charge-offs, net of recoveries, for the first quarter of 2026 as compared to the prior linked quarter and year over year quarter are shown in the following table:

Loan Charge–offs, Net of Recoveries

Three Months Ended

March 31, 

% of

December 31, 

% of

March 31, 

% of

2026

Total1

2025

Total1

2025

Total1

Commercial

$

1,298

13.3

$

(44)

(0.7)

$

3,414

78.4

Leases

197

2.0

15

0.2

93

2.1

Commercial real estate – investor

3,919

40.1

(14)

(0.2)

(14)

(0.3)

Commercial real estate – owner occupied

(5)

(0.1)

1,125

18.8

39

0.9

Construction

-

-

-

-

821

18.9

Residential real estate – investor

(2)

-

(1)

-

(2)

-

Residential real estate – owner occupied

(7)

(0.1)

(11)

(0.2)

(30)

(0.7)

Multifamily

-

-

-

-

-

-

HELOC

(6)

(0.1)

(49)

(0.8)

(12)

(0.3)

Powersport

3,894

39.9

4,466

74.7

-

-

Other 2

488

5.0

494

8.2

44

1.0

Net charge–offs (recoveries)

$

9,776

100.0

$

5,981

100.0

$

4,353

100.0

1 Represents the percentage of net charge-offs attributable to each category of loans.

2 The “Other” classification includes consumer loans, such as collector cars, manufactured homes, and solar loans, as well as overdrafts.

Net charge offs, reported in the above table, reflect continuing management attention to credit quality and remediation efforts. The increase in gross charge-offs for the first quarter of 2026, as compared to the prior quarters presented, were primarily due to powersport loans of $4.7 million, one commercial real estate charge-off for $3.9 million, and a $1.3 million charge-off on a commercial relationship. Powersport loans are measured for asset quality at origination based on FICO scores, then based on past due status through the life of the loan, and charge-off occurs once a loan is past due 120 days. We have continued our conservative loan valuations and aggressive recovery efforts on prior charge-offs.

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Table of Contents

Classified loans include nonaccrual loans, accruing substandard, and doubtful loans. Classified assets include classified loans, OREO, and repossessed assets. Loans classified as substandard are inadequately protected by either the current net worth and ability to meet payment obligations of the obligor, or by the collateral pledged to secure the loan, if any. These loans have a well-defined weakness or weaknesses that jeopardize the liquidation of the debt and carry the distinct possibility that we will sustain some loss if the deficiencies remain uncorrected. Loans classified as doubtful have all the weaknesses inherent as those classified substandard with the added characteristic that the weaknesses make collection or liquidation in full, on the basis of currently existing facts, conditions and values, highly questionable and improbable.

The following table shows classified assets by classification for the following periods:

March 31, 2026

Classified Assets

As of

Percent Change From

March 31, 

December 31, 

March 31, 

December 31, 

March 31, 

2026

2025

2025

2025

2025

Commercial

$

50,640

$

51,587

$

20,807

(1.8)

143.4

Leases

2,604

2,428

848

7.2

207.1

Commercial real estate – investor

14,959

14,245

14,299

5.0

4.6

Commercial real estate – owner occupied

60,594

64,081

26,818

(5.4)

125.9

Construction

12,983

11,421

18,201

13.7

(28.7)

Residential real estate – investor

1,012

1,142

1,283

(11.4)

(21.1)

Residential real estate – owner occupied

1,886

1,897

1,759

(0.6)

7.2

Multifamily

1,489

1,494

332

(0.3)

348.5

HELOC

1,832

1,466

686

25.0

167.1

Powersport

204

68

-

200.0

N/M

Other

369

270

10

36.7

N/M

Total classified loans

148,572

150,099

85,043

(1.0)

74.7

Other real estate owned

632

1,427

2,878

(55.7)

(78.0)

Repossessed assets 1

858

1,363

484

(37.1)

77.3

Total classified assets

$

150,062

$

152,889

$

88,405

(1.8)

69.7

N/M - Not meaningful

1 Repossessed assets are reported within other assets.

Total classified loans decreased $1.5 million as of March 31, 2026, from December 31, 2025, but increased $63.5 million compared to March 31, 2025. The decrease in classified loans since December 31, 2025, is due to outflows to classified loans of $10.2 million, offset by additions of $8.7 million. Outflows consisted of $6.0 million of loans paid off, $1.6 million of classified loans upgraded, $1.1 million of principal reductions through payments and partial charge offs, $1.3 million of loans charged off, and $235,000 of loans transferred into OREO. Classified assets decreased as of March 31, 2026, compared to the prior linked quarter end, due to the decreases to classified loans and a total decrease of $1.3 million related to OREO and repossessed assets. The $61.7 million increase in classified assets as of March 31, 2026, compared to March 31, 2025, is primarily due to the classified loan increase of $63.5 million, noted above, less a reduction in OREO balances year over year. Classified loans since March 31, 2025 had additions of $149.3 million and were offset by outflows of $85.8 million which consisted of $54.8 million of loans paid off, $16.7 million of classified loans upgraded, $2.4 million of loans charged off, $5.7 million of net principal reductions and partial charge offs, $5.2 million transferred to OREO, and $1.0 million repossessed. Management monitors a ratio of classified assets to the sum of Bank Tier 1 capital and the ACL on loans as another measure of overall change in loan related asset quality, which is referred to as the “classified assets ratio.” The classified assets ratio was 16.93% for the period ended March 31, 2026, compared to 17.82% as of December 31, 2025, and 13.12% as of March 31, 2025.

Allowance for Credit Losses on Loans

The provision for credit losses, which includes a provision for losses on unfunded commitments, is a charge to earnings to maintain the allowance for credit losses (“ACL”) at a level consistent with management’s assessment of expected losses in the loan portfolio at the balance sheet date.

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At March 31, 2026, our ACL on loans totaled $72.1 million, and our ACL on unfunded commitments, included in other liabilities, totaled $2.0 million. In the first quarter of 2026, we recorded a provision expense on loans of $9.6 million driven by increased charge-offs and the downgrade of one commercial relationship. Further, we recorded a $101,000 provision release on unfunded commitments, primarily due to an adjustment of historical benchmark assumptions, such as funding rates and the period used to forecast those rates, within the ACL calculation. These adjustments resulted in a $9.5 million net expense to the provision for credit losses for the first quarter of 2026.

Management estimates the amount of provision required on a quarterly basis and records the appropriate provision expense, or release of expense, to maintain an adequate reserve for all potential and estimated credit losses on loans, leases and unfunded commitments. The ACL on loans totaled $72.1 million as of March 31, 2026, $72.3 million as of December 31, 2025, and $41.6 million as of March 31, 2025. Our ACL on loans to total loans was 1.4% as of March 31, 2026 and December 31, 2025, and 1.1% March 31, 2025. See Item 7 – Critical Accounting Estimates in the Management Discussion and Analysis in our 2025 Annual Report in Form 10-K for discussion of our ACL methodology on loans. Allocations of the ACL may be made for specific loans, but the entire allowance is available for any loan that, in our judgment, should be charged-off.

Below is a reconciliation of the activity in the allowance for credit losses on loans for the periods indicated:

Three Months Ended

March 31, 

December 31, 

March 31, 

2026

2025

2025

Allowance at beginning of period

$

72,301

$

75,037

$

43,619

Charge–offs:

Commercial

1,328

28

3,446

Leases

312

15

107

Commercial real estate – investor

3,933

-

-

Commercial real estate – owner occupied

-

1,126

47

Construction

-

-

821

Residential real estate – investor

-

-

-

Residential real estate – owner occupied

-

-

-

Multifamily

-

-

-

HELOC

2

-

-

Powersport

4,661

5,136

-

Other 1

557

551

108

Total charge–offs

10,793

6,856

4,529

Recoveries:

Commercial

30

72

32

Leases

115

-

14

Commercial real estate – investor

14

14

14

Commercial real estate – owner occupied

5

1

8

Construction

-

-

-

Residential real estate – investor

2

1

2

Residential real estate – owner occupied

7

11

30

Multifamily

-

-

-

HELOC

8

49

12

Powersport

767

670

-

Other 1

69

57

64

Total recoveries

1,017

875

176

Net charge-offs

9,776

5,981

4,353

Provision for credit losses on loans 2

9,601

3,245

2,285

Allowance at end of period

$

72,126

$

72,301

$

41,551

Average total loans (exclusive of loans held–for–sale)

$

5,205,721

$

5,275,389

$

3,957,730

Net charge–offs to average loans

0.76

%

0.45

%

0.45

%

1 The “Other” classification includes consumer loans, such as collector cars, manufactured homes, and solar loans, as well as overdrafts.

2 Amount does not include the provision for unfunded commitment liability.

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The coverage ratio of the ACL on loans to nonperforming loans was 95.5% as of March 31, 2026, which was a decrease from the coverage ratio of 136.9% as of December 31, 2025, and a decrease from 119.4% as of March 31, 2025. Excluding loans past due 90 days and accruing that are in the process of renewal, the coverage ratio for March 31, 2026 was 115.5%. Net charge-offs to average loans increased in the current quarter, though remaining manageable, at 0.76% for the quarter ended March 31, 2026, compared to 0.45% for the quarters ended December 31, 2025 and March 31, 2025.

In management’s judgment, an adequate ACL has been established to encompass the current lifetime expected credit losses at March 31, 2026, as well as general changes in lending policy, procedures and staffing, and other external factors. However, there can be no assurance that actual losses will not exceed the estimated amounts in the future, based on unforeseen economic events, changes in business climates and the condition of collateral at the time of default and repossession. Continued volatility in the economic environment stemming from the impacts of and response to inflation, tariffs, potential recession, and the war in Ukraine and the war in Iran, and the associated effects on our customers, or other factors, such as changes in business climates and the condition of collateral at the time of default or repossession, may revise our current expectations of future credit losses in future reporting periods.

Other Real Estate Owned

As of March 31, 2026, OREO totaled $632,000, reflecting a decrease of $795,000 from $1.4 million at December 31, 2025, and a decrease of $2.2 million from $2.9 million at March 31, 2025. In the first quarter of 2026, there was one OREO sale totaling $1.4 million, net of gains, and one property transferred with a value of $632,000. The valuation adjustment balance was reversed along with the related OREO balance due to the sale in the first quarter of 2026. There was no valuation adjustment in the fourth quarter of 2025 and we recorded a valuation  adjustment of $454,000 in the first quarter of 2025.

March 31, 2026

OREO

Three Months Ended

Percent Change From

March 31, 

December 31, 

March 31, 

December 31, 

March 31, 

2026

2025

2025

2025

2025

Balance at beginning of period

$

1,427

$

6,416

$

21,617

(77.8)

(93.4)

Property additions, net of transfer adjustments

632

-

-

N/M

N/M

Less:

Proceeds from property disposals, net of participation purchase and of gains/losses

1,427

4,989

18,285

(71.4)

(92.2)

Period valuation adjustments

-

-

454

-

(100.0)

Balance at end of period

$

632

$

1,427

$

2,878

(55.7)

(78.0)

N/M – Not meaningful.

In management’s judgment, the property valuation allowance as established presents OREO at current estimates of fair value less estimated costs to sell; however, there can be no assurance that additional losses will not be incurred on disposals or upon updates to valuations in the future. These valuations are reversed when the property is sold.

OREO Properties by Type

March 31, 2026

December 31, 2025

March 31, 2025

Amount

% of Total

Amount

% of Total

Amount

% of Total

 Single family residence 

$

632

100

$

-

-

$

-

-

 Commercial property 

-

-

1,427

100

2,695

94

 Vacant land 

-

-

-

-

183

6

Total other real estate owned

$

632

100

$

1,427

100

$

2,878

100

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Deposits and Borrowings

March 31, 2026

Deposits

As of

Percent Change From

March 31, 

December 31, 

March 31, 

December 31, 

March 31, 

2026

2025

2025

2025

  ​ ​ ​

2025

Noninterest bearing demand

$

1,755,548

$

1,739,117

$

1,713,711

0.9

2.4

Savings

1,117,316

1,121,888

952,602

(0.4)

17.3

NOW accounts

701,712

693,573

652,444

1.2

7.6

Money market accounts

976,010

930,079

829,533

4.9

17.7

Certificates of deposit of less than $100,000

440,553

489,879

334,694

(10.1)

31.6

Certificates of deposit of $100,000 through $250,000

376,868

412,655

252,276

(8.7)

49.4

Certificates of deposit of more than $250,000

196,992

208,878

117,531

(5.7)

67.6

Total deposits

$

5,564,999

$

5,596,069

$

4,852,791

(0.6)

14.7

Total deposits were $5.56 billion at March 31, 2026, which reflects a $31.1 million decrease from total deposits of $5.60 billion at December 31, 2025, but an increase of $712.2 million from total deposits of $4.85 billion at March 31, 2025. The decrease in deposits at March 31, 2026, compared to December 31, 2025, was primarily due to decreases in savings accounts of $4.6 million and time deposits of $97.0 million, primarily due to the roll off of higher rate brokered deposits and other exception-priced time deposits acquired from the Bancorp Financial acquisition. These decreases were partially offset by increases in noninterest bearing deposits of $16.4 million, NOW accounts of $8.1 million and money market accounts of $46.0 million. The increase in deposits at March 31, 2026, compared to March 31, 2025, stemmed primarily from the acquisition of Bancorp Financial, which impacted all deposit types. Total quarterly average deposits increased $764.8 million, or 15.9%, in the year over year period, primarily driven by the acquisition of Bancorp Financial, which included an increase in average time deposits of $337.3 million, savings accounts of $178.1 million,  money market accounts of $144.9 million, NOW accounts of $69.4 million, and noninterest bearing deposits of $35.1 million. Included in our quarterly average time deposits are $46.6 million of brokered deposits compared to none at March 31, 2025. Brokered deposits totaling $115.0 million were assumed in the acquisition of Bancorp Financial and we expect these deposits to run-off by early 2028.

The following table presents estimated insured and uninsured deposits at March 31, 2026, and December 31, 2025, by deposit type, as well as the weighted average rates for each year to date ending period.

March 31, 2026

December 31, 2025

Total Deposits

Insured Deposits

Uninsured Deposits

Average Rate Paid

Total Deposits

Insured Deposits

Uninsured Deposits

Average Rate Paid

Noninterest bearing demand   

$

1,755,548

$

1,165,286

$

590,262

-

%

$

1,739,117

$

1,141,542

$

597,575

-

%

Savings

1,117,316

1,022,199

95,117

0.79

1,121,888

1,025,941

95,947

0.73

NOW accounts

701,712

508,484

193,228

0.48

693,573

495,397

198,176

0.45

Money market accounts

976,010

558,441

417,569

1.78

930,079

548,289

381,790

1.90

Time deposits

1,014,413

849,896

164,517

2.75

1,111,412

937,045

174,367

2.92

Total

$

5,564,999

$

4,104,306

$

1,460,693

1.05

%

$

5,596,069

$

4,148,214

$

1,447,855

1.06

%

Collateralized public funds

$

220,165

$

15,602

$

204,563

$

219,939

$

15,832

$

204,107

Deposits balances were stable during the first quarter of 2026, reflecting a nominal decrease of 0.6% for the three months ended March 31, 2026, compared to December 31, 2025. Changes in the rate paid on time deposits reflect a gradual repricing of accounts opened during a higher interest rate environment. The aggregate rate paid on deposits and the overall product mix were largely unchanged during the quarter.

In addition to deposits, we used other liquidity sources for our funding needs in all periods presented, such as repurchase agreements and other short-term borrowings with the FHLBC. Our borrowings at the FHLBC require the Bank to be a member and invest in the stock of the FHLBC, and total borrowings are generally limited to the lower of 35% of total assets or the book value of eligible pledged assets after application of FHLBC margins and collateral valuation adjustments. Securities sold under repurchase agreements totaled $23.1 million at March 31, 2026, a $639,000, or 2.7% decrease from $23.8 million at December 31, 2025, and a decrease of $15.5 million, or 40.2%, from March 31, 2025. There were outstanding short-term FHLBC borrowings of $200.0 million as of March 31, 2026, compared to $215.0 million as of December 31, 2025, and no short-term FHLBC borrowings outstanding as of March 31, 2025.

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We are also indebted on $25.8 million of junior subordinated debentures, net of deferred issuance costs, as of March 31, 2026, which are related to the trust preferred securities issued by its statutory trust subsidiary, Old Second Capital Trust II (“Trust II”). The Trust II issuance converted from fixed to floating rate at three month LIBOR, which is now three month Term SOFR, plus 150 basis points beginning June 15, 2017. Upon conversion to a floating rate, we initiated a cash flow hedge which resulted in net year to date interest rate paid on this debt of 4.66% as of March 31, 2026, as compared to 6.77%, which was the rate paid during the period prior to the June 15, 2017, rate reset.

In the second quarter of 2021, we entered into Subordinated Note Purchase Agreements with certain qualified institutional buyers pursuant to which we issued $60.0 million in aggregate principal amount of our 3.50% Fixed-to-Floating Rate Subordinated Notes due April 15, 2031 (the “Notes”). We sold the Notes to eligible purchasers in a private offering, and the proceeds of this issuance were used for general corporate purposes. The Notes bear interest at a fixed annual rate of 3.50% through April 14, 2026, payable semi-annually in arrears. As of April 15, 2026, forward, the interest rate on the Notes will generally reset quarterly to a rate equal to three-month Term SOFR (as defined by the Note) plus 273 basis points, payable quarterly in arrears. The Notes have a stated maturity of April 15, 2031, and are redeemable, in whole or in part, on April 15, 2026, or any interest payment date thereafter, and at any time upon the occurrence of certain events. As of March 31, 2026, we had $59.6 million of subordinated debentures outstanding, net of deferred issuance costs. On April 15, 2026, we redeemed $30.0 million aggregate principal amount of the Notes. See Note 1 – Subsequent Events for additional information.

Capital

As of March 31, 2026, total stockholders’ equity was $893.3 million, which was a decrease of $3.5 million from $896.8 million as of December 31, 2025. This decrease was primarily attributable to a $20.0 million increase in treasury stock. During the first three months of 2026, we repurchased 1,175,859 shares for $23.1 million under our stock repurchase program and withheld 67,357 shares with a value of $1.4 million to satisfy tax withholding obligations related to restricted stock unit vestings. The increase in treasury stock was partially offset by the issuance of 152,021 shares related to restricted stock unit vestings, with a value of $2.7 million, and 87,631 shares related to performance-based restricted stock unit vestings, with a value of $1.7 million. Total stockholders’ equity also decreased due to $3.7 million of dividends paid to common stockholders and an increase of $2.4 million in unrealized net losses on available-for-sale securities and swaps, recorded within accumulated other comprehensive loss, driven by changes in market interest rates during the quarter. These decreases were partially offset by net income of $25.6 million for the period. Total stockholders’ equity as of March 31, 2026, increased $198.8 million compared to March 31, 2025, primarily due to the Bancorp Financial acquisition and net income year over year.

The following table shows the regulatory capital ratios and the current well capitalized regulatory requirements for the Company and the Bank as of the dates indicated:

Minimum Capital

Well Capitalized

Adequacy with

Under Prompt

Capital Conservation

Corrective Action

March 31, 

December 31, 

March 31, 

Buffer, if applicable1

Provisions2

2026

2025

2025

The Company

Common equity tier 1 capital ratio

7.00

%

N/A

13.13

%

12.99

%

13.47

%

Total risk-based capital ratio

10.50

N/A

15.64

15.46

16.24

Tier 1 risk-based capital ratio

8.50

N/A

13.55

13.41

14.01

Tier 1 leverage ratio

4.00

N/A

11.88

11.70

11.58

The Bank

Common equity tier 1 capital ratio

7.00

%

6.50

%

13.80

%

13.17

%

13.64

%

Total risk-based capital ratio

10.50

10.00

14.88

14.22

14.58

Tier 1 risk-based capital ratio

8.50

8.00

13.80

13.17

13.64

Tier 1 leverage ratio

4.00

5.00

12.09

11.49

11.27

1 Amounts are shown inclusive of a capital conservation buffer of 2.50%.

2 The prompt corrective action provisions are only applicable at the Bank level.

N/A - Not applicable

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As of March 31, 2026, the Bank exceeded the minimum capital ratios to be deemed “well capitalized” and met the capital conservation buffer requirements. In addition to the above regulatory ratios, our GAAP common equity to total assets ratio, which is used as a performance measure for capital analysis and peer comparisons, increased from 12.99% at December 31, 2025, to 13.04% at March 31, 2026. Our GAAP tangible common equity to tangible assets ratio was 11.07% at March 31, 2026, compared to 11.02% as of December 31, 2025. The decrease in tangible common equity from December 31, 2025, to March 31, 2026, was primarily due to a $20.0 million increase in treasury stock and a $2.4 million increase in unrealized losses recorded in accumulated other comprehensive loss.

Liquidity

Liquidity is our ability to fund operations, to meet depositor withdrawals, to provide for customers’ credit needs, and to meet maturing obligations and existing commitments. Our liquidity principally depends on our cash flows from operating activities, investment in and maturity of assets, changes in balances of deposits and borrowings, and our ability to borrow funds. Through the first quarter of 2026, we experienced a decrease in both loans and deposits. We managed the change in our funding through a decrease in average borrowings from the FHLBC through March 31, 2026, compared to the prior year end. We seek to ensure our funding needs are met by maintaining a level of liquidity through asset and liability management. We monitor our borrowing capacity at the FHLBC as part of our liquidity management process as supervised by our Asset and Liability Committee (“ALCO”) and reviewed by our Board of Directors. In addition, our senior management team monitors cash balances daily to ensure we have adequate liquidity to meet our operational and financing needs. As of March 31, 2026, our cash on hand liquidity totaled $115.7 million, a decrease of $8.3 million over cash balances held as of December 31, 2025.

Net cash inflows from operating activities were $36.9 million during the first three months of 2026, compared with net cash inflows of $17.8 million in the same period of 2025.  Funds used to originate loans held-for-sale, net of proceeds from sales of loans held-for-sale, resulted in outflows for both the first three months of 2026 as well as the like period of 2025. Interest paid, net of interest received, combined with changes in other assets and liabilities were a source of outflows for the three months ended March 31, 2026 and 2025. The management of investing and financing activities, as well as market conditions, determines the level and the stability of net interest cash flows. Management’s policy is to mitigate the impact of changes in market interest rates to the extent possible, as part of the balance sheet management process.

Net cash inflows from investing activities were $29.6 million in the three months ended March 31, 2026, compared to net cash inflows of $76.7 million in the same period in 2025. In the first three months of 2026, securities transactions accounted for net outflows of $28.7 million, and the principal change on loans accounted for net inflows of $56.8 million. In the first three months of 2025, securities transactions accounted for net inflows of $23.5 million, and principal on loans funded, net of paydowns, accounted for net inflows of $36.8 million.

Net cash outflows from financing activities in the three months ended March 31, 2026, were $74.8 million, compared with net cash inflows of $62.2 million in the three months ended March 31, 2025. Net deposit outflows in the first three months of 2026 were $31.0 million compared to net deposit inflows of $84.3 million in the first three months of 2025. Other short-term borrowings had $15.0 million of net cash outflows in the first three months of 2026, compared to net cash outflows of $20.0 million for other short-term borrowings in the first three months of 2025. Changes in securities sold under repurchase agreements accounted for outflows of $639,000 and inflows of $2.0 million for the three months ended March 31, 2026 and 2025, respectively. Dividends paid on our common stock totaled $3.7 million for the three months ended March 31, 2026, and $2.7 million for the three months ended March 31, 2025. The purchase of treasury stock in the first three months of 2026 due to shares acquired with equity award vestings as well as share repurchases resulted in outflows of $24.5 million, compared to cash outflows of $1.4 million in the first three months of 2025 related to shares acquired from equity award vestings.

Cash and cash equivalents for the three months ended March 31, 2026 totaled $115.7 million, as compared to $124.0 million as of December 31, 2025, and $256.1 million as of March 31, 2025. The decrease in cash and cash equivalents for the three months ended March 31, 2026, as compared to the prior year end, was primarily attributable to the increase in treasury stock due to share repurchases, the increase in securities available-for-sale based on strategic purchases, and the decrease in customer deposits. In addition to cash and cash equivalents on hand or held as deposits with other financial institutions, we rely on funding sources from customer deposits, cash flows from securities available-for-sale and loans, and a line of credit with the FHLBC to meet potential liquidity needs. These sources of liquidity are immediately available to satisfy any funding requirements due to depositor or borrower demands through the ordinary course of our business. Additional sources of funding available include a $30.0 million undrawn line of credit held by the Company with a third party financial institution, as well as unpledged securities available-for-sale.

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Item 3. Quantitative and Qualitative Disclosures about Market Risk

Interest Rate Risk

We are subject to interest rate risk from changes in interest rates on assets (loans and securities), liabilities (customer deposits and borrowed funds), and off-balance sheet derivative instruments (interest rate swaps). Fluctuations in interest rates may have a material impact on the fair market values of our financial instruments, cash flows, and net interest income. Like most financial institutions, we are exposed to changes in both short-term and long-term interest rates. We believe that a financial institution’s ability to effectively manage its interest rate risk profile and strategically position its balance sheet through interest rate cycles is critical to sustaining financial performance.

The Federal Reserve Board (“FRB”) held the federal funds target rate at a range of 3.50% to 3.75% during the first quarter of 2026, consistent with market expectations. Economic conditions remained relatively stable, and the forward curve currently does not reflect expectations for interest rate cuts in 2026.

We manage interest rate risk within guidelines established by our asset-liability policy, which are designed to limit the level of interest rate exposure. In practice, we seek to manage interest rate risk so that potential exposure does not pose a material risk to future earnings. We are exposed to various market risks in the normal course of business, including credit risk, liquidity risk, and interest rate risk. Other forms of market risk, such as foreign currency exchange risk and commodity price risk, do not arise in the normal course of our operations. In addition, because we do not maintain a trading portfolio, we are not exposed to significant market risk from trading activities. Our interest rate risk exposures at March 31, 2026, and December 31, 2025, are summarized in the table below.

Our net income may be influenced by a number of external factors. These factors include overall economic conditions and actions taken by regulatory authorities. Net income may also be affected by the amounts of and rates at which assets and liabilities reprice, differences between assumed and actual prepayment speeds on loans and securities, and early withdrawal of deposits. Additional factors include the exercise of call options on borrowings or securities, competitive pressures, changes in the level or slope of the yield curve, and changes in historical relationships between interest rate indices, such as SOFR and Prime. Balance sheet growth or contraction may also impact net income.

Our Asset‑Liability Committee (“ALCO”) manages interest rate risk across a range of interest rate environments by structuring our on- and off‑balance sheet positions, including the use of interest rate swap derivatives, as discussed in Note 19 to the consolidated financial statements in our Annual Report on Form 10‑K for the year ended December 31, 2025. The ALCO reviews asset‑liability modeling and interest rate risk analyses and reports its findings to the Board of Directors no less than quarterly, including assessments of interest rate risk exposure and the potential impact on earnings and equity. As of the reporting date, the balance sheet exhibited a moderately asset‑sensitive profile, as variable‑rate assets generally reprice more quickly than our longer‑duration, lower‑beta deposit base. Following liquidity events in the banking industry during 2023, the ALCO evaluated our liquidity profile and concluded that the Bank maintains a strong liquidity position. As a prudent measure, internal reporting was enhanced to further segment deposits by insured, uninsured, and collateralized categories, and to more closely track funding sources and uses.

We also maintain a Risk Committee that is chaired by our Chief Risk Officer. The committee reports no less than quarterly to senior management and the Board of Directors on compliance with established risk tolerance limits and on changes in key risk factors arising from portfolio activity and market conditions. Our enterprise risk management framework is governed by this committee, with input from line‑of‑business leaders, senior management, and the Board.

We utilize simulation analysis to quantify the potential impact of various interest rate scenarios on net interest income. The simulation model incorporates expected cash flows, repricing characteristics, and embedded options of our assets and liabilities. Earnings at risk are calculated by comparing net interest income under a stable interest rate scenario to net interest income under alternative rate scenarios. As of March 31, 2026, our net interest income profile remained positioned to benefit from rising interest rates, both in dollar terms and as a percentage change. Compared to December 31, 2025, the profile reflects slightly increased sensitivity to rising rates, primarily due to growth in cash balances resulting from earnings and principal repayments, including amortization, maturities, calls, and prepayments.

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Table of Contents

The following table summarizes the effect on annual income before income taxes based upon an immediate increase or decrease in interest rates of 0.5%, 1.0%, and 2.0%, with no change in the slope of the yield curve:

Analysis of Net Interest Income Sensitivity

Immediate Changes in Rates

(Dollars in thousands)

  ​ ​ ​

(2.0)

%

  ​ ​ ​

(1.0)

%

  ​ ​ ​

  ​

(0.5)

%

  ​ ​ ​

  ​

0.5

%

  ​ ​ ​

  ​

1.0

%

  ​ ​ ​

  ​

2.0

%

March 31, 2026

Dollar change

$

(35,998)

$

(17,947)

$

(8,366)

$

8,937

$

17,987

$

32,400

Percent change

(10.4)

%

(5.2)

%

(2.4)

%

2.6

%

5.2

%

9.4

%

December 31, 2025

Dollar change

$

(35,505)

$

(18,190)

$

(9,026)

$

8,817

$

17,732

$

31,490

Percent change

(10.6)

%

(5.4)

%

(2.7)

%

2.6

%

5.3

%

9.4

%

The amounts and assumptions used in the simulation model are not intended to be indicative of actual future results. Actual results may differ materially from simulated outcomes due to differences in the timing, frequency, and magnitude of interest rate changes, changes in balance sheet composition, evolving market conditions, and management actions taken in response to those conditions. In addition, the simulated results do not reflect the impact of any potential management actions that could be implemented to mitigate interest rate risk.

Effects of Inflation

In management’s opinion, changes in interest rates affect our financial condition to a greater extent than changes in inflation, however we monitor both. The annual U.S. inflation rate increased to 3.3% in March 2026, compared to 2.7% in the prior quarter; while core CPI increased modestly to 2.6%. Recent inflation trends have been influenced by volatility in energy prices and broader geopolitical developments. Elevated inflation could place upward pressure on operating expenses and may impact the financial condition of certain borrowers. Inflation at currently observed levels has had a minimal impact on our financial results.

Item 4. Controls and Procedures

Evaluation of Disclosure Controls and Procedures

The Chief Executive Officer and Chief Financial Officer have evaluated the effectiveness of the design and operation of the Company’s disclosure controls and procedures, as defined in Rule 13a-15(e) promulgated under the Securities and Exchange Act of 1934, as amended, as of March 31, 2026. Based on that evaluation, the Chief Executive Officer and Chief Financial Officer concluded that as of March 31, 2026, the Company’s internal controls were effective to ensure that information required to be disclosed by the Company in reports that it files or submits under the Securities and Exchange Act of 1934 is recorded, processed, summarized, and reported within the time periods specified.

There were no changes in the Company’s internal controls over financial reporting during the quarter ended March 31, 2026, that have materially affected, or are reasonably likely to materially affect, the Company’s internal control over financial reporting.

The design of any system of controls and procedures is based in part upon certain assumptions about the likelihood of future events. There can be no assurance that any design will succeed in achieving its stated goals under all potential future conditions, regardless of how remote.

62

Table of Contents

PART II - OTHER INFORMATION

Item 1. Legal Proceedings

The Company and its subsidiaries, from time to time, are involved in collection suits in the ordinary course of business against its debtors and are defendants in legal actions arising from normal business activities. Management, after consultation with legal counsel, believes that the ultimate liabilities, if any, resulting from these actions will not have a material adverse effect on the financial position of the Bank or on the consolidated financial position of the Company.

Item 1A. Risk Factors

Investing in shares of our common stock involves certain risks, including those identified and described in Item 1A of our Annual Report on Form 10-K for the fiscal year ended December 31, 2025, as well as cautionary statements contained in this Quarterly Report, on Form 10-Q, including those under the caption “Cautionary Note Regarding Forward-Looking Statements.”

There have been no material changes to the risk factors previously disclosed in our Annual Report on Form 10-K for the fiscal year ended December 31, 2025.

Item 2. Unregistered Sales of Equity Securities and Use of Proceeds

Stock Repurchases

In January 2026, our board of directors authorized the repurchase of up to 1,908,042 shares of our common stock (the “Repurchase Program”). The Company received notice of non-objection in January 2026 from the Federal Reserve Bank of Chicago for the Repurchase Program. Under the Repurchase Program, repurchases may be made through December 31, 2026 will not exceed an aggregate value of $43.9 million. We may make repurchases under the Repurchase Program from time to time through open market purchases, trading plans established in accordance with SEC rules, privately negotiated transactions, or by other means.

The actual means and timing of any repurchases, quantity of purchased shares and prices will be, subject to certain limitations, at the discretion of management and will depend on a number of factors, including, without limitation, market prices of our common stock, general market and economic conditions, and applicable legal and regulatory requirements. Repurchases under the Repurchase Program may be initiated, discontinued, suspended or restarted at any time provided that repurchases under the Repurchase Program, after December 31, 2026, would require Federal Reserve non-objection or approval. We are not obligated to repurchase any shares under the Repurchase Program.

During the first quarter of 2026, the Company repurchased 1,175,859 shares at $19.63 per share for a total reduction to capital of $23.1 million, as these shares are held in treasury stock.

The following table presents our stock repurchases for the quarter ended March 31, 2026:

Total Number of

Maximum Number

Total

Shares Purchased

of Shares that May

Number of

Average

as Part of Publicly

Yet Be

Shares

Price Paid

Announced Plans

Purchased Under

Purchased (a)

per Share (b)

or Programs (c)1

the Plans or Programs (d)

January 1, 2026 - January 31, 2026

-

$

-

-

1,908,042

February 1, 2026 - February 28, 2026

205,458

19.78

205,458

1,702,584

March 1, 2026 - March 31, 2026

970,401

19.60

970,401

732,183

Total

1,175,859

$

19.63

1,175,859

732,183

1 We announced our Repurchase Program, which will expire on December 31, 2026, unless further extended as described above, in our Current Report on Form 8-K filed on January 29, 2026, and 732,183 shares remained available for repurchase under the Repurchase Program as of March 31, 2026.

Item 3. Defaults Upon Senior Securities

None.

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Table of Contents

Item 4. Mine Safety Disclosures

Not applicable.

Item 5. Other Information

Trading Plans

During the three months ended March 31, 2026, neither the Company, nor any director or “officer” of the Company, adopted or terminated a “Rule 10b5-1 trading arrangement” or a “non-Rule 10b5-1 trading arrangement,” as each term is defined in Item 408(a) of Regulation S-K.

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Table of Contents

Item 6. Exhibits

Exhibits:

31.1

Certification of Chief Executive Officer Pursuant to Rule 13a-14(a)/15d-14(a).

31.2

Certification of Chief Financial Officer Pursuant to Rule 13a-14(a)/15d-14(a).

32.1

Certification of Chief Executive Officer Pursuant to 18 U.S.C. Section 1350, as Adopted Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002.

32.2

Certification of Chief Financial Officer Pursuant to 18 U.S.C. Section 1350, as Adopted Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002.

101

Interactive data files pursuant to Rule 405 of Regulation S-T: (i) Consolidated Balance Sheets at March 31, 2026, and December 31, 2025; (ii) Consolidated Statements of Income for the three months ended March 31, 2026 and 2025; (iii) Consolidated Statements of Comprehensive Income (Loss) for the three months ended March 31, 2026 and 2025; (iv) Consolidated Statements of Cash Flows for the three months ended March 31, 2026 and 2025; (v) Consolidated Statements of Stockholders’ Equity for the three months ended March 31, 2026 and 2025; and (vi) Notes to Consolidated Financial Statements, tagged as blocks of text and in detail.

104

Cover Page Interactive Data File (the cover page XBRL tags are embedded within the Inline XBRL document).

+ Schedules and similar attachments have been omitted pursuant to Item 601(b)(2) of Regulation S-K. The Registrant will furnish supplementally a copy of any omitted schedules or similar attachment to the SEC upon request.

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Table of Contents

SIGNATURES

Pursuant to the requirements of the Securities and Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

OLD SECOND BANCORP, INC.

BY:

/s/ James L. Eccher

James L. Eccher

Chairman, President and Chief Executive Officer

(principal executive officer)

BY:

/s/ Bradley S. Adams

Bradley S. Adams

Executive Vice President,

Chief Operating Officer and Chief Financial Officer

(principal financial and accounting officer)

DATE: May 7, 2026

66

FAQ

How did Old Second Bancorp (OSBC) perform financially in Q1 2026?

Old Second Bancorp generated net income of $25.6 million in Q1 2026, up from $19.8 million a year earlier. Basic earnings per share rose to $0.49 from $0.44, driven mainly by higher net interest and dividend income and increased noninterest income.

What happened to Old Second Bancorp’s net interest income in the quarter?

Net interest and dividend income grew to $81.1 million in Q1 2026 from $62.9 million in Q1 2025. Total interest income increased as loans and securities produced more revenue, while interest expense also rose because of higher rates on deposits and borrowings.

How did credit quality and loan losses trend for Old Second Bancorp in Q1 2026?

Credit costs increased significantly. The provision for credit losses reached $9.5 million, up from $2.4 million, and net charge-offs totaled $10.8 million. Key items included a $3.9 million commercial real estate charge-off and higher powersport loan charge-offs.

What were Old Second Bancorp’s loans, deposits, and assets at March 31, 2026?

At March 31, 2026, Old Second Bancorp reported total assets of $6.85 billion, total loans of $5.19 billion, and total deposits of $5.56 billion. These balances reflect the integration of the Bancorp Financial acquisition completed in 2025.

What is Old Second Bancorp’s allowance for credit losses and nonaccrual balance?

The allowance for credit losses on loans was $72.1 million at March 31, 2026, with an additional $2.0 million allowance on unfunded commitments. Nonaccrual loans totaled $62.6 million, compared with $48.0 million at December 31, 2025.

Did Old Second Bancorp pay dividends or repurchase stock in Q1 2026?

Yes. Old Second Bancorp declared a quarterly cash dividend of $0.07 per share and paid $3.7 million in common dividends. It also repurchased shares, increasing treasury stock to $26.2 million, including purchases under a stock repurchase program and tax-related share withholding.

What notable capital or funding actions did Old Second Bancorp take after Q1 2026?

On April 15, 2026, Old Second redeemed $30.0 million of its $60.0 million subordinated debt as the instrument transitioned from a 3.50% fixed rate to a SOFR-based floating rate, reducing outstanding subordinated borrowings.