Mercantile Bank (NASDAQ: MBWM) corrects 2026 metrics in Q4 2025 presentation

Rhea-AI Filing Summary

Mercantile Bank Corporation amended its previously furnished fourth quarter 2025 earnings materials to correct certain performance metrics in an investor presentation. The revised presentation updates 2026 figures for overhead costs in the first through fourth quarters and fee income in the third and fourth quarters on slide 26. All other information from the original fourth quarter and full-year 2025 materials remains unchanged. The updated Conference Call & Webcast Presentation is being used for the Fourth Quarter 2025 conference call and future investor and stakeholder presentations and is available as an exhibit and on the company’s investor relations website.

Q4 Earnings Release Amended true 0001042729 0001042729 2026-01-20 2026-01-20

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K/A

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the

Securities Exchange Act of 1934

Date of Report (date of earliest event reported): January 20, 2026

Mercantile Bank Corporation

(Exact name of registrant as specified in its charter)

Michigan	000-26719	38-3360865
(State or other jurisdiction  of incorporation)	(Commission File  Number)	(IRS Employer  Identification Number)

310 Leonard Street NW, Grand Rapids, Michigan	49504
(Address of principal executive offices)	(Zip Code)
Registrant's telephone number, including area code	616-406-3000

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

☐ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

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	MBWM	The Nasdaq Stock Market LLC

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (17 CFR §230.405) or Rule 12b-2 of the Securities Exchange Act of 1934 (17 CFR §240.12b-2).

Emerging 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.          ☐

EXPLANATORY NOTE

On January 20, 2026, Mercantile Bank Corporation (the “Company”) furnished a Current Report on Form 8-K (the “Original Report”) to the Securities and Exchange Commission (the “SEC”) announcing its financial results for its fourth quarter and year ended December 31, 2025, which Original Report included presentation materials that management intends to use during its Fourth Quarter 2025 conference call on Tuesday, January 20, 2026 at 10:00 am Eastern Time, and from time to time thereafter in presentations about the Company’s operations and performance (the “Original Presentation”) as Exhibit 99.2.

This Current Report on Form 8-K/A amends the Original Report to furnish a revised version of the Original Presentation (the “Revised Presentation”) to correct the reported performance metrics for 2026 for overhead costs in the first through fourth quarter and fee income in the third and fourth quarter on slide 26. Other than correcting this error in the Revised Presentation, all other information included in the Original Report is unchanged. The Revised Presentation is furnished with this Amendment as Exhibit 99.1 hereto.

Item 7.01 Regulation FD Disclosure.

The Company has prepared presentation materials (the “Conference Call & Webcast Presentation”) that management intends to use during its previously announced Fourth Quarter 2025 conference call on Tuesday, January 20, 2026 at 10:00 am Eastern Time, and from time to time thereafter in presentations about the Company’s operations and performance. The Company may use the Conference Call & Webcast Presentation, possibly with modifications, in presentations to current and potential investors, analysts, lenders, business partners, acquisition candidates, customers, employees and others with an interest in the Company and its business.

A copy of the Conference Call & Webcast Presentation is furnished as Exhibit 99.1 to this report and incorporated here by reference.  The Conference Call & Webcast Presentation is also available on the Company's website at http://ir.mercbank.com. Materials on the Company’s website are not part of or incorporated by reference into this report.

In accordance with General Instruction B.2 of Form 8-K, the information in this Current Report on Form 8-K, including Exhibit 99.1, shall not be deemed to be “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liability of that section, and shall not be incorporated by reference into any registration statement or other document filed under the Securities Act of 1933, as amended, or the Exchange Act, except as shall be expressly set forth by specific reference in such filing.

Item 9.01 Financial Statements and Exhibits.

(d) Exhibits.

Exhibit Number                    Description

99.1 Mercantile Bank Corporation Conference Call & Webcast Presentation dated January 20, 2026 (as revised).

104 Cover Page Interactive Data File (embedded within the Inline XBRL document)

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Signatures

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

	Mercantile Bank Corporation
	By:	/s/ Charles E. Christmas
		Charles E. Christmas
		Executive Vice President, Chief
		Financial Officer and Treasurer

Date: January 20, 2026

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FAQ

What did Mercantile Bank Corporation (MBWM) change in its amended Q4 2025 materials?

Mercantile Bank Corporation furnished a revised investor presentation to correct reported 2026 performance metrics for overhead costs in the first through fourth quarters and fee income in the third and fourth quarters on slide 26. All other information in the original materials remains the same.

Does the Mercantile Bank (MBWM) amendment change previously reported Q4 2025 financial results?

The amendment only corrects certain 2026 overhead cost and fee income performance metrics shown on slide 26 of the investor presentation. The company states that all other information in the original fourth quarter and year-end 2025 report is unchanged.

What presentation did Mercantile Bank (MBWM) update with this amendment?

The company updated its Conference Call & Webcast Presentation, originally furnished in connection with the Fourth Quarter 2025 conference call. The revised version is furnished as Exhibit 99.1 and may be used in future presentations to investors and other stakeholders.

Where can investors find Mercantile Bank’s (MBWM) revised Q4 2025 presentation?

The revised Conference Call & Webcast Presentation is furnished as Exhibit 99.1 and is also available on Mercantile Bank Corporation’s investor relations website at http://ir.mercbank.com, though website materials are not incorporated by reference into the report.

Does the Mercantile Bank (MBWM) amendment affect liability under the Exchange Act?

The company states that, under applicable instructions, the information in this current report, including Exhibit 99.1, is furnished and not deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, or incorporated into other filings unless specifically referenced.