[10-Q] IRON MOUNTAIN INC Quarterly Earnings Report

Rhea-AI Filing Summary

Iron Mountain (IRM) reported stronger Q3 2025 results. Revenue rose to $1.754 billion from $1.557 billion, led by storage rental ($1.033 billion) and services ($0.721 billion). Operating income increased to $308.6 million from $251.2 million. Net income attributable to IRM was $84.3 million, reversing a loss of $33.6 million a year ago, with diluted EPS of $0.28.

Year-to-date, revenue reached $5.059 billion versus $4.569 billion. Operating cash flow was $840.0 million, while capital expenditures were $1.755 billion as the company expanded capacity. IRM issued €1.2 billion of 4.75% Euro senior notes due 2034, using $1,390,651 in net proceeds to repay revolver borrowings and to repay GBP notes in Q4. Long‑term debt rose to $15.494 billion from $13.004 billion, and property, plant and equipment, net climbed to $9.138 billion from $7.632 billion. Data center storage rental revenue grew to $201.4 million in Q3 from $150.8 million. A dividend of $0.785 per share was paid for Q3, and a $0.864 dividend was declared for payment on January 6, 2026.

Insights

REIT and Capital Structure Analyst

Solid Q3 rebound; higher leverage funds growth.

Iron Mountain posted a clean swing to profitability in Q3 with revenue of $1.754B and EPS of $0.28, supported by storage and expanding data center rents. Operating income grew while SG&A held roughly steady year over year.

Growth is being funded with sizable capex and new debt. YTD operating cash flow was $840.0M against capex of $1.755B. Long‑term debt increased to $15.494B, and the company issued €1.2B notes due 2034 at 4.75% to term out borrowings and address near‑term GBP notes.

Execution hinges on continued data center ramp and maintaining covenant compliance, which management states is in place as of September 30, 2025. The declared dividend of $0.864 per share adds income appeal, with sustainability tied to cash generation and funding plans.

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Table of Contents

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, DC 20549

FORM 10-Q

(Mark One)
☒			QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the Quarterly Period Ended September 30, 2025

OR
☐			TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
For the Transition Period from                        to

Commission file number 1-13045

IRON MOUNTAIN INCORPORATED

(Exact Name of Registrant as Specified in Its Charter)

Delaware			23-2588479
(State or other Jurisdiction of Incorporation or Organization)			(I.R.S. Employer Identification No.)

    

85 New Hampshire Avenue, Suite 150, Portsmouth, New Hampshire 03801

(Address of Principal Executive Offices, Including Zip Code)

(617) 535-4766

(Registrant's Telephone Number, Including Area Code)

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

Title of each class

Trading Symbol(s)

Name of each exchange on which registered

Common Stock, $.01 par value

IRM

NYSE

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 during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). Yes ☒    No ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a 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. (Check one):

Large accelerated filer			☒			Accelerated filer			☐
Non-accelerated filer			☐			Smaller reporting company			☐
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. ☐

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes ☐    No ☒

As of October 31, 2025, the registrant had 295,589,491 outstanding shares of common stock, $.01 par value.

Table of Contents

IRON MOUNTAIN INCORPORATED

2025 FORM 10-Q QUARTERLY REPORT

TABLE OF CONTENTS

PART I—FINANCIAL INFORMATION
			1			ITEM 1.			Unaudited Condensed Consolidated Financial Statements
						2			Condensed Consolidated Balance Sheets at September 30, 2025 and December 31, 2024
						3			Condensed Consolidated Statements of Operations for the Three Months Ended September 30, 2025 and 2024
						4			Condensed Consolidated Statements of Operations for the Nine Months Ended September 30, 2025 and 2024
						5			Condensed Consolidated Statements of Comprehensive Income (Loss) for the Three and Nine Months Ended September 30, 2025 and 2024
						6			Condensed Consolidated Statements of (Deficit) Equity for the Three and Nine Months Ended September 30, 2025
						7			Condensed Consolidated Statements of (Deficit) Equity for the Three and Nine Months Ended September 30, 2024
						8			Condensed Consolidated Statements of Cash Flows for the Nine Months Ended September 30, 2025 and 2024
						9			Notes to Condensed Consolidated Financial Statements
			29			ITEM 2.			Management's Discussion and Analysis of Financial Condition and Results of Operations
			49			ITEM 4.			Controls and Procedures
PART II—OTHER INFORMATION
			51			ITEM 2.			Unregistered Sales of Equity Securities and Use of Proceeds
			51			ITEM 5.			Other Information
			51			ITEM 6.			Exhibits
			52			Signatures

Table of Contents

PART I. FINANCIAL INFORMATION

ITEM 1. UNAUDITED CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

IRON MOUNTAIN SEPTEMBER 30, 2025 FORM 10-Q 1

Table of Contents

Part I. Financial Information

IRON MOUNTAIN INCORPORATED

CONDENSED CONSOLIDATED BALANCE SHEETS

(IN THOUSANDS, EXCEPT SHARE AND PER SHARE DATA) (UNAUDITED)

			SEPTEMBER 30, 2025						DECEMBER 31, 2024
ASSETS
Current Assets:
Cash and cash equivalents			$	195,210					$	155,716
Accounts receivable (less allowances of $106,587 and $86,712 as of September 30, 2025 and December 31, 2024, respectively)			1,371,367						1,291,379
Prepaid expenses and other			314,293						244,127
Total Current Assets			1,880,870						1,691,222
Property, Plant and Equipment:
Property, plant and equipment			13,975,948						11,985,997
Less—Accumulated depreciation			(4,838,448)						(4,354,398)
Property, Plant and Equipment, Net			9,137,500						7,631,599
Other Assets, Net:
Goodwill			5,269,541						5,083,817
Customer and supplier relationships and other intangible assets			1,253,919						1,274,731
Operating lease right-of-use assets			2,455,450						2,489,893
Other			635,573						545,853
Total Other Assets, Net			9,614,483						9,394,294
Total Assets			$	20,632,853					$	18,717,115
LIABILITIES AND EQUITY
Current Liabilities:
Current portion of long-term debt			$	699,320					$	715,109
Accounts payable			658,138						678,716
Accrued expenses and other current liabilities (includes current portion of operating lease liabilities)			1,151,107						1,366,568
Deferred revenue			347,018						326,882
Total Current Liabilities			2,855,583						3,087,275
Long-term Debt, net of current portion			15,494,236						13,003,977
Long-term Operating Lease Liabilities, net of current portion			2,283,504						2,334,826
Other Long-term Liabilities			389,106						312,199
Deferred Income Taxes			218,223						205,341
Commitments and Contingencies
Redeemable Noncontrolling Interests			75,353						78,171
(Deficit) Equity:
Iron Mountain Incorporated Stockholders' (Deficit) Equity:
Preferred stock (par value $0.01; authorized 10,000,000 shares; none issued and outstanding)			—						—
Common stock (par value $0.01; authorized 400,000,000 shares; issued and outstanding 295,504,799 and 293,592,637 shares as of September 30, 2025 and December 31, 2024, respectively)			2,955						2,936
Additional paid-in capital			4,730,575						4,647,330
(Distributions in excess of earnings) Earnings in excess of distributions			(5,236,868)						(4,583,436)
Accumulated other comprehensive items, net			(378,624)						(569,952)
Total Iron Mountain Incorporated Stockholders' (Deficit) Equity			(881,962)						(503,122)
Noncontrolling Interests			198,810						198,448
Total (Deficit) Equity			(683,152)						(304,674)
Total Liabilities and (Deficit) Equity			$	20,632,853					$	18,717,115

The accompanying notes are an integral part of these condensed consolidated financial statements.

IRON MOUNTAIN SEPTEMBER 30, 2025 FORM 10-Q 2

Table of Contents

Part I. Financial Information

IRON MOUNTAIN INCORPORATED

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS

(IN THOUSANDS, EXCEPT PER SHARE DATA) (UNAUDITED)

			THREE MONTHS ENDED SEPTEMBER 30,
			2025						2024
Revenues:
Storage rental			$	1,032,897					$	935,701
Service			721,196						621,657
Total Revenues			1,754,093						1,557,358
Operating Expenses:
Cost of sales (excluding depreciation and amortization)			791,939						678,390
Selling, general and administrative			335,248						341,929
Depreciation and amortization			262,203						232,240
Acquisition and Integration Costs			5,402						11,262
Restructuring and other transformation			47,346						37,282
Loss (gain) on disposal/write-down of property, plant and equipment, net			3,366						5,091
Total Operating Expenses			1,445,504						1,306,194
Operating Income (Loss)			308,589						251,164
Interest Expense, Net (includes Interest Income of $8,061 and $949 for the three months ended September 30, 2025 and 2024, respectively)			209,740						186,067
Other (Income) Expense, Net			(3,986)						86,362
Net Income (Loss) Before Provision (Benefit) for Income Taxes			102,835						(21,265)
Provision (Benefit) for Income Taxes			16,594						12,400
Net Income (Loss)			86,241						(33,665)
Less: Net Income (Loss) Attributable to Noncontrolling Interests			1,951						(45)
Net Income (Loss) Attributable to Iron Mountain Incorporated			$	84,290					$	(33,620)
Net Income (Loss) Per Share Attributable to Iron Mountain Incorporated:
Basic			$	0.28					$	(0.11)
Diluted			$	0.28					$	(0.11)
Weighted Average Common Shares Outstanding—Basic			295,771						293,603
Weighted Average Common Shares Outstanding—Diluted			297,981						293,603

The accompanying notes are an integral part of these condensed consolidated financial statements.

IRON MOUNTAIN SEPTEMBER 30, 2025 FORM 10-Q 3

Table of Contents

Part I. Financial Information

IRON MOUNTAIN INCORPORATED

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS

(IN THOUSANDS, EXCEPT PER SHARE DATA) (UNAUDITED)

			NINE MONTHS ENDED SEPTEMBER 30,
			2025						2024
Revenues:
Storage rental			$	2,991,262					$	2,740,289
Service			2,067,308						1,828,341
Total Revenues			5,058,570						4,568,630
Operating Expenses:
Cost of sales (excluding depreciation and amortization)			2,256,980						2,007,616
Selling, general and administrative			1,055,441						1,006,232
Depreciation and amortization			746,923						666,296
Acquisition and Integration Costs			16,040						28,573
Restructuring and other transformation			152,432						124,562
Loss (gain) on disposal/write-down of property, plant and equipment, net			7,975						8,270
Total Operating Expenses			4,235,791						3,841,549
Operating Income (Loss)			822,779						727,081
Interest Expense, Net (includes Interest Income of $15,966 and $4,374 for the nine months ended September 30, 2025 and 2024, respectively)			609,541						527,107
Other Expense (Income), Net			106,379						79,665
Net Income (Loss) Before Provision (Benefit) for Income Taxes			106,859						120,309
Provision (Benefit) for Income Taxes			47,725						42,328
Net Income (Loss)			59,134						77,981
Less: Net Income (Loss) Attributable to Noncontrolling Interests			3,813						1,757
Net Income (Loss) Attributable to Iron Mountain Incorporated			$	55,321					$	76,224
Net Income (Loss) Per Share Attributable to Iron Mountain Incorporated:
Basic			$	0.19					$	0.26
Diluted			$	0.19					$	0.26
Weighted Average Common Shares Outstanding—Basic			295,214						293,229
Weighted Average Common Shares Outstanding—Diluted			297,628						295,912

The accompanying notes are an integral part of these condensed consolidated financial statements.

IRON MOUNTAIN SEPTEMBER 30, 2025 FORM 10-Q 4

Table of Contents

Part I. Financial Information

IRON MOUNTAIN INCORPORATED

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS)

(IN THOUSANDS) (UNAUDITED)

			THREE MONTHS ENDED SEPTEMBER 30,
			2025						2024
Net Income (Loss)			$	86,241					$	(33,665)
Other Comprehensive (Loss) Income:
Foreign Currency Translation Adjustment			(15,178)						107,282
Change in Fair Value of Interest Rate Swaps			(72)						(34,281)
Total Other Comprehensive (Loss) Income			(15,250)						73,001
Comprehensive Income (Loss)			70,991						39,336
Comprehensive Income (Loss) Attributable to Noncontrolling Interests			1,742						376
Comprehensive Income (Loss) Attributable to Iron Mountain Incorporated			$	69,249					$	38,960

        

			NINE MONTHS ENDED SEPTEMBER 30,
			2025						2024
Net Income (Loss)			$	59,134					$	77,981
Other Comprehensive Income (Loss):
Foreign Currency Translation Adjustment			199,630						8,434
Change in Fair Value of Interest Rate Swaps			(8,090)						(23,381)
Reclassifications from Accumulated Other Comprehensive Items, net			—						(2,528)
Total Other Comprehensive Income (Loss)			191,540						(17,475)
Comprehensive Income (Loss)			250,674						60,506
Comprehensive Income (Loss) Attributable to Noncontrolling Interests			4,025						1,637
Comprehensive Income (Loss) Attributable to Iron Mountain Incorporated			$	246,649					$	58,869

The accompanying notes are an integral part of these condensed consolidated financial statements.

IRON MOUNTAIN SEPTEMBER 30, 2025 FORM 10-Q 5

Table of Contents

Part I. Financial Information

IRON MOUNTAIN INCORPORATED

CONDENSED CONSOLIDATED STATEMENTS OF (DEFICIT) EQUITY

(IN THOUSANDS, EXCEPT SHARE DATA) (UNAUDITED)

THREE MONTHS ENDED SEPTEMBER 30, 2025
									IRON MOUNTAIN INCORPORATED STOCKHOLDERS' (DEFICIT) EQUITY
									COMMON STOCK												ADDITIONAL PAID-IN CAPITAL						(DISTRIBUTIONS IN EXCESS OF EARNINGS) EARNINGS IN EXCESS OF DISTRIBUTIONS						ACCUMULATED OTHER COMPREHENSIVE ITEMS, NET						NONCONTROLLING INTERESTS									REDEEMABLE NONCONTROLLING INTERESTS
			TOTAL						SHARES						AMOUNTS
Balance, June 30, 2025			$	(568,867)					295,271,945						$	2,953					$	4,680,581					$	(5,087,387)					$	(363,583)					$	198,569								$	76,852
Issuance and net settlement of shares under employee stock purchase and option plans and stock-based compensation			49,996						232,854						2						49,994						—						—						—									—
Parent cash dividends declared			(233,771)						—						—						—						(233,771)						—						—									—
Other comprehensive (loss) income			(15,041)						—						—						—						—						(15,041)						—									(209)
Net income (loss)			86,862						—						—						—						84,290						—						2,572									(621)
Noncontrolling interests dividends			(2,331)						—						—						—						—						—						(2,331)									(669)
Balance, September 30, 2025			$	(683,152)					295,504,799						$	2,955					$	4,730,575					$	(5,236,868)					$	(378,624)					$	198,810								$	75,353
NINE MONTHS ENDED SEPTEMBER 30, 2025
									IRON MOUNTAIN INCORPORATED STOCKHOLDERS' (DEFICIT) EQUITY
									COMMON STOCK												ADDITIONAL PAID-IN CAPITAL						(DISTRIBUTIONS IN EXCESS OF EARNINGS) EARNINGS IN EXCESS OF DISTRIBUTIONS						ACCUMULATED OTHER COMPREHENSIVE ITEMS, NET						NONCONTROLLING INTERESTS									REDEEMABLE NONCONTROLLING INTERESTS
			TOTAL						SHARES						AMOUNTS
Balance, December 31, 2024			$	(304,674)					293,592,637						$	2,936					$	4,647,330					$	(4,583,436)					$	(569,952)					$	198,448								$	78,171
Issuance and net settlement of shares under employee stock purchase and option plans and stock-based compensation			83,324						1,912,162						19						83,305						—						—						—									—
Parent cash dividends declared			(708,753)						—						—						—						(708,753)						—						—									—
Other comprehensive income (loss)			191,328						—						—						—						—						191,328						—									212
Net income (loss)			60,196						—						—						—						55,321						—						4,875									(1,062)
Noncontrolling interests equity contributions			(60)						—						—						(60)						—						—						—									—
Noncontrolling interests dividends			(4,513)						—						—						—						—						—						(4,513)									(1,968)
Balance, September 30, 2025			$	(683,152)					295,504,799						$	2,955					$	4,730,575					$	(5,236,868)					$	(378,624)					$	198,810								$	75,353

The accompanying notes are an integral part of these condensed consolidated financial statements.

IRON MOUNTAIN SEPTEMBER 30, 2025 FORM 10-Q 6

Table of Contents

Part I. Financial Information

IRON MOUNTAIN INCORPORATED

CONDENSED CONSOLIDATED STATEMENTS OF (DEFICIT) EQUITY

(IN THOUSANDS, EXCEPT SHARE DATA) (UNAUDITED)

THREE MONTHS ENDED SEPTEMBER 30, 2024
									IRON MOUNTAIN INCORPORATED STOCKHOLDERS' (DEFICIT) EQUITY
									COMMON STOCK												ADDITIONAL PAID-IN CAPITAL						(DISTRIBUTIONS IN EXCESS OF EARNINGS) EARNINGS IN EXCESS OF DISTRIBUTIONS						ACCUMULATED OTHER COMPREHENSIVE ITEMS, NET						NONCONTROLLING INTERESTS									REDEEMABLE NONCONTROLLING INTERESTS
			TOTAL						SHARES						AMOUNTS
Balance, June 30, 2024			$	(132,749)					293,298,465						$	2,933					$	4,555,883					$	(4,230,599)					$	(461,091)					$	125								$	184,861
Issuance and net settlement of shares under employee stock purchase and option plans and stock-based compensation			32,928						126,800						1						32,927						—						—						—									—
Changes in equity related to redeemable noncontrolling interests			(1,036)						—						—						(54,446)						—						—						53,410									(113,964)
Parent cash dividends declared			(211,463)						—						—						—						(211,463)						—						—									—
Other comprehensive income (loss)			72,580						—						—						—						—						72,580						—									421
Net (loss) income			(33,620)						—						—						—						(33,620)						—						—									(45)
Noncontrolling interests equity contributions and related costs			170,952						—						—						67,882						—						—						103,070									—
Noncontrolling interests dividends			—						—						—						—						—						—						—									(736)
Balance, September 30, 2024			$	(102,408)					293,425,265						$	2,934					$	4,602,246					$	(4,475,682)					$	(388,511)					$	156,605								$	70,537
NINE MONTHS ENDED SEPTEMBER 30, 2024
									IRON MOUNTAIN INCORPORATED STOCKHOLDERS' (DEFICIT) EQUITY
									COMMON STOCK												ADDITIONAL PAID-IN CAPITAL						(DISTRIBUTIONS IN EXCESS OF EARNINGS) EARNINGS IN EXCESS OF DISTRIBUTIONS						ACCUMULATED OTHER COMPREHENSIVE ITEMS, NET						NONCONTROLLING INTERESTS									REDEEMABLE NONCONTROLLING INTERESTS
			TOTAL						SHARES						AMOUNTS
Balance, December 31, 2023			$	211,773					292,142,739						$	2,921					$	4,533,691					$	(3,953,808)					$	(371,156)					$	125								$	177,947
Issuance and net settlement of shares under employee stock purchase and option plans and stock-based compensation			54,710						1,282,526						13						54,697						—						—						—									—
Changes in equity related to redeemable noncontrolling interests			(614)						—						—						(54,024)						—						—						53,410									(107,102)
Parent cash dividends declared			(598,098)						—						—						—						(598,098)						—						—									—
Other comprehensive (loss) income			(17,355)						—						—						—						—						(17,355)						—									(120)
Net income (loss)			76,224						—						—						—						76,224						—						—									1,757
Noncontrolling interests equity contributions and related costs			170,952						—						—						67,882						—						—						103,070									—
Noncontrolling interests dividends			—						—						—						—						—						—						—									(1,945)
Balance, September 30, 2024			$	(102,408)					293,425,265						$	2,934					$	4,602,246					$	(4,475,682)					$	(388,511)					$	156,605								$	70,537

The accompanying notes are an integral part of these condensed consolidated financial statements.

IRON MOUNTAIN SEPTEMBER 30, 2025 FORM 10-Q 7

Table of Contents

Part I. Financial Information

IRON MOUNTAIN INCORPORATED

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS

(IN THOUSANDS) (UNAUDITED)

			NINE MONTHS ENDED SEPTEMBER 30,
			2025						2024
Cash Flows from Operating Activities:
Net Income (Loss)			$	59,134					$	77,981
Adjustments to reconcile net income (loss) to cash flows from operating activities:
Depreciation			532,468						466,905
Amortization (includes amortization of deferred financing costs and discounts of $24,419 and $18,909 for the nine months ended September 30, 2025 and 2024, respectively)			238,874						218,300
Revenue reduction associated with amortization of customer inducements and above- and below-market leases			4,468						4,117
Stock-based compensation expense			118,595						73,491
(Benefit) provision for deferred income taxes			(9,767)						(9,012)
Loss on early extinguishment of debt			—						5,417
Loss (gain) on disposal/write-down of property, plant and equipment, net			7,975						8,270
Foreign currency transactions and other, net			47,117						100,436
(Increase) decrease in assets			(155,859)						(45,677)
(Decrease) increase in liabilities			(3,004)						(135,100)
Cash Flows from Operating Activities			840,001						765,128
Cash Flows from Investing Activities:
Capital expenditures			(1,755,383)						(1,173,968)
Cash paid for acquisitions, net of cash acquired			(101,625)						(174,445)
Acquisition of customer intangibles			(21,204)						(5,820)
Contract costs			(59,607)						(84,112)
Investments in joint ventures and other investments, net			(43,309)						(9,834)
Proceeds from sales of property and equipment and other, net			12,869						6,350
Cash Flows from Investing Activities			(1,968,259)						(1,441,829)
Cash Flows from Financing Activities:
Repayment of revolving credit facility, term loan facilities and other debt			(12,747,897)						(8,974,574)
Proceeds from revolving credit facility, term loan facilities and other debt			13,546,589						10,247,884
Net proceeds from sale of senior note			1,390,651						—
Equity contributions from noncontrolling interests			—						178,616
Equity distributions to noncontrolling interests			(6,481)						(1,945)
Repurchase of noncontrolling interest			—						(35,203)
Parent cash dividends			(687,204)						(579,494)
Payment of deferred purchase obligations and other deferred payments			(240,217)						(158,677)
Net (payments) proceeds associated with employee stock-based awards			(46,415)						(18,781)
Other, net			(7,831)						(18,625)
Cash Flows from Financing Activities			1,201,195						639,201
Effect of Exchange Rates on Cash and Cash Equivalents			(33,443)						(16,774)
Increase (Decrease) in Cash and Cash Equivalents			39,494						(54,274)
Cash and Cash Equivalents, Beginning of Period			155,716						222,789
Cash and Cash Equivalents, End of Period			$	195,210					$	168,515
Supplemental Information:
Cash Paid for Interest			$	711,517					$	644,301
Cash Paid for Income Taxes, Net			$	89,828					$	68,135
Non-Cash Investing and Financing Activities:
Financing Leases and Other			$	193,047					$	129,109
Accrued Capital Expenditures			$	247,224					$	241,240
Deferred Purchase Obligations and Other Deferred Payments			$	28,137					$	260,813
Dividends Payable			$	244,198					$	220,996

The accompanying notes are an integral part of these condensed consolidated financial statements.

IRON MOUNTAIN SEPTEMBER 30, 2025 FORM 10-Q 8

Table of Contents

Part I. Financial Information

IRON MOUNTAIN INCORPORATED

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

(In thousands, except share and per share data) (Unaudited)

1. GENERAL

The unaudited condensed consolidated financial statements of Iron Mountain Incorporated, a Delaware corporation, and its subsidiaries ("we" or "us"), have been prepared pursuant to the rules and regulations of the United States Securities and Exchange Commission (the "SEC"). Certain information and footnote disclosures normally included in the annual financial statements prepared in accordance with accounting principles generally accepted in the United States of America ("GAAP") have been omitted pursuant to those rules and regulations, but we believe that the disclosures included herein are adequate to make the information presented not misleading. The interim condensed consolidated financial statements are presented herein and, in the opinion of management, reflect all adjustments of a normal recurring nature necessary for a fair presentation. Interim results are not necessarily indicative of results for a full year.

The Condensed Consolidated Financial Statements and Notes thereto, which are included herein, should be read in conjunction with the Consolidated Financial Statements and Notes thereto for the year ended December 31, 2024 included in our Annual Report on Form 10-K filed with the SEC on February 14, 2025 (our "Annual Report").

In September 2022, we announced a global program designed to accelerate the growth of our business ("Project Matterhorn"). See Note 10.

We have been organized and have operated as a real estate investment trust for United States federal income tax purposes beginning with our taxable year ended December 31, 2014.

2. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

A. CASH AND CASH EQUIVALENTS

Cash and cash equivalents include cash on hand and cash invested in highly liquid short-term securities, which have remaining maturities at the date of purchase of less than 90 days. Cash and cash equivalents are carried at cost, which approximates fair value.

B. ACCOUNTS RECEIVABLE

We maintain an allowance for doubtful accounts and a credit memo reserve for estimated losses resulting from the potential inability of our customers to make required payments and potential disputes regarding billing and service issues. The rollforward of the allowance for doubtful accounts and credit memo reserves for the nine months ended September 30, 2025 is as follows:

						Balance as of December 31, 2024						$	86,712
						Credit memos charged to revenue						73,715
						Allowance for bad debts charged to expense						43,527
						Deductions and other(1)						(97,367)
						Balance as of September 30, 2025						$	106,587

(1)Primarily consists of the issuance of credit memos, the write-off of accounts receivable and the impact associated with currency translation adjustments.

IRON MOUNTAIN SEPTEMBER 30, 2025 FORM 10-Q 9

Table of Contents

Part I. Financial Information

IRON MOUNTAIN INCORPORATED

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (CONTINUED)

(In thousands, except share and per share data) (Unaudited)

2. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (CONTINUED)

C. LEASES

We lease facilities for certain warehouses, data centers and office space. We also have land leases, including those on which certain facilities are located.

Operating and financing lease right-of-use assets and lease liabilities as of September 30, 2025 and December 31, 2024 are as follows:

DESCRIPTION			SEPTEMBER 30, 2025						DECEMBER 31, 2024
Assets:
Operating lease right-of-use assets			$	2,455,450					$	2,489,893
Financing lease right-of-use assets, net of accumulated depreciation(1)			462,504						359,265
Liabilities:
Current
Operating lease liabilities			$	326,320					$	315,400
Financing lease liabilities(1)			54,123						128,397
Long-term
Operating lease liabilities			$	2,283,504					$	2,334,826
Financing lease liabilities(1)			461,446						278,444

(1)Financing lease right-of-use assets, current financing lease liabilities and long-term financing lease liabilities are included within Property, plant and equipment, net, Current portion of long-term debt and Long-term debt, net of current portion, respectively, within our Condensed Consolidated Balance Sheets.

The components of the lease expense for the three and nine months ended September 30, 2025 and 2024 are as follows:

			THREE MONTHS ENDED SEPTEMBER 30,												NINE MONTHS ENDED SEPTEMBER 30,
DESCRIPTION			2025						2024						2025						2024
Operating lease cost(1)			$	176,591					$	168,308					$	529,730					$	512,789
Financing lease cost:
Depreciation of financing lease right-of-use assets			$	16,737					$	13,907					$	45,715					$	36,929
Interest expense for financing lease liabilities			6,994						5,593						20,448						16,031

(1)Operating lease cost, the majority of which is included in Cost of sales, includes variable lease costs of $46,221 and $139,887 for the three and nine months ended September 30, 2025, respectively, and $42,785 and $120,473 for the three and nine months ended September 30, 2024, respectively.

Other information: Supplemental cash flow information relating to our leases for the nine months ended September 30, 2025 and 2024 is as follows:

			NINE MONTHS ENDED SEPTEMBER 30,
CASH PAID FOR AMOUNTS INCLUDED IN MEASUREMENT OF LEASE LIABILITIES:			2025						2024
Operating cash flows used in operating leases			$	371,753					$	355,509
Operating cash flows used in financing leases (interest)			20,448						16,031
Financing cash flows used in financing leases			41,478						41,079
NON-CASH ITEMS:
Operating lease modifications and reassessments			$	(10,137)					$	9,536
New operating leases (including acquisitions)			189,005						97,708

IRON MOUNTAIN SEPTEMBER 30, 2025 FORM 10-Q 10

Table of Contents

Part I. Financial Information

IRON MOUNTAIN INCORPORATED

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (CONTINUED)

(In thousands, except share and per share data) (Unaudited)

2. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (CONTINUED)

D. GOODWILL

Our reporting units as of December 31, 2024 are described in detail in Note 2.l. to Notes to Consolidated Financial Statements included in our Annual Report.

The changes in the carrying value of goodwill attributable to each reportable segment and Corporate and Other (as defined in Note 8) for the nine months ended September 30, 2025 are as follows:

			GLOBAL RIM BUSINESS						GLOBAL DATA CENTER BUSINESS												CORPORATE AND OTHER						TOTAL CONSOLIDATED
Goodwill balance, net of accumulated amortization, as of December 31, 2024			$	3,816,874					$	469,461											$	797,482					$	5,083,817
Tax deductible goodwill acquired during the period			—						—												17,620						17,620
Non-tax deductible goodwill acquired during the period			38,775						—												13,171						51,946
Fair value and other adjustments			—						—												(1,464)						(1,464)
Currency effects			100,136						13,997												3,489						117,622
Goodwill balance, net of accumulated amortization, as of September 30, 2025			$	3,955,785					$	483,458											$	830,298					$	5,269,541
Accumulated goodwill impairment balance as of September 30, 2025			$	132,409					$	—											$	26,011					$	158,420

IRON MOUNTAIN SEPTEMBER 30, 2025 FORM 10-Q 11

Table of Contents

Part I. Financial Information

IRON MOUNTAIN INCORPORATED

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (CONTINUED)

(In thousands, except share and per share data) (Unaudited)

2. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (CONTINUED)

E. FAIR VALUE MEASUREMENTS

The assets and liabilities carried at fair value and measured on a recurring basis as of September 30, 2025 and December 31, 2024 are as follows:

									FAIR VALUE MEASUREMENTS AS OF SEPTEMBER 30, 2025 USING
DESCRIPTION			TOTAL CARRYING VALUE AS OF SEPTEMBER 30, 2025						QUOTED PRICES IN ACTIVE MARKETS (LEVEL 1)						SIGNIFICANT OTHER OBSERVABLE INPUTS (LEVEL 2)						SIGNIFICANT UNOBSERVABLE INPUTS (LEVEL 3)(2)
Money Market Funds			$	5,125					$	—					$	5,125					$	—
Time Deposits			4,272						—						4,272						—
Trading Securities			7,814						6,010						1,804						—
Derivative Assets			243						—						243						—
Derivative Liabilities			68,230						—						68,230						—
Deferred Purchase Obligations(1)			114,578						—						—						114,578

									FAIR VALUE MEASUREMENTS AS OF DECEMBER 31, 2024 USING
DESCRIPTION			TOTAL CARRYING VALUE AS OF DECEMBER 31, 2024						QUOTED PRICES IN ACTIVE MARKETS (LEVEL 1)						SIGNIFICANT OTHER OBSERVABLE INPUTS (LEVEL 2)						SIGNIFICANT UNOBSERVABLE INPUTS (LEVEL 3)(2)
Money Market Funds			$	2,488					$	—					$	2,488					$	—
Time Deposits			9,612						—						9,612						—
Trading Securities			8,144						6,390						1,754						—
Derivative Assets			28,092						—						28,092						—
Derivative Liabilities			5,326						—						5,326						—
Deferred Purchase Obligations(1)			147,055						—						—						147,055

(1)The balance as of September 30, 2025 primarily relates to the fair value of the deferred purchase obligation associated with the Regency Transaction (as defined in Note 3 to Notes to Consolidated Financial Statements included in our Annual Report). The balance as of December 31, 2024 primarily relates to the fair values of the deferred purchase obligations associated with the Regency Transaction and ITRenew Transaction (as defined in Note 3 to Notes to Consolidated Financial Statements included in our Annual Report).

(2)The following is a rollforward of the Level 3 liabilities presented above for December 31, 2024 through September 30, 2025:

Balance as of December 31, 2024						$	147,055
Additions						16,626
Payments						(49,215)
Other changes, including accretion						112
Balance as of September 30, 2025						$	114,578

The level 3 valuation of the deferred purchase obligation was determined primarily utilizing a Monte-Carlo model which takes into account our forecasted projections as they relate to the underlying performance of the business. The Monte-Carlo simulation model incorporates assumptions as to expected revenue over the achievement period, including adjustments for volatility and timing, as well as discount rates that account for the risk of the arrangement and overall market risks. Any material change to these assumptions may result in a significantly higher or lower fair value of the deferred purchase obligation.

There were no material items that were measured at fair value on a non-recurring basis as of September 30, 2025 and December 31, 2024 other than those disclosed in Note 2.p. to Notes to Consolidated Financial Statements included in our Annual Report.

IRON MOUNTAIN SEPTEMBER 30, 2025 FORM 10-Q 12

Table of Contents

Part I. Financial Information

IRON MOUNTAIN INCORPORATED

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (CONTINUED)

(In thousands, except share and per share data) (Unaudited)

2. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (CONTINUED)

F. ACCUMULATED OTHER COMPREHENSIVE ITEMS, NET

The changes in Accumulated other comprehensive items, net for the three and nine months ended September 30, 2025 and 2024 are as follows:

			THREE MONTHS ENDED SEPTEMBER 30, 2025																		THREE MONTHS ENDED SEPTEMBER 30, 2024
			FOREIGN CURRENCY TRANSLATION AND OTHER ADJUSTMENTS						DERIVATIVE FINANCIAL INSTRUMENTS						TOTAL						FOREIGN CURRENCY TRANSLATION AND OTHER ADJUSTMENTS						DERIVATIVE FINANCIAL INSTRUMENTS						TOTAL
Beginning of Period			$	(353,742)					$	(9,841)					$	(363,583)					$	(471,935)					$	10,844					$	(461,091)
Other comprehensive (loss) income:
Foreign currency translation and other adjustments			(14,969)						—						(14,969)						106,861						—						106,861
Change in fair value of interest rate swaps			—						(72)						(72)						—						(34,281)						(34,281)
Total other comprehensive (loss) income			(14,969)						(72)						(15,041)						106,861						(34,281)						72,580
End of Period			$	(368,711)					$	(9,913)					$	(378,624)					$	(365,074)					$	(23,437)					$	(388,511)

			NINE MONTHS ENDED SEPTEMBER 30, 2025																		NINE MONTHS ENDED SEPTEMBER 30, 2024
			FOREIGN CURRENCY TRANSLATION AND OTHER ADJUSTMENTS						DERIVATIVE FINANCIAL INSTRUMENTS						TOTAL						FOREIGN CURRENCY TRANSLATION AND OTHER ADJUSTMENTS						DERIVATIVE FINANCIAL INSTRUMENTS						TOTAL
Beginning of Period			$	(568,129)					$	(1,823)					$	(569,952)					$	(373,628)					$	2,472					$	(371,156)
Other comprehensive income (loss):
Foreign currency translation and other adjustments			199,418						—						199,418						8,554						—						8,554
Change in fair value of interest rate swaps			—						(8,090)						(8,090)						—						(23,381)						(23,381)
Reclassifications from accumulated other comprehensive items, net			—						—						—						—						(2,528)						(2,528)
Total other comprehensive income (loss)			199,418						(8,090)						191,328						8,554						(25,909)						(17,355)
End of Period			$	(368,711)					$	(9,913)					$	(378,624)					$	(365,074)					$	(23,437)					$	(388,511)

G. REVENUES

Certain costs to fulfill or obtain customer contracts, including the costs associated with the initial movement of customer records into physical storage and certain commission expenses, and certain initial direct costs of obtaining data center leases are collectively referred to as "Contract Costs". Contract Costs are primarily made up of Intake Costs and Commissions (each as defined in Note 2.s. to Notes to Consolidated Financial Statements included in our Annual Report). Contract Costs as of September 30, 2025 and December 31, 2024 are as follows:

			SEPTEMBER 30, 2025																		DECEMBER 31, 2024
DESCRIPTION			GROSS CARRYING AMOUNT						ACCUMULATED AMORTIZATION						NET CARRYING AMOUNT						GROSS CARRYING AMOUNT						ACCUMULATED AMORTIZATION						NET CARRYING AMOUNT
Intake Costs asset			$	108,962					$	(54,780)					$	54,182					$	89,057					$	(43,783)					$	45,274
Commissions asset			229,940						(101,172)						128,768						200,149						(78,955)						121,194

IRON MOUNTAIN SEPTEMBER 30, 2025 FORM 10-Q 13

Table of Contents

Part I. Financial Information

IRON MOUNTAIN INCORPORATED

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (CONTINUED)

(In thousands, except share and per share data) (Unaudited)

2. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (CONTINUED)

Deferred revenue liabilities are reflected in our Condensed Consolidated Balance Sheets as follows:

DESCRIPTION			LOCATION IN BALANCE SHEET			SEPTEMBER 30, 2025						DECEMBER 31, 2024(1)
Deferred revenue—Current(2)			Deferred revenue			$	347,018					$	326,882
Deferred revenue—Long-term(3)			Other Long-term Liabilities			142,364						110,601

(1)    The beginning balance of current and long-term deferred revenue for the year ended December 31, 2024 was $325,665 and $100,770, respectively.

(2)    The current deferred revenue accounted for under Accounting Standards Codification 842, Leases ("ASC 842") is approximately $46,500 and $25,500 as of September 30, 2025 and December 31, 2024, respectively.

(3)    The long-term deferred revenue accounted for under ASC 842 is approximately $119,500 and $95,000 as of September 30, 2025 and December 31, 2024, respectively.

DATA CENTER LESSOR CONSIDERATIONS

Our Global Data Center Business features storage rental provided to customers at contractually specified rates over a fixed contractual period, which are accounted for in accordance with ASC 842. Storage rental revenue associated with our Global Data Center Business for the three and nine months ended September 30, 2025 and 2024 is as follows:

			THREE MONTHS ENDED SEPTEMBER 30,												NINE MONTHS ENDED SEPTEMBER 30,
			2025						2024						2025						2024
Storage rental revenue			$	201,383					$	150,796					$	562,607					$	438,221

H. STOCK-BASED COMPENSATION

Our stock-based compensation expense includes the cost of stock options, restricted stock units ("RSUs") and performance units ("PUs") (together, the "Employee Stock-Based Awards").

STOCK-BASED COMPENSATION EXPENSE

Stock-based compensation expense for the Employee Stock-Based Awards for the three and nine months ended September 30, 2025 and 2024 is as follows:

			THREE MONTHS ENDED SEPTEMBER 30,												NINE MONTHS ENDED SEPTEMBER 30,
			2025						2024						2025						2024
Stock-based compensation expense			$	32,147					$	29,563					$	118,595					$	73,491

On March 1, 2025, we granted approximately 83,400 stock options, 497,000 RSUs and 435,100 PUs under the 2014 Plan (as defined in Note 2.t. to Notes to Consolidated Financial Statements included in our Annual Report).

On May 29, 2025, our stockholders approved an amendment to the 2014 Plan, which (i) increases the number of shares of common stock authorized for issuance under the 2014 Plan by 4,600,000, from 20,750,000 to 25,350,000, and (ii) extends the termination date of the 2014 Plan from May 12, 2031 to May 29, 2035.

As of September 30, 2025, unrecognized compensation cost related to the unvested portion of our Employee Stock-Based Awards, inclusive of our estimated achievement of the performance metrics, is $106,527.

IRON MOUNTAIN SEPTEMBER 30, 2025 FORM 10-Q 14

Table of Contents

Part I. Financial Information

IRON MOUNTAIN INCORPORATED

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (CONTINUED)

(In thousands, except share and per share data) (Unaudited)

2. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (CONTINUED)

I. ACQUISITION AND INTEGRATION COSTS

Acquisition and integration costs represent operating expenditures directly associated with the closing and integration activities of our business acquisitions that have closed, or are highly probable of closing, and include (i) advisory, legal and professional fees to complete business acquisitions and (ii) costs to integrate acquired businesses into our existing operations, including move, severance and system integration costs (collectively, "Acquisition and Integration Costs").

Acquisition and Integration Costs for the three and nine months ended September 30, 2025 and 2024 are as follows:

			THREE MONTHS ENDED SEPTEMBER 30,												NINE MONTHS ENDED SEPTEMBER 30,
			2025						2024						2025						2024
Acquisition and Integration Costs			$	5,402					$	11,262					$	16,040					$	28,573

J. LOSS (GAIN) ON DISPOSAL/WRITE-DOWN OF PROPERTY, PLANT AND EQUIPMENT, NET

Loss (gain) on disposal/write-down of property, plant and equipment, net for the three and nine months ended September 30, 2025 and 2024 is as follows:

			THREE MONTHS ENDED SEPTEMBER 30,												NINE MONTHS ENDED SEPTEMBER 30,
			2025						2024						2025						2024
Loss (gain) on disposal/write-down of property, plant and equipment, net			$	3,366					$	5,091					$	7,975					$	8,270

K. OTHER (INCOME) EXPENSE, NET

Other (income) expense, net for the three and nine months ended September 30, 2025 and 2024 consists of the following:

			THREE MONTHS ENDED SEPTEMBER 30,												NINE MONTHS ENDED SEPTEMBER 30,
DESCRIPTION			2025						2024						2025						2024
Foreign currency transaction (gains) losses, net(1)			$	(7,203)					$	46,657					$	109,615					$	31,291
Debt extinguishment expense			—						5,417						—						5,417
Other, net(2)			3,217						34,288						(3,236)						42,957
Other (Income) Expense, Net			$	(3,986)					$	86,362					$	106,379					$	79,665

(1)The losses for the nine months ended September 30, 2025 and the three and nine months ended September 30, 2024 primarily consist of the impact of changes in the exchange rate of the British pound sterling and the Euro against the United States dollar on our intercompany balances with and between certain of our subsidiaries.

(2)Other, net for the three and nine months ended September 30, 2024 primarily consists of approximately $29,200 in charges associated with the agreement to purchase the remaining interest in the Web Werks JV (as defined in Note 3 to Notes to Consolidated Financial Statements included in our Annual Report) as well as losses on our equity method investments and the change in value of our deferred purchase obligations.

IRON MOUNTAIN SEPTEMBER 30, 2025 FORM 10-Q 15

Table of Contents

Part I. Financial Information

IRON MOUNTAIN INCORPORATED

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (CONTINUED)

(In thousands, except share and per share data) (Unaudited)

2. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (CONTINUED)

L. INCOME TAXES

We provide for income taxes during interim periods based on our estimate of the effective tax rate for the year. Our effective tax rates for the three and nine months ended September 30, 2025 and 2024 are as follows:

			THREE MONTHS ENDED SEPTEMBER 30,												NINE MONTHS ENDED SEPTEMBER 30,
			2025(1)						2024(3)						2025(2)						2024(3)
Effective Tax Rate			16.1		%				58.3		%				44.7		%				35.2		%

(1)The primary reconciling items between the federal statutory tax rate of 21.0% and our overall effective tax rate for the three months ended September 30, 2025 were the benefits derived from the dividends paid deduction, as well as the differences in the tax rates to which our foreign earnings are subject.

(2)The primary reconciling items between the federal statutory tax rate of 21.0% and our overall effective tax rate for the nine months ended September 30, 2025 were the (i) lack of tax benefits recognized for the foreign exchange losses we recorded in Other expense (income), net, during the period, (ii) lack of tax benefits recognized for the year to date ordinary losses of certain entities, (iii) disallowed interest expenses of certain entities and (iv) differences in the tax rates to which our foreign earnings are subject, partially offset by (v) benefits derived from the dividends paid deduction.

(3)The primary reconciling items between the federal statutory tax rate of 21.0% and our overall effective tax rate for the three and nine months ended September 30, 2024 were the (i) lack of tax benefits recognized for the year to date ordinary losses of certain entities, (ii) benefits derived from the dividends paid deduction and (iii) differences in the tax rates to which our foreign earnings are subject. In addition, we recorded gains and losses in Other expense (income), net during the period, for which there was no tax impact.

On July 4, 2025, President Trump signed into law the reconciliation bill, commonly referred to as the One Big Beautiful Bill Act ("OBBBA"). The OBBBA introduces several changes to U.S. federal income tax law, such as suspending the capitalization and amortization of domestic research and development expenditures and reinstating bonus depreciation. It also modifies the deductions available for global intangible low-taxed income from non-U.S. subsidiaries and changes the limitations on deductible interest. Under the current law, not more than 20% of the value of a REIT’s total assets at the end of any quarter could be represented by securities of one or more taxable REIT subsidiaries; the OBBBA increases this threshold to 25% effective January 1, 2026. The effective dates of the OBBBA provisions range from 2025 through 2027. We do not expect the OBBBA provisions to have a material impact on our consolidated financial statements.

In addition, in connection with the removal of the proposed section 899, "Enforcement of Remedies Against Unfair Foreign Taxes," from the OBBBA, the U.S. Treasury Department reached an agreement with the six other G7 countries (Canada, France, Germany, Italy, Japan and the UK) under which U.S. companies will be excluded from the imposition of any Pillar Two Income Inclusion Rule or Undertaxed Profits Rule taxes. We will continue to monitor the global legislative actions as well as administrative guidance related to Pillar Two for potential impacts, which are not expected to have a material impact on our consolidated financial statements.

IRON MOUNTAIN SEPTEMBER 30, 2025 FORM 10-Q 16

Table of Contents

Part I. Financial Information

IRON MOUNTAIN INCORPORATED

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (CONTINUED)

(In thousands, except share and per share data) (Unaudited)

2. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (CONTINUED)

M. INCOME (LOSS) PER SHARE—BASIC AND DILUTED

The calculations of basic and diluted income (loss) per share for the three and nine months ended September 30, 2025 and 2024 are as follows:

			THREE MONTHS ENDED SEPTEMBER 30,												NINE MONTHS ENDED SEPTEMBER 30,
			2025						2024						2025						2024
Net Income (Loss)			$	86,241					$	(33,665)					$	59,134					$	77,981
Less: Net Income (Loss) Attributable to Noncontrolling Interests			1,951						(45)						3,813						1,757
Net Income (Loss) Attributable to Iron Mountain Incorporated (utilized in numerator of Earnings Per Share calculation)			$	84,290					$	(33,620)					$	55,321					$	76,224
Weighted-average shares—basic			295,771,000						293,603,000						295,214,000						293,229,000
Effect of dilutive potential stock options			1,898,000						—						2,020,000						2,143,000
Effect of dilutive potential RSUs and PUs			312,000						—						394,000						540,000
Weighted-average shares—diluted			297,981,000						293,603,000						297,628,000						295,912,000
Net Income (Loss) Per Share Attributable to Iron Mountain Incorporated:
Basic			$	0.28					$	(0.11)					$	0.19					$	0.26
Diluted			$	0.28					$	(0.11)					$	0.19					$	0.26
Antidilutive stock options, RSUs and PUs excluded from the calculation			102,248						3,083,222						112,101						293,457

3. INVESTMENTS

Our joint venture with AGC Equity Partners (the "Frankfurt JV") is accounted for as an equity method investment and is presented as a component of Other within Other assets, net in our Condensed Consolidated Balance Sheets. The carrying value and equity interest in the unconsolidated Frankfurt JV as of September 30, 2025 and December 31, 2024 are as follows:

			SEPTEMBER 30, 2025												DECEMBER 31, 2024
			CARRYING VALUE						EQUITY INTEREST						CARRYING VALUE						EQUITY INTEREST
Frankfurt JV			$	86,093					20		%				$	61,075					20		%

4. DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES

Derivative instruments we are party to include: (i) interest rate swap agreements (which are designated as cash flow hedges) and (ii) cross-currency swap agreements (which are designated as net investment hedges).

INTEREST RATE SWAP AGREEMENTS DESIGNATED AS CASH FLOW HEDGES

We utilize interest rate swap agreements designated as cash flow hedges to limit our exposure to changes in interest rates on a portion of our floating rate indebtedness. Certain of our interest rate swap agreements have notional amounts that will increase with the underlying hedged transaction. Under our interest rate swap agreements, we receive variable rate interest payments associated with the notional amount of each interest rate swap, based upon the one-month Secured Overnight Financing Rate ("SOFR"), in exchange for the payment of fixed interest rates as specified in the interest rate swap agreements. Our interest rate swap agreements are marked to market at the end of each reporting period, representing the fair values of the interest rate swap agreements, and any changes in fair value are recognized as a component of Accumulated other comprehensive items, net. Unrealized gains are recognized as assets, while unrealized losses are recognized as liabilities.

IRON MOUNTAIN SEPTEMBER 30, 2025 FORM 10-Q 17

Table of Contents

Part I. Financial Information

IRON MOUNTAIN INCORPORATED

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (CONTINUED)

(In thousands, except share and per share data) (Unaudited)

4. DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES (CONTINUED)

As of September 30, 2025 and December 31, 2024, we have approximately $1,787,000 and $1,482,000, respectively, in notional value outstanding on our interest rate swap agreements. As of September 30, 2025, our interest rate swap agreements have maturity dates ranging from October 2025 through May 2027.

CROSS-CURRENCY SWAP AGREEMENTS DESIGNATED AS NET INVESTMENT HEDGES

We utilize cross-currency swaps to hedge the variability of exchange rate impacts between the United States dollar and certain of our foreign functional currencies, including the Euro and the Canadian dollar. As of September 30, 2025, our cross-currency swap agreements have maturity dates ranging from February 2026 through November 2026.

The notional values of our cross-currency swaps, by hedged currency, as of September 30, 2025 and December 31, 2024, are as follows:

			SEPTEMBER 30, 2025						DECEMBER 31, 2024
Euro			$	509,187					$	509,187
Canadian dollar			350,000						350,000
			$	859,187					$	859,187

We have designated these cross-currency swap agreements as hedges of net investments in our Euro and Canadian dollar denominated subsidiaries, and they require an exchange of the notional amounts at maturity. These cross-currency swap agreements are marked to market at the end of each reporting period, representing the fair values of the cross-currency swap agreements, and any changes in fair value are recognized as a component of Accumulated other comprehensive items, net. Unrealized gains are recognized as assets, while unrealized losses are recognized as liabilities. The excluded component of our cross-currency swap agreements is recorded in Accumulated other comprehensive items, net and amortized to interest expense on a straight-line basis.

The fair values of derivative instruments recognized in our Condensed Consolidated Balance Sheets as of September 30, 2025 and December 31, 2024, by derivative instrument, are as follows:

			SEPTEMBER 30, 2025												DECEMBER 31, 2024
DERIVATIVE INSTRUMENTS(1)			ASSETS						LIABILITIES						ASSETS						LIABILITIES
Cash Flow Hedges(2)
Interest rate swap agreements			$	243					$	(11,772)					$	1,887					$	(5,326)
Net Investment Hedges(3)
Cross-currency swap agreements			—						(56,458)						26,205						—

(1)Our derivative assets are included as a component of (i) Prepaid expenses and other or (ii) Other within Other assets, net and our derivative liabilities are included as a component of (i) Accrued expenses and other current liabilities or (ii) Other long-term liabilities in our Condensed Consolidated Balance Sheets. As of September 30, 2025, $243 is included within Prepaid expenses and other, $55,681 is included within Accrued expenses and other current liabilities and $12,549 is included within Other long-term liabilities. As of December 31, 2024, $8,891 is included within Prepaid expenses and other, $19,201 is included within Other assets, and $5,326 is included within Other long-term liabilities.

(2)As of September 30, 2025, cumulative net losses recorded within Accumulated other comprehensive items, net associated with our interest rate swap agreements are $9,913.

(3)As of September 30, 2025, cumulative net gains recorded within Accumulated other comprehensive items, net associated with our cross-currency swap agreements are $2,973, which includes cumulative net gains of $59,431 related to the excluded component of our cross-currency swap agreements.

IRON MOUNTAIN SEPTEMBER 30, 2025 FORM 10-Q 18

Table of Contents

Part I. Financial Information

IRON MOUNTAIN INCORPORATED

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (CONTINUED)

(In thousands, except share and per share data) (Unaudited)

4. DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES (CONTINUED)

Unrealized (losses) gains recognized in Accumulated other comprehensive items, net during the three and nine months ended September 30, 2025 and 2024, by derivative instrument, are as follows:

			THREE MONTHS ENDED SEPTEMBER 30,												NINE MONTHS ENDED SEPTEMBER 30,
DERIVATIVE INSTRUMENTS			2025						2024						2025						2024
Cash Flow Hedges
Interest rate swap agreements			$	(72)					$	(34,281)					$	(8,090)					$	(23,381)
Net Investment Hedges
Cross-currency swap agreements			8,416						(18,480)						(82,663)						(7,033)
Cross-currency swap agreements (excluded component)			4,176						4,176						12,529						12,529

(Losses) gains recognized in Net income (loss) during the three and nine months ended September 30, 2025 and 2024, by derivative instrument, are as follows:

			LOCATION OF (LOSS) GAIN			THREE MONTHS ENDED SEPTEMBER 30,												NINE MONTHS ENDED SEPTEMBER 30,
DERIVATIVE INSTRUMENTS						2025						2024						2025						2024
Cash Flow Hedges
Interest rate swap agreements			Interest expense			$	—					$	—					$	—					$	2,528
Net Investment Hedges
Cross-currency swap agreements (excluded component)			Interest expense			(4,176)						(4,176)						(12,529)						(12,529)

IRON MOUNTAIN SEPTEMBER 30, 2025 FORM 10-Q 19

Table of Contents

Part I. Financial Information

IRON MOUNTAIN INCORPORATED

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (CONTINUED)

(In thousands, except share and per share data) (Unaudited)

5. DEBT

Long-term debt is as follows:

						SEPTEMBER 30, 2025																											DECEMBER 31, 2024
						DEBT (INCLUSIVE OF DISCOUNT)						UNAMORTIZED DEFERRED FINANCING COSTS						CARRYING AMOUNT						FAIR VALUE									DEBT (INCLUSIVE OF DISCOUNT)						UNAMORTIZED DEFERRED FINANCING COSTS						CARRYING AMOUNT						FAIR VALUE
Revolving Credit Facility(1)						$	233,000					$	(8,691)					$	224,309					$	233,000								$	121,000					$	(9,253)					$	111,747					$	121,000
Term Loan A(1)						493,750						—						493,750						493,750									216,016						—						216,016						216,016
Term Loan B(1)						1,827,457						(12,864)						1,814,593						1,836,678									1,840,181						(14,690)						1,825,491						1,850,698
Virginia 3 Term Loans(2)						271,079						(1,634)						269,445						271,079									271,079						(3,013)						268,066						271,079
Virginia 4/5 Term Loans(2)						204,987						(277)						204,710						204,987									76,535						(2,752)						73,783						76,535
Virginia 6 Term Loans(2)						210,000						(3,126)						206,874						210,000									137,495						(4,605)						132,890						137,495
Virginia 7 Term Loans(2)						239,595						(5,167)						234,428						239,595									32,074						(7,591)						24,483						32,074
Australian Dollar Term Loan(2)						260,778						(1,989)						258,789						262,606									175,813						(265)						175,548						176,655
UK Revolving Credit Facility						188,186						(2,458)						185,728						188,186									175,503						(1,034)						174,469						175,503
GBP Notes(2)						537,674						(85)						537,589						534,986									501,437						(789)						500,648						490,155
47/8% Notes due 2027(2)(3)						1,000,000						(2,844)						997,156						995,000									1,000,000						(3,910)						996,090						972,500
51/4% Notes due 2028(2)(3)						825,000						(2,952)						822,048						821,906									825,000						(3,838)						821,162						804,375
5% Notes due 2028(2)(3)						500,000						(2,050)						497,950						496,250									500,000						(2,592)						497,408						481,250
7% Notes due 2029(2)(3)						1,000,000						(7,091)						992,909						1,028,750									1,000,000						(8,686)						991,314						1,020,000
47/8% Notes due 2029(2)(3)						1,000,000						(5,786)						994,214						983,750									1,000,000						(6,871)						993,129						945,000
51/4% Notes due 2030(2)(3)						1,300,000						(7,270)						1,292,730						1,283,750									1,300,000						(8,399)						1,291,601						1,235,000
41/2% Notes(2)(3)						1,100,000						(6,741)						1,093,259						1,050,500									1,100,000						(7,674)						1,092,326						1,001,000
5% Notes due 2032(2)						750,000						(8,921)						741,079						720,938									750,000						(9,900)						740,100						688,125
55/8% Notes(2)(3)						600,000						(3,969)						596,031						596,250									600,000						(4,404)						595,596						570,000
61/4% Notes(2)(3)						1,200,000						(13,202)						1,186,798						1,222,500									1,200,000						(14,517)						1,185,483						1,194,000
43/4% Euro Senior Notes due 2034 (the "Euro Notes")(3)(4)						1,408,423						(17,205)						1,391,218						1,410,184									—						—						—						—
Real Estate Mortgages, Financing Lease Liabilities and Other						760,040						(1,624)						758,416						760,040									614,231						(1,825)						612,406						614,231
Accounts Receivable Securitization Program						400,000						(467)						399,533						400,000									400,000						(670)						399,330						400,000
Total Long-term Debt						16,309,969						(116,413)						16,193,556															13,836,364						(117,278)						13,719,086
Less Current Portion						(699,320)						—						(699,320)															(715,109)						—						(715,109)
Long-term Debt, Net of Current Portion						$	15,610,649					$	(116,413)					$	15,494,236														$	13,121,255					$	(117,278)					$	13,003,977

(1)Collectively, the "Credit Agreement". The Credit Agreement consists of a revolving credit facility (the "Revolving Credit Facility"), a term loan A facility (the "Term Loan A") and a term loan B facility (the "Term Loan B"). The remaining amount available for borrowing under the Revolving Credit Facility as of September 30, 2025 was $2,504,559 (which represents the maximum availability as of such date). The weighted average interest rate in effect under the Revolving Credit Facility was 6.0% as of September 30, 2025.

(2)Each as defined in Note 7 to Notes to Consolidated Financial Statements included in our Annual Report.

(3)Collectively, the "Parent Notes". Iron Mountain Incorporated ("IMI") is the direct obligor on the Parent Notes, which are fully and unconditionally guaranteed, on a senior basis, by the Note Guarantors. These guarantees are joint and several obligations of the Note Guarantors. The remainder of our subsidiaries do not guarantee the Parent Notes.

(4)The fair value (Level 2 of the fair value hierarchy described in Note 2.p. to Notes to Consolidated Financial Statements included in our Annual Report) of this debt instrument is based on a quoted market price for comparable notes on September 30, 2025.

IRON MOUNTAIN SEPTEMBER 30, 2025 FORM 10-Q 20

Table of Contents

Part I. Financial Information

IRON MOUNTAIN INCORPORATED

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (CONTINUED)

(In thousands, except share and per share data) (Unaudited)    

5. DEBT (CONTINUED)

See Note 7 to Notes to Consolidated Financial Statements included in our Annual Report for additional information regarding our long-term debt, including the direct obligors of each of our debt instruments as well as information regarding the fair value of our debt instruments (including the levels of the fair value hierarchy used to determine the fair value of our debt instruments, which are consistent with the levels of the fair value hierarchy used to determine the fair value of our debt as of September 30, 2025).

CREDIT AGREEMENT

On June 18, 2025, we amended the Credit Agreement, which resulted in an increase in the principal amount of the Term Loan A from $218,750 to $500,000. Quarterly principal payments of approximately $6,250 on the Term Loan A commenced in September 2025. All other material terms remain the same as disclosed in Note 7 to Notes to Consolidated Financial Statements included in our Annual Report.

AUSTRALIAN DOLLAR TERM LOAN

On June 25, 2025, Iron Mountain Australia Group Pty, Ltd., a wholly owned subsidiary of IMI, amended its AUD Term Loan, which resulted in:

•an extension of the maturity date from September 30, 2026 to September 30, 2030,

•an increase in the original principal amount from 350,000 Australian dollars to 400,000 Australian dollars and

•a decrease in the interest rate from BBSY (an Australian benchmark variable interest rate) plus 3.625% to BBSY plus 3.500%.

The amended loan was issued at 99.5% of par. Principal payments on the AUD Term Loan are to be paid in quarterly installments in an aggregate amount of 10,000 Australian dollars per year, with the remaining balance due September 2030. As of September 30, 2025, we had 397,500 Australian dollars (or $262,606, based upon the exchange rate between the United States dollar and the Australian dollar as of September 30, 2025) outstanding on the AUD Term Loan and the interest rate in effect under the AUD Term Loan was 7.2%. All other material terms of the AUD Term Loan remain the same as disclosed in Note 7 to Notes to Consolidated Financial Statements included in our Annual Report. OUTSTANDING BORROWINGS AU$397,500 7.2% Interest Rate As of September 30, 2025

UK REVOLVING CREDIT FACILITY

Iron Mountain (UK) PLC and Iron Mountain (UK) Data Centre Limited, wholly owned subsidiaries of IMI (collectively, the "UK Borrowers"), have a British pounds sterling Revolving Credit Facility (the "UK Revolving Credit Facility"). The maximum amount permitted to be borrowed under the UK Revolving Credit Facility is 140,000 British pounds sterling, which was fully drawn as of September 30, 2025. We have the option to request additional commitments of up to 125,000 British pounds sterling, subject to conditions specified in the UK Revolving Credit Facility. On July 11, 2025, the UK Borrowers amended the UK Revolving Credit Facility to extend the maturity date from September 24, 2026 to September 24, 2028. As of September 30, 2025, the interest rate in effect under the UK Revolving Credit Facility was 6.1%. All other material terms of the UK Revolving Credit Facility remain consistent with what was disclosed in Note 7 to Notes to Consolidated Financial Statements included in our Annual Report. MAXIMUM AMOUNT £140,000 OPTIONAL ADDITIONAL COMMITMENTS £125,000 6.1% Interest Rate As of September 30, 2025

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Part I. Financial Information

IRON MOUNTAIN INCORPORATED

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (CONTINUED)

(In thousands, except share and per share data) (Unaudited)    

5. DEBT (CONTINUED)

SEPTEMBER 2025 OFFERING

On September 10, 2025, IMI completed a private offering of:

SERIES OF NOTES

AGGREGATE PRINCIPAL AMOUNT

MATURITY DATE

INTEREST PAYMENT DUE

PAR CALL DATE(1)

Euro Notes

€

1,200,000

January 15, 2034

January 15 and July 15

September 10, 2028

(1)We may redeem the Euro Notes at any time, at our option, in whole or in part. Prior to the par call date, we may redeem the Euro Notes at the redemption price or make-whole premium specified in the indenture governing the Euro Notes, together with accrued and unpaid interest to, but excluding, the redemption date. On or after the par call date, we may redeem the Euro Notes at a price equal to 100% of the principal amount being redeemed, together with accrued and unpaid interest to, but excluding, the redemption date.

The Euro Notes were issued at par and have a contractual interest rate of 4.75%. The total net proceeds from the issuance, after deducting the initial purchasers' commissions, of approximately 1,188,000 Euros (or $1,390,651, based upon the exchange rate between the Euro and the United States dollar on September 10, 2025 (the settlement date for the Euro Notes)), were used to repay a portion of the outstanding borrowings under the Revolving Credit Facility and will be used to repay the GBP Notes in the fourth quarter of 2025. As of September 30, 2025, we had 1,200,000 Euros (or $1,408,423, based upon the exchange rate between the United States dollar and the Euro as of September 30, 2025) outstanding on the Euro Notes.

LETTERS OF CREDIT

As of September 30, 2025, we have outstanding letters of credit totaling $75,835, of which $12,441 reduce our borrowing capacity under the Revolving Credit Facility. The letters of credit expire at various dates between October 2025 and May 2027.

DEBT COVENANTS

The Credit Agreement, our bond indentures and other agreements governing our indebtedness contain certain restrictive financial and operating covenants, including covenants that restrict our ability to complete acquisitions, pay cash dividends, incur indebtedness, make investments, sell assets and take other specified corporate actions. The covenants do not contain a rating trigger. Therefore, a change in our debt rating would not trigger a default under the Credit Agreement, our bond indentures or other agreements governing our indebtedness. The Credit Agreement requires that we satisfy a net total lease adjusted leverage ratio and a fixed charge coverage ratio on a quarterly basis, and our bond indentures require that, among other things, we satisfy a leverage ratio (not lease adjusted) or a fixed charge coverage ratio (not lease adjusted) as a condition to taking actions such as paying dividends and incurring indebtedness.

The Credit Agreement uses earnings before interest, taxes, depreciation and amortization and rent expense ("EBITDAR")-based calculations and the bond indentures use earnings before interest, taxes, depreciation and amortization ("EBITDA")-based calculations as the primary measures of financial performance for purposes of calculating leverage and fixed charge coverage ratios. The EBITDAR- and EBITDA-based leverage calculations include our consolidated subsidiaries, other than those we have designated as "Unrestricted Subsidiaries" as defined in the Credit Agreement and bond indentures. Generally, the Credit Agreement and the bond indentures use a trailing four fiscal quarter basis for purposes of the relevant calculations and require certain adjustments and exclusions for purposes of those calculations, which make the calculation of financial performance for purposes of those calculations under the Credit Agreement and bond indentures not directly comparable to Adjusted EBITDA as presented herein. We are in compliance with our leverage and fixed charge coverage ratios under the Credit Agreement, our bond indentures and other agreements governing our indebtedness as of September 30, 2025. Noncompliance with these leverage and fixed charge coverage ratios would have a material adverse effect on our financial condition and liquidity.

6. COMMITMENTS AND CONTINGENCIES

We are involved in litigation from time to time in the ordinary course of business, including litigation arising from damage to customer assets in our facilities caused by fires and other natural disasters. While the outcome of litigation is inherently uncertain, we do not believe any current litigation will have a material adverse effect on our consolidated financial condition, results of operations or cash flows.

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Part I. Financial Information

IRON MOUNTAIN INCORPORATED

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (CONTINUED)

(In thousands, except share and per share data) (Unaudited)

7. STOCKHOLDERS' EQUITY MATTERS

DIVIDENDS

In fiscal year 2024 and the nine months ended September 30, 2025, our board of directors declared the following dividends:

DECLARATION DATE

DIVIDEND PER SHARE

RECORD DATE

TOTAL AMOUNT

PAYMENT DATE

February 22, 2024

$

0.6500

March 15, 2024

$

190,506

April 4, 2024

May 2, 2024

0.6500

June 17, 2024

190,643

July 5, 2024

August 1, 2024

0.7150

September 16, 2024

209,776

October 3, 2024

November 6, 2024

0.7150

December 16, 2024

209,913

January 7, 2025

February 13, 2025

0.7850

March 17, 2025

231,549

April 4, 2025

May 1, 2025

0.7850

June 16, 2025

231,789

July 3, 2025

August 6, 2025

0.7850

September 15, 2025

231,972

October 3, 2025

On November 5, 2025, we declared a dividend to our stockholders of record as of December 15, 2025 of $0.864 per share, payable on January 6, 2026.

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Part I. Financial Information

IRON MOUNTAIN INCORPORATED

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (CONTINUED)

(In thousands, except share and per share data) (Unaudited)

8. SEGMENT INFORMATION

Our Chief Operating Decision Maker ("CODM"), our President and CEO, uses Adjusted EBITDA as the basis for evaluating the performance of, and allocating resources to, our operating segments. The CODM uses Adjusted EBITDA to ensure that resources, including capital, are allocated strategically to support our strategy.

Our reportable segments as of December 31, 2024 are described in Note 11 to Notes to Consolidated Financial Statements included in our Annual Report. Our reportable segments are as follows:

•Global RIM Business

•Global Data Center Business

The remaining activities of our business consist primarily of our Fine Arts and asset lifecycle management ("ALM") businesses and other corporate items ("Corporate and Other").

The operations associated with acquisitions completed during the first nine months of 2025 have been incorporated into our Global RIM Business and Corporate and Other.

An analysis of our business segment information and reconciliation to the accompanying Condensed Consolidated Financial Statements for the three and nine months ended September 30, 2025 and 2024 is as follows:

			GLOBAL RIM BUSINESS						GLOBAL DATA CENTER BUSINESS						TOTAL REPORTABLE SEGMENTS						CORPORATE  AND OTHER						TOTAL CONSOLIDATED
For the Three Months Ended September 30, 2025
Total Revenues			$	1,338,800					$	204,130					$	1,542,930					$	211,163					$	1,754,093
Storage Rental			814,118						201,383						1,015,501						17,396						1,032,897
Service			524,682						2,747						527,429						193,767						721,196
Other Segment Items(1)			740,333						96,753						837,086
Adjusted EBITDA			598,467						107,377						705,844
For the Three Months Ended September 30, 2024
Total Revenues			$	1,260,358					$	153,206					$	1,413,564					$	143,794					$	1,557,358
Storage Rental			767,780						150,796						918,576						17,125						935,701
Service			492,578						2,410						494,988						126,669						621,657
Other Segment Items(1)			691,364						86,410						777,774
Adjusted EBITDA			568,994						66,796						635,790
As of and for the Nine Months Ended September 30, 2025
Total Revenues			$	3,918,540					$	566,728					$	4,485,268					$	573,302					$	5,058,570
Storage Rental			2,375,206						562,607						2,937,813						53,449						2,991,262
Service			1,543,334						4,121						1,547,455						519,853						2,067,308
Other Segments Items(1)			2,177,456						272,269						2,449,725
Adjusted EBITDA			1,741,084						294,459						2,035,543
Total Assets(2)			10,752,581						7,602,266						18,354,847						2,278,006						20,632,853
As of and for the Nine Months Ended September 30, 2024
Total Revenues			$	3,721,092					$	449,845					$	4,170,937					$	397,693					$	4,568,630
Storage Rental			2,253,122						438,221						2,691,343						48,946						2,740,289
Service			1,467,970						11,624						1,479,594						348,747						1,828,341
Other Segment Items(1)			2,077,088						255,464						2,332,552
Adjusted EBITDA			1,644,004						194,381						1,838,385
Total Assets(2)			10,628,084						5,659,583						16,287,667						2,181,962						18,469,629

(1)Relates to Cost of sales (excluding depreciation and amortization) and Selling, general and administrative expenses for the respective reportable segment. The CODM does not regularly review disaggregated expense information included within "Other Segment Items" for any individual segments but may review consolidated Cost of sales (excluding depreciation and amortization) and consolidated Selling, general and administrative expense information to manage the business.

(2)Excludes all intercompany receivables or payables and investment in subsidiary balances.

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Part I. Financial Information

IRON MOUNTAIN INCORPORATED

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (CONTINUED)

(In thousands, except share and per share data) (Unaudited)

8. SEGMENT INFORMATION (CONTINUED)

A reconciliation of Adjusted EBITDA for our reportable segments to total Net Income (Loss) Before Provision (Benefit) for Income Taxes for the three and nine months ended September 30, 2025 and 2024 is as follows:

			THREE MONTHS ENDED SEPTEMBER 30,												NINE MONTHS ENDED SEPTEMBER 30,
			2025						2024						2025						2024
Total Adjusted EBITDA for Reportable Segments			$	705,844					$	635,790					$	2,035,543					$	1,838,385
Add/(Deduct):
Corporate and other			(45,465)						(67,677)						(166,870)						(207,056)
Interest expense, net			(209,740)						(186,067)						(609,541)						(527,107)
Depreciation and amortization			(262,203)						(232,240)						(746,923)						(666,296)
Acquisition and Integration Costs			(5,402)						(11,262)						(16,040)						(28,573)
Restructuring and other transformation			(47,346)						(37,282)						(152,432)						(124,562)
(Loss) gain on disposal/write-down of property, plant and equipment, net (including real estate)			(3,366)						(5,091)						(7,975)						(8,270)
Other income (expense), net, excluding our share of (losses) gains from our unconsolidated joint ventures			5,329						(85,532)						(102,751)						(76,954)
Stock-based compensation expense			(32,147)						(29,563)						(118,595)						(73,491)
Our share of Adjusted EBITDA reconciling items from our unconsolidated joint ventures			(2,669)						(2,341)						(7,557)						(5,767)
Total Net Income (Loss) Before Provision (Benefit) for Income Taxes			$	102,835					$	(21,265)					$	106,859					$	120,309

IRON MOUNTAIN SEPTEMBER 30, 2025 FORM 10-Q 25

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Part I. Financial Information

IRON MOUNTAIN INCORPORATED

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (CONTINUED)

(In thousands, except share and per share data) (Unaudited)

8. SEGMENT INFORMATION (CONTINUED)

Segment revenue by product and service lines for the three and nine months ended September 30, 2025 and 2024 is as follows:

			THREE MONTHS ENDED SEPTEMBER 30,												NINE MONTHS ENDED SEPTEMBER 30,
			2025						2024						2025						2024
Global RIM Business
Records Management(1)			$	1,060,359					$	990,333					$	3,107,681					$	2,901,465
Data Management(1)			134,339						127,583						380,372						390,706
Information Destruction(1)(2)			144,102						142,442						430,487						428,921
Data Center(1)			—						—						—						—
Global Data Center Business
Records Management(1)			$	—					$	—					$	—					$	—
Data Management(1)			—						—						—						—
Information Destruction(1)			—						—						—						—
Data Center(1)			204,130						153,206						566,728						449,845
Corporate and Other
Records Management(1)			$	42,340					$	41,460					$	130,813					$	121,528
Data Management(1)			—						—						—						—
Information Destruction(1)(3)			168,823						102,334						442,489						276,165
Data Center(1)			—						—						—						—
Total Consolidated
Records Management(1)			$	1,102,699					$	1,031,793					$	3,238,494					$	3,022,993
Data Management(1)			134,339						127,583						380,372						390,706
Information Destruction(1)(2)(3)			312,925						244,776						872,976						705,086
Data Center(1)			204,130						153,206						566,728						449,845

(1)Each of these offerings has a component of revenue that is storage rental related and a component that is service related, except for information destruction, which does not have a storage rental component.

(2)Information destruction revenue for our Global RIM Business includes secure shredding services.

(3)Information destruction revenue for Corporate and Other includes product revenue from our ALM business.

9. RELATED PARTIES

We have agreements with the Frankfurt JV whereby we earn various fees, including (i) special project revenue and (ii) property management and construction and development fees for services we are providing to the Frankfurt JV (the "Frankfurt JV Agreements").

Revenue recognized in the accompanying Condensed Consolidated Statements of Operations under these agreements for the three and nine months ended September 30, 2025 and 2024 is as follows (approximately):

			THREE MONTHS ENDED SEPTEMBER 30,												NINE MONTHS ENDED SEPTEMBER 30,
			2025						2024						2025						2024
Frankfurt JV Agreements(1)			$	—					$	200					$	—					$	2,700

(1)Revenue associated with the Frankfurt JV Agreements is presented as a component of our Global Data Center Business segment.

IRON MOUNTAIN SEPTEMBER 30, 2025 FORM 10-Q 26

Table of Contents

Part I. Financial Information

IRON MOUNTAIN INCORPORATED

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (CONTINUED)

(In thousands, except share and per share data) (Unaudited)

10. RESTRUCTURING AND OTHER TRANSFORMATION

PROJECT MATTERHORN

In September 2022, we announced Project Matterhorn. Project Matterhorn investments focus on transforming our operating model to a global operating model. Project Matterhorn focuses on the formation of a solution-based sales approach that is designed to allow us to optimize our shared services and best practices to better serve our customers' needs. We are investing to accelerate growth and to capture a greater share of the large, global addressable markets in which we operate. We expect Project Matterhorn to be completed by December 31, 2025. We have incurred approximately $530,900 in Restructuring and other transformation costs from the inception of Project Matterhorn through September 30, 2025. Costs are comprised of (1) restructuring costs, which include (i) site consolidation and other related exit costs, (ii) employee severance costs and (iii) certain professional fees associated with these activities, and (2) other transformation costs, which include professional fees such as project management costs and costs for third party consultants who are assisting in the enablement of our growth initiatives.

Restructuring and other transformation related to Project Matterhorn included in the accompanying Condensed Consolidated Statements of Operations for the three and nine months ended September 30, 2025 and 2024, and from the inception of Project Matterhorn through September 30, 2025, is as follows:

			THREE MONTHS ENDED SEPTEMBER 30,												NINE MONTHS ENDED SEPTEMBER 30,												FROM INCEPTION THROUGH SEPTEMBER 30, 2025
			2025						2024						2025						2024
Restructuring			$	21,502					$	11,556					$	61,604					$	38,618					$	183,297
Other transformation			25,844						25,726						90,828						85,944						347,642
Restructuring and other transformation			$	47,346					$	37,282					$	152,432					$	124,562					$	530,939

Restructuring costs for Project Matterhorn, included as a component of Restructuring and other transformation in the accompanying Condensed Consolidated Statements of Operations, by segment, for the three and nine months ended September 30, 2025 and 2024, and from the inception of Project Matterhorn through September 30, 2025, are as follows:

			THREE MONTHS ENDED SEPTEMBER 30,												NINE MONTHS ENDED SEPTEMBER 30,												FROM INCEPTION THROUGH SEPTEMBER 30, 2025
			2025						2024						2025						2024
Global RIM Business			$	18,827					$	10,731					$	56,227					$	33,515					$	158,162
Global Data Center Business			220						—						371						2,576						3,947
Corporate and Other			2,455						825						5,006						2,527						21,188
Total restructuring costs			$	21,502					$	11,556					$	61,604					$	38,618					$	183,297

Other transformation costs for Project Matterhorn, included as a component of Restructuring and other transformation in the accompanying Condensed Consolidated Statements of Operations, by segment, for the three and nine months ended September 30, 2025 and 2024, and from the inception of Project Matterhorn through September 30, 2025, are as follows:

			THREE MONTHS ENDED SEPTEMBER 30,												NINE MONTHS ENDED SEPTEMBER 30,												FROM INCEPTION THROUGH SEPTEMBER 30, 2025
			2025						2024						2025						2024
Global RIM Business			$	10,008					$	10,799					$	32,719					$	30,143					$	103,326
Global Data Center Business			2,299						1,292						4,811						3,955						14,631
Corporate and Other			13,537						13,635						53,298						51,846						229,685
Total other transformation costs			$	25,844					$	25,726					$	90,828					$	85,944					$	347,642

IRON MOUNTAIN SEPTEMBER 30, 2025 FORM 10-Q 27

Table of Contents

Part I. Financial Information

IRON MOUNTAIN INCORPORATED

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (CONTINUED)

(In thousands, except share and per share data) (Unaudited)

10. RESTRUCTURING AND OTHER TRANSFORMATION (CONTINUED)

The rollforward of the accrued restructuring costs and accrued other transformation costs, which are included as components of Accrued expenses and other current liabilities in our Condensed Consolidated Balance Sheets, for December 31, 2024 through September 30, 2025, is as follows:

			RESTRUCTURING						OTHER TRANSFORMATION						TOTAL RESTRUCTURING AND OTHER TRANSFORMATION
Balance as of December 31, 2024			$	6,974					$	13,004					$	19,978
Amount accrued			61,604						90,828						152,432
Payments			(54,027)						(87,597)						(141,624)
Balance as of September 30, 2025			$	14,551					$	16,235					$	30,786

IRON MOUNTAIN SEPTEMBER 30, 2025 FORM 10-Q 28

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Part I. Financial Information

ITEM 2. MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

The following discussion and analysis of our financial condition and results of operations for the three and nine months ended September 30, 2025 should be read in conjunction with our Condensed Consolidated Financial Statements and Notes thereto for the three and nine months ended September 30, 2025, included herein, and our Consolidated Financial Statements and Notes thereto for the year ended December 31, 2024, included in our Annual Report on Form 10-K filed with the United States Securities and Exchange Commission ("SEC") on February 14, 2025 (our "Annual Report").

FORWARD-LOOKING STATEMENTS

We have made statements in this Quarterly Report that constitute "forward-looking statements" as that term is defined in the Private Securities Litigation Reform Act of 1995 and other securities laws. These forward-looking statements concern our current expectations regarding our future results from operations, economic performance, financial condition, goals, strategies, investment objectives, plans and achievements. These forward-looking statements are subject to various known and unknown risks, uncertainties and other factors, and you should not rely upon them except as statements of our present intentions and of our present expectations, which may or may not occur. When we use words such as "believes", "expects", "anticipates", "estimates", "plans", "intends", "pursue", "commits", "will" or similar expressions, we are making forward-looking statements. Although we believe that our forward-looking statements are based on reasonable assumptions, our expected results may not be achieved, and actual results may differ materially from our expectations. In addition, important factors that could cause actual results to differ from expectations include, among others:

•our ability or inability to execute our strategic growth plan, including our ability to invest according to plan, grow our businesses (including through joint ventures or other co-investment vehicles), incorporate alternative technologies (including artificial intelligence) into our offerings, achieve satisfactory returns on new product offerings, continue our revenue management, expand and manage our global operations, complete acquisitions on satisfactory terms, integrate acquired companies efficiently and transition to more sustainable sources of energy;

•changes in customer preferences and demand for our storage and information management services, including as a result of the shift from paper and tape storage to alternative technologies that require less physical space or services activity;

•the costs of complying with and our ability to comply with laws, regulations and customer requirements, including those relating to data privacy and cybersecurity issues, as well as fire and safety and environmental standards;

•the impact of attacks on our internal information technology ("IT") systems, including the impact of such incidents on our reputation and ability to compete and any litigation or disputes that may arise in connection with such incidents;

•our ability to fund capital expenditures;

•the impact of our distribution requirements on our ability to execute our business plan;

•our ability to remain qualified for taxation as a real estate investment trust for United States federal income tax purposes ("REIT");

•changes in the political and economic environments in the countries in which we operate and changes in the global political climate;

•our ability to raise debt or equity capital and changes in the cost of our debt;

•our ability to comply with our existing debt obligations and restrictions in our debt instruments;

•the impact of service interruptions or equipment damage and the cost of power on our data center operations;

•the cost or potential liabilities associated with real estate necessary for our business;

•unexpected events, including those resulting from climate change or geopolitical events, could disrupt our operations and adversely affect our reputation and results of operations;

•failures to implement and manage new IT systems;

•other trends in competitive or economic conditions affecting our financial condition or results of operations not presently contemplated; and

•the other risks described in our periodic reports filed with the SEC, including under the caption "Risk Factors" in Part I, Item 1A of our Annual Report.

Except as required by law, we undertake no obligation to update any forward-looking statements appearing in this report.

IRON MOUNTAIN SEPTEMBER 30, 2025 FORM 10-Q 29

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Part I. Financial Information

OVERVIEW

The following discussions set forth, for the periods indicated, management's discussion and analysis of financial condition and results of operations. Significant trends and changes are discussed for the three and nine months ended September 30, 2025 within each section. Trends and changes that are consistent for both the three and nine month periods are not repeated and are discussed on a year to date basis only.

PROJECT MATTERHORN

In September 2022, we announced a global program designed to accelerate the growth of our business ("Project Matterhorn"). Project Matterhorn investments focus on transforming our operating model to a global operating model. Project Matterhorn focuses on the formation of a solution-based sales approach that is designed to allow us to optimize our shared services and best practices to better serve our customers' needs. We are investing to accelerate growth and to capture a greater share of the large, global addressable markets in which we operate. We expect Project Matterhorn to be completed by December 31, 2025. We have incurred approximately $530.9 million in Restructuring and other transformation costs from the inception of Project Matterhorn through September 30, 2025. Costs are comprised of (1) restructuring costs, which include (i) site consolidation and other related exit costs, (ii) employee severance costs and (iii) certain professional fees associated with these activities, and (2) other transformation costs, which include professional fees such as project management costs and costs for third party consultants who are assisting in the enablement of our growth initiatives.

See Note 10 to Notes to Condensed Consolidated Financial Statements included in this Quarterly Report for more information on Restructuring and other transformation costs.

GENERAL

RESULTS OF OPERATIONS—KEY TRENDS

•Our organic storage rental revenue growth is primarily driven by revenue management in our Global RIM Business segment, where we expect volume to be relatively stable in the near term, as well as by growth in our Global Data Center Business segment, primarily driven by lease commencements.

•Our organic service revenue growth is primarily due to increases in our service activity. We expect organic service revenue growth for the remainder of 2025 and into 2026 to benefit from our new and existing digital offerings and asset lifecycle management ("ALM") business, as well as our traditional services.

•We expect continued total revenue and Adjusted EBITDA (as defined below) growth for the remainder of 2025 and into 2026 as a result of our focus on new product and service offerings, innovation, customer solutions and market expansion in line with our Project Matterhorn objectives and growth strategies.

Cost of sales (excluding depreciation and amortization) and Selling, general and administrative expenses for the nine months ended September 30, 2025 consists of the following:

COST OF SALES						SELLING, GENERAL AND ADMINISTRATIVE EXPENSES

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Part I. Financial Information

NON-GAAP MEASURES

ADJUSTED EBITDA

We define Adjusted EBITDA as net income (loss) before interest expense, net, provision (benefit) for income taxes, depreciation and amortization (inclusive of our share of Adjusted EBITDA from our unconsolidated joint ventures), and excluding certain items we do not believe to be indicative of our core operating results, specifically:

EXCLUDED
•Acquisition and Integration Costs (as defined below) •Restructuring and other transformation •Loss (gain) on disposal/write-down of property, plant and equipment, net (including real estate)						•Other (income) expense, net •Stock-based compensation expense •Intangible impairments

Adjusted EBITDA Margin is calculated by dividing Adjusted EBITDA by total revenues. We also show Adjusted EBITDA and Adjusted EBITDA Margin for each of our reportable segments under "Results of Operations—Segment Analysis" below.

Adjusted EBITDA excludes both interest expense, net and the provision (benefit) for income taxes. These expenses are associated with our capitalization and tax structures, which we do not consider when evaluating the operating profitability of our core operations. Adjusted EBITDA does not include depreciation and amortization expenses, in order to eliminate the impact of capital investments, which we evaluate by comparing capital expenditures to incremental revenue generated and as a percentage of total revenues. Adjusted EBITDA and Adjusted EBITDA Margin should be considered in addition to, but not as a substitute for, other measures of financial performance reported in accordance with accounting principles generally accepted in the United States of America ("GAAP"), such as operating income (loss), net income (loss) or cash flows from operating activities.

RECONCILIATION OF NET INCOME (LOSS) TO ADJUSTED EBITDA (IN THOUSANDS):

			THREE MONTHS ENDED SEPTEMBER 30,												NINE MONTHS ENDED SEPTEMBER 30,
			2025						2024						2025						2024
Net Income (Loss)			$	86,241					$	(33,665)					$	59,134					$	77,981
Add/(Deduct):
Interest expense, net			209,740						186,067						609,541						527,107
Provision (benefit) for income taxes			16,594						12,400						47,725						42,328
Depreciation and amortization			262,203						232,240						746,923						666,296
Acquisition and Integration Costs(1)			5,402						11,262						16,040						28,573
Restructuring and other transformation			47,346						37,282						152,432						124,562
Loss (gain) on disposal/write-down of property, plant and equipment, net (including real estate)			3,366						5,091						7,975						8,270
Other (income) expense, net, excluding our share of losses (gains) from our unconsolidated joint ventures			(5,329)						85,532						102,751						76,954
Stock-based compensation expense			32,147						29,563						118,595						73,491
Our share of Adjusted EBITDA reconciling items from our unconsolidated joint ventures			2,669						2,341						7,557						5,767
Adjusted EBITDA			$	660,379					$	568,113					$	1,868,673					$	1,631,329

(1)Represents operating expenditures directly associated with the closing and integration activities of our business acquisitions that have closed, or are highly probable of closing, and include (i) advisory, legal and professional fees to complete business acquisitions and (ii) costs to integrate acquired businesses into our existing operations, including move, severance and system integration costs (collectively, "Acquisition and Integration Costs").

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Part I. Financial Information

ADJUSTED EPS

We define Adjusted EPS as reported earnings per share fully diluted from net income (loss) attributable to Iron Mountain Incorporated (inclusive of our share of adjusted losses (gains) from our unconsolidated joint ventures) and excluding certain items, specifically:

EXCLUDED
•Acquisition and Integration Costs •Restructuring and other transformation •Loss (gain) on disposal/write-down of property, plant and equipment, net (including real estate) •Other (income) expense, net						•Stock-based compensation expense •Non-cash amortization related to derivative instruments •Tax impact of reconciling items and discrete tax items •Amortization related to the write-off of certain customer relationship intangible assets

We do not believe these excluded items to be indicative of our ongoing operating results, and they are not considered when we are forecasting our future results. We believe Adjusted EPS is of value to our current and potential investors when comparing our results from past, present and future periods.

RECONCILIATION OF REPORTED EPS—FULLY DILUTED FROM NET INCOME (LOSS) ATTRIBUTABLE TO IRON MOUNTAIN INCORPORATED TO ADJUSTED EPS—FULLY DILUTED FROM NET INCOME (LOSS) ATTRIBUTABLE TO IRON MOUNTAIN INCORPORATED:

			THREE MONTHS ENDED SEPTEMBER 30,												NINE MONTHS ENDED SEPTEMBER 30,
			2025						2024						2025						2024
Reported EPS—Fully Diluted from Net Income (Loss) Attributable to Iron Mountain Incorporated			$	0.28					$	(0.11)					$	0.19					$	0.26
Add/(Deduct):
Acquisition and Integration Costs			0.02						0.04						0.05						0.10
Restructuring and other transformation			0.16						0.13						0.51						0.42
Loss (gain) on disposal/write-down of property, plant and equipment, net (including real estate)			0.01						0.02						0.03						0.03
Other (income) expense, net, excluding our share of losses (gains) from our unconsolidated joint ventures			(0.02)						0.29						0.35						0.26
Stock-based compensation expense			0.11						0.10						0.40						0.25
Non-cash amortization related to derivative instruments			0.01						0.01						0.04						0.04
Tax impact of reconciling items and discrete tax items(1)			(0.04)						(0.04)						(0.10)						(0.08)
Income (Loss) Attributable to Noncontrolling Interests			0.01						—						0.01						0.01
Adjusted EPS—Fully Diluted from Net Income (Loss) Attributable to Iron Mountain Incorporated(2)			$	0.54					$	0.44					$	1.48					$	1.28

(1)The differences between our effective tax rates and our structural tax rate (or adjusted effective tax rates) for the three and nine months ended September 30, 2025 and 2024 are primarily due to (i) the reconciling items above, which impact our reported net income (loss) before provision (benefit) for income taxes but have an insignificant impact on our reported provision (benefit) for income taxes and (ii) other discrete tax items. Our structural tax rate for purposes of the calculation of Adjusted EPS for the three and nine months ended September 30, 2025 and 2024 was 14.8% and 15.1%, respectively. The tax impact of reconciling items and discrete tax items is calculated using the current quarter's estimate of the annual structural tax rate. This may result in the current period adjustment plus prior period reported quarterly adjustments not summing to the full year adjustment.

(2)Columns may not foot due to rounding.

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Part I. Financial Information

FFO (NAREIT) AND FFO (NORMALIZED)

Funds from operations ("FFO") is defined by the National Association of Real Estate Investment Trusts as net income (loss) excluding depreciation on real estate assets, losses and gains on sale of real estate, net of tax, and amortization of data center leased-based intangibles ("FFO (Nareit)"). We calculate our FFO measures, including FFO (Nareit), adjusting for our share of reconciling items from our unconsolidated joint ventures. FFO (Nareit) does not give effect to real estate depreciation because these amounts are computed, under GAAP, to allocate the cost of a property over its useful life. Because values for well-maintained real estate assets have historically increased or decreased based upon prevailing market conditions, we believe that FFO (Nareit) provides investors with a clearer view of our operating performance. Our most directly comparable GAAP measure to FFO (Nareit) is net income (loss).

We modify FFO (Nareit), as is common among REITs seeking to provide financial measures that most meaningfully reflect their particular business ("FFO (Normalized)"). Our definition of FFO (Normalized) excludes certain items included in FFO (Nareit) that we believe are not indicative of our core operating results, specifically:

EXCLUDED
•Acquisition and Integration Costs •Restructuring and other transformation •Loss (gain) on disposal/write-down of property, plant and equipment, net (excluding real estate) •Other (income) expense, net •Stock-based compensation expense						•Non-cash amortization related to derivative instruments •Real estate financing lease depreciation •Tax impact of reconciling items and discrete tax items •Intangible impairments •(Income) loss from discontinued operations, net of tax

RECONCILIATION OF NET INCOME (LOSS) TO FFO (NAREIT) AND FFO (NORMALIZED) (IN THOUSANDS):

			THREE MONTHS ENDED SEPTEMBER 30,												NINE MONTHS ENDED SEPTEMBER 30,
			2025						2024						2025						2024
Net Income (Loss)			$	86,241					$	(33,665)					$	59,134					$	77,981
Add/(Deduct):
Real estate depreciation			108,405						93,864						309,738						275,208
Loss (gain) on sale of real estate, net of tax			194						531						(4,475)						(84)
Data center lease-based intangible assets amortization			1,858						5,604						5,560						16,751
Our share of FFO (Nareit) reconciling items from our unconsolidated joint ventures			1,612						1,422						4,675						2,975
FFO (Nareit)			198,310						67,756						374,632						372,831
Add/(Deduct):
Acquisition and Integration Costs			5,402						11,262						16,040						28,573
Restructuring and other transformation			47,346						37,282						152,432						124,562
Loss (gain) on disposal/write-down of property, plant and equipment, net (excluding real estate)			3,168						4,554						12,269						8,583
Other (income) expense, net, excluding our share of losses (gains) from our unconsolidated joint ventures(1)			(5,329)						85,532						102,751						76,954
Stock-based compensation expense			32,147						29,563						118,595						73,491
Non-cash amortization related to derivative instruments			4,176						4,176						12,529						12,529
Real estate financing lease depreciation			3,276						3,692						9,850						9,914
Tax impact of reconciling items and discrete tax items(2)			(11,547)						(10,465)						(28,719)						(24,992)
Our share of FFO (Normalized) reconciling items from our unconsolidated joint ventures			(58)						(83)						(241)						(92)
FFO (Normalized)			$	276,891					$	233,269					$	770,138					$	682,353

(1)Includes foreign currency transaction losses (gains), net and other, net. See Note 2.k. to Notes to Condensed Consolidated Financial Statements included in this Quarterly Report for additional information regarding the components of Other (income) expense, net.

(2)Represents the tax impact of (i) the reconciling items above, which impact our reported net income (loss) before provision (benefit) for income taxes but have an insignificant impact on our reported provision (benefit) for income taxes and (ii) other discrete tax items. Discrete tax items resulted in a provision (benefit) for income taxes of ($1.6 million) and $1.0 million for the three and nine months ended September 30, 2025, respectively, and $0.4 million and ($0.1 million) for the three and nine months ended September 30, 2024, respectively.

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Part I. Financial Information

CRITICAL ACCOUNTING ESTIMATES

Our discussion and analysis of our financial condition and results of operations are based upon our Condensed Consolidated Financial Statements, which have been prepared in accordance with GAAP. The preparation of these financial statements requires us to make estimates, judgments and assumptions that affect the reported amounts of assets, liabilities, revenues and expenses, and related disclosure of contingent assets and liabilities at the date of the financial statements and for the period then ended. On an ongoing basis, we evaluate the estimates used. We base our estimates on historical experience, actuarial estimates, current conditions and various other assumptions that we believe to be reasonable under the circumstances. These estimates form the basis for making judgments about the carrying values of assets and liabilities and are not readily apparent from other sources. Actual results may differ from these estimates. Our critical accounting estimates include the following, which are listed in no particular order:

•Revenue Recognition

•Accounting for Acquisitions

•Impairment of Tangible and Intangible Assets

•Income Taxes

Further detail regarding our critical accounting estimates can be found in "Item 7. Management's Discussion and Analysis of Financial Condition and Results of Operations" in our Annual Report, and the Consolidated Financial Statements and the Notes included therein. We have determined that no material changes concerning our critical accounting estimates have occurred since December 31, 2024.

RESULTS OF OPERATIONS

COMPARISON OF THE THREE AND NINE MONTHS ENDED SEPTEMBER 30, 2025 TO THE THREE AND NINE MONTHS ENDED SEPTEMBER 30, 2024 (IN THOUSANDS):

			THREE MONTHS ENDED SEPTEMBER 30,												DOLLAR CHANGE						PERCENTAGE CHANGE
			2025						2024
Revenues			$	1,754,093					$	1,557,358					$	196,735					12.6		%
Operating Expenses			1,445,504						1,306,194						139,310						10.7		%
Operating Income			308,589						251,164						57,425						22.9		%
Other Expenses, Net			222,348						284,829						(62,481)						(21.9)		%
Net Income (Loss)			86,241						(33,665)						119,906						356.2		%
Net Income (Loss) Attributable to Noncontrolling Interests			1,951						(45)						1,996						4,435.6		%
Net Income (Loss) Attributable to Iron Mountain Incorporated			$	84,290					$	(33,620)					$	117,910					350.7		%
Adjusted EBITDA(1)			$	660,379					$	568,113					$	92,266					16.2		%
Adjusted EBITDA Margin(1)			37.6		%				36.5		%
			NINE MONTHS ENDED SEPTEMBER 30,												DOLLAR CHANGE						PERCENTAGE CHANGE
			2025						2024
Revenues			$	5,058,570					$	4,568,630					$	489,940					10.7		%
Operating Expenses			4,235,791						3,841,549						394,242						10.3		%
Operating Income			822,779						727,081						95,698						13.2		%
Other Expenses, Net			763,645						649,100						114,545						17.6		%
Net Income (Loss)			59,134						77,981						(18,847)						(24.2)		%
Net Income (Loss) Attributable to Noncontrolling Interests			3,813						1,757						2,056						117.0		%
Net Income (Loss) Attributable to Iron Mountain Incorporated			$	55,321					$	76,224					$	(20,903)					(27.4)		%
Adjusted EBITDA(1)			$	1,868,673					$	1,631,329					$	237,344					14.5		%
Adjusted EBITDA Margin(1)			36.9		%				35.7		%

(1)See "Non-GAAP Measures—Adjusted EBITDA" in this Quarterly Report for the definitions of Adjusted EBITDA and Adjusted EBITDA Margin, reconciliation of Net Income (Loss) to Adjusted EBITDA and a discussion of why we believe these non-GAAP measures provide relevant and useful information to our current and potential investors.

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Part I. Financial Information

REVENUES

Total revenues consist of the following (in thousands):

			THREE MONTHS ENDED SEPTEMBER 30,																		PERCENTAGE CHANGE
			2025						2024						DOLLAR CHANGE						ACTUAL						CONSTANT CURRENCY(1)						ORGANIC GROWTH(2)						IMPACT OF ACQUISITIONS
Storage Rental			$	1,032,897					$	935,701					$	97,196					10.4		%				9.5		%				9.4		%				0.1		%
Service			721,196						621,657						99,539						16.0		%				15.3		%				9.8		%				5.5		%
Total Revenues			$	1,754,093					$	1,557,358					$	196,735					12.6		%				11.8		%				9.6		%				2.2		%
			NINE MONTHS ENDED SEPTEMBER 30,																		PERCENTAGE CHANGE
			2025						2024						DOLLAR CHANGE						ACTUAL						CONSTANT CURRENCY(1)						ORGANIC GROWTH(2)						IMPACT OF ACQUISITIONS
Storage Rental			$	2,991,262					$	2,740,289					$	250,973					9.2		%				9.2		%				9.1		%				0.1		%
Service			2,067,308						1,828,341						238,967						13.1		%				13.2		%				8.9		%				4.3		%
Total Revenues			$	5,058,570					$	4,568,630					$	489,940					10.7		%				10.8		%				9.0		%				1.8		%

(1)Constant currency growth rate, which is a non-GAAP measure, is calculated by translating the 2024 results at the 2025 average exchange rates.

(2)Our organic revenue growth rate, which is a non-GAAP measure, represents the year-over-year growth rate of our revenues excluding the impact of business acquisitions, divestitures and foreign currency exchange rate fluctuations. Our organic revenue growth rate includes the impact of acquisitions of customer relationships.

TOTAL REVENUES

Primary factors influencing the change in reported storage rental revenue and reported service revenue for the nine months ended September 30, 2025 compared to the nine months ended September 30, 2024 include the following:

STORAGE RENTAL REVENUE						•organic storage rental revenue growth driven by revenue management in our Global RIM Business segment and lease commencements and improved pricing in our Global Data Center Business segment.
SERVICE REVENUE						•organic service revenue growth driven by increases in Global Digital Solutions and traditional service activity levels in our Global RIM Business segment and increased volume in our ALM business; and •an increase of $73.0 million due to recent acquisitions in our ALM business.

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Part I. Financial Information

OPERATING EXPENSES

COST OF SALES

Cost of sales (excluding depreciation and amortization) consists of the following expenses (in thousands):

			THREE MONTHS ENDED SEPTEMBER 30,																		PERCENTAGE CHANGE												% OF TOTAL REVENUES												PERCENTAGE CHANGE (FAVORABLE)/ UNFAVORABLE
			2025						2024						DOLLAR CHANGE						ACTUAL						CONSTANT CURRENCY						2025						2024
Labor			$	302,986					$	264,499					$	38,487					14.6		%				13.4		%				17.3		%				17.0		%				0.3		%
Facilities			298,811						279,043						19,768						7.1		%				6.0		%				17.0		%				17.9		%				(0.9)		%
Transportation			41,473						44,236						(2,763)						(6.2)		%				(7.1)		%				2.4		%				2.8		%				(0.4)		%
Product Cost of Sales and Other			148,669						90,612						58,057						64.1		%				63.6		%				8.5		%				5.8		%				2.7		%
Total Cost of sales			$	791,939					$	678,390					$	113,549					16.7		%				15.7		%				45.1		%				43.6		%				1.5		%
			NINE MONTHS ENDED SEPTEMBER 30,																		PERCENTAGE CHANGE												% OF TOTAL REVENUES												PERCENTAGE CHANGE (FAVORABLE)/ UNFAVORABLE
			2025						2024						DOLLAR CHANGE						ACTUAL						CONSTANT CURRENCY						2025						2024
Labor			$	869,311					$	779,998					$	89,313					11.5		%				11.4		%				17.2		%				17.1		%				0.1		%
Facilities			879,751						832,187						47,564						5.7		%				5.5		%				17.4		%				18.2		%				(0.8)		%
Transportation			130,548						134,539						(3,991)						(3.0)		%				(3.1)		%				2.6		%				2.9		%				(0.3)		%
Product Cost of Sales and Other			377,370						260,892						116,478						44.6		%				44.7		%				7.5		%				5.7		%				1.8		%
Total Cost of sales			$	2,256,980					$	2,007,616					$	249,364					12.4		%				12.3		%				44.6		%				43.9		%				0.7		%

Primary factors influencing the change in reported Cost of sales for the nine months ended September 30, 2025 compared to the nine months ended September 30, 2024 include the following:

•an increase in labor costs driven by an increase in service activity, primarily within our Global RIM Business segment and ALM business, including the impact of recent acquisitions;

•an increase in facilities expenses, primarily driven by higher real estate taxes in our Global Data Center Business segment, and increases in utilities and rent expense; and

•an increase in product cost of sales and other in our ALM business as a result of higher product volumes.

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Part I. Financial Information

SELLING, GENERAL AND ADMINISTRATIVE EXPENSES

Selling, general and administrative expenses consists of the following expenses (in thousands):

			THREE MONTHS ENDED SEPTEMBER 30,																		PERCENTAGE CHANGE												% OF TOTAL REVENUES												PERCENTAGE CHANGE (FAVORABLE)/ UNFAVORABLE
			2025						2024						DOLLAR CHANGE						ACTUAL						CONSTANT CURRENCY						2025						2024
General, Administrative and Other			$	237,505					$	252,463					$	(14,958)					(5.9)		%				(6.2)		%				13.5		%				16.2		%				(2.7)		%
Sales, Marketing and Account Management			97,743						89,466						8,277						9.3		%				8.2		%				5.6		%				5.7		%				(0.1)		%
Total Selling, general and administrative expenses			$	335,248					$	341,929					$	(6,681)					(2.0)		%				(2.4)		%				19.1		%				22.0		%				(2.9)		%
			NINE MONTHS ENDED SEPTEMBER 30,																		PERCENTAGE CHANGE												% OF TOTAL REVENUES												PERCENTAGE CHANGE (FAVORABLE)/ UNFAVORABLE
			2025						2024						DOLLAR CHANGE						ACTUAL						CONSTANT CURRENCY						2025						2024
General, Administrative and Other			$	767,430					$	738,075					$	29,355					4.0		%				4.1		%				15.2		%				16.2		%				(1.0)		%
Sales, Marketing and Account Management			288,011						268,157						19,854						7.4		%				7.3		%				5.7		%				5.9		%				(0.2)		%
Total Selling, general and administrative expenses			$	1,055,441					$	1,006,232					$	49,209					4.9		%				5.0		%				20.9		%				22.0		%				(1.1)		%

Primary factors influencing the change in reported Selling, general and administrative expenses for the nine months ended September 30, 2025 compared to the nine months ended September 30, 2024 include the following:

•an increase in general, administrative and other expenses, primarily driven by higher compensation expense; and

•an increase in sales, marketing and account management expenses, primarily driven by higher compensation expense and increased marketing costs.

The decrease in General, Administrative and Other for the three months ended September 30, 2025 compared to the three months ended September 30, 2024 is primarily driven by lower compensation expense and professional fees.

DEPRECIATION AND AMORTIZATION

Depreciation expense increased by $65.6 million, or 14.0%, for the nine months ended September 30, 2025 compared to the prior year period. See Note 2.i. to Notes to Consolidated Financial Statements included in our Annual Report for additional information regarding the useful lives over which our property, plant and equipment is depreciated.

Amortization expense increased by $15.1 million, or 7.6%, for the nine months ended September 30, 2025 compared to the prior year period.

ACQUISITION AND INTEGRATION COSTS

Acquisition and Integration Costs for the nine months ended September 30, 2025 and 2024 were approximately $16.0 million and $28.6 million, respectively.

RESTRUCTURING AND OTHER TRANSFORMATION

Restructuring and other transformation costs for the nine months ended September 30, 2025 and 2024 were $152.4 million and $124.6 million, respectively, and related to operating expenses associated with the implementation of Project Matterhorn.

LOSS (GAIN) ON DISPOSAL/WRITE-DOWN OF PROPERTY, PLANT AND EQUIPMENT, NET

Loss (gain) on disposal/write-down of property, plant and equipment, net for the nine months ended September 30, 2025 and 2024 was approximately $8.0 million and $8.3 million, respectively.

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Part I. Financial Information

OTHER EXPENSES, NET

INTEREST EXPENSE, NET

Interest expense, net increased by $82.4 million to $609.5 million in the nine months ended September 30, 2025 from $527.1 million in the prior year period. The increase is primarily due to higher average debt outstanding during the nine months ended September 30, 2025 compared to the prior year period. Our weighted average interest rate, inclusive of the fees associated with our outstanding letters of credit, was 5.6% and 5.7% at September 30, 2025 and 2024, respectively. See Note 5 to Notes to Condensed Consolidated Financial Statements included in this Quarterly Report for additional information regarding our indebtedness.

OTHER (INCOME) EXPENSE, NET

Other (income) expense, net for the three and nine months ended September 30, 2025 and 2024 consists of the following (in thousands):

			THREE MONTHS ENDED SEPTEMBER 30,												DOLLAR CHANGE						NINE MONTHS ENDED SEPTEMBER 30,												DOLLAR CHANGE
DESCRIPTION			2025						2024												2025						2024
Foreign currency transaction (gains) losses, net(1)			$	(7,203)					$	46,657					$	(53,860)					$	109,615					$	31,291					$	78,324
Debt extinguishment expense			—						5,417						(5,417)						—						5,417						(5,417)
Other, net			3,217						34,288						(31,071)						(3,236)						42,957						(46,193)
Other (Income) Expense, Net			$	(3,986)					$	86,362					$	(90,348)					$	106,379					$	79,665					$	26,714

(1)The losses for the nine months ended September 30, 2025 primarily consist of the impact of changes in the exchange rate of the British pound sterling and the Euro against the United States dollar on our intercompany balances with and between certain of our subsidiaries.

PROVISION FOR INCOME TAXES

We provide for income taxes during interim periods based on our estimate of the effective tax rate for the year. Our effective tax rates for the three and nine months ended September 30, 2025 and 2024 are as follows:

			THREE MONTHS ENDED SEPTEMBER 30,												NINE MONTHS ENDED SEPTEMBER 30,
			2025						2024						2025						2024
Effective Tax Rate			16.1		%				58.3		%				44.7		%				35.2		%

The primary reconciling items between the federal statutory tax rate of 21.0% and our overall effective tax rate for the three months ended September 30, 2025 were the benefits derived from the dividends paid deduction, as well as the differences in the tax rates to which our foreign earnings are subject. The primary reconciling items between the federal statutory tax rate of 21.0% and our overall effective tax rate for the nine months ended September 30, 2025 were the (i) lack of tax benefits recognized for the foreign exchange losses we recorded in Other expense (income), net, during the period, (ii) lack of tax benefits recognized for the year to date ordinary losses of certain entities, (iii) disallowed interest expenses of certain entities and (iv) differences in the tax rates to which our foreign earnings are subject, partially offset by (v) benefits derived from the dividends paid deduction.

On July 4, 2025, President Trump signed into law the reconciliation bill, commonly referred to as the One Big Beautiful Bill Act ("OBBBA"). The OBBBA introduces several changes to U.S. federal income tax law, such as suspending the capitalization and amortization of domestic research and development expenditures and reinstating bonus depreciation. It also modifies the deductions available for global intangible low-taxed income from non-U.S. subsidiaries and changes the limitations on deductible interest. Under the current law, not more than 20% of the value of a REIT’s total assets at the end of any quarter could be represented by securities of one or more taxable REIT subsidiaries; the OBBBA increases this threshold to 25% effective January 1, 2026. The effective dates of the OBBBA provisions range from 2025 through 2027. We do not expect the OBBBA provisions to have a material impact on our consolidated financial statements.

In addition, in connection with the removal of the proposed section 899, "Enforcement of Remedies Against Unfair Foreign Taxes," from the OBBBA, the U.S. Treasury Department reached an agreement with the six other G7 countries (Canada, France, Germany, Italy, Japan and the UK) under which U.S. companies will be excluded from the imposition of any Pillar Two Income Inclusion Rule or Undertaxed Profits Rule taxes. We will continue to monitor the global legislative actions as well as administrative guidance related to Pillar Two for potential impacts, which are not expected to have a material impact on our consolidated financial statements.

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Part I. Financial Information

NET INCOME (LOSS) AND ADJUSTED EBITDA

The following table reflects the effect of the foregoing factors on our net income (loss) and Adjusted EBITDA (in thousands):

			THREE MONTHS ENDED SEPTEMBER 30,												DOLLAR CHANGE						PERCENTAGE CHANGE
			2025						2024
Net Income (Loss)			$	86,241					$	(33,665)					$	119,906					356.2		%
Net Income (Loss) as a percentage of Revenue			4.9		%				(2.2)		%
Adjusted EBITDA			$	660,379					$	568,113					$	92,266					16.2		%
Adjusted EBITDA Margin			37.6		%				36.5		%
			NINE MONTHS ENDED SEPTEMBER 30,												DOLLAR CHANGE						PERCENTAGE CHANGE
			2025						2024
Net Income (Loss)			$	59,134					$	77,981					$	(18,847)					(24.2)		%
Net Income (Loss) as a percentage of Revenue			1.2		%				1.7		%
Adjusted EBITDA			$	1,868,673					$	1,631,329					$	237,344					14.5		%
Adjusted EBITDA Margin			36.9		%				35.7		%

Adjusted EBITDA Margin for the nine months ended September 30, 2025 increased 120 basis points from the same prior year period driven by favorable overhead management, offset by changes in our revenue mix. ↑ INCREASED BY $237.3 MILLION OR 14.5% Adjusted EBITDA

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Part I. Financial Information

SEGMENT ANALYSIS

See Note 8 to Notes to Condensed Consolidated Financial Statements included in this Quarterly Report for a description of our reportable segments.

GLOBAL RIM BUSINESS (IN THOUSANDS)

			THREE MONTHS ENDED SEPTEMBER 30,																		PERCENTAGE CHANGE
															DOLLAR CHANGE						ACTUAL						CONSTANT CURRENCY						ORGANIC GROWTH						IMPACT OF ACQUISITIONS
			2025						2024
Storage Rental			$	814,118					$	767,780					$	46,338					6.0		%				5.3		%				5.1		%				0.2		%
Service			524,682						492,578						32,104						6.5		%				5.8		%				4.7		%				1.1		%
Segment Revenue			$	1,338,800					$	1,260,358					$	78,442					6.2		%				5.5		%				5.0		%				0.5		%
Segment Adjusted EBITDA			$	598,467					$	568,994					$	29,473
Segment Adjusted EBITDA Margin			44.7		%				45.1		%
			NINE MONTHS ENDED SEPTEMBER 30,																		PERCENTAGE CHANGE
															DOLLAR CHANGE						ACTUAL						CONSTANT CURRENCY						ORGANIC GROWTH						IMPACT OF ACQUISITIONS
			2025						2024
Storage Rental			$	2,375,206					$	2,253,122					$	122,084					5.4		%				5.6		%				5.5		%				0.1		%
Service			1,543,334						1,467,970						75,364						5.1		%				5.3		%				4.9		%				0.4		%
Segment Revenue			$	3,918,540					$	3,721,092					$	197,448					5.3		%				5.5		%				5.3		%				0.2		%
Segment Adjusted EBITDA			$	1,741,084					$	1,644,004					$	97,080
Segment Adjusted EBITDA Margin			44.4		%				44.2		%

NINE MONTHS ENDED YEAR OVER YEAR SEGMENT ANALYSIS: GLOBAL RIM BUSINESS (IN MILLIONS)

Storage Rental
Revenue Service
Revenue Segment
Revenue Segment Adjusted
EBITDA

Primary factors influencing the change in revenue and Adjusted EBITDA Margin in our Global RIM Business segment for the nine months ended September 30, 2025 compared to the prior year period include the following:

•organic storage rental revenue growth driven by revenue management;

•organic service revenue growth primarily driven by increases in our Global Digital Solutions business and growth in our traditional service activity levels; and

•a 20 basis point increase in Adjusted EBITDA Margin primarily driven by ongoing cost containment measures and revenue management.

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Part I. Financial Information

GLOBAL DATA CENTER BUSINESS (IN THOUSANDS)

			THREE MONTHS ENDED SEPTEMBER 30,																		PERCENTAGE CHANGE
															DOLLAR CHANGE						ACTUAL						CONSTANT CURRENCY						ORGANIC GROWTH						IMPACT OF ACQUISITIONS
			2025						2024
Storage Rental			$	201,383					$	150,796					$	50,587					33.5		%				32.1		%				32.1		%				—		%
Service			2,747						2,410						337						14.0		%				10.9		%				10.9		%				—		%
Segment Revenue			$	204,130					$	153,206					$	50,924					33.2		%				31.7		%				31.7		%				—		%
Segment Adjusted EBITDA			$	107,377					$	66,796					$	40,581
Segment Adjusted EBITDA Margin			52.6		%				43.6		%
			NINE MONTHS ENDED SEPTEMBER 30,																		PERCENTAGE CHANGE
															DOLLAR CHANGE						ACTUAL						CONSTANT CURRENCY						ORGANIC GROWTH						IMPACT OF ACQUISITIONS
			2025						2024
Storage Rental			$	562,607					$	438,221					$	124,386					28.4		%				27.6		%				27.6		%				—		%
Service			4,121						11,624						(7,503)						(64.5)		%				(65.3)		%				(65.3)		%				—		%
Segment Revenue			$	566,728					$	449,845					$	116,883					26.0		%				25.2		%				25.2		%				—		%
Segment Adjusted EBITDA			$	294,459					$	194,381					$	100,078
Segment Adjusted EBITDA Margin			52.0		%				43.2		%

NINE MONTHS ENDED YEAR OVER YEAR SEGMENT ANALYSIS: GLOBAL DATA CENTER BUSINESS (IN MILLIONS)

Storage Rental
Revenue Service
Revenue Segment
Revenue Segment Adjusted
EBITDA

Primary factors influencing the change in revenue and Adjusted EBITDA Margin in our Global Data Center Business segment for the nine months ended September 30, 2025 compared to the prior year period include the following:

•organic storage rental revenue growth from leases that commenced during the first nine months of 2025 and in prior periods, improved pricing and increased usage of pass-through power;

•increase in Adjusted EBITDA primarily driven by organic storage rental revenue growth; and

•an 880 basis point increase in Adjusted EBITDA Margin reflecting recent lease commencements, improved pricing and cost containment.

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Part I. Financial Information

CORPORATE AND OTHER (IN THOUSANDS)

			THREE MONTHS ENDED SEPTEMBER 30,																		PERCENTAGE CHANGE
															DOLLAR CHANGE						ACTUAL						CONSTANT CURRENCY						ORGANIC GROWTH						IMPACT OF ACQUISITIONS
			2025						2024
Storage Rental			$	17,396					$	17,125					$	271					1.6		%				0.9		%				0.9		%				—		%
Service			193,767						126,669						67,098						53.0		%				52.7		%				29.5		%				23.2		%
Revenue			$	211,163					$	143,794					$	67,369					46.9		%				46.5		%				26.1		%				20.4		%
Adjusted EBITDA			$	(45,465)					$	(67,677)					$	22,212
			NINE MONTHS ENDED SEPTEMBER 30,																		PERCENTAGE CHANGE
															DOLLAR CHANGE						ACTUAL						CONSTANT CURRENCY						ORGANIC GROWTH						IMPACT OF ACQUISITIONS
			2025						2024
Storage Rental			$	53,449					$	48,946					$	4,503					9.2		%				8.6		%				8.6		%				—		%
Service			519,853						348,747						171,106						49.1		%				49.0		%				28.1		%				20.9		%
Revenue			$	573,302					$	397,693					$	175,609					44.2		%				44.0		%				25.7		%				18.3		%
Adjusted EBITDA			$	(166,870)					$	(207,056)					$	40,186

Primary factors influencing the change in revenue and Adjusted EBITDA in Corporate and Other (as defined in Note 8 to Notes to Condensed Consolidated Financial Statements included in this Quarterly Report) for the nine months ended September 30, 2025 compared to the prior year period include the following:

•an increase in service revenue of $73.0 million due to recent acquisitions in our ALM business;

•organic service revenue growth in our ALM business driven by increased volume and improved component pricing trends; and

•an improvement in Adjusted EBITDA driven by service revenue improvement in our ALM business.

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Part I. Financial Information

LIQUIDITY AND CAPITAL RESOURCES

GENERAL

We expect to meet our short-term and long-term cash flow requirements through cash generated from operations, cash on hand, borrowings under the Credit Agreement (as defined below), as well as other potential financings (such as the issuance of debt). Our cash flow requirements, both in the near and long term, include, but are not limited to, capital expenditures, the repayment of outstanding debt, shareholder dividends, potential business acquisitions and normal business operation needs.

PROJECT MATTERHORN

As disclosed above, Project Matterhorn was announced in September 2022 and is expected to be completed by December 31, 2025. We have incurred approximately $530.9 million in Restructuring and other transformation costs from the inception of Project Matterhorn through September 30, 2025. During the nine months ended September 30, 2025 and 2024, we incurred approximately $152.4 million and $124.6 million, respectively, of Restructuring and other transformation costs related to Project Matterhorn, which are comprised of (1) restructuring costs, which include (i) site consolidation and other related exit costs, (ii) employee severance costs and (iii) certain professional fees associated with these activities, and (2) other transformation costs, which include professional fees such as project management costs and costs for third party consultants who are assisting in the enablement of our growth initiatives.

CASH FLOWS

The following is a summary of our cash balances and cash flows (in thousands) as of and for the nine months ended September 30,

			2025						2024
Cash Flows from Operating Activities			$	840,001					$	765,128
Cash Flows from Investing Activities			(1,968,259)						(1,441,829)
Cash Flows from Financing Activities			1,201,195						639,201
Cash and Cash Equivalents, End of Period			195,210						168,515

A. CASH FLOWS FROM OPERATING ACTIVITIES

For the nine months ended September 30, 2025, net cash flows provided by operating activities increased by $74.9 million compared to the prior year period, primarily due to an increase in net income (excluding non-cash charges) of $53.0 million and an increase in cash from working capital of $21.9 million.

B. CASH FLOWS FROM INVESTING ACTIVITIES

Our significant investing activity during the nine months ended September 30, 2025 included cash paid for capital expenditures of $1,755.4 million. Additional details of our capital spending are included in the "Capital Expenditures" section below.

C. CASH FLOWS FROM FINANCING ACTIVITIES

Our significant financing activities during the nine months ended September 30, 2025 included:

•Net proceeds of approximately $1,390.7 million associated with the issuance of the Euro Notes (as defined below).

•Net proceeds of approximately $798.7 million primarily associated with borrowings under our data center credit facilities, which were used to partially finance the construction of our data centers, and the Revolving Credit Facility.

•Payment of dividends in the amount of $687.2 million on our common stock.

•Payment of deferred purchase obligations and other deferred payments of $240.2 million.

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Part I. Financial Information

CAPITAL EXPENDITURES

The following table presents our capital spend for the nine months ended September 30, 2025 and 2024, organized by the type of the spending as described in our Annual Report (in thousands):

			NINE MONTHS ENDED SEPTEMBER 30,
NATURE OF CAPITAL SPEND			2025						2024
Growth Investment Capital Expenditures:
Data Center			$	1,329,821					$	880,239
Real Estate			108,083						130,829
Innovation and Other			104,512						61,352
Total Growth Investment Capital Expenditures			1,542,416						1,072,420
Recurring Capital Expenditures:
Data Center			$	14,455					$	13,242
Real Estate			37,929						39,750
Non-Real Estate			52,097						54,058
Total Recurring Capital Expenditures			104,481						107,050
Total Capital Spend (on accrual basis)			$	1,646,897					$	1,179,470
Net increase (decrease) in prepaid capital expenditures			13,958						1,423
Net decrease (increase) in accrued capital expenditures			94,528						(6,925)
Total Capital Spend (on cash basis)			$	1,755,383					$	1,173,968

    

Excluding capital expenditures associated with potential future acquisitions, we expect total capital expenditures of approximately $1,950.0 million for the year ending December 31, 2025. Of this, we expect capital expenditures for growth investment of approximately $1,800.0 million and recurring capital expenditures of approximately $150.0 million.

DIVIDENDS

See Note 7 to Notes to Condensed Consolidated Financial Statements included in this Quarterly Report for a listing of dividends that we declared during the first nine months of 2025 and fiscal year 2024.

On November 5, 2025, we declared a dividend to our stockholders of record as of December 15, 2025 of $0.864 per share, payable on January 6, 2026.

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Part I. Financial Information

FINANCIAL INSTRUMENTS AND DEBT

Financial instruments that potentially subject us to credit risk consist principally of cash and cash equivalents (including money market funds and time deposits) and accounts receivable. The only significant concentrations of liquid investments as of September 30, 2025 are related to cash and cash equivalents held in money market funds. See Note 2.e. to Notes to Condensed Consolidated Financial Statements included in this Quarterly Report for information on our money market funds and time deposits.

Long-term debt as of September 30, 2025 is as follows (in thousands):

			SEPTEMBER 30, 2025
			DEBT (INCLUSIVE OF DISCOUNT)						UNAMORTIZED DEFERRED FINANCING COSTS						CARRYING AMOUNT
Revolving Credit Facility(1)			$	233,000					$	(8,691)					$	224,309
Term Loan A(1)			493,750						—						493,750
Term Loan B(1)			1,827,457						(12,864)						1,814,593
Virginia 3 Term Loans(2)			271,079						(1,634)						269,445
Virginia 4/5 Term Loans(2)			204,987						(277)						204,710
Virginia 6 Term Loans(2)			210,000						(3,126)						206,874
Virginia 7 Term Loans(2)			239,595						(5,167)						234,428
Australian Dollar Term Loan(2)			260,778						(1,989)						258,789
UK Revolving Credit Facility			188,186						(2,458)						185,728
GBP Notes(2)			537,674						(85)						537,589
47/8% Notes due 2027(2)(3)			1,000,000						(2,844)						997,156
51/4% Notes due 2028(2)(3)			825,000						(2,952)						822,048
5% Notes due 2028(2)(3)			500,000						(2,050)						497,950
7% Notes due 2029(2)(3)			1,000,000						(7,091)						992,909
47/8% Notes due 2029(2)(3)			1,000,000						(5,786)						994,214
51/4% Notes due 2030(2)(3)			1,300,000						(7,270)						1,292,730
41/2% Notes(2)(3)			1,100,000						(6,741)						1,093,259
5% Notes due 2032(2)			750,000						(8,921)						741,079
55/8% Notes(2)(3)			600,000						(3,969)						596,031
61/4% Notes(2)(3)			1,200,000						(13,202)						1,186,798
43/4% Euro Senior Notes due 2034 (the "Euro Notes")(3)			1,408,423						(17,205)						1,391,218
Real Estate Mortgages, Financing Lease Liabilities and Other			760,040						(1,624)						758,416
Accounts Receivable Securitization Program			400,000						(467)						399,533
Total Long-term Debt			16,309,969						(116,413)						16,193,556
Less Current Portion			(699,320)						—						(699,320)
Long-term Debt, Net of Current Portion			$	15,610,649					$	(116,413)					$	15,494,236

(1)Collectively, the "Credit Agreement". The Credit Agreement consists of a revolving credit facility (the "Revolving Credit Facility"), a term loan A facility (the "Term Loan A") and a term loan B facility (the "Term Loan B").

(2)Each as defined in Note 7 to Notes to Consolidated Financial Statements included in our Annual Report.

(3)Collectively, the "Parent Notes".

See Note 7 to Notes to Consolidated Financial Statements included in our Annual Report and Note 5 to Notes to Condensed Consolidated Financial Statements included in this Quarterly Report for additional information regarding our long-term debt.

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Part I. Financial Information

CREDIT AGREEMENT

On June 18, 2025, we amended the Credit Agreement, which resulted in an increase in the principal amount of the Term Loan A from $218.8 million to $500.0 million. Quarterly principal payments of approximately $6.3 million on the Term Loan A commenced in September 2025. All other material terms remain the same as disclosed in Note 7 to Notes to Consolidated Financial Statements included in our Annual Report.

AUSTRALIAN DOLLAR TERM LOAN

On June 25, 2025, Iron Mountain Australia Group Pty, Ltd., a wholly owned subsidiary of Iron Mountain Incorporated ("IMI"), amended its AUD Term Loan, which resulted in:

•an extension of the maturity date from September 30, 2026 to September 30, 2030,

•an increase in the original principal amount from 350.0 million Australian dollars to 400.0 million Australian dollars and

•a decrease in the interest rate from BBSY (an Australian benchmark variable interest rate) plus 3.625% to BBSY plus 3.500%.

The amended loan was issued at 99.5% of par. Principal payments on the AUD Term Loan are to be paid in quarterly installments in an aggregate amount of 10.0 million Australian dollars per year, with the remaining balance due September 2030. As of September 30, 2025, we had 397.5 million Australian dollars (or $262.6 million, based upon the exchange rate between the United States dollar and the Australian dollar as of September 30, 2025) outstanding on the AUD Term Loan and the interest rate in effect under the AUD Term Loan was 7.2%.

All other material terms of the AUD Term Loan remain the same as disclosed in Note 7 to Notes to Consolidated Financial Statements included in our Annual Report.

UK REVOLVING CREDIT FACILITY

Iron Mountain (UK) PLC and Iron Mountain (UK) Data Centre Limited, wholly owned subsidiaries of IMI (collectively, the "UK Borrowers"), have a British pounds sterling Revolving Credit Facility (the "UK Revolving Credit Facility"). The maximum amount permitted to be borrowed under the UK Revolving Credit Facility is 140.0 million British pounds sterling, which was fully drawn as of September 30, 2025. We have the option to request additional commitments of up to 125.0 million British pounds sterling, subject to conditions specified in the UK Revolving Credit Facility.

On July 11, 2025, the UK Borrowers amended the UK Revolving Credit Facility to extend the maturity date from September 24, 2026 to September 24, 2028. As of September 30, 2025, the interest rate in effect under the UK Revolving Credit Facility was 6.1%. All other material terms of the UK Revolving Credit Facility remain the same as disclosed in Note 7 to Notes to Consolidated Financial Statements included in our Annual Report.

SEPTEMBER 2025 OFFERING

On September 10, 2025, IMI completed a private offering of (in thousands):

SERIES OF NOTES

AGGREGATE PRINCIPAL AMOUNT

MATURITY DATE

INTEREST PAYMENT DUE

PAR CALL DATE(1)

Euro Notes

€

1,200,000

January 15, 2034

January 15 and July 15

September 10, 2028

(1)We may redeem the Euro Notes at any time, at our option, in whole or in part. Prior to the par call date, we may redeem the Euro Notes at the redemption price or make-whole premium specified in the indenture governing the Euro Notes, together with accrued and unpaid interest to, but excluding, the redemption date. On or after the par call date, we may redeem the Euro Notes at a price equal to 100% of the principal amount being redeemed, together with accrued and unpaid interest to, but excluding, the redemption date.

The Euro Notes were issued at par and have a contractual interest rate of 4.75%. The total net proceeds from the issuance, after deducting the initial purchasers' commissions, of approximately 1,188.0 million Euros (or $1,390.7 million, based upon the exchange rate between the Euro and the United States dollar on September 10, 2025 (the settlement date for the Euro Notes)), were used to repay a portion of the outstanding borrowings under the Revolving Credit Facility and will be used to repay the GBP Notes in the fourth quarter of 2025. As of September 30, 2025, we had 1,200.0 million Euros (or $1,408.4 million, based upon the exchange rate between the United States dollar and the Euro as of September 30, 2025) outstanding on the Euro Notes.

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Part I. Financial Information

DEBT COVENANTS

The Credit Agreement, our bond indentures and other agreements governing our indebtedness contain certain restrictive financial and operating covenants, including covenants that restrict our ability to complete acquisitions, pay cash dividends, incur indebtedness, make investments, sell assets and take other specified corporate actions. The covenants do not contain a rating trigger. Therefore, a change in our debt rating would not trigger a default under the Credit Agreement, our bond indentures or other agreements governing our indebtedness. The Credit Agreement requires that we satisfy a net total lease adjusted leverage ratio and a fixed charge coverage ratio on a quarterly basis, and our bond indentures require that, among other things, we satisfy a leverage ratio (not lease adjusted) or a fixed charge coverage ratio (not lease adjusted) as a condition to taking actions such as paying dividends and incurring indebtedness.

The Credit Agreement uses earnings before interest, taxes, depreciation and amortization and rent expense ("EBITDAR")-based calculations and the bond indentures use EBITDA-based calculations as the primary measures of financial performance for purposes of calculating leverage and fixed charge coverage ratios. The EBITDAR- and EBITDA-based leverage calculations include our consolidated subsidiaries, other than those we have designated as "Unrestricted Subsidiaries" as defined in the Credit Agreement and bond indentures. Generally, the Credit Agreement and the bond indentures use a trailing four fiscal quarter basis for purposes of the relevant calculations and require certain adjustments and exclusions for purposes of those calculations, which make the calculation of financial performance for purposes of those calculations under the Credit Agreement and bond indentures not directly comparable to Adjusted EBITDA as presented herein. These adjustments can be significant. For example, the calculation of financial performance under the Credit Agreement and certain of our bond indentures includes (subject to specified exceptions and caps) adjustments for non-cash charges and for expected benefits associated with (i) completed acquisitions, (ii) certain executed lease agreements associated with our data center business that have yet to commence, and (iii) restructuring and other strategic initiatives. The calculation of financial performance under our other bond indentures includes, for example, adjustments for non-cash charges and for expected benefits associated with (i) completed acquisitions and (ii) events that are extraordinary, unusual or non-recurring.

Our leverage and fixed charge coverage ratios under the Credit Agreement as of September 30, 2025 are as follows:

SEPTEMBER 30, 2025

MAXIMUM/MINIMUM ALLOWABLE

Net total lease adjusted leverage ratio

5.0

Maximum allowable of 7.0

Fixed charge coverage ratio

2.5

Minimum allowable of 1.5

We are in compliance with our leverage and fixed charge coverage ratios under the Credit Agreement, our bond indentures and other agreements governing our indebtedness as of September 30, 2025. Noncompliance with these leverage and fixed charge coverage ratios would have a material adverse effect on our financial condition and liquidity.

Our ability to pay interest on or to refinance our indebtedness depends on our future performance, working capital levels and capital structure, which are subject to general economic, financial, competitive, legislative, regulatory and other factors which may be beyond our control. There can be no assurance that we will generate sufficient cash flow from our operations or that future financings will be available on acceptable terms or in amounts sufficient to enable us to service or refinance our indebtedness or to make necessary capital expenditures.

DERIVATIVE INSTRUMENTS

INTEREST RATE SWAP AGREEMENTS

We utilize interest rate swap agreements designated as cash flow hedges to limit our exposure to changes in interest rates on a portion of our floating rate indebtedness. Certain of our interest rate swap agreements have notional amounts that will increase with the underlying hedged transaction. Under our interest rate swap agreements, we receive variable rate interest payments associated with the notional amount of each interest rate swap, based upon the one-month Secured Overnight Financing Rate ("SOFR"), in exchange for the payment of fixed interest rates as specified in the interest rate swap agreements. Our interest rate swap agreements are marked to market at the end of each reporting period, representing the fair values of the interest rate swap agreements, and any changes in fair value are recognized as a component of Accumulated other comprehensive items, net. Unrealized gains are recognized as assets, while unrealized losses are recognized as liabilities.

As of September 30, 2025 and December 31, 2024, we have approximately $1,787.0 million and $1,482.0 million, respectively, in notional value outstanding on our interest rate swap agreements. As of September 30, 2025, our interest rate swap agreements have maturity dates ranging from October 2025 through May 2027.

IRON MOUNTAIN SEPTEMBER 30, 2025 FORM 10-Q 47

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Part I. Financial Information

CROSS-CURRENCY SWAP AGREEMENTS

We utilize cross-currency swaps to hedge the variability of exchange rate impacts between the United States dollar and certain of our foreign functional currencies, including the Euro and the Canadian dollar. As of September 30, 2025, our cross-currency swap agreements have maturity dates ranging from February 2026 through November 2026.

The notional values of our cross-currency swaps, by hedged currency, as of September 30, 2025 and December 31, 2024, are as follows (in thousands):

			SEPTEMBER 30, 2025						DECEMBER 31, 2024
Euro			$	509,187					$	509,187
Canadian dollar			350,000						350,000
			$	859,187					$	859,187

We have designated these cross-currency swap agreements as hedges of net investments in our Euro and Canadian dollar denominated subsidiaries, and they require an exchange of the notional amounts at maturity. These cross-currency swap agreements are marked to market at the end of each reporting period, representing the fair values of the cross-currency swap agreements, and any changes in fair value are recognized as a component of Accumulated other comprehensive items, net. Unrealized gains are recognized as assets, while unrealized losses are recognized as liabilities. The excluded component of our cross-currency swap agreements is recorded in Accumulated other comprehensive items, net and amortized to interest expense on a straight-line basis.

INVESTMENTS

Our joint venture with AGC Equity Partners (the "Frankfurt JV") is accounted for as an equity method investment and is presented as a component of Other within Other assets, net in our Condensed Consolidated Balance Sheets. The carrying value and equity interest in the unconsolidated Frankfurt JV as of September 30, 2025 and December 31, 2024 are as follows (in thousands):

			SEPTEMBER 30, 2025												DECEMBER 31, 2024
			CARRYING VALUE						EQUITY INTEREST						CARRYING VALUE						EQUITY INTEREST
Frankfurt JV			$	86,093					20		%				$	61,075					20		%

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Part I. Financial Information

ITEM 4. CONTROLS AND PROCEDURES

DISCLOSURE CONTROLS AND PROCEDURES

The term "disclosure controls and procedures" is defined in Rules 13a-15(e) and 15d-15(e) of the Securities Exchange Act of 1934, as amended (the "Exchange Act"). These rules refer to the controls and other procedures of a company that are designed to ensure that information is recorded, processed, accumulated, summarized, communicated and reported to management, including its principal executive and principal financial officers, as appropriate to allow timely decisions regarding what is required to be disclosed by a company in the reports that it files under the Exchange Act.

As of September 30, 2025 (the "Evaluation Date"), we carried out an evaluation, under the supervision and with the participation of our management, including our chief executive officer and chief financial officer, of the effectiveness of our disclosure controls and procedures. Based upon that evaluation, our chief executive officer and chief financial officer concluded that, as of the Evaluation Date, our disclosure controls and procedures are effective.

CHANGES IN INTERNAL CONTROL OVER FINANCIAL REPORTING

Our management, with the participation of our principal executive officer and principal financial officer, is responsible for establishing and maintaining adequate internal control over financial reporting as defined in Rules 13a-15(f) and 15d-15(f) of the Exchange Act. Our internal control system is designed to provide reasonable assurance to our management and board of directors regarding the preparation and fair presentation of published financial statements.

There were no changes in our internal control over financial reporting that occurred during the quarter ended September 30, 2025 that have materially affected, or are reasonably likely to materially affect, our internal control over financial reporting.

IRON MOUNTAIN SEPTEMBER 30, 2025 FORM 10-Q 49

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Part II. Other Information

PART II. OTHER INFORMATION

ITEM 2. UNREGISTERED SALES OF EQUITY SECURITIES AND USE OF PROCEEDS

We did not sell any unregistered equity securities during the three months ended September 30, 2025, nor did we repurchase any shares of our common stock during the three months ended September 30, 2025.

ITEM 5. OTHER INFORMATION

On September 8, 2025, Ms. Pamela Arway, a member of our board of directors, adopted a 10b5-1 trading plan to sell up to 100% of the net shares to be acquired upon vesting of her 2026 and 2027 annual equity awards between May 7, 2026 and May 26, 2027. Ms. Arway’s plan will terminate on the earlier of June 30, 2027 and the date that all trades under the plan are completed.

This arrangement was entered into during an open trading window and is intended to satisfy the affirmative defense of Rule 10b5-1(c) under the Exchange Act.

ITEM 6. EXHIBITS

(A) EXHIBITS

Certain exhibits indicated below are incorporated by reference to documents we have filed with the SEC.

EXHIBIT NO.						DESCRIPTION
3.1						Certificate of Incorporation of the Company, as filed with the Secretary of State of the State of Delaware on June 26, 2014, as corrected by the Certificate of Correction of the Company filed with the Secretary of State of the State of Delaware on June 30, 2014. (Incorporated by reference to Annex B-1 to the Company’s Proxy Statement for a Special Meeting of Stockholders, filed with the SEC on December 23, 2014.)
3.2						Certificate of Merger, amending the Certificate of Incorporation, effective January 20, 2015. (Incorporated by reference to Exhibit 3.2 to the Company’s Form 8-K filed with the SEC on January 21, 2015.)
3.3						Certificate of Amendment of the Certificate of Incorporation, effective May 31, 2024. (Incorporated by reference to Annex A to the Company's Proxy Statement for an Annual Meeting of Stockholders, filed with the SEC on April 19, 2024.)
3.4						Bylaws of the Company, effective May 9, 2023. (Incorporated by reference to Exhibit 3.1 to the Company's Form 8-K filed with the SEC on May 12, 2023.)
4.1						Senior Indenture, dated as of September 10, 2025, among the Company, the Subsidiary Guarantors and Computershare Trust Company, N.A., as trustee, relating to the 4.750% Senior Notes due 2034. (Incorporated by reference to Exhibit 4.1 to the Company’s Form 8-K filed with the SEC on September 10, 2025.)
31.1						Rule 13a-14(a) Certification of Chief Executive Officer. (Filed herewith.)
31.2						Rule 13a-14(a) Certification of Chief Financial Officer. (Filed herewith.)
32.1						Section 1350 Certification of Chief Executive Officer. (Furnished herewith.)
32.2						Section 1350 Certification of Chief Financial Officer. (Furnished herewith.)
101.INS						XBRL Instance Document - the instance document does not appear in the Interactive Data File because its XBRL tags are embedded within the Inline XBRL document.
101.SCH						Inline XBRL Taxonomy Extension Schema Document.
101.CAL						Inline XBRL Taxonomy Extension Calculation Linkbase Document.
101.DEF						Inline XBRL Taxonomy Extension Definition Linkbase Document.
101.LAB						Inline XBRL Taxonomy Label Linkbase Document.
101.PRE						Inline XBRL Taxonomy Extension Presentation Linkbase Document.
104						Cover Page Interactive Data File. (Formatted as Inline XBRL and contained in Exhibit 101.)

IRON MOUNTAIN SEPTEMBER 30, 2025 FORM 10-Q 51

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Part II. Other Information

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 thereunto duly authorized.

			IRON MOUNTAIN INCORPORATED
			By:			/s/ DANIEL BORGES
						Daniel Borges  Senior Vice President, Chief Accounting Officer

Dated: November 5, 2025

IRON MOUNTAIN SEPTEMBER 30, 2025 FORM 10-Q 52

FAQ

How did IRM’s Q3 2025 revenue and earnings compare year over year (IRM)?

Q3 revenue was $1,754,093 vs $1,557,358 a year ago. Net income attributable to IRM was $84,290 vs a loss of $33,620.

What were Iron Mountain’s key cash flow and capex figures year to date (IRM)?

Operating cash flow was $840,001, and capital expenditures were $1,755,383 for the nine months ended September 30, 2025.

How much debt does IRM have and what changed in Q3 2025?

Long‑term debt (net of current) was $15,494,236, up from $13,003,977, reflecting funding for growth and the Euro notes issuance.

What financing transaction did IRM complete in September 2025?

IRM issued €1,200,000,000 4.75% Euro senior notes due 2034, with $1,390,651 in net proceeds used to repay the revolver and to repay GBP notes.

How is the data center business trending for IRM?

Q3 2025 data center storage rental revenue was $201,383, up from $150,796 in Q3 2024.

What dividends did IRM declare and pay in 2025?

IRM paid quarterly dividends of $0.785 per share in 2025 and declared $0.864 per share for stockholders of record on December 15, 2025.

How many IRM shares were outstanding recently?

As of October 31, 2025, IRM had 295,589,491 shares of common stock outstanding.