<SEC-DOCUMENT>0001613777-26-000002.txt : 20260218
<SEC-HEADER>0001613777-26-000002.hdr.sgml : 20260218
<ACCEPTANCE-DATETIME>20260218171540
ACCESSION NUMBER:		0001613777-26-000002
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20260216
FILED AS OF DATE:		20260218
DATE AS OF CHANGE:		20260218

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Hytinen Barry
		CENTRAL INDEX KEY:			0001613777
		ORGANIZATION NAME:           	

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-13045
		FILM NUMBER:		26650112

	MAIL ADDRESS:	
		STREET 1:		C/O IRON MOUNTAIN INC
		STREET 2:		85 NEW HAMPSHIRE AVENUE, SUITE 150
		CITY:			PORTSMOUTH
		STATE:			NH
		ZIP:			03801

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			IRON MOUNTAIN INC
		CENTRAL INDEX KEY:			0001020569
		STANDARD INDUSTRIAL CLASSIFICATION:	REAL ESTATE INVESTMENT TRUSTS [6798]
		ORGANIZATION NAME:           	05 Real Estate & Construction
		EIN:				232588479
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		85 NEW HAMPSHIRE AVENUE, SUITE 150
		STREET 2:		PEASE INTERNATIONAL TRADEPORT
		CITY:			PORTSMOUTH
		STATE:			NH
		ZIP:			03801
		BUSINESS PHONE:		617-535-4781

	MAIL ADDRESS:	
		STREET 1:		1101 ENTERPRISE DRIVE
		CITY:			ROYERSFORD
		STATE:			PA
		ZIP:			19468

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	IRON MOUNTAIN INC/PA
		DATE OF NAME CHANGE:	20000201

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	PIERCE LEAHY CORP
		DATE OF NAME CHANGE:	19960807
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wk-form4_1771452938.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0508</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2026-02-16</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001020569</issuerCik>
        <issuerName>IRON MOUNTAIN INC</issuerName>
        <issuerTradingSymbol>IRM</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001613777</rptOwnerCik>
            <rptOwnerName>Hytinen Barry</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O IRON MOUNTAIN INCORPORATED</rptOwnerStreet1>
            <rptOwnerStreet2>85 NEW HAMPSHIRE AVENUE, SUITE 150</rptOwnerStreet2>
            <rptOwnerCity>PORTSMOUTH</rptOwnerCity>
            <rptOwnerState>NH</rptOwnerState>
            <rptOwnerZipCode>03801</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>EVP and CFO</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <aff10b5One>0</aff10b5One>

    <nonDerivativeTable></nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Performance Units</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F1"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2026-02-16</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>166412</value>
                    <footnoteId id="F2"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F3"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F3"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock, par value $.01 per share</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>166412</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>232977</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Each Performance Unit (&quot;PU&quot;) represents a contingent right to receive one share of Iron Mountain Incorporated common stock (&quot;Common Stock&quot;).</footnote>
        <footnote id="F2">The PUs were initially granted to the Reporting Person on March 1, 2023. This Form 4 is being filed to reflect the determination by the Compensation Committee, effective as of February 16, 2026, of the actual award of PUs under the grant after completion of the relevant performance period.</footnote>
        <footnote id="F3">The PU were initially granted to the Reporting Person on March 1, 2023, and will fully vest on March 1, 2026.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Barry Hytinen</signatureName>
        <signatureDate>2026-02-18</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
