<SEC-DOCUMENT>0000798354-25-000156.txt : 20250702
<SEC-HEADER>0000798354-25-000156.hdr.sgml : 20250702
<ACCEPTANCE-DATETIME>20250702162304
ACCESSION NUMBER:		0000798354-25-000156
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20250630
FILED AS OF DATE:		20250702
DATE AS OF CHANGE:		20250702

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Simons Doyle
		CENTRAL INDEX KEY:			0001185922
		ORGANIZATION NAME:           	

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-38962
		FILM NUMBER:		251101484

	MAIL ADDRESS:	
		STREET 1:		220 OCCIDENTAL AVENUE SOUTH
		CITY:			SEATTLE
		STATE:			WA
		ZIP:			98104

	FORMER NAME:	
		FORMER CONFORMED NAME:	SIMONS DOYLE R
		DATE OF NAME CHANGE:	20020904

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			FISERV INC
		CENTRAL INDEX KEY:			0000798354
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-BUSINESS SERVICES, NEC [7389]
		ORGANIZATION NAME:           	07 Trade & Services
		EIN:				391506125
		STATE OF INCORPORATION:			WI
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		600 N. VEL R. PHILLIPS AVENUE
		CITY:			MILWAUKEE
		STATE:			WI
		ZIP:			53203
		BUSINESS PHONE:		2628795000

	MAIL ADDRESS:	
		STREET 1:		600 N. VEL R. PHILLIPS AVENUE
		CITY:			MILWAUKEE
		STATE:			WI
		ZIP:			53203
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wk-form4_1751487777.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0508</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2025-06-30</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000798354</issuerCik>
        <issuerName>FISERV INC</issuerName>
        <issuerTradingSymbol>FI</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001185922</rptOwnerCik>
            <rptOwnerName>Simons Doyle</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>600 N. VEL R. PHILLIPS AVENUE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>MILWAUKEE</rptOwnerCity>
            <rptOwnerState>WI</rptOwnerState>
            <rptOwnerZipCode>53203</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <aff10b5One>0</aff10b5One>

    <nonDerivativeTable></nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Deferred Compensation Notional Units</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F1"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2025-06-30</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>285</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>172.41</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F1"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>285</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>44601</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">These deferred compensation notional units were allocated under the Fiserv, Inc. Non-Employee Director Deferred Compensation Plan (the &quot;Plan&quot;), under which director fees otherwise payable in cash may be deferred in exchange for the allocation of notional units under the Plan. This Form 4 reports the crediting of units under the Plan on June 30, 2025, in respect of $49,038 of deferred compensation. The number of notional units credited is calculated by dividing the amount of compensation that is deferred by the closing price of the company's common stock on the date of deferral, or last business day prior. On June 30, 2025, the closing price of Fiserv's common stock was $172.41 per share. Following cessation of the reporting person's service to the company, each notional unit will be settled in shares of Fiserv common stock on a one-for-one basis.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Eric C. Nelson (attorney-in-fact)</signatureName>
        <signatureDate>2025-07-02</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
