<?xml version="1.0" encoding="UTF-8"?><edgarSubmission xmlns="http://www.sec.gov/edgar/ownership" xmlns:com="http://www.sec.gov/edgar/common">
  <headerData>
    <submissionType>144</submissionType>
    <filerInfo>
      <filer>
        <filerCredentials>
          <cik>0001203539</cik>
          <ccc>XXXXXXXX</ccc>
        </filerCredentials>
      </filer>
      <liveTestFlag>LIVE</liveTestFlag>



    </filerInfo>
  </headerData>
  <formData>
    <issuerInfo>
      <issuerCik>0000798354</issuerCik>
      <issuerName>FISERV INC</issuerName>
      <secFileNumber>001-38962</secFileNumber>
      <issuerAddress>
        <com:street1>255 FISERV DR</com:street1>
        <com:street2>PO BOX 979</com:street2>
        <com:city>BROOKFIELD</com:city>
        <com:stateOrCountry>WI</com:stateOrCountry>
        <com:zipCode>53045</com:zipCode>
      </issuerAddress>
      <issuerContactPhone>4148795000</issuerContactPhone>
      <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>DAVIS ALISON</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
      <relationshipsToIssuer>
        <relationshipToIssuer>Former Director</relationshipToIssuer>
      </relationshipsToIssuer>
    </issuerInfo>
    <securitiesInformation>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <brokerOrMarketmakerDetails>
        <name>Fidelity Brokerage Services LLC</name>
        <address>
          <com:street1>900 Salem Street</com:street1>
          <com:city>Smithfield</com:city>
          <com:stateOrCountry>RI</com:stateOrCountry>
          <com:zipCode>02917</com:zipCode>
        </address>
      </brokerOrMarketmakerDetails>
      <noOfUnitsSold>2000</noOfUnitsSold>
      <aggregateMarketValue>242000.00</aggregateMarketValue>
      <noOfUnitsOutstanding>617309915</noOfUnitsOutstanding>
      <approxSaleDate>06/27/2023</approxSaleDate>
      <securitiesExchangeName>NYSE</securitiesExchangeName>
    </securitiesInformation>
    <securitiesToBeSold>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <acquiredDate>06/27/2023</acquiredDate>
      <natureOfAcquisitionTransaction>Option Granted 11/18/2014</natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>N</isGiftTransaction>
      <amountOfSecuritiesAcquired>2000</amountOfSecuritiesAcquired>
      <paymentDate>06/27/2023</paymentDate>
      <natureOfPayment>Cash</natureOfPayment>
    </securitiesToBeSold>
    <nothingToReportFlagOnSecuritiesSoldInPast3Months>N</nothingToReportFlagOnSecuritiesSoldInPast3Months>
    <securitiesSoldInPast3Months>
      <sellerDetails>
        <name>Alison Davis</name>
        <address>
          <com:street1>255 Fiserv Drive</com:street1>
          <com:city>Brookfield</com:city>
          <com:stateOrCountry>WI</com:stateOrCountry>
          <com:zipCode>53045</com:zipCode>
        </address>
      </sellerDetails>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <saleDate>06/21/2023</saleDate>
      <amountOfSecuritiesSold>3297</amountOfSecuritiesSold>
      <grossProceeds>396262.01</grossProceeds>
    </securitiesSoldInPast3Months>
    <securitiesSoldInPast3Months>
      <sellerDetails>
        <name>Alison Davis</name>
        <address>
          <com:street1>255 Fiserv Drive</com:street1>
          <com:city>Brookfield</com:city>
          <com:stateOrCountry>WI</com:stateOrCountry>
          <com:zipCode>53045</com:zipCode>
        </address>
      </sellerDetails>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <saleDate>06/13/2023</saleDate>
      <amountOfSecuritiesSold>3500</amountOfSecuritiesSold>
      <grossProceeds>414928.05</grossProceeds>
    </securitiesSoldInPast3Months>
    <securitiesSoldInPast3Months>
      <sellerDetails>
        <name>Alison Davis</name>
        <address>
          <com:street1>255 Fiserv Drive</com:street1>
          <com:city>Brookfield</com:city>
          <com:stateOrCountry>WI</com:stateOrCountry>
          <com:zipCode>53045</com:zipCode>
        </address>
      </sellerDetails>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <saleDate>05/23/2023</saleDate>
      <amountOfSecuritiesSold>1699</amountOfSecuritiesSold>
      <grossProceeds>201773.24</grossProceeds>
    </securitiesSoldInPast3Months>
    <noticeSignature>
      <noticeDate>06/27/2023</noticeDate>
      <signature>/s/ Ryan Riviere, as a duly authorized representative of Fidelity Brokerage Services LLC, as attorney-in-fact for Alison Davis</signature>
    </noticeSignature>
  </formData>
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144
0001203539
XXXXXXXX
LIVE
0000798354
FISERV INC
001-38962
255 FISERV DR
PO BOX 979
BROOKFIELD
WI
53045
4148795000
DAVIS ALISON
Former Director
Common
Fidelity Brokerage Services LLC
900 Salem Street
Smithfield
RI
02917
2000
242000.00
617309915
06/27/2023
NYSE
Common
06/27/2023
Option Granted 11/18/2014
Issuer
N
2000
06/27/2023
Cash
N
Alison Davis
255 Fiserv Drive
Brookfield
WI
53045
Common
06/21/2023
3297
396262.01
Alison Davis
255 Fiserv Drive
Brookfield
WI
53045
Common
06/13/2023
3500
414928.05
Alison Davis
255 Fiserv Drive
Brookfield
WI
53045
Common
05/23/2023
1699
201773.24
06/27/2023
/s/ Ryan Riviere, as a duly authorized representative of Fidelity Brokerage Services LLC, as attorney-in-fact for Alison Davis