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      <submissionType>144</submissionType>
      <filerInfo>
        <filer>
          <filerCredentials>
            <cik>0001222574</cik>
            <ccc>XXXXXXXX</ccc>
          </filerCredentials>
        </filer>
        <liveTestFlag>LIVE</liveTestFlag>
  
  
  
      </filerInfo>
    </headerData>
    <formData>
      <issuerInfo>
        <issuerCik>0001013857</issuerCik>
        <issuerName>PEGASYSTEMS INC</issuerName>
        <secFileNumber>001-11859</secFileNumber>
        <issuerAddress>
          <com:street1>ONE MAIN STREET</com:street1>
          <com:city>CAMBRIDGE</com:city>
          <com:stateOrCountry>MA</com:stateOrCountry>
          <com:zipCode>02142-1531</com:zipCode>
        </issuerAddress>
        <issuerContactPhone>6173749600</issuerContactPhone>
        <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>JONES RICHARD H</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
        <relationshipsToIssuer>
          <relationshipToIssuer>Director</relationshipToIssuer>
        </relationshipsToIssuer>
      </issuerInfo>
      <securitiesInformation>
        <securitiesClassTitle>common</securitiesClassTitle>
        <brokerOrMarketmakerDetails>
          <name>Cowen &amp; Co</name>
          <address>
            <com:street1>599 Lexington Ave</com:street1>
            <com:city>New York</com:city>
            <com:stateOrCountry>NY</com:stateOrCountry>
            <com:zipCode>10023</com:zipCode>
          </address>
        </brokerOrMarketmakerDetails>
        <noOfUnitsSold>10000</noOfUnitsSold>
        <aggregateMarketValue>698795.59</aggregateMarketValue>
        <noOfUnitsOutstanding>85400000</noOfUnitsOutstanding>
        <approxSaleDate>09/03/2024</approxSaleDate>
        <securitiesExchangeName>nasdaq</securitiesExchangeName>
      </securitiesInformation>
      <securitiesToBeSold>
        <securitiesClassTitle>common</securitiesClassTitle>
        <acquiredDate>07/12/2007</acquiredDate>
        <natureOfAcquisitionTransaction>Directly from company</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Pegasystems</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>256986</amountOfSecuritiesAcquired>
        <paymentDate>07/12/2007</paymentDate>
        <natureOfPayment>contribution</natureOfPayment>
      </securitiesToBeSold>
      <nothingToReportFlagOnSecuritiesSoldInPast3Months>N</nothingToReportFlagOnSecuritiesSoldInPast3Months>
      <securitiesSoldInPast3Months>
        <sellerDetails>
          <name>Richard H, Jones Rev Trust Dated 8/17/98</name>
          <address>
            <com:street1>One Main St</com:street1>
            <com:city>Cambridge</com:city>
            <com:stateOrCountry>MA</com:stateOrCountry>
            <com:zipCode>02142</com:zipCode>
          </address>
        </sellerDetails>
        <securitiesClassTitle>common</securitiesClassTitle>
        <saleDate>08/01/2024</saleDate>
        <amountOfSecuritiesSold>15271</amountOfSecuritiesSold>
        <grossProceeds>1057575.68</grossProceeds>
      </securitiesSoldInPast3Months>
      <securitiesSoldInPast3Months>
        <sellerDetails>
          <name>Richard H. Jones Rev Trust Dated 8/17/98</name>
          <address>
            <com:street1>OneMain St</com:street1>
            <com:city>Cambridge</com:city>
            <com:stateOrCountry>MA</com:stateOrCountry>
            <com:zipCode>02142</com:zipCode>
          </address>
        </sellerDetails>
        <securitiesClassTitle>common</securitiesClassTitle>
        <saleDate>08/23/2024</saleDate>
        <amountOfSecuritiesSold>4729</amountOfSecuritiesSold>
        <grossProceeds>331176.43</grossProceeds>
      </securitiesSoldInPast3Months>
      <securitiesSoldInPast3Months>
        <sellerDetails>
          <name>Richard H. Jones Rev Trust Dated 08/17/98</name>
          <address>
            <com:street1>One Main St</com:street1>
            <com:city>Cambridge</com:city>
            <com:stateOrCountry>MA</com:stateOrCountry>
            <com:zipCode>02142</com:zipCode>
          </address>
        </sellerDetails>
        <securitiesClassTitle>common</securitiesClassTitle>
        <saleDate>09/03/2024</saleDate>
        <amountOfSecuritiesSold>10000</amountOfSecuritiesSold>
        <grossProceeds>698795.59</grossProceeds>
      </securitiesSoldInPast3Months>
      <noticeSignature>
        <noticeDate>09/03/2024</noticeDate>
        <planAdoptionDates>
          <planAdoptionDate>08/17/1998</planAdoptionDate>
        </planAdoptionDates>
        <signature>/s/ Richard H. Jones</signature>
      </noticeSignature>
    </formData>
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text: 144
  0001222574
  XXXXXXXX
  LIVE
  0001013857
  PEGASYSTEMS INC
  001-11859
  ONE MAIN STREET
  CAMBRIDGE
  MA
  02142-1531
  6173749600
  JONES RICHARD H
  Director
  common
  Cowen & Co
  599 Lexington Ave
  New York
  NY
  10023
  10000
  698795.59
  85400000
  09/03/2024
  nasdaq
  common
  07/12/2007
  Directly from company
  Pegasystems
  N
  256986
  07/12/2007
  contribution
  N
  Richard H, Jones Rev Trust Dated 8/17/98
  One Main St
  Cambridge
  MA
  02142
  common
  08/01/2024
  15271
  1057575.68
  Richard H. Jones Rev Trust Dated 8/17/98
  OneMain St
  Cambridge
  MA
  02142
  common
  08/23/2024
  4729
  331176.43
  Richard H. Jones Rev Trust Dated 08/17/98
  One Main St
  Cambridge
  MA
  02142
  common
  09/03/2024
  10000
  698795.59
  09/03/2024
  08/17/1998
  /s/ Richard H. Jones