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    <filerInfo>
      <filer>
        <filerCredentials>
          <cik>0001032235</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>TREFLER ALAN</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
      <relationshipsToIssuer>
        <relationshipToIssuer>Member of immediate family of any of the foregoing</relationshipToIssuer>
      </relationshipsToIssuer>
    </issuerInfo>
    <securitiesInformation>
      <securitiesClassTitle>common</securitiesClassTitle>
      <brokerOrMarketmakerDetails>
        <name>Wells Fargo Advisors</name>
        <address>
          <com:street1>1 North Jefferson Avenue</com:street1>
          <com:city>St. Louis</com:city>
          <com:stateOrCountry>MO</com:stateOrCountry>
          <com:zipCode>63103</com:zipCode>
        </address>
      </brokerOrMarketmakerDetails>
      <noOfUnitsSold>10000</noOfUnitsSold>
      <aggregateMarketValue>502763.32</aggregateMarketValue>
      <noOfUnitsOutstanding>82961204</noOfUnitsOutstanding>
      <approxSaleDate>06/14/2023</approxSaleDate>
      <securitiesExchangeName>Nasdaq</securitiesExchangeName>
    </securitiesInformation>
    <securitiesToBeSold>
      <securitiesClassTitle>common</securitiesClassTitle>
      <acquiredDate>12/26/2019</acquiredDate>
      <natureOfAcquisitionTransaction>Gift</natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>Alan Trefler</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>Y</isGiftTransaction>
      <donarAcquiredDate>09/16/2008</donarAcquiredDate>
      <amountOfSecuritiesAcquired>10000</amountOfSecuritiesAcquired>
      <natureOfPayment>N/A</natureOfPayment>
    </securitiesToBeSold>
    <nothingToReportFlagOnSecuritiesSoldInPast3Months>N</nothingToReportFlagOnSecuritiesSoldInPast3Months>
    <securitiesSoldInPast3Months>
      <sellerDetails>
        <name>Trefler Foundation</name>
        <address>
          <com:street1>One Main Street</com:street1>
          <com:city>Cambridge</com:city>
          <com:stateOrCountry>ME</com:stateOrCountry>
          <com:zipCode>02142</com:zipCode>
        </address>
      </sellerDetails>
      <securitiesClassTitle>PegaSystems, Inc.</securitiesClassTitle>
      <saleDate>03/16/2023</saleDate>
      <amountOfSecuritiesSold>12000</amountOfSecuritiesSold>
      <grossProceeds>550696.65</grossProceeds>
    </securitiesSoldInPast3Months>
    <remarks>shares were sold in the Trefler Foundation, Pamela Trefler, officer.  Pamela Trefler is the spouse of an officer of the issuer.</remarks>
    <noticeSignature>
      <noticeDate>06/14/2023</noticeDate>
      <signature>Pamela Trefler</signature>
    </noticeSignature>
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144
0001032235
XXXXXXXX
LIVE
0001013857
PEGASYSTEMS INC
001-11859
ONE MAIN STREET
CAMBRIDGE
MA
02142-1531
6173749600
TREFLER ALAN
Member of immediate family of any of the foregoing
common
Wells Fargo Advisors
1 North Jefferson Avenue
St. Louis
MO
63103
10000
502763.32
82961204
06/14/2023
Nasdaq
common
12/26/2019
Gift
Alan Trefler
Y
09/16/2008
10000
N/A
N
Trefler Foundation
One Main Street
Cambridge
ME
02142
PegaSystems, Inc.
03/16/2023
12000
550696.65
shares were sold in the Trefler Foundation, Pamela Trefler, officer.  Pamela Trefler is the spouse of an officer of the issuer.
06/14/2023
Pamela Trefler