<?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>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 Clearing Services</name>
        <address>
          <com:street1>1 N. Jefferson Ave.</com:street1>
          <com:city>St. Louis</com:city>
          <com:stateOrCountry>MO</com:stateOrCountry>
          <com:zipCode>63103</com:zipCode>
        </address>
      </brokerOrMarketmakerDetails>
      <noOfUnitsSold>1000</noOfUnitsSold>
      <aggregateMarketValue>65246.18</aggregateMarketValue>
      <noOfUnitsOutstanding>85409645</noOfUnitsOutstanding>
      <approxSaleDate>08/05/2024</approxSaleDate>
      <securitiesExchangeName>Nasdaq</securitiesExchangeName>
    </securitiesInformation>
    <securitiesToBeSold>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <acquiredDate>12/27/2021</acquiredDate>
      <natureOfAcquisitionTransaction>Gift</natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>Alan Trefler</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>Y</isGiftTransaction>
      <donarAcquiredDate>05/08/1997</donarAcquiredDate>
      <amountOfSecuritiesAcquired>230</amountOfSecuritiesAcquired>
      <natureOfPayment>N/A</natureOfPayment>
    </securitiesToBeSold>
    <securitiesToBeSold>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <acquiredDate>12/23/2022</acquiredDate>
      <natureOfAcquisitionTransaction>Gift</natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>Alan Trefler</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>Y</isGiftTransaction>
      <donarAcquiredDate>05/08/1997</donarAcquiredDate>
      <amountOfSecuritiesAcquired>770</amountOfSecuritiesAcquired>
      <natureOfPayment>N/A</natureOfPayment>
    </securitiesToBeSold>
    <nothingToReportFlagOnSecuritiesSoldInPast3Months>Y</nothingToReportFlagOnSecuritiesSoldInPast3Months>
    <remarks>Shares were in the account of Ashley Berger Irrevocable Trust, Pamela Trefler TTEE. Pamela Trefler resides in the same household as Alan Trefler who is an Officer and 10 percent shareholder of PEGA</remarks>
    <noticeSignature>
      <noticeDate>08/05/2024</noticeDate>
      <signature>Pamela Trefler (TTEE on acct)</signature>
    </noticeSignature>
  </formData>
</edgarSubmission>
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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 Clearing Services
1 N. Jefferson Ave.
St. Louis
MO
63103
1000
65246.18
85409645
08/05/2024
Nasdaq
Common
12/27/2021
Gift
Alan Trefler
Y
05/08/1997
230
N/A
Common
12/23/2022
Gift
Alan Trefler
Y
05/08/1997
770
N/A
Y
Shares were in the account of Ashley Berger Irrevocable Trust, Pamela Trefler TTEE. Pamela Trefler resides in the same household as Alan Trefler who is an Officer and 10 percent shareholder of PEGA
08/05/2024
Pamela Trefler (TTEE on acct)