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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>225 WYMAN STREET</com:street1>
        <com:street2>STE 300</com:street2>
        <com:city>WALTHAM</com:city>
        <com:stateOrCountry>MA</com:stateOrCountry>
        <com:zipCode>02451-1293</com:zipCode>
      </issuerAddress>
      <issuerContactPhone>6173749600</issuerContactPhone>
      <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>TREFLER ALAN</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
      <relationshipsToIssuer>
        <relationshipToIssuer>Officer</relationshipToIssuer>
        <relationshipToIssuer>Director</relationshipToIssuer>
        <relationshipToIssuer>10% Stockholder</relationshipToIssuer>
      </relationshipsToIssuer>
    </issuerInfo>
    <securitiesInformation>
      <securitiesClassTitle>common</securitiesClassTitle>
      <brokerOrMarketmakerDetails>
        <name>Wells Fargo Clearing Services</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>20000</noOfUnitsSold>
      <aggregateMarketValue>1877067.55</aggregateMarketValue>
      <noOfUnitsOutstanding>85118570</noOfUnitsOutstanding>
      <approxSaleDate>05/05/2025</approxSaleDate>
      <securitiesExchangeName>Nasdaq</securitiesExchangeName>
    </securitiesInformation>
    <securitiesToBeSold>
      <securitiesClassTitle>common</securitiesClassTitle>
      <acquiredDate>12/24/2024</acquiredDate>
      <natureOfAcquisitionTransaction>Gift</natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>Alan Trefler</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>Y</isGiftTransaction>
      <donarAcquiredDate>05/08/1997</donarAcquiredDate>
      <amountOfSecuritiesAcquired>14000</amountOfSecuritiesAcquired>
      <paymentDate>12/24/2024</paymentDate>
      <natureOfPayment>N/A</natureOfPayment>
    </securitiesToBeSold>
    <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>6000</amountOfSecuritiesAcquired>
      <paymentDate>12/27/2021</paymentDate>
      <natureOfPayment>N/A</natureOfPayment>
    </securitiesToBeSold>
    <nothingToReportFlagOnSecuritiesSoldInPast3Months>N</nothingToReportFlagOnSecuritiesSoldInPast3Months>
    <securitiesSoldInPast3Months>
      <sellerDetails>
        <name>Alan Trefler</name>
        <address>
          <com:street1>225 Wyman Street</com:street1>
          <com:city>Waltham</com:city>
          <com:stateOrCountry>MA</com:stateOrCountry>
          <com:zipCode>02451</com:zipCode>
        </address>
      </sellerDetails>
      <securitiesClassTitle>Pegasystems, Inc.</securitiesClassTitle>
      <saleDate>04/17/2025</saleDate>
      <amountOfSecuritiesSold>31554</amountOfSecuritiesSold>
      <grossProceeds>2162798.32</grossProceeds>
    </securitiesSoldInPast3Months>
    <securitiesSoldInPast3Months>
      <sellerDetails>
        <name>Alan Trefler</name>
        <address>
          <com:street1>225 Wyman Street</com:street1>
          <com:city>Waltham</com:city>
          <com:stateOrCountry>MA</com:stateOrCountry>
          <com:zipCode>02451</com:zipCode>
        </address>
      </sellerDetails>
      <securitiesClassTitle>Pegasystems, Inc.</securitiesClassTitle>
      <saleDate>04/16/2025</saleDate>
      <amountOfSecuritiesSold>31500</amountOfSecuritiesSold>
      <grossProceeds>2154981.35</grossProceeds>
    </securitiesSoldInPast3Months>
    <securitiesSoldInPast3Months>
      <sellerDetails>
        <name>Alan Trefler</name>
        <address>
          <com:street1>225 Wyman Street</com:street1>
          <com:city>Waltham</com:city>
          <com:stateOrCountry>MA</com:stateOrCountry>
          <com:zipCode>02451</com:zipCode>
        </address>
      </sellerDetails>
      <securitiesClassTitle>Pegasystems, Inc.</securitiesClassTitle>
      <saleDate>03/12/2025</saleDate>
      <amountOfSecuritiesSold>31500</amountOfSecuritiesSold>
      <grossProceeds>2286270.00</grossProceeds>
    </securitiesSoldInPast3Months>
    <securitiesSoldInPast3Months>
      <sellerDetails>
        <name>Alan Trefler</name>
        <address>
          <com:street1>225 Wyman Street</com:street1>
          <com:city>Waltham</com:city>
          <com:stateOrCountry>MA</com:stateOrCountry>
          <com:zipCode>02451</com:zipCode>
        </address>
      </sellerDetails>
      <securitiesClassTitle>Pegasystems, Inc.</securitiesClassTitle>
      <saleDate>03/11/2025</saleDate>
      <amountOfSecuritiesSold>31500</amountOfSecuritiesSold>
      <grossProceeds>2234295.00</grossProceeds>
    </securitiesSoldInPast3Months>
    <securitiesSoldInPast3Months>
      <sellerDetails>
        <name>Alan Trefler</name>
        <address>
          <com:street1>225 Wyman Street</com:street1>
          <com:city>Waltham</com:city>
          <com:stateOrCountry>MA</com:stateOrCountry>
          <com:zipCode>02451</com:zipCode>
        </address>
      </sellerDetails>
      <securitiesClassTitle>Pegasystems, Inc.</securitiesClassTitle>
      <saleDate>02/26/2025</saleDate>
      <amountOfSecuritiesSold>31500</amountOfSecuritiesSold>
      <grossProceeds>2493225.00</grossProceeds>
    </securitiesSoldInPast3Months>
    <securitiesSoldInPast3Months>
      <sellerDetails>
        <name>Alan Trefler</name>
        <address>
          <com:street1>225 Wyman Street</com:street1>
          <com:city>Waltham</com:city>
          <com:stateOrCountry>MA</com:stateOrCountry>
          <com:zipCode>02451</com:zipCode>
        </address>
      </sellerDetails>
      <securitiesClassTitle>Pegasystems, Inc.</securitiesClassTitle>
      <saleDate>02/25/2025</saleDate>
      <amountOfSecuritiesSold>31500</amountOfSecuritiesSold>
      <grossProceeds>2437470.00</grossProceeds>
    </securitiesSoldInPast3Months>
    <remarks>shares were sold in the Trefler Foundation, Alan Trefler is an officer of the foundation and an officer, director and 10 percent shareholder of Pegasystems, Inc.</remarks>
    <noticeSignature>
      <noticeDate>05/05/2025</noticeDate>
      <signature>Alan Trefler</signature>
    </noticeSignature>
  </formData>
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144
0001032235
XXXXXXXX
LIVE
0001013857
PEGASYSTEMS INC
001-11859
225 WYMAN STREET
STE 300
WALTHAM
MA
02451-1293
6173749600
TREFLER ALAN
Officer
Director
10% Stockholder
common
Wells Fargo Clearing Services
1 North Jefferson Avenue
St. Louis
MO
63103
20000
1877067.55
85118570
05/05/2025
Nasdaq
common
12/24/2024
Gift
Alan Trefler
Y
05/08/1997
14000
12/24/2024
N/A
common
12/27/2021
Gift
Alan Trefler
Y
05/08/1997
6000
12/27/2021
N/A
N
Alan Trefler
225 Wyman Street
Waltham
MA
02451
Pegasystems, Inc.
04/17/2025
31554
2162798.32
Alan Trefler
225 Wyman Street
Waltham
MA
02451
Pegasystems, Inc.
04/16/2025
31500
2154981.35
Alan Trefler
225 Wyman Street
Waltham
MA
02451
Pegasystems, Inc.
03/12/2025
31500
2286270.00
Alan Trefler
225 Wyman Street
Waltham
MA
02451
Pegasystems, Inc.
03/11/2025
31500
2234295.00
Alan Trefler
225 Wyman Street
Waltham
MA
02451
Pegasystems, Inc.
02/26/2025
31500
2493225.00
Alan Trefler
225 Wyman Street
Waltham
MA
02451
Pegasystems, Inc.
02/25/2025
31500
2437470.00
shares were sold in the Trefler Foundation, Alan Trefler is an officer of the foundation and an officer, director and 10 percent shareholder of Pegasystems, Inc.
05/05/2025
Alan Trefler