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                    <ccc>XXXXXXXX</ccc>
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            <liveTestFlag>LIVE</liveTestFlag>



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        <issuerInfo>
            <issuerCik>0001013237</issuerCik>
            <issuerName>FACTSET RESEARCH SYSTEMS INC.</issuerName>
            <secFileNumber>001-11869</secFileNumber>
            <issuerAddress>
                <ns2:street1>45 Glover Avenue</ns2:street1>
                <ns2:city>Norwalk</ns2:city>
                <ns2:stateOrCountry>CT</ns2:stateOrCountry>
                <ns2:zipCode>06850</ns2:zipCode>
            </issuerAddress>
            <issuerContactPhone>203-810-1000</issuerContactPhone>
            <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>ABRAMS FAMILY TRUST </nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
            <relationshipsToIssuer>
                <relationshipToIssuer>Director</relationshipToIssuer>
            </relationshipsToIssuer>
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        <securitiesInformation>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <brokerOrMarketmakerDetails>
                <name>Morgan Stanley Smith Barney LLC Executive Financial Services</name>
                <address>
                    <ns2:street1>1 New York Plaza</ns2:street1>
                    <ns2:street2>8th Floor</ns2:street2>
                    <ns2:city>New York</ns2:city>
                    <ns2:stateOrCountry>NY</ns2:stateOrCountry>
                    <ns2:zipCode>10004</ns2:zipCode>
                </address>
            </brokerOrMarketmakerDetails>
            <noOfUnitsSold>2375</noOfUnitsSold>
            <aggregateMarketValue>999195.75</aggregateMarketValue>
            <noOfUnitsOutstanding>38115834</noOfUnitsOutstanding>
            <approxSaleDate>06/25/2024</approxSaleDate>
            <securitiesExchangeName>NYSE</securitiesExchangeName>
        </securitiesInformation>
        <securitiesToBeSold>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <acquiredDate>01/10/2019</acquiredDate>
            <natureOfAcquisitionTransaction>Exercise of options under a registered plan</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>2375</amountOfSecuritiesAcquired>
            <paymentDate>01/10/2019</paymentDate>
            <natureOfPayment>Cash</natureOfPayment>
        </securitiesToBeSold>
        <nothingToReportFlagOnSecuritiesSoldInPast3Months>Y</nothingToReportFlagOnSecuritiesSoldInPast3Months>
        <noticeSignature>
            <noticeDate>06/25/2024</noticeDate>
            <planAdoptionDates/>
            <signature>/s/ Robin Ann Abrams, Trustee</signature>
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144
0001282677
XXXXXXXX
LIVE
0001013237
FACTSET RESEARCH SYSTEMS INC.
001-11869
45 Glover Avenue
Norwalk
CT
06850
203-810-1000
ABRAMS FAMILY TRUST
Director
Common
Morgan Stanley Smith Barney LLC Executive Financial Services
1 New York Plaza
8th Floor
New York
NY
10004
2375
999195.75
38115834
06/25/2024
NYSE
Common
01/10/2019
Exercise of options under a registered plan
Issuer
N
2375
01/10/2019
Cash
Y
06/25/2024
/s/ Robin Ann Abrams, Trustee