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                    <ccc>XXXXXXXX</ccc>
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            <issuerCik>0001488139</issuerCik>
            <issuerName>AMERESCO, INC.</issuerName>
            <secFileNumber>001-34811</secFileNumber>
            <issuerAddress>
                <ns2:street1>111 Speen Street,</ns2:street1>
                <ns2:street2>Suite 410</ns2:street2>
                <ns2:city>Framingham</ns2:city>
                <ns2:stateOrCountry>MA</ns2:stateOrCountry>
                <ns2:zipCode>01701</ns2:zipCode>
            </issuerAddress>
            <issuerContactPhone>508-661-2200</issuerContactPhone>
            <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>JENNIFER MILLER</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
            <relationshipsToIssuer>
                <relationshipToIssuer>Director</relationshipToIssuer>
            </relationshipsToIssuer>
        </issuerInfo>
        <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>40000</noOfUnitsSold>
            <aggregateMarketValue>842600.00</aggregateMarketValue>
            <noOfUnitsOutstanding>52442751</noOfUnitsOutstanding>
            <approxSaleDate>02/03/2025</approxSaleDate>
            <securitiesExchangeName>NYSE</securitiesExchangeName>
        </securitiesInformation>
        <securitiesToBeSold>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <acquiredDate>02/03/2025</acquiredDate>
            <natureOfAcquisitionTransaction>Stock Option Exercise</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>ISSUER</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>40000</amountOfSecuritiesAcquired>
            <paymentDate>02/03/2025</paymentDate>
            <natureOfPayment>Cash</natureOfPayment>
        </securitiesToBeSold>
        <nothingToReportFlagOnSecuritiesSoldInPast3Months>Y</nothingToReportFlagOnSecuritiesSoldInPast3Months>
        <noticeSignature>
            <noticeDate>02/03/2025</noticeDate>
            <planAdoptionDates>
                <planAdoptionDate>05/22/2023</planAdoptionDate>
            </planAdoptionDates>
            <signature>/s/ Jennifer Miller</signature>
        </noticeSignature>
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144
0001633385
XXXXXXXX
LIVE
0001488139
AMERESCO, INC.
001-34811
111 Speen Street,
Suite 410
Framingham
MA
01701
508-661-2200
JENNIFER MILLER
Director
Common
Morgan Stanley Smith Barney LLC Executive Financial Services
1 New York Plaza
8th Floor
New York
NY
10004
40000
842600.00
52442751
02/03/2025
NYSE
Common
02/03/2025
Stock Option Exercise
ISSUER
N
40000
02/03/2025
Cash
Y
02/03/2025
05/22/2023
/s/ Jennifer Miller