<?xml version="1.0" encoding="UTF-8"?><edgarSubmission xmlns="http://www.sec.gov/edgar/ownership" xmlns:ns2="http://www.sec.gov/edgar/common">
    <headerData>
        <submissionType>144</submissionType>
        <filerInfo>
            <filer>
                <filerCredentials>
                    <cik>0001469131</cik>
                    <ccc>XXXXXXXX</ccc>
                </filerCredentials>
            </filer>
            <liveTestFlag>LIVE</liveTestFlag>



        </filerInfo>
    </headerData>
    <formData>
        <issuerInfo>
            <issuerCik>0001060955</issuerCik>
            <issuerName>ICON PLC</issuerName>
            <secFileNumber>333-08704</secFileNumber>
            <issuerAddress>
                <ns2:street1>South County Business Park</ns2:street1>
                <ns2:street2>Leopardstown</ns2:street2>
                <ns2:city>Dublin 18</ns2:city>
                <ns2:stateOrCountry>L2</ns2:stateOrCountry>
                <ns2:zipCode>D18 X5R3</ns2:zipCode>
            </issuerAddress>
            <issuerContactPhone>353-1-291-2000</issuerContactPhone>
            <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>STEPHEN CUTLER</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
            <relationshipsToIssuer>
                <relationshipToIssuer>Officer</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>15442</noOfUnitsSold>
            <aggregateMarketValue>5188132.13</aggregateMarketValue>
            <noOfUnitsOutstanding>82495086</noOfUnitsOutstanding>
            <approxSaleDate>03/06/2024</approxSaleDate>
            <securitiesExchangeName>NASDAQ</securitiesExchangeName>
        </securitiesInformation>
        <securitiesToBeSold>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <acquiredDate>03/03/2021</acquiredDate>
            <natureOfAcquisitionTransaction>Restricted stock vesting under a registered plan</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>1636</amountOfSecuritiesAcquired>
            <paymentDate>03/08/2024</paymentDate>
            <natureOfPayment>Services Rendered</natureOfPayment>
        </securitiesToBeSold>
        <securitiesToBeSold>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <acquiredDate>03/03/2019</acquiredDate>
            <natureOfAcquisitionTransaction>Restricted stock vesting under a registered plan</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>1981</amountOfSecuritiesAcquired>
            <paymentDate>03/08/2024</paymentDate>
            <natureOfPayment>Services Rendered</natureOfPayment>
        </securitiesToBeSold>
        <securitiesToBeSold>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <acquiredDate>03/03/2019</acquiredDate>
            <natureOfAcquisitionTransaction>Performance Stock Units</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>11825</amountOfSecuritiesAcquired>
            <paymentDate>03/08/2024</paymentDate>
            <natureOfPayment>Services Rendered</natureOfPayment>
        </securitiesToBeSold>
        <nothingToReportFlagOnSecuritiesSoldInPast3Months>N</nothingToReportFlagOnSecuritiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>STEPHEN CUTLER</name>
                <address>
                    <ns2:street1>South County Business Park</ns2:street1>
                    <ns2:street2>Leopardstown</ns2:street2>
                    <ns2:city>Dublin 18</ns2:city>
                    <ns2:stateOrCountry>L2</ns2:stateOrCountry>
                    <ns2:zipCode>D18 X5R3</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>03/04/2024</saleDate>
            <amountOfSecuritiesSold>6007</amountOfSecuritiesSold>
            <grossProceeds>1935996.03</grossProceeds>
        </securitiesSoldInPast3Months>
        <noticeSignature>
            <noticeDate>03/06/2024</noticeDate>
            <planAdoptionDates/>
            <signature>/s/ Stephen Cutler</signature>
        </noticeSignature>
    </formData>
</edgarSubmission>
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144
0001469131
XXXXXXXX
LIVE
0001060955
ICON PLC
333-08704
South County Business Park
Leopardstown
Dublin 18
L2
D18 X5R3
353-1-291-2000
STEPHEN CUTLER
Officer
Common
Morgan Stanley Smith Barney LLC Executive Financial Services
1 New York Plaza
8th Floor
New York
NY
10004
15442
5188132.13
82495086
03/06/2024
NASDAQ
Common
03/03/2021
Restricted stock vesting under a registered plan
Issuer
N
1636
03/08/2024
Services Rendered
Common
03/03/2019
Restricted stock vesting under a registered plan
Issuer
N
1981
03/08/2024
Services Rendered
Common
03/03/2019
Performance Stock Units
Issuer
N
11825
03/08/2024
Services Rendered
N
STEPHEN CUTLER
South County Business Park
Leopardstown
Dublin 18
L2
D18 X5R3
Common
03/04/2024
6007
1935996.03
03/06/2024
/s/ Stephen Cutler