<?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>0001133294</cik>
                    <ccc>XXXXXXXX</ccc>
                </filerCredentials>
            </filer>
            <liveTestFlag>LIVE</liveTestFlag>



        </filerInfo>
    </headerData>
    <formData>
        <issuerInfo>
            <issuerCik>0001275014</issuerCik>
            <issuerName>ULTRA CLEAN HOLDINGS, INC.</issuerName>
            <secFileNumber>000-50646</secFileNumber>
            <issuerAddress>
                <ns2:street1>26462 Corporate Avenue</ns2:street1>
                <ns2:city>Hayward</ns2:city>
                <ns2:stateOrCountry>CA</ns2:stateOrCountry>
                <ns2:zipCode>94545</ns2:zipCode>
            </issuerAddress>
            <issuerContactPhone>(510) 576-4400</issuerContactPhone>
            <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>JAMES P SCHOLHAMER</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
            <relationshipsToIssuer>
                <relationshipToIssuer>Officer</relationshipToIssuer>
                <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>26608</noOfUnitsSold>
            <aggregateMarketValue>1466100.80</aggregateMarketValue>
            <noOfUnitsOutstanding>44905933</noOfUnitsOutstanding>
            <approxSaleDate>07/09/2024</approxSaleDate>
            <securitiesExchangeName>NASDAQ</securitiesExchangeName>
        </securitiesInformation>
        <securitiesToBeSold>
            <securitiesClassTitle>COMMON</securitiesClassTitle>
            <acquiredDate>02/26/2017</acquiredDate>
            <natureOfAcquisitionTransaction>Restricted Stock</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>ISSUER</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>6633</amountOfSecuritiesAcquired>
            <paymentDate>02/26/2017</paymentDate>
            <natureOfPayment>Not Applicable</natureOfPayment>
        </securitiesToBeSold>
        <securitiesToBeSold>
            <securitiesClassTitle>COMMON</securitiesClassTitle>
            <acquiredDate>01/30/2018</acquiredDate>
            <natureOfAcquisitionTransaction>Restricted Stock</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>ISSUER</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>15773</amountOfSecuritiesAcquired>
            <paymentDate>01/30/2018</paymentDate>
            <natureOfPayment>Not Applicable</natureOfPayment>
        </securitiesToBeSold>
        <securitiesToBeSold>
            <securitiesClassTitle>COMMON</securitiesClassTitle>
            <acquiredDate>04/28/2018</acquiredDate>
            <natureOfAcquisitionTransaction>Restricted Stock</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>ISSUER</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>4202</amountOfSecuritiesAcquired>
            <paymentDate>04/28/2018</paymentDate>
            <natureOfPayment>Not Applicable</natureOfPayment>
        </securitiesToBeSold>
        <nothingToReportFlagOnSecuritiesSoldInPast3Months>Y</nothingToReportFlagOnSecuritiesSoldInPast3Months>
        <noticeSignature>
            <noticeDate>07/09/2024</noticeDate>
            <planAdoptionDates>
                <planAdoptionDate>03/08/2024</planAdoptionDate>
            </planAdoptionDates>
            <signature>/s/ James P Scholhamer</signature>
        </noticeSignature>
    </formData>
</edgarSubmission>
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144
0001133294
XXXXXXXX
LIVE
0001275014
ULTRA CLEAN HOLDINGS, INC.
000-50646
26462 Corporate Avenue
Hayward
CA
94545
(510) 576-4400
JAMES P SCHOLHAMER
Officer
Director
Common
Morgan Stanley Smith Barney LLC Executive Financial Services
1 New York Plaza
8th Floor
New York
NY
10004
26608
1466100.80
44905933
07/09/2024
NASDAQ
COMMON
02/26/2017
Restricted Stock
ISSUER
N
6633
02/26/2017
Not Applicable
COMMON
01/30/2018
Restricted Stock
ISSUER
N
15773
01/30/2018
Not Applicable
COMMON
04/28/2018
Restricted Stock
ISSUER
N
4202
04/28/2018
Not Applicable
Y
07/09/2024
03/08/2024
/s/ James P Scholhamer