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            <filer>
                <filerCredentials>
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                    <ccc>XXXXXXXX</ccc>
                </filerCredentials>
            </filer>
            <liveTestFlag>LIVE</liveTestFlag>



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    </headerData>
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        <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>SHERI SAVAGE</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>897</noOfUnitsSold>
            <aggregateMarketValue>50115.39</aggregateMarketValue>
            <noOfUnitsOutstanding>44905933</noOfUnitsOutstanding>
            <approxSaleDate>07/11/2024</approxSaleDate>
            <securitiesExchangeName>NASDAQ</securitiesExchangeName>
        </securitiesInformation>
        <securitiesToBeSold>
            <securitiesClassTitle>COMMON</securitiesClassTitle>
            <acquiredDate>03/30/2021</acquiredDate>
            <natureOfAcquisitionTransaction>Restricted Stock</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>ISSUER</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>897</amountOfSecuritiesAcquired>
            <paymentDate>03/30/2021</paymentDate>
            <natureOfPayment>Not Applicable</natureOfPayment>
        </securitiesToBeSold>
        <nothingToReportFlagOnSecuritiesSoldInPast3Months>N</nothingToReportFlagOnSecuritiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>SHERI SAVAGE</name>
                <address>
                    <ns2:street1>26462 Corporate Avenue</ns2:street1>
                    <ns2:city>Hayward</ns2:city>
                    <ns2:stateOrCountry>CA</ns2:stateOrCountry>
                    <ns2:zipCode>94545</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>07/08/2024</saleDate>
            <amountOfSecuritiesSold>10079</amountOfSecuritiesSold>
            <grossProceeds>546080.22</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
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                    <ns2:stateOrCountry>CA</ns2:stateOrCountry>
                    <ns2:zipCode>94545</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>07/02/2024</saleDate>
            <amountOfSecuritiesSold>9682</amountOfSecuritiesSold>
            <grossProceeds>494556.56</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
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                    <ns2:stateOrCountry>CA</ns2:stateOrCountry>
                    <ns2:zipCode>94545</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>06/10/2024</saleDate>
            <amountOfSecuritiesSold>2708</amountOfSecuritiesSold>
            <grossProceeds>127763.44</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
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                    <ns2:stateOrCountry>CA</ns2:stateOrCountry>
                    <ns2:zipCode>94545</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>06/07/2024</saleDate>
            <amountOfSecuritiesSold>1467</amountOfSecuritiesSold>
            <grossProceeds>67349.82</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>SHERI SAVAGE</name>
                <address>
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                    <ns2:city>Hayward</ns2:city>
                    <ns2:stateOrCountry>CA</ns2:stateOrCountry>
                    <ns2:zipCode>94545</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>06/07/2024</saleDate>
            <amountOfSecuritiesSold>1706</amountOfSecuritiesSold>
            <grossProceeds>78484.70</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>SHERI SAVAGE</name>
                <address>
                    <ns2:street1>26462 Corporate Avenue</ns2:street1>
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                    <ns2:stateOrCountry>CA</ns2:stateOrCountry>
                    <ns2:zipCode>94545</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>06/07/2024</saleDate>
            <amountOfSecuritiesSold>1044</amountOfSecuritiesSold>
            <grossProceeds>47907.28</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>SHERI SAVAGE</name>
                <address>
                    <ns2:street1>26462 Corporate Avenue</ns2:street1>
                    <ns2:city>Hayward</ns2:city>
                    <ns2:stateOrCountry>CA</ns2:stateOrCountry>
                    <ns2:zipCode>94545</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>06/07/2024</saleDate>
            <amountOfSecuritiesSold>5551</amountOfSecuritiesSold>
            <grossProceeds>254851.41</grossProceeds>
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        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>SHERI SAVAGE</name>
                <address>
                    <ns2:street1>26462 Corporate Avenue</ns2:street1>
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                    <ns2:zipCode>94545</ns2:zipCode>
                </address>
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            <saleDate>06/07/2024</saleDate>
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            <grossProceeds>256125.36</grossProceeds>
        </securitiesSoldInPast3Months>
        <noticeSignature>
            <noticeDate>07/11/2024</noticeDate>
            <planAdoptionDates>
                <planAdoptionDate>03/08/2024</planAdoptionDate>
            </planAdoptionDates>
            <signature>/s/ Sheri Savage</signature>
        </noticeSignature>
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144
0001667557
XXXXXXXX
LIVE
0001275014
ULTRA CLEAN HOLDINGS, INC.
000-50646
26462 Corporate Avenue
Hayward
CA
94545
(510) 576-4400
SHERI SAVAGE
Officer
Common
Morgan Stanley Smith Barney LLC Executive Financial Services
1 New York Plaza
8th Floor
New York
NY
10004
897
50115.39
44905933
07/11/2024
NASDAQ
COMMON
03/30/2021
Restricted Stock
ISSUER
N
897
03/30/2021
Not Applicable
N
SHERI SAVAGE
26462 Corporate Avenue
Hayward
CA
94545
Common
07/08/2024
10079
546080.22
SHERI SAVAGE
26462 Corporate Avenue
Hayward
CA
94545
Common
07/02/2024
9682
494556.56
SHERI SAVAGE
26462 Corporate Avenue
Hayward
CA
94545
Common
06/10/2024
2708
127763.44
SHERI SAVAGE
26462 Corporate Avenue
Hayward
CA
94545
Common
06/07/2024
1467
67349.82
SHERI SAVAGE
26462 Corporate Avenue
Hayward
CA
94545
Common
06/07/2024
1706
78484.70
SHERI SAVAGE
26462 Corporate Avenue
Hayward
CA
94545
Common
06/07/2024
1044
47907.28
SHERI SAVAGE
26462 Corporate Avenue
Hayward
CA
94545
Common
06/07/2024
5551
254851.41
SHERI SAVAGE
26462 Corporate Avenue
Hayward
CA
94545
Common
06/07/2024
5551
256125.36
07/11/2024
03/08/2024
/s/ Sheri Savage