<?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>0001648256</cik>
                    <ccc>XXXXXXXX</ccc>
                </filerCredentials>
            </filer>
            <liveTestFlag>LIVE</liveTestFlag>



        </filerInfo>
    </headerData>
    <formData>
        <issuerInfo>
            <issuerCik>0001633978</issuerCik>
            <issuerName>LUMENTUM HOLDINGS INC.</issuerName>
            <secFileNumber>001-36861</secFileNumber>
            <issuerAddress>
                <ns2:street1>1001 Ridder Park Drive</ns2:street1>
                <ns2:city>San Jose</ns2:city>
                <ns2:stateOrCountry>CA</ns2:stateOrCountry>
                <ns2:zipCode>95131</ns2:zipCode>
            </issuerAddress>
            <issuerContactPhone>(408) 546-5483</issuerContactPhone>
            <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>VINCENT D RETORT</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>35153</noOfUnitsSold>
            <aggregateMarketValue>3497371.97</aggregateMarketValue>
            <noOfUnitsOutstanding>68700000</noOfUnitsOutstanding>
            <approxSaleDate>01/22/2025</approxSaleDate>
            <securitiesExchangeName>NASDAQ</securitiesExchangeName>
        </securitiesInformation>
        <securitiesToBeSold>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <acquiredDate>08/15/2020</acquiredDate>
            <natureOfAcquisitionTransaction>Performance Shares</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>ISSUER</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>35153</amountOfSecuritiesAcquired>
            <paymentDate>08/15/2020</paymentDate>
            <natureOfPayment>Not Applicable</natureOfPayment>
        </securitiesToBeSold>
        <nothingToReportFlagOnSecuritiesSoldInPast3Months>N</nothingToReportFlagOnSecuritiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>VINCENT D RETORT</name>
                <address>
                    <ns2:street1>1001 Ridder Park Drive</ns2:street1>
                    <ns2:city>San Jose</ns2:city>
                    <ns2:stateOrCountry>CA</ns2:stateOrCountry>
                    <ns2:zipCode>95131</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>11/25/2024</saleDate>
            <amountOfSecuritiesSold>2553</amountOfSecuritiesSold>
            <grossProceeds>227831.51</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>VINCENT D RETORT</name>
                <address>
                    <ns2:street1>1001 Ridder Park Drive</ns2:street1>
                    <ns2:city>San Jose</ns2:city>
                    <ns2:stateOrCountry>CA</ns2:stateOrCountry>
                    <ns2:zipCode>95131</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>11/25/2024</saleDate>
            <amountOfSecuritiesSold>2640</amountOfSecuritiesSold>
            <grossProceeds>235595.45</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>VINCENT D RETORT</name>
                <address>
                    <ns2:street1>1001 Ridder Park Drive</ns2:street1>
                    <ns2:city>San Jose</ns2:city>
                    <ns2:stateOrCountry>CA</ns2:stateOrCountry>
                    <ns2:zipCode>95131</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>11/25/2024</saleDate>
            <amountOfSecuritiesSold>2070</amountOfSecuritiesSold>
            <grossProceeds>184728.25</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>VINCENT D RETORT</name>
                <address>
                    <ns2:street1>1001 Ridder Park Drive</ns2:street1>
                    <ns2:city>San Jose</ns2:city>
                    <ns2:stateOrCountry>CA</ns2:stateOrCountry>
                    <ns2:zipCode>95131</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>11/25/2024</saleDate>
            <amountOfSecuritiesSold>4314</amountOfSecuritiesSold>
            <grossProceeds>384984.38</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>VINCENT D RETORT</name>
                <address>
                    <ns2:street1>1001 Ridder Park Drive</ns2:street1>
                    <ns2:city>San Jose</ns2:city>
                    <ns2:stateOrCountry>CA</ns2:stateOrCountry>
                    <ns2:zipCode>95131</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>11/25/2024</saleDate>
            <amountOfSecuritiesSold>2359</amountOfSecuritiesSold>
            <grossProceeds>210518.81</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>VINCENT D RETORT</name>
                <address>
                    <ns2:street1>1001 Ridder Park Drive</ns2:street1>
                    <ns2:city>San Jose</ns2:city>
                    <ns2:stateOrCountry>CA</ns2:stateOrCountry>
                    <ns2:zipCode>95131</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>11/25/2024</saleDate>
            <amountOfSecuritiesSold>2474</amountOfSecuritiesSold>
            <grossProceeds>220781.49</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>VINCENT D RETORT</name>
                <address>
                    <ns2:street1>1001 Ridder Park Drive</ns2:street1>
                    <ns2:city>San Jose</ns2:city>
                    <ns2:stateOrCountry>CA</ns2:stateOrCountry>
                    <ns2:zipCode>95131</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>11/25/2024</saleDate>
            <amountOfSecuritiesSold>2474</amountOfSecuritiesSold>
            <grossProceeds>220781.49</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>VINCENT D RETORT</name>
                <address>
                    <ns2:street1>1001 Ridder Park Drive</ns2:street1>
                    <ns2:city>San Jose</ns2:city>
                    <ns2:stateOrCountry>CA</ns2:stateOrCountry>
                    <ns2:zipCode>95131</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>11/25/2024</saleDate>
            <amountOfSecuritiesSold>1906</amountOfSecuritiesSold>
            <grossProceeds>170092.77</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>VINCENT D RETORT</name>
                <address>
                    <ns2:street1>1001 Ridder Park Drive</ns2:street1>
                    <ns2:city>San Jose</ns2:city>
                    <ns2:stateOrCountry>CA</ns2:stateOrCountry>
                    <ns2:zipCode>95131</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>11/25/2024</saleDate>
            <amountOfSecuritiesSold>3971</amountOfSecuritiesSold>
            <grossProceeds>354374.82</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>VINCENT D RETORT</name>
                <address>
                    <ns2:street1>1001 Ridder Park Drive</ns2:street1>
                    <ns2:city>San Jose</ns2:city>
                    <ns2:stateOrCountry>CA</ns2:stateOrCountry>
                    <ns2:zipCode>95131</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>11/25/2024</saleDate>
            <amountOfSecuritiesSold>3655</amountOfSecuritiesSold>
            <grossProceeds>326174.76</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>VINCENT D RETORT</name>
                <address>
                    <ns2:street1>1001 Ridder Park Drive</ns2:street1>
                    <ns2:city>San Jose</ns2:city>
                    <ns2:stateOrCountry>CA</ns2:stateOrCountry>
                    <ns2:zipCode>95131</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>11/25/2024</saleDate>
            <amountOfSecuritiesSold>1122</amountOfSecuritiesSold>
            <grossProceeds>100128.07</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>VINCENT D RETORT</name>
                <address>
                    <ns2:street1>1001 Ridder Park Drive</ns2:street1>
                    <ns2:city>San Jose</ns2:city>
                    <ns2:stateOrCountry>CA</ns2:stateOrCountry>
                    <ns2:zipCode>95131</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>11/25/2024</saleDate>
            <amountOfSecuritiesSold>2420</amountOfSecuritiesSold>
            <grossProceeds>215962.49</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>VINCENT D RETORT</name>
                <address>
                    <ns2:street1>1001 Ridder Park Drive</ns2:street1>
                    <ns2:city>San Jose</ns2:city>
                    <ns2:stateOrCountry>CA</ns2:stateOrCountry>
                    <ns2:zipCode>95131</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>11/25/2024</saleDate>
            <amountOfSecuritiesSold>817</amountOfSecuritiesSold>
            <grossProceeds>72903.77</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>VINCENT D RETORT</name>
                <address>
                    <ns2:street1>1001 Ridder Park Drive</ns2:street1>
                    <ns2:city>San Jose</ns2:city>
                    <ns2:stateOrCountry>CA</ns2:stateOrCountry>
                    <ns2:zipCode>95131</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>11/25/2024</saleDate>
            <amountOfSecuritiesSold>3160</amountOfSecuritiesSold>
            <grossProceeds>281977.86</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>VINCENT D RETORT</name>
                <address>
                    <ns2:street1>1001 Ridder Park Drive</ns2:street1>
                    <ns2:city>San Jose</ns2:city>
                    <ns2:stateOrCountry>CA</ns2:stateOrCountry>
                    <ns2:zipCode>95131</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>11/25/2024</saleDate>
            <amountOfSecuritiesSold>1206</amountOfSecuritiesSold>
            <grossProceeds>107615.60</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>VINCENT D RETORT</name>
                <address>
                    <ns2:street1>1001 Ridder Park Drive</ns2:street1>
                    <ns2:city>San Jose</ns2:city>
                    <ns2:stateOrCountry>CA</ns2:stateOrCountry>
                    <ns2:zipCode>95131</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>11/25/2024</saleDate>
            <amountOfSecuritiesSold>1206</amountOfSecuritiesSold>
            <grossProceeds>107615.60</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>VINCENT D RETORT</name>
                <address>
                    <ns2:street1>1001 Ridder Park Drive</ns2:street1>
                    <ns2:city>San Jose</ns2:city>
                    <ns2:stateOrCountry>CA</ns2:stateOrCountry>
                    <ns2:zipCode>95131</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>11/25/2024</saleDate>
            <amountOfSecuritiesSold>1136</amountOfSecuritiesSold>
            <grossProceeds>101369.26</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>VINCENT D RETORT</name>
                <address>
                    <ns2:street1>1001 Ridder Park Drive</ns2:street1>
                    <ns2:city>San Jose</ns2:city>
                    <ns2:stateOrCountry>CA</ns2:stateOrCountry>
                    <ns2:zipCode>95131</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>11/25/2024</saleDate>
            <amountOfSecuritiesSold>929</amountOfSecuritiesSold>
            <grossProceeds>82897.92</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>VINCENT D RETORT</name>
                <address>
                    <ns2:street1>1001 Ridder Park Drive</ns2:street1>
                    <ns2:city>San Jose</ns2:city>
                    <ns2:stateOrCountry>CA</ns2:stateOrCountry>
                    <ns2:zipCode>95131</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>11/25/2024</saleDate>
            <amountOfSecuritiesSold>1298</amountOfSecuritiesSold>
            <grossProceeds>115834.43</grossProceeds>
        </securitiesSoldInPast3Months>
        <remarks>The securities to be sold were acquired upon the vesting of performance shares during the period of 8/15/2020 through 8/22/2022.</remarks>
        <noticeSignature>
            <noticeDate>01/22/2025</noticeDate>
            <planAdoptionDates>
                <planAdoptionDate>08/26/2024</planAdoptionDate>
            </planAdoptionDates>
            <signature>/s/ Vincent Dominic Retort</signature>
        </noticeSignature>
    </formData>
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144
0001648256
XXXXXXXX
LIVE
0001633978
LUMENTUM HOLDINGS INC.
001-36861
1001 Ridder Park Drive
San Jose
CA
95131
(408) 546-5483
VINCENT D RETORT
Officer
Common
Morgan Stanley Smith Barney LLC Executive Financial Services
1 New York Plaza
8th Floor
New York
NY
10004
35153
3497371.97
68700000
01/22/2025
NASDAQ
Common
08/15/2020
Performance Shares
ISSUER
N
35153
08/15/2020
Not Applicable
N
VINCENT D RETORT
1001 Ridder Park Drive
San Jose
CA
95131
Common
11/25/2024
2553
227831.51
VINCENT D RETORT
1001 Ridder Park Drive
San Jose
CA
95131
Common
11/25/2024
2640
235595.45
VINCENT D RETORT
1001 Ridder Park Drive
San Jose
CA
95131
Common
11/25/2024
2070
184728.25
VINCENT D RETORT
1001 Ridder Park Drive
San Jose
CA
95131
Common
11/25/2024
4314
384984.38
VINCENT D RETORT
1001 Ridder Park Drive
San Jose
CA
95131
Common
11/25/2024
2359
210518.81
VINCENT D RETORT
1001 Ridder Park Drive
San Jose
CA
95131
Common
11/25/2024
2474
220781.49
VINCENT D RETORT
1001 Ridder Park Drive
San Jose
CA
95131
Common
11/25/2024
2474
220781.49
VINCENT D RETORT
1001 Ridder Park Drive
San Jose
CA
95131
Common
11/25/2024
1906
170092.77
VINCENT D RETORT
1001 Ridder Park Drive
San Jose
CA
95131
Common
11/25/2024
3971
354374.82
VINCENT D RETORT
1001 Ridder Park Drive
San Jose
CA
95131
Common
11/25/2024
3655
326174.76
VINCENT D RETORT
1001 Ridder Park Drive
San Jose
CA
95131
Common
11/25/2024
1122
100128.07
VINCENT D RETORT
1001 Ridder Park Drive
San Jose
CA
95131
Common
11/25/2024
2420
215962.49
VINCENT D RETORT
1001 Ridder Park Drive
San Jose
CA
95131
Common
11/25/2024
817
72903.77
VINCENT D RETORT
1001 Ridder Park Drive
San Jose
CA
95131
Common
11/25/2024
3160
281977.86
VINCENT D RETORT
1001 Ridder Park Drive
San Jose
CA
95131
Common
11/25/2024
1206
107615.60
VINCENT D RETORT
1001 Ridder Park Drive
San Jose
CA
95131
Common
11/25/2024
1206
107615.60
VINCENT D RETORT
1001 Ridder Park Drive
San Jose
CA
95131
Common
11/25/2024
1136
101369.26
VINCENT D RETORT
1001 Ridder Park Drive
San Jose
CA
95131
Common
11/25/2024
929
82897.92
VINCENT D RETORT
1001 Ridder Park Drive
San Jose
CA
95131
Common
11/25/2024
1298
115834.43
The securities to be sold were acquired upon the vesting of performance shares during the period of 8/15/2020 through 8/22/2022.
01/22/2025
08/26/2024
/s/ Vincent Dominic Retort