<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0609</schemaVersion>

    <documentType>4/A</documentType>

    <periodOfReport>2026-08-12</periodOfReport>

    <dateOfOriginalSubmission>2026-08-12</dateOfOriginalSubmission>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001981599</issuerCik>
        <issuerName>Centuri Holdings, Inc.</issuerName>
        <issuerTradingSymbol>CTRI</issuerTradingSymbol>
        <issuerForeignTradingSymbol></issuerForeignTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001673745</rptOwnerCik>
            <rptOwnerName>Youngblood Kelly</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerNonUSAddressFlag>false</rptOwnerNonUSAddressFlag>
            <rptOwnerStreet1>19820 NORTH 7TH AVENUE SUITE 120</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>PHOENIX</rptOwnerCity>
            <rptOwnerState>AZ</rptOwnerState>
            <rptOwnerZipCode>85027</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>See Remarks</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <aff10b5One>0</aff10b5One>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2026-08-12</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>85401</value>
                    <footnoteId id="F1"/>
                    <footnoteId id="F2"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>85401</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">Represents the grant of restricted stock units (&quot;RSUs&quot;) pursuant to the Omnibus Incentive Plan of Centuri Holdings, Inc. (the &quot;Issuer&quot;) on August 12, 2026 (the &quot;2026 RSU Grant&quot;). Each RSU subject to the 2026 RSU Grant is the economic equivalent of one share of the Issuer's common stock and may be settled by delivery of one share of the Issuer's common stock.</footnote>
        <footnote id="F2">This Form 4/A is being filed to amend the Form 4 filed by the Reporting Person on August 12, 2026, solely to correct the number of RSUs previously reported for the grant reported on Table I therein (and the resulting total number of shares of the Issuer's common stock in which the Reporting Person has a pecuniary interest). This Form 4/A does not report any new transactions or otherwise modify any other transaction details that were previously reported.</footnote>
    </footnotes>

    <remarks>The reporting person's full title is Executive Vice President, Chief Financial Officer.</remarks>

    <ownerSignature>
        <signatureName>/s/ Kendra Chilton, as attorney-in-fact for Kelly Youngblood</signatureName>
        <signatureDate>2026-08-19</signatureDate>
    </ownerSignature>
</ownershipDocument>
