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    <periodOfReport>2026-03-03</periodOfReport>

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    <issuer>
        <issuerCik>0001616862</issuerCik>
        <issuerName>Axalta Coating Systems Ltd.</issuerName>
        <issuerTradingSymbol>AXTA</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001476389</rptOwnerCik>
            <rptOwnerName>Bowes Timothy Earl Joseph</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>1050 CONSTITUTION AVENUE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>PHILADELPHIA</rptOwnerCity>
            <rptOwnerState>PA</rptOwnerState>
            <rptOwnerZipCode>19112</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
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            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>President, Glbl Ind. Coatings</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <aff10b5One>0</aff10b5One>

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        <nonDerivativeTransaction>
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            <transactionDate>
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    <derivativeTable>
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            <conversionOrExercisePrice>
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            <transactionDate>
                <value>2026-03-03</value>
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                <equitySwapInvolved>0</equitySwapInvolved>
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            <transactionAmounts>
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                <transactionPricePerShare>
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            <exerciseDate>
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            <expirationDate>
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            <underlyingSecurity>
                <underlyingSecurityTitle>
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                </underlyingSecurityTitle>
                <underlyingSecurityShares>
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                </underlyingSecurityShares>
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            <transactionAmounts>
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                    <value>8070</value>
                </transactionShares>
                <transactionPricePerShare>
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                    <value>Common Shares</value>
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                <underlyingSecurityShares>
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                    <value>D</value>
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                <transactionShares>
                    <value>3500</value>
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                    <value>0</value>
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                    <value>D</value>
                </transactionAcquiredDisposedCode>
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            <exerciseDate>
                <footnoteId id="F9"/>
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                <footnoteId id="F9"/>
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                    <value>Common Shares</value>
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                    <value>3500</value>
                </underlyingSecurityShares>
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                <sharesOwnedFollowingTransaction>
                    <value>7000</value>
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    <footnotes>
        <footnote id="F1">Performance share units convert into common shares on a one-for-one basis.</footnote>
        <footnote id="F2">Shares withheld to satisfy the tax withholding obligation applicable to the vesting of a performance share unit award.</footnote>
        <footnote id="F3">Restricted stock units convert into common shares on a one-for-one basis.</footnote>
        <footnote id="F4">Shares withheld to satisfy the tax withholding obligation applicable to the vesting of a portion of a restricted stock unit award.</footnote>
        <footnote id="F5">Each restricted stock unit represents a contingent right to receive one common share of Axalta Coating Systems Ltd.</footnote>
        <footnote id="F6">This restricted stock unit grant vests in three equal annual installments beginning on the first anniversary of the grant date.</footnote>
        <footnote id="F7">Represents the vesting of a performance share unit award granted on February 28, 2023. The number of common shares issuable under the award may range from zero to 200% of the target number of performance share units (9,060) based upon the Company's achievement of relative total shareholder return during the relevant performance period as described in more detail in the Company's proxy statement filed with the SEC on April 24, 2024. Based upon the Company's achievement of such objective for such period, the performance share unit award vested at 89.07% of target.</footnote>
        <footnote id="F8">Represents the vesting of a performance share unit award granted on February 28, 2023. The number of common shares issuable under the award may range from zero to 200% of the target number of performance share units (9,060) based upon the Company's achievement of Adjusted EBITDA during the relevant performance period as described in more detail in the Company's proxy statement filed with the SEC on April 24, 2024. Based upon the Company's achievement of such objective for such period, the performance share unit award vested at 169.4% of target.</footnote>
        <footnote id="F9">On March 4, 2025, the reporting person was granted 10,500 restricted stock units, vesting in three equal annual installments beginning on March 4, 2026.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Mark Sherman, attorney-in-fact</signatureName>
        <signatureDate>2026-03-05</signatureDate>
    </ownerSignature>
</ownershipDocument>
