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

    <schemaVersion>X0407</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2023-07-10</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000783325</issuerCik>
        <issuerName>WEC ENERGY GROUP, INC.</issuerName>
        <issuerTradingSymbol>WEC</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001558300</rptOwnerCik>
            <rptOwnerName>Lane Thomas K</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>231 WEST MICHIGAN STREET</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>MILWAUKEE</rptOwnerCity>
            <rptOwnerState>WI</rptOwnerState>
            <rptOwnerZipCode>53203</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <aff10b5One>0</aff10b5One>

    <nonDerivativeTable></nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Phantom Stock Units</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F1"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2023-07-10</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>452.3352</value>
                    <footnoteId id="F2"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>88.43</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F3"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F3"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>452.3352</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>6866.7367</value>
                    <footnoteId id="F4"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">One-for-one.</footnote>
        <footnote id="F2">These phantom stock units were acquired pursuant to a deferral of director fees in an acquisition exempt from Section 16(b) pursuant to Rule 16b-3(d).</footnote>
        <footnote id="F3">These phantom stock units were accrued under the WEC Energy Group, Inc. Director's Deferred Compensation Plan (DDCP) and are to be settled in accordance with the terms of the plan.</footnote>
        <footnote id="F4">Includes phantom stock units accrued pursuant to a dividend reinvestment feature of the DDCP in transactions exempt from Section 16 pursuant to Rule 16a-11.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Joshua M. Erickson, as attorney in fact</signatureName>
        <signatureDate>2023-07-12</signatureDate>
    </ownerSignature>
</ownershipDocument>
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X0407
4
2023-07-10
0
0000783325
WEC ENERGY GROUP, INC.
WEC
0001558300
Lane Thomas K
231 WEST MICHIGAN STREET
MILWAUKEE
WI
53203
1
0
0
0
0
Phantom Stock Units
2023-07-10
4
A
0
452.3352
88.43
A
Common Stock
452.3352
6866.7367
D
One-for-one.
These phantom stock units were acquired pursuant to a deferral of director fees in an acquisition exempt from Section 16(b) pursuant to Rule 16b-3(d).
These phantom stock units were accrued under the WEC Energy Group, Inc. Director's Deferred Compensation Plan (DDCP) and are to be settled in accordance with the terms of the plan.
Includes phantom stock units accrued pursuant to a dividend reinvestment feature of the DDCP in transactions exempt from Section 16 pursuant to Rule 16a-11.
Joshua M. Erickson, as attorney in fact
2023-07-12