<SEC-DOCUMENT>0001828824-21-000014.txt : 20211104
<SEC-HEADER>0001828824-21-000014.hdr.sgml : 20211104
<ACCEPTANCE-DATETIME>20211104164851
ACCESSION NUMBER:		0001828824-21-000014
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20211102
FILED AS OF DATE:		20211104
DATE AS OF CHANGE:		20211104

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Vig Ravi
		CENTRAL INDEX KEY:			0001828824

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-39675
		FILM NUMBER:		211380698

	MAIL ADDRESS:	
		STREET 1:		C/O ALLEGRO MICROSYSTEMS, INC.
		STREET 2:		955 PERIMETER ROAD
		CITY:			MANCHESTER
		STATE:			NH
		ZIP:			03103

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			ALLEGRO MICROSYSTEMS, INC.
		CENTRAL INDEX KEY:			0000866291
		STANDARD INDUSTRIAL CLASSIFICATION:	SEMICONDUCTORS & RELATED DEVICES [3674]
		IRS NUMBER:				462405937
		FISCAL YEAR END:			0325

	BUSINESS ADDRESS:	
		STREET 1:		955 PERIMETER ROAD
		CITY:			MANCHESTER
		STATE:			NH
		ZIP:			03103
		BUSINESS PHONE:		(603) 626-2300

	MAIL ADDRESS:	
		STREET 1:		955 PERIMETER ROAD
		CITY:			MANCHESTER
		STATE:			NH
		ZIP:			03103

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	ALLEGRO MICROSYSTEMS INC
		DATE OF NAME CHANGE:	19900730
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wf-form4_163605880415038.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2021-11-02</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000866291</issuerCik>
        <issuerName>ALLEGRO MICROSYSTEMS, INC.</issuerName>
        <issuerTradingSymbol>ALGM</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001828824</rptOwnerCik>
            <rptOwnerName>Vig Ravi</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>955 PERIMETER ROAD</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>MANCHESTER</rptOwnerCity>
            <rptOwnerState>NH</rptOwnerState>
            <rptOwnerZipCode>03103</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>President and CEO</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2021-11-02</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>41993</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>31.25</value>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                    <footnoteId id="F1"/>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1573811</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2021-11-03</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>48007</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>31.61</value>
                    <footnoteId id="F3"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                    <footnoteId id="F1"/>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1525804</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2021-11-02</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>41943</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>31.25</value>
                    <footnoteId id="F5"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                    <footnoteId id="F4"/>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>311147</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Trust for Child 1</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2021-11-03</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>18057</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>31.29</value>
                    <footnoteId id="F6"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                    <footnoteId id="F4"/>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>293090</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Trust for Child 1</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2021-11-02</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>41870</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>31.25</value>
                    <footnoteId id="F7"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                    <footnoteId id="F4"/>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>311220</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Trust for Child 2</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2021-11-03</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>18130</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>31.29</value>
                    <footnoteId id="F8"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                    <footnoteId id="F4"/>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>293090</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Trust for Child 2</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2021-11-02</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>41968</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>31.25</value>
                    <footnoteId id="F9"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                    <footnoteId id="F4"/>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>311122</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Trust for Child 3</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2021-11-03</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>18032</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>31.29</value>
                    <footnoteId id="F10"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                    <footnoteId id="F4"/>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>293090</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Trust for Child 3</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on September 2, 2021.</footnote>
        <footnote id="F2">The reported transaction involves sale transactions ranging from $30.84 to $31.52 per share. The weighted average price per share was $31.25. The Reporting Person undertakes to provide upon request by the SEC staff, the Issuer or a security holder of the Issuer, information regarding the number of shares sold at each separate price.</footnote>
        <footnote id="F3">The reported transaction involves sale transactions ranging from $30.77 to $31.94 per share. The weighted average price per share was $31.61. The Reporting Person undertakes to provide upon request by the SEC staff, the Issuer or a security holder of the Issuer, information regarding the number of shares sold at each separate price.</footnote>
        <footnote id="F4">The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on September 3, 2021.</footnote>
        <footnote id="F5">The reported transaction involves sale transactions ranging from $30.91 to $31.52 per share. The weighted average price per share was $31.25. The Reporting Person undertakes to provide upon request by the SEC staff, the Issuer or a security holder of the Issuer, information regarding the number of shares sold at each separate price.</footnote>
        <footnote id="F6">The reported transaction involves sale transactions ranging from $30.77 to $31.64 per share. The weighted average price per share was $31.29. The Reporting Person undertakes to provide upon request by the SEC staff, the Issuer or a security holder of the Issuer, information regarding the number of shares sold at each separate price.</footnote>
        <footnote id="F7">The reported transaction involves sale transactions ranging from $30.84 to $31.53 per share. The weighted average price per share was $31.25. The Reporting Person undertakes to provide upon request by the SEC staff, the Issuer or a security holder of the Issuer, information regarding the number of shares sold at each separate price.</footnote>
        <footnote id="F8">The reported transaction involves sale transactions ranging from $30.78 to $31.60 per share. The weighted average price per share was $31.29. The Reporting Person undertakes to provide upon request by the SEC staff, the Issuer or a security holder of the Issuer, information regarding the number of shares sold at each separate price.</footnote>
        <footnote id="F9">The reported transaction involves sale transactions ranging from $30.86 to $31.52 per share. The weighted average price per share was $31.25. The Reporting Person undertakes to provide upon request by the SEC staff, the Issuer or a security holder of the Issuer, information regarding the number of shares sold at each separate price.</footnote>
        <footnote id="F10">The reported transaction involves sale transactions ranging from $30.76 to $31.64 per share. The weighted average price per share was $31.29. The Reporting Person undertakes to provide upon request by the SEC staff, the Issuer or a security holder of the Issuer, information regarding the number of shares sold at each separate price.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Christopher E. Brown, Attorney-in-Fact for Ravi Vig</signatureName>
        <signatureDate>2021-11-04</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
