<SEC-DOCUMENT>0001600424-25-000007.txt : 20251128
<SEC-HEADER>0001600424-25-000007.hdr.sgml : 20251128
<ACCEPTANCE-DATETIME>20251128164815
ACCESSION NUMBER:		0001600424-25-000007
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20251125
FILED AS OF DATE:		20251128
DATE AS OF CHANGE:		20251128

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Mihm Oliver K.
		CENTRAL INDEX KEY:			0001600424
		ORGANIZATION NAME:           	

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-14423
		FILM NUMBER:		251536273

	MAIL ADDRESS:	
		STREET 1:		ONE PLEXUS WAY
		CITY:			NEENAH
		STATE:			X1
		ZIP:			54956

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			PLEXUS CORP
		CENTRAL INDEX KEY:			0000785786
		STANDARD INDUSTRIAL CLASSIFICATION:	PRINTED CIRCUIT BOARDS [3672]
		ORGANIZATION NAME:           	04 Manufacturing
		EIN:				391344447
		STATE OF INCORPORATION:			WI
		FISCAL YEAR END:			0927

	BUSINESS ADDRESS:	
		STREET 1:		PLEXUS CORP
		STREET 2:		ONE PLEXUS WAY
		CITY:			NEENAH
		STATE:			WI
		ZIP:			54956
		BUSINESS PHONE:		9209696000

	MAIL ADDRESS:	
		STREET 1:		PLEXUS CORP
		STREET 2:		ONE PLEXUS WAY
		CITY:			NEENAH
		STATE:			WI
		ZIP:			54956
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wk-form4_1764366492.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0508</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2025-11-25</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000785786</issuerCik>
        <issuerName>PLEXUS CORP</issuerName>
        <issuerTradingSymbol>PLXS</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001600424</rptOwnerCik>
            <rptOwnerName>Mihm Oliver K.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>ONE PLEXUS WAY</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>NEENAH</rptOwnerCity>
            <rptOwnerState>WI</rptOwnerState>
            <rptOwnerZipCode>54956</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Exec VP &amp; COO</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <aff10b5One>0</aff10b5One>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock, $.01 par value</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>981</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>401(k)</value>
                    <footnoteId id="F1"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock, $.01 par value</value>
            </securityTitle>
            <transactionDate>
                <value>2025-11-25</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>2327</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>143.18</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>18442</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">Shares of Plexus Corp. common stock held in the Plexus Corp. 401(k) Retirement Plan as of the last report from the Plan's trustee.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Oliver K. Mihm, by Kate A. Gitter, Attorney-in-Fact</signatureName>
        <signatureDate>2025-11-28</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
