<SEC-DOCUMENT>0001388658-21-000025.txt : 20210203
<SEC-HEADER>0001388658-21-000025.hdr.sgml : 20210203
<ACCEPTANCE-DATETIME>20210203212349
ACCESSION NUMBER:		0001388658-21-000025
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20210112
FILED AS OF DATE:		20210203
DATE AS OF CHANGE:		20210203

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			King Kevin M
		CENTRAL INDEX KEY:			0001385014

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-37918
		FILM NUMBER:		21588524

	MAIL ADDRESS:	
		STREET 1:		C/O AFFYMETRIX, INC.
		STREET 2:		3420 CENTRAL EXPRESSWAY
		CITY:			SANTA CLARA
		STATE:			CA
		ZIP:			95051

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			iRhythm Technologies, Inc.
		CENTRAL INDEX KEY:			0001388658
		STANDARD INDUSTRIAL CLASSIFICATION:	SURGICAL & MEDICAL INSTRUMENTS & APPARATUS [3841]
		IRS NUMBER:				208149544
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		650 TOWNSEND STREET
		STREET 2:		SUITE 500
		CITY:			San Francisco
		STATE:			CA
		ZIP:			94103
		BUSINESS PHONE:		415-632-5700

	MAIL ADDRESS:	
		STREET 1:		650 TOWNSEND STREET
		STREET 2:		SUITE 500
		CITY:			San Francisco
		STATE:			CA
		ZIP:			94103

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	IRhythm Technologies, Inc.
		DATE OF NAME CHANGE:	20110429

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	IRhythm Technologies Inc
		DATE OF NAME CHANGE:	20070201
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wf-form4_161240540727509.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2021-01-12</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001388658</issuerCik>
        <issuerName>iRhythm Technologies, Inc.</issuerName>
        <issuerTradingSymbol>IRTC</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001385014</rptOwnerCik>
            <rptOwnerName>King Kevin M</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O IRHYTHM TECHNOLOGIES, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>699 8TH ST # 600</rptOwnerStreet2>
            <rptOwnerCity>SAN FRANCISCO</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>94103</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2021-01-12</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>7187</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>249288</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">Represents the acquisition of shares in accordance with the terms of a Transition Agreement entered into on January 25, 2021 between the Issuer and the Reporting Person, pursuant to which the vesting of 7,187 performance restricted stock units granted to the Reporting Person on February 26, 2020 was accelerated.</footnote>
        <footnote id="F2">The number of shares beneficially owned following the reported transaction is as of January 12, 2021</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Christina Delfin, attorney in fact</signatureName>
        <signatureDate>2021-02-03</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
