<SEC-DOCUMENT>0000913760-21-000233.txt : 20211217
<SEC-HEADER>0000913760-21-000233.hdr.sgml : 20211217
<ACCEPTANCE-DATETIME>20211217171932
ACCESSION NUMBER:		0000913760-21-000233
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20211215
FILED AS OF DATE:		20211217
DATE AS OF CHANGE:		20211217

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Perkins Abigail H
		CENTRAL INDEX KEY:			0001862195

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-36045
		FILM NUMBER:		211502683

	MAIL ADDRESS:	
		STREET 1:		230 PARK AVENUE
		STREET 2:		10TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10169

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			StoneX Group Inc.
		CENTRAL INDEX KEY:			0000913760
		STANDARD INDUSTRIAL CLASSIFICATION:	SECURITY & COMMODITY BROKERS, DEALERS, EXCHANGES & SERVICES [6200]
		IRS NUMBER:				592921318
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0930

	BUSINESS ADDRESS:	
		STREET 1:		230 PARK AVE
		STREET 2:		10TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10169
		BUSINESS PHONE:		212-485-3500

	MAIL ADDRESS:	
		STREET 1:		230 PARK AVE
		STREET 2:		10TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10169

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	INTL FCSTONE INC.
		DATE OF NAME CHANGE:	20110302

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	INTERNATIONAL ASSETS HOLDING CORP
		DATE OF NAME CHANGE:	19931020
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wf-form4_163977955204160.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2021-12-15</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000913760</issuerCik>
        <issuerName>StoneX Group Inc.</issuerName>
        <issuerTradingSymbol>SNEX</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001862195</rptOwnerCik>
            <rptOwnerName>Perkins Abigail H</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>230 PARK AVENUE</rptOwnerStreet1>
            <rptOwnerStreet2>10TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10169</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chief Information Officer</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Restricted Shares of Common Stock</value>
                <footnoteId id="F1"/>
            </securityTitle>
            <transactionDate>
                <value>2021-12-15</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>1353</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2153</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Options</value>
                <footnoteId id="F2"/>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>62.04</value>
                <footnoteId id="F3"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2021-12-15</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>30000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>62.04</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2022-12-05</value>
                <footnoteId id="F4"/>
            </exerciseDate>
            <expirationDate>
                <value>2026-12-05</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>30000.0</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>30000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Shares issued pursuant to the terms of the Company's Executive Performance Plan. Shares vest equally on anniversary in years one, two and three.</footnote>
        <footnote id="F2">The option grant was approved by the Company's Board of Directors on December 15, 2021.</footnote>
        <footnote id="F3">The strike price of the grant was set by the Company's Board of Directors as the closing price on December 14, 2021.</footnote>
        <footnote id="F4">The options vest in equal tranches on each of the first, second, third and fourth anniversaries of the Exercisable Date.  The Exercisable Date and Expiration Date were set by the Company's Board of Directors to coincide with the same dates as stock options previously granted to additional members of the Company's senior executive management team.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Abigail H. Perkins</signatureName>
        <signatureDate>2021-12-17</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
