<SEC-DOCUMENT>0000066740-26-000030.txt : 20260204
<SEC-HEADER>0000066740-26-000030.hdr.sgml : 20260204
<ACCEPTANCE-DATETIME>20260204160734
ACCESSION NUMBER:		0000066740-26-000030
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20260202
FILED AS OF DATE:		20260204
DATE AS OF CHANGE:		20260204

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Rhodes Kevin H
		CENTRAL INDEX KEY:			0001901300
		ORGANIZATION NAME:           	

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-03285
		FILM NUMBER:		26598235

	MAIL ADDRESS:	
		STREET 1:		3M COMPANY
		STREET 2:		3M CENTER, BLDG 220-09-E-02
		CITY:			ST. PAUL
		STATE:			MN
		ZIP:			55144-1000

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			3M CO
		CENTRAL INDEX KEY:			0000066740
		STANDARD INDUSTRIAL CLASSIFICATION:	SURGICAL & MEDICAL INSTRUMENTS & APPARATUS [3841]
		ORGANIZATION NAME:           	08 Industrial Applications and Services
		EIN:				410417775
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		3M CENTER
		STREET 2:		BLDG. 220-9E-02
		CITY:			ST PAUL
		STATE:			MN
		ZIP:			55144-1000
		BUSINESS PHONE:		6517331110

	MAIL ADDRESS:	
		STREET 1:		3M CENTER
		STREET 2:		BLDG. 220-9E-02
		CITY:			ST. PAUL
		STATE:			MN
		ZIP:			55144-1000

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	MINNESOTA MINING & MANUFACTURING CO
		DATE OF NAME CHANGE:	19920703
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>form4.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0508</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2026-02-02</periodOfReport>

    <issuer>
        <issuerCik>0000066740</issuerCik>
        <issuerName>3M CO</issuerName>
        <issuerTradingSymbol>MMM</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001901300</rptOwnerCik>
            <rptOwnerName>Rhodes Kevin H</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>3M CENTER</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>ST. PAUL</rptOwnerCity>
            <rptOwnerState>MN</rptOwnerState>
            <rptOwnerZipCode>55144-1000</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isOfficer>1</isOfficer>
            <officerTitle>EVP, Chief Legal Off &amp; Secret</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <aff10b5One>0</aff10b5One>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2026-02-02</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>23251.392</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>38470.3379</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2026-02-02</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>F</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>4732</value>
                    <footnoteId id="F2"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>33738.3379</value>
                    <footnoteId id="F3"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Represents shares of 3M common stock that will be delivered pursuant to the terms of performance share awards made to the reporting person on March 1, 2023. The performance-based vesting requirements applicable to such awards were satisfied on the date reported in Column 2 above, which represents the date on which the level of performance attained was certified. The reporting person previously elected to defer receipt of fifty percent of the shares and will not have voting or investment powers with respect to such shares until they are issued.</footnote>
        <footnote id="F2">The number of shares withheld for taxes was estimated and will be revised by amendment if necessary.</footnote>
        <footnote id="F3">Includes dividend share equivalents, accrued quarterly, pursuant to 3M's Deferred Compensation Plan.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Patricia L. Meagher, attorney-in-fact for Kevin H. Rhodes</signatureName>
        <signatureDate>2026-02-04</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
