<SEC-DOCUMENT>0001248915-21-000052.txt : 20210225
<SEC-HEADER>0001248915-21-000052.hdr.sgml : 20210225
<ACCEPTANCE-DATETIME>20210225182256
ACCESSION NUMBER:		0001248915-21-000052
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20210223
FILED AS OF DATE:		20210225
DATE AS OF CHANGE:		20210225

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Grunst Martin E
		CENTRAL INDEX KEY:			0001398210

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-37811
		FILM NUMBER:		21682437

	MAIL ADDRESS:	
		STREET 1:		C/O FREDERIC DORWART, LAWYERS
		STREET 2:		124 EAST FOURTH STREET
		CITY:			TULSA
		STATE:			OK
		ZIP:			74103

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			BOK FINANCIAL CORP
		CENTRAL INDEX KEY:			0000875357
		STANDARD INDUSTRIAL CLASSIFICATION:	NATIONAL COMMERCIAL BANKS [6021]
		IRS NUMBER:				731373454
		STATE OF INCORPORATION:			OK
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		BANK OF OKLAHOMA TOWER
		STREET 2:		BOSTON AVENUE AT SECOND STREET
		CITY:			TULSA
		STATE:			OK
		ZIP:			74172
		BUSINESS PHONE:		9185886000

	MAIL ADDRESS:	
		STREET 1:		BANK OF OKLAHOMA TOWER
		STREET 2:		P O BOX 2300
		CITY:			TULSA
		STATE:			OK
		ZIP:			74192

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	BOK FINANCIAL CORP ET AL
		DATE OF NAME CHANGE:	19950626
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2021-02-23</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000875357</issuerCik>
        <issuerName>BOK FINANCIAL CORP</issuerName>
        <issuerTradingSymbol>BOKF</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001398210</rptOwnerCik>
            <rptOwnerName>Grunst Martin E</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O FREDERIC DORWART, LAWYERS</rptOwnerStreet1>
            <rptOwnerStreet2>124 EAST FOURTH STREET</rptOwnerStreet2>
            <rptOwnerCity>TULSA</rptOwnerCity>
            <rptOwnerState>OK</rptOwnerState>
            <rptOwnerZipCode>74103</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>EVP, Chief Risk Officer</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2021-02-23</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>5667</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>30930</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2021-02-24</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>1711</value>
                    <footnoteId id="F2"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>32641</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2021-02-24</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>F</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>2252</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>90.07</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>30389</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Represents restricted stock which vests on January 8, 2024. Shares are subject to forfeiture (i) upon termination of employment prior to vesting, and (ii) if certain performance earnings per share targets established pursuant to BOKF Executive Incentive Plan are not met.</footnote>
        <footnote id="F2">Represents upward restricted stock adjustments based upon attainment of performance goals established pursuant to the BOKF Executive Incentive Plan for restricted stock awards made in 2018.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Frederic Dorwart, Power of Attorney</signatureName>
        <signatureDate>2021-02-25</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
