<SEC-DOCUMENT>0001179110-13-001618.txt : 20130201
<SEC-HEADER>0001179110-13-001618.hdr.sgml : 20130201
<ACCEPTANCE-DATETIME>20130201140558
ACCESSION NUMBER:		0001179110-13-001618
CONFORMED SUBMISSION TYPE:	4/A
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20090421
FILED AS OF DATE:		20130201
DATE AS OF CHANGE:		20130201

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			FASTENAL CO
		CENTRAL INDEX KEY:			0000815556
		STANDARD INDUSTRIAL CLASSIFICATION:	RETAIL-BUILDING MATERIALS, HARDWARE, GARDEN SUPPLY [5200]
		IRS NUMBER:				410948415
		STATE OF INCORPORATION:			MN
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		2001 THEURER BLVD
		CITY:			WINONA
		STATE:			MN
		ZIP:			55987
		BUSINESS PHONE:		5074545374

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Hein LeLand J
		CENTRAL INDEX KEY:			0001418484

	FILING VALUES:
		FORM TYPE:		4/A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-16125
		FILM NUMBER:		13566085

	MAIL ADDRESS:	
		STREET 1:		2001 THEURER BLVD
		CITY:			WINONA
		STATE:			MN
		ZIP:			55987
</SEC-HEADER>
<DOCUMENT>
<TYPE>4/A
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>FORM 4/A -
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4/A</documentType>

    <periodOfReport>2009-04-21</periodOfReport>

    <dateOfOriginalSubmission>2009-04-30</dateOfOriginalSubmission>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000815556</issuerCik>
        <issuerName>FASTENAL CO</issuerName>
        <issuerTradingSymbol>FAST</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001418484</rptOwnerCik>
            <rptOwnerName>Hein LeLand J</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>2001 THEURER BLVD.</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>WINONA</rptOwnerCity>
            <rptOwnerState>MN</rptOwnerState>
            <rptOwnerZipCode>55987</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>President</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable></nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Employee Stock Option (Right to Buy)</value>
                <footnoteId id="F2"/>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>54</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2009-04-21</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>25000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <value>2018-05-31</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>25000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>25000</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
        <derivativeHolding>
            <securityTitle>
                <value>Employee Stock Option (Right to Buy)</value>
                <footnoteId id="F2"/>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>45</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <value>2016-05-31</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>50000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>50000</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">These options will fully vest and become exercisable over a period of eight years, with 50% of the options vesting and becoming exercisable half way through the vesting period and remainder vesting and becoming exercisable proportionately on each anniversary of the date of grant of the option occuring after the initial vesting date.</footnote>
        <footnote id="F2">Form 4 filed on 4/30/2009 inaccurately combined and did not separately report derivative securities of a differnt class.   This Amended filing is reporting separately the two classes of derivative securities reported in the 4/30/2009 filing and hereby replaces such amounts reported on any subsequent filings.  As of the date of this amended filing (2/1/2013), the reporting person holds 100,000 derivative securites with an exercise price of $22.50 (expiration date of 5/31/2016) and 50,000 derivative securities with an exercise price of $27.00 (expiration date of 5/31/2018) and an additional 37,500 derivative securities that were granted on 4/17/2012 with an exercise price of $54 (expiration date of 5/31/2021), which amounts and exercise prices reflect the stock split in May of 2011.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>John Milek, Attorney-in-Fact</signatureName>
        <signatureDate>2013-02-01</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
