<SEC-DOCUMENT>0001014108-18-000004.txt : 20180112
<SEC-HEADER>0001014108-18-000004.hdr.sgml : 20180112
<ACCEPTANCE-DATETIME>20180112112556
ACCESSION NUMBER:		0001014108-18-000004
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20180111
FILED AS OF DATE:		20180112
DATE AS OF CHANGE:		20180112

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			PAULSON THOMAS
		CENTRAL INDEX KEY:			0001217574

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-16191
		FILM NUMBER:		18525120

	MAIL ADDRESS:	
		STREET 1:		5540 PIONEER CREEK DR
		CITY:			MAPLE PLAIN
		STATE:			MN
		ZIP:			55359-9003

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			TENNANT CO
		CENTRAL INDEX KEY:			0000097134
		STANDARD INDUSTRIAL CLASSIFICATION:	REFRIGERATION & SERVICE INDUSTRY MACHINERY [3580]
		IRS NUMBER:				410572550
		STATE OF INCORPORATION:			MN
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		701 N LILAC DR
		STREET 2:		PO BOX 1452
		CITY:			MINNEAPOLIS
		STATE:			MN
		ZIP:			55440
		BUSINESS PHONE:		7635401200

	MAIL ADDRESS:	
		STREET 1:		701 N LILAC DR
		STREET 2:		PO BOX 1452
		CITY:			MINNEAPOLIS
		STATE:			MN
		ZIP:			55440

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	TENNANT G H CO
		DATE OF NAME CHANGE:	19700515
</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>2018-01-11</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000097134</issuerCik>
        <issuerName>TENNANT CO</issuerName>
        <issuerTradingSymbol>TNC</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001217574</rptOwnerCik>
            <rptOwnerName>PAULSON THOMAS</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>TENNANT COMPANY</rptOwnerStreet1>
            <rptOwnerStreet2>701 N. LILAC DRIVE</rptOwnerStreet2>
            <rptOwnerCity>MINNEAPOLIS</rptOwnerCity>
            <rptOwnerState>MN</rptOwnerState>
            <rptOwnerZipCode>55422</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Sr. Vice President and CFO</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2018-01-11</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>6694</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>72.9008</value>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>24035</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1979.79</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>ESOP &amp; Profit Sharing</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">The sale transaction reported on this form is a program transaction to a Rule 10b5-1 plan under the Securities Exchange Act of 1934, as amended.</footnote>
        <footnote id="F2">The price reported in Column 4 is a weighted average price.  These shares were sold in multiple transactions at prices ranging from $72.55 to $73.55, inclusive.  The Reporting Person undertakes to provide to Tennant Company, any security holder of Tennant Company, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/Thomas Paulson</signatureName>
        <signatureDate>2018-01-12</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
