-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 TSltkOUKfQa1biUU1a6EN+7ikL+7kpxxBaSXJ4ZYxXaIV8Xj1VarsLzZZzRxKsef
 alKeir5h8AUcH11CxZ6yFQ==

<SEC-DOCUMENT>0001411284-08-000003.txt : 20080819
<SEC-HEADER>0001411284-08-000003.hdr.sgml : 20080819
<ACCEPTANCE-DATETIME>20080819143646
ACCESSION NUMBER:		0001411284-08-000003
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20080818
FILED AS OF DATE:		20080819
DATE AS OF CHANGE:		20080819

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Clearfield, Inc.
		CENTRAL INDEX KEY:			0000796505
		STANDARD INDUSTRIAL CLASSIFICATION:	OPTICAL INSTRUMENTS & LENSES [3827]
		IRS NUMBER:				411347235
		STATE OF INCORPORATION:			MN
		FISCAL YEAR END:			0930

	BUSINESS ADDRESS:	
		STREET 1:		5480 NATHAN LANE NORTH
		STREET 2:		SUITE 120
		CITY:			PLYMOUTH
		STATE:			MN
		ZIP:			55442
		BUSINESS PHONE:		763-476-6866

	MAIL ADDRESS:	
		STREET 1:		5480 NATHAN LANE NORTH
		STREET 2:		SUITE 120
		CITY:			PLYMOUTH
		STATE:			MN
		ZIP:			55442

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	APA Enterprises, Inc.
		DATE OF NAME CHANGE:	20041116

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	APA OPTICS INC /MN/
		DATE OF NAME CHANGE:	19920703

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Blackey Bruce G.
		CENTRAL INDEX KEY:			0001411284

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-16106
		FILM NUMBER:		081027304

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		763-519-9708

	MAIL ADDRESS:	
		STREET 1:		5480 NATHAN LANE #120
		CITY:			PLYMOUTH
		STATE:			MN
		ZIP:			55442
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2008-08-18</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000796505</issuerCik>
        <issuerName>Clearfield, Inc.</issuerName>
        <issuerTradingSymbol>CLFD</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001411284</rptOwnerCik>
            <rptOwnerName>Blackey Bruce G.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>5480 NATHAN LANE #120</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>PLYMOUTH</rptOwnerCity>
            <rptOwnerState>MN</rptOwnerState>
            <rptOwnerZipCode>55442</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>CFO &amp; Treasurer</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>COMMON STOCK</value>
            </securityTitle>
            <transactionDate>
                <value>2008-08-18</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>400</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>1.2</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2400</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>COMMON STOCK</value>
            </securityTitle>
            <transactionDate>
                <value>2008-08-19</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>600</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>1.19</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>3000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <remarks>SHARES WERE PURCHASED IN MULTIPLE LOTS WITH A WEIGHTED AVERAGE PRICE OF $1.20 WITHIN A PRICE RANGE OF $1.19 AND $1.20.</remarks>

    <ownerSignature>
        <signatureName>BRUCE G. BLACKEY</signatureName>
        <signatureDate>2008-08-19</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----