<SEC-DOCUMENT>0001228924-24-000004.txt : 20240403
<SEC-HEADER>0001228924-24-000004.hdr.sgml : 20240403
<ACCEPTANCE-DATETIME>20240403094043
ACCESSION NUMBER:		0001228924-24-000004
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20240402
FILED AS OF DATE:		20240403
DATE AS OF CHANGE:		20240403

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Archbold Brian David
		CENTRAL INDEX KEY:			0001776947
		ORGANIZATION NAME:           	

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-11740
		FILM NUMBER:		24817118

	MAIL ADDRESS:	
		STREET 1:		12100 W. 6TH AVENUE
		CITY:			LAKEWOOD
		STATE:			CO
		ZIP:			80228

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			MESA LABORATORIES INC /CO/
		CENTRAL INDEX KEY:			0000724004
		STANDARD INDUSTRIAL CLASSIFICATION:	INDUSTRIAL INSTRUMENTS FOR MEASUREMENT, DISPLAY, AND CONTROL [3823]
		ORGANIZATION NAME:           	08 Industrial Applications and Services
		IRS NUMBER:				840872291
		STATE OF INCORPORATION:			CO
		FISCAL YEAR END:			0331

	BUSINESS ADDRESS:	
		STREET 1:		12100 W 6TH AVE
		CITY:			LAKEWOOD
		STATE:			CO
		ZIP:			80228
		BUSINESS PHONE:		3039878000

	MAIL ADDRESS:	
		STREET 1:		12100 W 6TH AVE
		CITY:			LAKEWOOD
		STATE:			CO
		ZIP:			80228

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	MESA LABORATORIES INC /CO
		DATE OF NAME CHANGE:	19951117

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	MESA MEDICAL INC
		DATE OF NAME CHANGE:	19921123
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0508</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2024-04-02</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000724004</issuerCik>
        <issuerName>MESA LABORATORIES INC /CO/</issuerName>
        <issuerTradingSymbol>MLAB</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001776947</rptOwnerCik>
            <rptOwnerName>Archbold Brian David</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>12100 W. 6TH AVENUE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>LAKEWOOD</rptOwnerCity>
            <rptOwnerState>CO</rptOwnerState>
            <rptOwnerZipCode>80228</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>SVP Operations</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <aff10b5One>0</aff10b5One>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Non Qualified Stock Option</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>142.4</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2024-04-02</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>E</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>420</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2019-04-02</value>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <value>2024-04-02</value>
                <footnoteId id="F2"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>420</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>14696</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">NSOs that vest 1/5 on each anniversary date of the April 2, 2018 grant date</footnote>
        <footnote id="F2">NSOs expired unexercised on April 2,2024</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>John Sakys under Power of Attorney by Brian Archbold</signatureName>
        <signatureDate>2024-04-03</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
