<SEC-DOCUMENT>0000831641-24-000071.txt : 20241120
<SEC-HEADER>0000831641-24-000071.hdr.sgml : 20241120
<ACCEPTANCE-DATETIME>20241120173249
ACCESSION NUMBER:		0000831641-24-000071
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20241118
FILED AS OF DATE:		20241120
DATE AS OF CHANGE:		20241120

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			CARTER BRIAN N
		CENTRAL INDEX KEY:			0001561742
		ORGANIZATION NAME:           	

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-19655
		FILM NUMBER:		241481487

	MAIL ADDRESS:	
		STREET 1:		3475 EAST FOOTHILL BOULEVARD
		CITY:			PASADENA
		STATE:			CA
		ZIP:			91107

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			TETRA TECH INC
		CENTRAL INDEX KEY:			0000831641
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-ENGINEERING SERVICES [8711]
		ORGANIZATION NAME:           	07 Trade & Services
		IRS NUMBER:				954148514
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0929

	BUSINESS ADDRESS:	
		STREET 1:		3475 EAST FOOTHILL BOULEVARD
		CITY:			PASADENA
		STATE:			CA
		ZIP:			91107
		BUSINESS PHONE:		6263514664

	MAIL ADDRESS:	
		STREET 1:		3475 EAST FOOTHILL BOULEVARD
		CITY:			PASADENA
		STATE:			CA
		ZIP:			91107
</SEC-HEADER>
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<TYPE>4
<SEQUENCE>1
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<DESCRIPTION>FORM 4
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    <footnotes>
        <footnote id="F1">On September 6, 2024, the balance of 8,360 shares of common stock was updated pursuant to a 5 to 1 forward stock split, resulting in an additional 33,440 shares of common stock.</footnote>
        <footnote id="F2">Represents the shares underlying restricted stock units (RSUs) withheld to pay the related tax liability.</footnote>
        <footnote id="F3">Represents an award RSUs, each unit of which represents a contingent right to receive one share of Tetra Tech common stock</footnote>
        <footnote id="F4">The RSUs become vested as to 25% of the shares on the first anniversary date, and 25% of the shares on each anniversary date thereafter until fully vested.</footnote>
        <footnote id="F5">The RSUs are exercisable at the time of vesting and do not have a set expiration date.</footnote>
        <footnote id="F6">On September 6, 2024, the balance of 307 shares was updated pursuant to a 5 to 1 forward stock split, resulting in an additional 1,228 shares of common stock.</footnote>
        <footnote id="F7">On September 6, 2024, the balance of 398 shares was updated pursuant to a 5 to 1 forward stock split, resulting in an additional 1,592 shares of common stock.</footnote>
        <footnote id="F8">On September 6, 2024, the balance of 760 shares was updated pursuant to a 5 to 1 forward stock split, resulting in an additional 3,040 shares of common stock.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Preston Hopson, Attorney-in-fact for Brian N. Carter</signatureName>
        <signatureDate>2024-11-20</signatureDate>
    </ownerSignature>
</ownershipDocument>
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</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
