# EDGAR Filing Document

**Accession Number:** 0000831641
**File Stem:** 0001104659-26-002470
**Filing Date:** 2026-1
**Character Count:** 2210
**Document Hash:** 6e8dc64a29e8728bb3820a601ca2667a
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001104659-26-002470.hdr.sgml**: 20260109

**ACCESSION NUMBER**: 0001104659-26-002470

**CONFORMED SUBMISSION TYPE**: DEFA14A

**PUBLIC DOCUMENT COUNT**: 3

**FILED AS OF DATE**: 20260109

**DATE AS OF CHANGE**: 20260109

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** TETRA TECH INC
- **CENTRAL INDEX KEY:** 0000831641
- **STANDARD INDUSTRIAL CLASSIFICATION:** SERVICES-ENGINEERING SERVICES [8711]
- **ORGANIZATION NAME:** 07 Trade & Services
- **EIN:** 954148514
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 0928

**FILING VALUES:**
- **FORM TYPE:** DEFA14A
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 000-19655
- **FILM NUMBER:** 26523211

**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

**UNITED STATES**

**SECURITIES AND EXCHANGE COMMISSION**

**Washington, D.C. 20549**

**SCHEDULE 14A**

Proxy Statement Pursuant to Section 14(a) of

the Securities Exchange Act of 1934 (Amendment No.)

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| | |
|:---|:---|
| Filed by the Registrant ⌧ | Filed by the Registrant ⌧ |
| Filed by a Party other than the Registrant □ | Filed by a Party other than the Registrant □ |
| Check the appropriate box: | Check the appropriate box: |
| □ | Preliminary Proxy Statement |
| □ | **Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2))** |
| ◻ | Definitive Proxy Statement |
| ⌧ | Definitive Additional Materials |
| □ | Soliciting Material under §240.14a-12 |

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**Tetra Tech, Inc.**

(Name of Registrant as Specified In Its Charter)

**N/A**

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

Payment of Filing Fee (Check the appropriate box):

---

| | |
|:---|:---|
| ⌧ | No fee required. |
| ◻ | Fee paid previously with preliminary materials: |
| ◻ | Fee computed on table in exhibit required by Item 25(b) per Exchange Act Rules 14a6(i)(1) and 0-11. |

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