TETRA TECH INC

We provide services to a diverse base of U.S. federal government, U.S. state and local government, U.S. commercial and international clients. The following table presents the percentage of our revenue by client sector:

U.S. federal government agencies are significant clients. The United States Agency for International Development ("USAID") accounted for 10.6%, 13.0% and 12.2% of our revenue in fiscal 2025, 2024 and 2023, respectively. The Department of Defense ("DoD") accounted for 11.6%, 8.5% and 8.9% of our revenue in fiscal 2025, 2024 and 2023, respectively. We typically support multiple programs within a single U.S. federal government agency, both domestically and internationally. We also assist U.S. state and local government clients in various jurisdictions across the United States. Our international clients are primarily focused in Australia, Canada, Europe and the United Kingdom, and consist of a relatively equal sized mix of government and commercial clients. Our U.S. commercial clients include companies in the chemical, energy, technology, retail, aerospace and automotive industries. No single client, except for the U.S. federal government clients, accounted for more than 10% of our revenue in fiscal 2025.