DEF 14A of Tetra Tech Inc, Jan 9, 2026

DEF 14A of Tetra Tech Inc

Filed Jan 9, 2026 · FY20250001104659-26-002458

Open on EDGAR

  1. Tetra Tech

    Tetra Tech Tetra Tech is a leading global provider of high-end consulting and engineering services that focuses on water, environment and sustainable infrastructure. We are a global company that is Leading with Science to provide innovative solutions for our public and private clients. We typically begin at the earliest stage of a project by identifying technical solutions and developing execution plans tailored to our clients’ needs and resources. Engineering News-Record (ENR), the engineering industry’s leading magazine, has ranked Tetra Tech #1 in water treatment for 12 years in a row. In 2025, we were also ranked #1 in consulting studies, environmental management, environmental science, wind power, hydro plants, site assessment and compliance, and green government offices. ENR also ranked Tetra Tech in the top 10 in numerous categories, including dams and reservoirs, marine and port facilities, power, solar power, solid waste, chemical and soil remediation, and hazardous waste. Our reputation for high-end consulting and engineering services and our ability to develop innovative, sustainable solutions for water and environmental management have supported our growth for nearly 60 years. Today, we are proud to be making a difference in people’s lives worldwide through our high-end consulting, engineering, and technology service offerings. In fiscal year (FY) 2025— with a talent force of more than 25,000 employees—we worked on more than 110,000 projects in over 100 countries on all seven continents. We are Leading with Science throughout our operations, with domain experts across multiple disciplines supported by our advanced analytics, artificial intelligence (AI), machine learning, and digital technology solutions. Our ability to provide innovation and first-of-a-kind solutions is enhanced by partnerships with our forward-thinking clients. We embrace the breadth of experience across our talented workforce worldwide with a culture of innovation and entrepreneurship. We are disciplined in our business and focused on delivering value to customers and high performance for our stockholders. In supporting our clients, we seek to add value and provide long-term sustainable consulting, engineering, and technology solutions.

  2. FY 2025 Components of Annual and Long-Term Compensation

    FY 2025 Components of Annual and Long-Term Compensation

  3. Compensation Best Practices

    | What We Do | | | | | | Focus on pay for performance: In FY 2025, 89% of our Chief Executive Officer’s (CEO’s) target total direct compensation (TDC) and an average of 74% of our other named executive officers’ (NEOs’) target TDC was at-risk | | Review the Compensation Committee’s charter, and evaluate the Compensation Committee’s performance | | | Emphasize long-term performance: In FY 2025, 72% of our CEO’s target TDC and an average of 50% of our other NEOs’ target TDC was equity based and, thereby, tied to creating stockholder value | | Use an independent compensation consultant retained directly by the Compensation Committee | | | Require double trigger for change in control equity vesting and cash severance benefits | | Assess potential risks relating to our compensation policies and practices | | | Maintain stock ownership guidelines for both executives and the Board of Directors | | Maintain a clawback policy |

  4. Compensation Best Practices

    | What We Do Not Do | | | | | | Have employment agreements with our NEOs | | Grant stock options with an exercise price less than the fair market value on the date of grant | | | Provide excise tax gross up payments in connection with change in control severance benefits | | Reprice or exchange stock options | | | Provide gross ups to cover tax liabilities associated with executive perquisites | | Promise multiyear guarantees for bonus payouts or salary increases | | | Permit directors, officers, or employees to hedge or pledge Company stock | | Pay dividends or dividend equivalents on equity awards unless and until the awards vest |

  5. Standing Committees of the Board of Directors

    | Compensation Committee | | | Meetings in FY 2025: 4 | Average Attendance in FY 2025: 100% | | Chair Kirsten M. Volpi Members Jeffrey R. Feeler Prashant Gandhi Christiana Obiaya Kimberly E. Ritrievi All members satisfy the independence standards required by Nasdaq. All members qualify as “nonemployee directors” under Rule 16b-3 of the Exchange Act. | Responsibilities • Review and approve the annual base salaries and annual incentive opportunities of the CEO and other executive officers, including an evaluation of the performance of the executive officers in light of our performance goals and objectives • Review and approve all other incentive awards and opportunities, any employment agreements and severance arrangements, any change in control agreements, and any special or supplemental compensation and benefits as they affect the executive officers • Review and discuss comments provided by stockholders and proxy advisory firms regarding our executive compensation • Monitor compliance with requirements under the Sarbanes Oxley Act of 2002 relating to loans to director and executive officers, and with all other applicable laws affecting employee compensation and benefits • Oversee our compliance with SEC rules and regulations regarding stockholder approval of certain executive compensation matters • Review director and executive officer stock ownership under our stock ownership guidelines • Make recommendations to the Board on changes in the compensation of nonemployee directors • Review and discuss incentives and rewards in accordance with our ERM responsibility matrix • Make recommendations to the Board with respect to incentive-based compensation plans, equity-based plans, and executive benefits • Review and approve all grants of equity awards • Review and discuss the annual Compensation Discussion and Analysis and Compensation Committee Report to be included in the proxy statement • Select, retain and work with the independent compensation consultant |

  6. Selection of Director Nominees

    Selection of Director Nominees Director nominees are generally recommended to the Board by the NCG Committee for election to the Board. Our Board believes that the backgrounds and qualifications of our directors, considered as a group, provide a mix of complementary experience, knowledge, and abilities that enables our directors to effectively fulfill their oversight responsibilities. In considering whether to recommend a candidate as a director nominee, the NCG Committee applies the criteria described in our governance policies, including independence, integrity, high personal and professional ethics, sound business judgment, and the ability and willingness to commit sufficient time to the Board. In evaluating the suitability of individual Board members, the NCG Committee takes into account many factors, including a general understanding of business development and strategy, risk management, finance, financial reporting, and other disciplines relevant to the success of a publicly traded company in the then current business environment; understanding of our business and the issues affecting it; relevant education and professional background; and personal accomplishment. The NCG committee does not have a formal policy specifying how diversity of background and personal experience should be applied in identifying or evaluating director candidates, and a candidate’s background and personal experience, while important, does not necessarily outweigh other attributes or factors the NCG Committee considers in evaluating candidates. The NCG Committee does not assign specific weights to the criteria, and no particular criterion is necessarily applicable to all nominees. In recommending candidates for election to the Board of Directors, the NCG Committee considers nominees recommended by directors, officers, stockholders, and others using the same criteria to evaluate all candidates. The NCG Committee reviews each candidate’s qualifications, including whether the candidate possesses any of the specific qualities and skills desirable in members of the Board of Directors. Evaluations of candidates generally involve a review of background information, internal discussions, and interviews with selected candidates as appropriate. Upon selection of a qualified candidate, the NCG Committee recommends the candidate for consideration by the full Board. The Committee may engage consultants or third-party search firms to assist in identifying and evaluating potential nominees.

  7. Item 1: Election of Directors

    Item 1: Election of Directors Our bylaws provide for a board of between five and 10 directors, with the exact number fixed from time to time by a resolution of our Board. The Board currently has fixed the number at eight directors. At the time of the Annual Meeting, the number of directors will be fixed at six directors. Each of the director nominees is currently a member of our Board of Directors and, other than Mr. Feeler and Ms. Hardwick who joined our Board in December 2025, was elected to our Board of Directors at the 2025 Annual Meeting. Mr. Feeler and Ms. Hardwick are standing for election to the Board of Directors for the first time. Each of them was initially identified to the Board of Directors as a potential director nominee by professional search firms. The NCG Committee then assessed the potential candidacy of Mr. Feeler and Ms. Hardwick in light of the director criteria included in our Corporate Governance Policies. Each member of the Board of Directors interviewed Mr. Feeler and Ms. Hardwick. Following these interviews, the Board of Directors then met, discussed and approved the appointments of Mr. Feeler and Ms. Hardwick to the Board. Each director elected at the 2026 Annual Meeting will serve until our 2027 Annual Meeting and until their respective successors are duly elected and qualified or until his or her resignation or removal. Each of the nominees has consented to being named in this proxy statement and to continue serving if elected. If any nominee is unable or unwilling to stand for election or serve as a director if elected, the persons named as proxies may vote for a substitute nominee designated by our existing Board of Directors, or our Board may choose to reduce its size.

  8. 2026 Director Nominees

    2026 Director Nominees This section provides information on each nominee for the Board of Directors for election at the 2026 Annual Meeting, including their age, Board leadership roles held, and business experience during at least the past five years. We also indicate the name of any other public company for which each nominee currently serves as a director or served as a director during the past five years. The information on each nominee led our Board to the conclusion that they should serve as a director in light of the Company’s business and structure. We believe that each of these nominees has integrity and adheres to our high ethical standards. In addition, each nominee has demonstrated the ability to exercise sound judgment as well as a commitment to serving the long-term interests of our stockholders.

  9. 2026 Director Nominees

    | Dan L. Batrack | | Chairman and CEO | Director since 2005 | | | | Experience • CEO and director since 2005; Chairman since 2008; President from 2008 to 2019 and from May 2024 to October 2025. • Joined Tetra Tech in 1980 and has served in numerous capacities, including arctic research scientist, deepwater oceanographic hydrographer, coastal hydrodynamic modeler, environmental data analyst, project and program manager, and President of the Engineering Division, and, in 2004, was appointed Chief Operating Officer • Established the firm’s strategic direction and focus on Leading with Science® to become the premier global consulting firm focused on water, environment, and sustainable infrastructure • Led research and engineering programs in locations in the Arctic and throughout South America, the Middle East, and the United States • Serves as corporate sponsor for several of our clients’ programs and remains engaged in our day-to-day operations Skills and Qualifications Senior leadership; industry and technical experience; government client regulatory experience; business development and M&A; financial sophistication; innovation/technology; international operations; risk oversight; talent management/compensation. • BA, Business Administration, University of Washington | | | Age | 67 | | |

  10. 2026 Director Nominees

    | Gary R. Birkenbeuel | | Independent | Director since 2018 | | | | Experience • Retired after 37 years with Ernst & Young LLP (E&Y) • Former Regional Assurance Managing Partner, E&Y, 2003-2017 • Served as the audit partner in charge of multinational publicly and privately held companies engaged in the aerospace and defense, entertainment, technology, and media industries Skills and Qualifications Senior leadership; financial sophistication; audit committee financial expert; certified public accountant; risk oversight; talent management/compensation. • Director and chairman of the investment and audit committees, American Film Institute • BA, Economics, Claremont McKenna College | | | Age | 68 | | | | Current Committees: | Chair, Audit; Member, NCG | | |

  11. 2026 Director Nominees

    | Jeffrey R. Feeler | | Independent | Director since 2025 | | | | Experience • Chairman and CEO of US Ecology, 2013-2022; COO and Interim CEO, 2012-2013; CFO, 2007-2012; Treasurer and CAO, 2006-2007 • Manager, Financial Reporting, MWI Veterinary Supply, Inc., 2005-2006 • Director, Financial Reporting, Albertsons, Inc., 2003-2005 Skills and Qualifications Senior leadership; industry and technical experience; business development and M&A; financial sophistication; audit committee financial expert; certified public accountant; innovation/ technology; risk oversight; talent management/compensation. • Director, Milestone Environmental; BTS Bioenergy • BBA, Accounting and Finance, Boise State University | | | Age | 56 | | | | Current Committees: | Member, Audit; Member, Compensation | | |

  12. 2026 Director Nominees

    | Prashant Gandhi | | Independent | Director since 2022 | | | | Experience • Chief Business Officer of Melio Payments since 2021 • Head of Digital Payments, JP Morgan Chase, 2017-2021 • Partner and Global Chief Operating Officer, Digital Practice, McKinsey & Company, 2000-2016 Skills and Qualifications Senior leadership; business development and M&A; financial sophistication; innovation/ technology; international operations; risk oversight; talent management/compensation. • Advisory Board member, University of Minnesota’s School of Information & Decision Sciences • BS, Chemical Engineering, Indian Institute of Technology Delhi • MS, Chemical Engineering, Kansas State University • MBA, University of Chicago’s Booth School of Business | | | Age | 54 | | | | Current Committees: | Chair, NCG; Member, Compensation | | |

  13. 2026 Director Nominees

    | M. Susan Hardwick | | Independent | Director since 2025 | | | | Experience • CEO of American Water, 2022-2024; CFO, 2019-2022 • CFO, Vectren Corporation, 2014-2019; SVP, Finance, 2013-2014; Controller, 2000-2013 • Assistant Corporate Controller, Cinergy Corp., 1992-1999 Skills and Qualifications Senior leadership; government client regulatory experience; business development and M&A; financial sophistication; audit committee financial expert; certified public accountant; innovation/ technology; risk oversight; talent management/compensation. • BS, Accounting, Indiana University Bloomington | | | Age | 63 | | | | Current Committees: | Member, Audit; Member, NCG | | | | Other Current Public Boards: | New Jersey Resources Corporation | | |

  14. 2026 Director Nominees

    | Kirsten M. Volpi | | Independent, Presiding Director | Director since 2013 | | | | Experience • EVP, COO, CFO, and Treasurer Colorado School of Mines, since 2013; Senior Vice President for Finance and Administration, CFO, and Treasurer, 2005-2011 • Chief Administrative Officer, U.S. Olympic Committee, 2011-2013 • Various financial management roles for Rensselaer Polytechnic Institute, University of Colorado Foundation, and American Water Works Association Skills and Qualifications Senior leadership; financial sophistication; audit committee financial expert; certified public accountant; international operations; risk oversight; talent management/compensation. • BS, Accounting, University of Colorado | | | Age | 61 | | | | Current Committees: | Member, Audit; Chair, Compensation | | |

  15. Director Compensation

    Director Compensation The Compensation Committee works with the independent compensation consultant, Meridian Compensation Partners, LLC (Meridian), to target nonemployee director compensation within a competitive range of the median of our peer companies to support the recruitment and retention of our nonemployee directors. The majority of each director’s compensation is delivered in equity to align director interests with those of our stockholders. Under our stock ownership guidelines, each nonemployee director must own shares having a value equal to at least five times the nonemployee director’s annual base cash retainer. Directors have five years from the date of their election to the Board to attain the required level of stock ownership.

  16. FY 2025 Equity Compensation

    FY 2025 Equity Compensation During FY 2025, our nonemployee director equity compensation program consisted of an equity award based on a fixed dollar value of $175,000. The following table describes the awards granted on November 20, 2024.

  17. PSU and RSU Awards Granted

    PSU and RSU Awards Granted

  18. PSU and RSU Awards Granted

    | Type of Award | Shares Underlying Award (#) | Description | | Performance Stock Units (PSUs) | 2,577 | Represents target shares underlying the award. PSUs have a three-year performance period with cliff vesting on the applicable vesting date and with the same terms as the PSUs awarded to our executive officers, subject to the achievement of the applicable performance goals. PSUs vest immediately upon change in control or upon departure from the Board after serving 10 years or more, having served the full term for which the director was elected, and subject to achievement of the applicable performance criteria. Upon the director’s departure having served less than 10 years or upon death or disability, PSUs vest on a pro rata basis on the scheduled vesting date and subject to achievement of the applicable performance criteria. For additional information concerning PSU vesting, refer to the Compensation Discussion and Analysis section of this proxy statement. |

  19. PSU and RSU Awards Granted

    | Type of Award | Shares Underlying Award (#) | Description | | Restricted Stock Units (RSUs) | 1,718 | Vested on November 30, 2025, if the director had not ceased to be a director prior to that date. RSUs vest immediately upon change in control or upon departure from the Board after serving 10 years or more and having served the full term for which the director was elected. Upon the director’s departure having served less than 10 years, RSUs vest on a pro rata basis. Upon the director’s death or disability, unvested RSUs are forfeited. |

  20. Director Compensation Table

    Director Compensation Table The following table provides information concerning the compensation for services of our nonemployee directors during FY 2025.

  21. Direct Compensation by Director

    | Name1 | Fees Earned or Paid in Cash ($) | Option Awards ($)2 | Stock Awards ($)3 | Total ($) | | Mr. Birkenbeuel | 130,000 | 0 | 173,286 | 303,286 | | Mr. Gandhi | 125,000 | 0 | 173,286 | 298,286 | | Ms. Obiaya | 115,000 | 0 | 173,286 | 288,286 | | Dr. Ritrievi | 120,000 | 0 | 173,286 | 293,286 | | Ms. Volpi | 168,000 | 0 | 173,286 | 341,286 |

  22. Direct Compensation by Director

    1 Mr. Batrack does not appear in the table because he received compensation as our CEO and does not receive any additional compensation as director. Mr. Feeler and Ms. Hardwick do not appear in the table because they joined the Board in December 2025, following the completion of FY 2025. 2 No stock options were granted to nonemployee directors in FY 2025. For information regarding the number of stock options held by each nonemployee director as of September 28, 2025, see the Stock Options Outstanding (#) column in the Nonqualified Stock Options, Unvested PSUs, and Unvested RSUs by Director table below. 3 $104,189 of the amounts in the Stock Awards column represent the aggregate grant date fair values, without adjustment for forfeitures, of PSUs that are payable at the end of a three-year performance period provided that the performance objectives are achieved as of the end of the period. The actual number of shares issued can range from 0% to 200% of the target shares at the time of grant. The performance objectives that determine the number of shares that may be earned for the PSUs were (i) as to 50% of the award, growth in earnings per share, which is a performance condition under FASB ASC Topic 718, and (ii) as to 50% of the award, total stockholder return (TSR), which is a market condition under FASB ASC Topic 718, relative to the S&P 400, in each case computed over the three-year performance period. The performance condition component of the fair value of PSUs was determined based on the fair market value of our common stock on the date of grant. The market condition component of the fair value of the PSUs was determined as of the date of grant using the Monte Carlo simulation method, which uses multiple input variables to estimate the probability of meeting the performance objectives established for the award, including the expected volatility of our stock price and other assumptions appropriate for determining fair value. Based on these computations, the grant date fair values of the performance condition-based PSU awards and the market condition-based PSU awards granted on November 20, 2024, to each nonemployee director on that date were $40.22 and $40.64 per share, respectively. The maximum grant date fair value of the PSU awards in FY 2025 (200% vesting) was $208,376 for each of the nonemployee directors. There can be no assurance that these grant date fair values will be realized by the nonemployee directors. For information regarding the number of unvested PSUs held by each nonemployee director as of September 28, 2025, see the Unvested PSUs Outstanding column in the table below. $69,098 of the amounts in the Stock Awards column represent the aggregate grant date fair values, computed in accordance with FASB ASC Topic 718, of RSU awards. The grant date fair value of these awards is calculated using the closing price of our common stock on the grant date as if these awards were vested and issued on the grant date. The grant date fair value of the RSU awards granted on November 20, 2024, to each nonemployee director was $40.22 per share. There can be no assurance that these grant date fair values will ever be realized by the nonemployee directors. For information regarding the number of unvested RSUs held by each nonemployee director as of September 28, 2025, see the Unvested RSUs Outstanding column in the Nonqualified Stock Options, Unvested PSUs, and Unvested RSUs by Director table below. Each of the nonemployee directors listed below owned the following number of nonqualified stock options, unvested PSUs, and unvested RSUs as of September 28, 2025.

  23. Nonqualified Stock Options, Unvested PSUs, and Unvested RSUs by Director

    Nonqualified Stock Options, Unvested PSUs, and Unvested RSUs by Director

  24. Nonqualified Stock Options, Unvested PSUs, and Unvested RSUs by Director

    | Name | Stock Options Outstanding (#) | Unvested PSUs Outstanding (#) | Unvested RSUs Outstanding (#) | | Mr. Birkenbeuel | 0 | 8,617 | 1,718 | | Mr. Gandhi | 0 | 8,617 | 1,718 | | Ms. Obiaya | 0 | 8,297 | 1,718 | | Dr. Ritrievi | 0 | 8,617 | 1,718 | | Ms. Volpi | 10,000 | 8,617 | 1,718 |

  25. Nonqualified Stock Options, Unvested PSUs, and Unvested RSUs by Director

    Item 2: Advisory Vote to Approve Our Named Executive Officers’ Compensation

  26. Pay Philosophy and Executive Compensation Components

    Pay Philosophy and Executive Compensation Components We believe in a pay for performance compensation program in which a majority of the compensation is tied to our success in meeting predetermined performance objectives and creating long-term stockholder value. The objective of this strategy is to motivate our executives to achieve our annual and long-term financial goals, align with stockholders, and recognize the executives’ contributions in delivering strong corporate and/or business group performance. The Compensation Committee implements this philosophy and provides incentives to our executives by following three key principles: • Positioning target total direct compensation (TDC) and each component thereof at approximately market median with additional consideration given to various factors as discussed previously. An NEO’s pay positioning is not formulaic; failure to achieve financial objectives and create stockholder value should directly impact TDC relative to market median compensation • Aligning our annual incentive awards with our AOP and key financial and strategic objectives, which are predetermined and objectively measurable • Rewarding long-term performance using metrics such as EPS growth and relative TSR, which focuses executives on consistent and sustainable stockholder value creation The Compensation Committee references 25th percentile, median and 75th percentile TDC and compensation components of companies similar in size, scope, and complexity with which we compete for executive talent, and then further considers responsibilities, individual performance, tenure, retention, company performance, succession planning, and market factors for each executive to make final pay decisions. The Committee believes this varied positioning and approach is appropriate given our business portfolio mix, the breadth of our services, and the global nature of our operations, which require our executives to have a wide range of business leadership experience and skills. Our incentive compensation for FY 2025 consisted of the AIP and LTI awards. The AIP award payouts were based on our performance against performance goals established by the Compensation Committee in November 2024 for revenue, operating income, cash flow, and backlog. The AIP rewards NEOs based on corporate and/or business group and/or division performance as well as individual contributions to motivate the NEOs and align their compensation with stockholder interests. Both our AIP and our PSU awards under our LTI program provide upside opportunity for exceeding performance targets and downside risk, including forfeiture of PSUs and no payout under our AIP for failing to achieve predetermined performance targets. Our compensation is aligned with performance, and our ability to exceed or failure to achieve our performance targets directly impacts payments to our NEOs and their compensation relative to the market median. The following graphic illustrates the components of our executive compensation program.

  27. Components of Annual and Long-Term Compensation

    Components of Annual and Long-Term Compensation In FY 2025, as shown in the following graphic, 89% of our CEO’s target TDC and an average of 74% of our other NEOs’ target TDC was at risk (all compensation components other than base salary).

  28. FY 2025 NEO TDC

    | Component | Purpose | Decisions Impacting FY 2025 Executive Compensation | | Fixed | | | | Base Salary | Provides fixed, market-competitive monthly income for performing daily responsibilities | • The Committee increased the CEO’s base salary by 2% in FY 2025 to reflect prior year performance, tenure, and overall market competitive base pay • The Committee adjusted the other NEO base salaries to reflect prior year performance or position their salaries at or around the market median, with increases ranging from 3.7% to 16.7% | | Performance-Based Cash | | | | AIP Award | Provides variable, cash-based incentive to motivate our executives annually to grow revenue, increase profitability, deliver strong cash flow, and replenish backlog consistent with our AOP financial objectives | • Target bonus opportunity, as a percentage of base salary, was 150% for the CEO, 100% for the CFO and Chief Innovation and Sustainability Officer, and 90% for the other EVPs • The corporate and business group performance factor has a range of 0 to 2.0, with a target of 1.0 based on achievement of four AOP targets (revenue, operating income, cash flow, and backlog) • The Committee may make limited adjustments to AIP payments based on individual performance and contributions • Minimum (threshold), target, and maximum performance criteria and payouts were established for each metric, with payout at 0% of target below threshold performance, 50% of target at threshold, 100% of target at target, and 200% of target at maximum. The individual performance modifier may range from +/-20% | | Long-Term Incentives | | | | PSUs and RSUs | Provide variable equity-based incentive compensation to enhance the alignment of our executives’ interests with stockholder interests and drive long-term value creation Provide LTI opportunity, including vehicle selections, performance criteria and weightings based on market data, our pay philosophy, and independent consultant recommendations | • For FY 2025, the value of the target LTI opportunities for the NEOs were adjusted to target the market median while also considering internal equity, retention, and individual performance and role, among other factors • PSUs have a three-year performance period with cliff vesting, subject to achievement of the applicable performance goals; vesting is determined 50% by EPS growth and 50% by relative TSR: ◦ EPS based vesting ranges from 0% for less than 2% average annual EPS growth to 200% for greater than or equal to 16% average annual EPS growth ◦ TSR based vesting ranges from 0% if our TSR is less than the 25th percentile of the TSR peer group to 200% if our TSR is at the 75th or higher percentile of the TSR peer group • RSUs have time-based vesting at the rate of 25% per year, subject to the holder’s continuous employment by us through the applicable vesting date |

  29. FY 2025 AIP Award Program

    FY 2025 AIP Award Program The Compensation Committee grants AIP awards under our Executive Compensation Plan approved by our stockholders in 2014. No amounts are paid under the Executive Compensation Plan unless we have positive net income (as defined under the Plan). The AIP awards are used to motivate NEOs to meet and exceed annual company objectives. These incentives are paid to reward the achievement of specified operating, financial, strategic, and individual measures and goals that are expected to contribute to stockholder value creation.

  30. AIP Performance Measures and Targets

    AIP Performance Measures and Targets The AIP uses four financial metrics when the Committee is determining payments under the Executive Compensation Plan. Each November, a target level is established for each of the four financial metrics based on the AOP for the business groups, as well as the Company as a whole. In setting the targets, the Board and Compensation Committee aim to align our long-term financial goals and the drivers of our long-term stockholder value. The four financial metrics, including rationale for their inclusion in the AIP and the results of the FY 2025 AIP, are illustrated in the table below.

  31. AIP Award Program Financial Metrics

    AIP Award Program Financial Metrics

  32. AIP Award Program Financial Metrics

    | Metric | FY 2025 Weighting | What it Measures and How It Aligns | Threshold/ Maximum as a % of Target | FY 2025 Target1 ($ in thousands) | FY 2025 Actual2 ($ in thousands) | FY 2024 Actual2 ($ in thousands) | | Revenue | 20% | Measures the growth of our business and is a leading driver of stockholder value creation. Aligns with our growth and durable competitive advantage drivers. | 85% / 115% | Corporate: $5,700,000 GSG: $2,847,000 CIG: $2,920,000 | Corporate: $5,442,590 GSG: $2,673,909 CIG: $2,822,865 | Corporate: $5,198,724 GSG: $2,483,355 CIG: $2,786,775 | | Operating Income | 40% | Primary measure used by stockholders and analysts to evaluate our profitability. Aligns with our margin, durable competitive advantage, and ERM drivers. | 75% / 125% | Corporate: $575,000 GSG: $298,000 CIG: $348,000 | Corporate: $603,607 GSG: $340,551 CIG: $355,795 | Corporate: $510,498 GSG: $281,026 CIG: $332,000 | | Cash Flow | 20% | Demonstrates our ability to collect on receivables billed to clients and allows us to invest in our business and return funds to stockholders through dividends and share repurchases. Aligns with our capital allocation driver. | 75% / 125% | Corporate: $376,000 GSG: $314,000 CIG: $381,000 | Corporate: $554,685 GSG: $361,593 CIG: $369,646 | Corporate: $358,724 GSG: $272,371 CIG: $352,875 | | Backlog | 20% | Positions us for growth going forward based upon authorized and funded projects. Aligns with our growth and durable competitive advantage drivers. | 85% / 115% | Corporate: $5,650,000 GSG: $3,290,000 CIG: $2,364,000 | Corporate: $4,139,502 GSG: $1,979,521 CIG: $2,167,244 | Corporate: $5,376,056 GSG: $3,196,066 CIG: $2,238,291 |

  33. AIP Award Program Financial Metrics

    1 Corporate AOP is based on business group AOPs, augmented by planned acquisitions, that are aligned with our business and stockholder interests. The AOPs for business groups include no acquisitions, since capital allocation strategy is implemented at Corporate. 2 With respect to Corporate, results exclude the impact of acquisition related charges, non-core disposition related charges, and one-time, non-recurring tax adjustments in FY 2025. With respect to the business groups, results include only 50% of the impact of acquisitions in FY 2025. This inclusion reflects the business group presidents’ responsibility to oversee the performance of and successfully integrate acquisitions. The AIP awards for our NEOs are based on the level of achievement of performance of the business for which they were responsible. The chart below indicates respective weightings for business performance for each NEO. Minimum (threshold), target, and maximum performance criteria and payouts were established for each metric as indicated above. Payout percentages are reflected in the table below with straight line interpolation for performance between threshold and target and between target and maximum. No bonus is earned with respect to a metric if performance is below threshold, and no additional bonus is earned for performance above maximum.

  34. Payout Percentages

    Payout Percentages

  35. Payout Percentages

    | Performance Level | Payout | | Less than Threshold | 0% | | Threshold | 50% | | Target | 100% | | Maximum | 200% |

  36. Payout Percentages

    Further, a financial modifier or “growth factor,” is applied to adjust the payout, either upward or downward, based on whether the AOP target is aggressive or conservative as compared to the prior year. This growth factor assists in validating the rigor of our AOP goals. Additional details on both the financial and individual performance elements of our AIP are provided below.

  37. AIP Award Formula

    AIP Award Formula NEO AIP awards are determined using the following formula.

  38. FY 2025 AIP Awards

    FY 2025 AIP Awards Our NEOs received the AIP awards shown in the following table for FY 2025, based on their respective base salary at fiscal year-end (FYE) 2025, AIP opportunity, financial modifier, and individual performance modifier.

  39. FY 2025 AIP Awards by NEO

    FY 2025 AIP Awards by NEO

  40. FY 2025 AIP Awards by NEO

    | Name | FY 2025 Base Salary ($) | Target Award Percentage (%) | Financial Modifier (CPF) | Individual Performance Modifier | AIP Award ($) | | Mr. Batrack | 1,250,000 | 150 | 1.114 | 1.200 | 2,506,500 | | Mr. Burdick | 700,000 | 100 | 1.114 | 1.200 | 935,760 | | Dr. Shoemaker | 700,000 | 100 | 1.114 | 1.200 | 935,760 | | Mr. Hopson | 600,000 | 90 | 1.114 | 1.200 | 721,872 | | Mr. Argus | 600,000 | 90 | 1.072 | 1.200 | 694,656 |

  41. FY 2025 LTI Award Program

    FY 2025 LTI Award Program Our LTI program provides variable incentive compensation to enhance the alignment of executive interests with stockholder interests, with an emphasis on performance-based vesting. Accordingly, the LTI awards granted in FY 2025 comprised the following.

  42. PSU and RSU Percentages of FY 2025 LTI Awards

    PSU and RSU Percentages of FY 2025 LTI Awards

  43. PSU and RSU Percentages of FY 2025 LTI Awards

    | Type of Award | % of LTI (by value) | Vesting | Rationale | | PSUs | 60% | Determined at conclusion of a three-year performance period, with vesting determined 50% by EPS growth and 50% by relative TSR and subject to the holder’s continuous employment by Tetra Tech through the applicable vesting date | Performance-based; alignment with stockholder interests | | RSUs | 40% | 25% per year, subject to the holder’s continuous employment by Tetra Tech through the applicable vesting date | Retention; facilitate stock ownership; alignment with stockholder interests |

  44. PSU and RSU Percentages of FY 2025 LTI Awards

    In FY 2025, the Compensation Committee granted the LTI awards shown in the following table. The target LTI value for each NEO was determined by the Compensation Committee and targeted within a competitive range of the market median, while internal equity, retention, and individual performance and role—among other factors—were also considered. The number of PSUs and RSUs awarded to each NEO was based on the closing price for shares of our common stock on November 16, 2024. As a result of the required use of accounting methodology for determining grant date fair value in the Summary Compensation Table on page 57 of this proxy statement for PSUs with TSR vesting, certain total LTI values exceeded the corresponding target LTI values. The amounts listed in the table include the grant date fair value of PSUs, without adjustment for forfeitures. The actual number of shares issued can range from 0% to 200% of the target shares at the time of grant. The performance condition component of the fair value of PSUs was determined based on the fair market value of our common stock on the date of grant. The market condition component of the fair value of the PSUs was determined as of the date of grant using the Monte Carlo simulation method, which uses multiple input variables to estimate the probability of meeting the performance objectives established for the award, including the volatility of our stock price and other assumptions appropriate for determining fair value. The amounts also include the grant date fair value of RSUs, without adjustment for forfeitures, using the closing price per share of our common stock on the grant date.

  45. FY 2025 NEO LTI Awards

    FY 2025 NEO LTI Awards

  46. FY 2025 NEO LTI Awards

    | Name | Target LTI Value for FY 2025 ($) | PSUs (#) | PSUs ($) | RSUs (#) | RSUs ($) | Grant Date Fair Value ($)1 | | Mr. Batrack | 7,875,000 | 115,979 | 4,689,031 | 77,320 | 3,109,810 | 7,798,841 | | Mr. Burdick | 1,500,000 | 22,091 | 893,139 | 14,728 | 592,360 | 1,485,499 | | Dr. Shoemaker | 1,500,000 | 22,091 | 893,139 | 14,728 | 592,360 | 1,485,499 | | Mr. Hopson | 1,000,000 | 14,728 | 595,453 | 9,818 | 394,879 | 990,333 | | Mr. Argus | 1,000,000 | 14,728 | 595,453 | 9,818 | 394,879 | 990,333 |

  47. FY 2025 NEO LTI Awards

    1 Accounting value as determined under Accounting Standards Codification (ASC) Topic 718. LTI awards are generally granted annually after the close of the fiscal year. The Compensation Committee’s policy is to grant these equity awards following the public release of our fourth quarter and fiscal year financial results, during an open trading window, and to establish grant dates in advance.

  48. Performance Stock Units: Three-Year Performance Period

    Performance Stock Units: Three-Year Performance Period The PSUs awarded to our NEOs cliff vest after a three-year performance period, subject to achievement of the applicable performance goals. Vesting is based 50% upon our EPS growth and 50% upon relative TSR performance. Since target LTI opportunity is set within a competitive range of the market median, TSR performance at the 50th percentile of the TSR peer group would result in payments from TSR vesting within a competitive range of the market median. If TSR performance is less than the 50th percentile, the resulting payments would be appropriately below market median. With respect to the determination of EPS growth, PSUs will vest based on adjusted EPS achieved during the performance period. EPS growth will be measured by averaging EPS change on a point-to-point basis during the three-year performance period.

  49. Performance Stock Units: Three-Year Performance Period

    | Vesting Credit % | EPS Growth | | 0% | Less than 2% year-over-year growth | | 100% | 9% year-over-year growth | | 200% | 16% year-over-year growth |

  50. Performance Stock Units: Three-Year Performance Period

    Our adjusted EPS is the fully diluted EPS from our continuing operations, which is then adjusted to reflect the impacts from the following in order to ensure consistency during the vesting period: • Goodwill impairment Accounting changes requiring current and prior period adjustments due to materiality Changes in newly issued or existing accounting principles • The settlement of tax audits for more or less than amounts previously recorded • Gains or losses from dispositions of subsidiaries and significant business lines • Impact of adjustments to earn out liabilities related to acquisitions • Costs incurred in connection with acquisitions, mergers, or debt restructurings Our relative TSR performance is measured as our percentile ranking versus the S&P 400. Beginning with the November 2024 grants, Tetra Tech moved from using an equal weight on an industry peer group and the S&P 1000 to using the S&P 400. Moving to a single comparator group aligns with market practice and simplifies the program while reflecting a broad market index with a large sample size. With respect to the determination of relative TSR performance, PSUs will vest based on relative TSR performance achieved during the performance period.

  51. Performance Stock Units: Three-Year Performance Period

    | Vesting Credit (%) | Performance (percentile) | | 0 | Less than 25 | | 25 | 31.25 | | 50 | 37.5 | | 75 | 43.75 | | 100 | 50 | | 125 | 56.25 | | 150 | 62.5 | | 175 | 68.75 | | 200 | Equal to or greater than 75 |

  52. Restricted Stock Units

    Restricted Stock Units All RSUs vest in equal annual installments over four years provided that the NEO remains employed by Tetra Tech through the applicable vesting date. These vesting provisions are designed to retain the services of the NEO for an extended duration.

  53. Nonqualified Deferred Compensation

    Nonqualified Deferred Compensation Our NEOs are eligible to participate in our nonqualified Deferred Compensation Plan (DCP), which allows eligible employees to defer up to 80% of their base salary, AIP award, and PSU/RSU awards. The plan provides NEOs, other eligible employees, and nonemployee directors with a long-term capital accumulation opportunity because savings accumulate on a pretax basis. Participants may select from a number of investment options. The plan does not offer above-market interest rates. Deferrals are 100% vested. We do not make matching or any other contributions under the plan. Refer to the Nonqualified Deferred Compensation—FY 2025 table on page 60 in this proxy statement and the details set forth following that table for additional information regarding the DCP.

  54. Termination and Change in Control

    Termination and Change in Control None of our NEOs has an employment agreement, which reflects our pay for performance philosophy. Subject to the terms of the Tetra Tech, Inc. Change of Control Severance Plan (CIC Severance Plan) described in this section, if an NEO is no longer performing at the expected level, they can be terminated immediately without receiving a contractually guaranteed payment. Our NEOs are eligible to participate in the CIC Severance Plan, which supersedes all prior change in control agreements we had with our NEOs. Our NEOs are eligible for severance payments upon termination by us “without cause” or by the executive “for good reason,” in each case, during the two-year period following (or, in the case of a termination without cause, 90-day period immediately preceding) a “change in control” of our Company (each, a “qualifying termination”), in accordance with the terms and conditions of the CIC Severance Plan. In the event of such a qualifying termination, the NEO would be eligible for (1) the following lump sum cash severance payments: (a) their current base salary plus target bonus for the fiscal year of employment termination times a multiple (the multiple is 2.0 in the case of Mr. Batrack and 1.5 in the cases of Messrs Argus, Burdick, and Hopson and Dr. Shoemaker); (b) their prorated target bonus for the fiscal year of employment termination; (c) any earned but unpaid bonus for the fiscal year immediately preceding their employment termination; and (d) an amount equal to 102% of the cost of providing medical benefits (health, dental, and vision) to the NEO and the NEO’s dependents for 24 months (in the case of Mr. Batrack), and 18 months (in the cases of Messrs. Argus, Burdick, and Hopson and Dr. Shoemaker); and (2) full vesting of outstanding unvested stock options, restricted stock, and RSUs that vest solely based on continued employment, and vesting of equity awards that vest in whole or in part on achievement of performance criteria based on the greater of target or actual performance results. No outstanding and unvested equity awards held by our NEOs would automatically vest upon a change in control. In addition, if a participant’s employment is terminated because of their death or “disability” during the two years following a change in control, the NEO would receive their prorated target bonus for the fiscal year of employment termination and any earned but unpaid bonus for the preceding fiscal year. All payments are contingent on the execution of a release and continued compliance with certain restrictive covenants set forth in the CIC Severance Plan. The payments and benefits provided for under the CIC Severance Plan would be reduced to the extent that they would trigger excise taxes under Section 4999 of the Internal Revenue Code, unless the NEO would be better off on an after-tax basis after taking into account all taxes, receiving the full amount of the payments and benefits. In this case, the payment and benefits would not be reduced. In no event is the Company obligated to provide any tax gross up or similar payment to the NEO. Refer to the Potential Payments Upon Termination or Change in Control section on page 61 in this proxy statement for additional information regarding change in control events and outstanding awards granted to the NEOs.

  55. Use of Market Survey Data and Peer Group

    Use of Market Survey Data and Peer Group The Compensation Committee began its FY 2025 process of deciding how to compensate our NEOs by considering the competitive market data provided by our independent compensation consultant, Meridian, and our human resources staff. The Compensation Committee uses the market survey data as a reference point to target TDC at or around the median, also considering factors such as tenure, individual performance, the individual’s responsibilities, market factors, and succession and retention. The Compensation Committee retains and does not delegate any of its exclusive power to determine all matters of executive compensation and benefits, although it seeks input and recommendations from the CEO and our human resources staff. Further, the Compensation Committee and the Audit Committee jointly determine the individual performance of the CFO. The Compensation Committee reports to the Board of Directors on the major items covered at each Compensation Committee meeting.

  56. Compensation Peer Group

    Compensation Peer Group The Compensation Committee worked with Meridian to develop a broad, size appropriate peer group with comparable annual revenue and market capitalization. This peer group consists of the companies listed below. No changes were made to the peer group for FY 2025.

  57. Compensation Peer Group

    | AECOM | KBR, Inc. | | Booz Allen Hamilton, Inc. | Leidos Holdings, Inc. | | CACI International Inc. | Maximus, Inc. | | Clarivate, Plc | Parsons Corporation | | Dycom Industries Inc. | Science Applications Intl. Corp | | FTI Consulting, Inc. | Verisk Analytics, Inc. | | ICF International, Inc. | |

  58. Summary Compensation Table

    Summary Compensation Table The following table shows the compensation earned by or awarded to our NEOs during FYs 2025, 2024, and 2023, in accordance with SEC regulations. Compensation as shown in the table does not necessarily reflect the compensation realized by our NEOs for those years. For example, the amounts for 2025 set forth in the Stock Awards column relating to PSUs do not represent the actual amounts realized by our NEOs; rather they represent the aggregate grant date fair value for financial reporting purposes of those PSUs, which cliff vest subject to achievement of the applicable performance goals (based on 50% by EPS growth and 50% by relative TSR) at the end of a three year performance period and ultimately may result in no such compensation being realized by the NEO.

  59. Summary of Executive Compensation by NEO

    | Name and Principal Position | Year | Salary ($)1 | Bonus2 | Stock Awards ($)3 | Non-Equity Incentive Plan Compensation ($)4 | All Other Compensation ($)5 | Total ($) | | Mr. Batrack Chairman, CEO and President | 2025 | 1,245,673 | — | 7,798,841 | 2,506,500 | 71,385 | 11,622,399 | | | 2024 | 1,220,673 | — | 7,985,017 | 3,286,112 | 68,539 | 12,560,342 | | | 2023 | 1,196,154 | — | 6,859,003 | 3,767,040 | 63,321 | 11,885,517 | | Mr. Burdick EVP, CFO | 2025 | 695,673 | 50,000 | 1,485,499 | 935,760 | 54,645 | 3,221,577 | | | 2024 | 666,346 | — | 1,368,870 | 1,207,143 | 49,737 | 3,292,095 | | | 2023 | 618,846 | 200,000 | 1,143,141 | 1,046,400 | 50,046 | 3,058,433 | | Dr. Shoemaker EVP, Chief Innovation and Sustainability Officer | 2025 | 682,692 | 50,000 | 1,485,499 | 935,760 | 46,986 | 3,200,938 | | | 2024 | 597,404 | — | 1,140,590 | 858,413 | 44,040 | 2,640,447 | | | 2023 | 585,000 | 100,000 | 1,143,141 | 897,811 | 41,788 | 2,767,740 | | Mr. Hopson EVP, Chief Legal and Human Capital Officer | 2025 | 591,346 | 50,000 | 990,333 | 721,872 | 48,927 | 2,402,478 | | | 2024 | 543,077 | — | 1,026,572 | 836,058 | 46,886 | 2,452,593 | | | 2023 | 504,615 | 100,000 | 914,466 | 800,496 | 46,371 | 2,365,948 | | Mr. Argus EVP, Corporate Development and President, CIG | 2025 | 592,308 | 50,000 | 990,333 | 694,656 | 48,976 | 2,376,272 | | | 2024 | 543,077 | — | 1,026,572 | 694,705 | 47,520 | 2,311,874 | | | 2023 | 504,615 | — | 914,466 | 717,484 | 53,976 | 2,190,541 |

  60. Grants of Plan Based Awards–FY 2025

    Grants of Plan Based Awards–FY 2025 The following table provides information regarding grants of plan-based incentive awards made to our NEOs during FY 2025.

  61. Grants of Plan Based Awards–FY 2025

    | | | Estimated Possible Payouts under Non-Equity Incentive Plan Awards | | | Estimated Possible Payouts under Equity Incentive Plan Awards | | | All Other Stock Awards: Shares of Stock or Units (#) | All Other Option Awards: Securities Underlying Options (#) | Exercise or Base Price of Option Awards ($) | Grant Date Fair Value of Stock and Option Awards ($) | | Name | Grant Date | Threshold ($) | Target ($) | Maximum ($) | Threshold (#) | Target (#) | Maximum (#) | | | | | | Mr. Batrack | 1 | 0 | 1,875,000 | 3,750,000 | | | | | | | | | | 11/20/242 | | | | 0 | 115,979 | 231,958 | | | | 4,689,031 | | | 11/20/243 | | | | | | | 77,320 | | | 3,109,810 | | Total | | | | | | | | | | | 7,798,841 | | Mr. Burdick | 1 | 0 | 700,000 | 1,400,000 | | | | | | | | | | 11/20/242 | | | | 0 | 22,091 | 44,182 | | | | 893,139 | | | 11/20/243 | | | | | | | 14,728 | | | 592,360 | | Total | | | | | | | | | | | 1,485,499 | | Dr. Shoemaker | 1 | 0 | 700,000 | 1,400,000 | | | | | | | | | | 11/20/242 | | | | 0 | 22,091 | 44,182 | | | | 893,139 | | | 11/20/243 | | | | | | | 14,728 | | | 592,360 | | Total | | | | | | | | | | | 1,485,499 | | Mr. Hopson | 1 | 0 | 540,000 | 1,080,000 | | | | | | | | | | 11/20/242 | | | | 0 | 14,728 | 29,456 | | | | 595,453 | | | 11/20/243 | | | | | | | 9,818 | | | 394,879 | | Total | | | | | | | | | | | 990,333 | | Mr. Argus | 1 | 0 | 540,000 | 1,080,000 | | | | | | | | | | 11/20/242 | | | | 0 | 14,728 | 29,456 | | | | 595,453 | | | 11/20/243 | | | | | | | 9,818 | | | 394,879 | | Total | | | | | | | | | | | 990,333 |

  62. Grants of Plan Based Awards–FY 2025

    1 This row represents the possible AIP awards for FY 2025. Additional information about these payments appears in the Compensation Discussion and Analysis section on page 36 of this proxy statement. The actual award payments, as determined by the Compensation Committee on November 9, 2025, are included in the Non-Equity Incentive Plan Compensation ($) column of the Summary Compensation Table on page 57 of this proxy statement. The target and maximum values are calculated by multiplying (a) 150% and 300%, respectively, by Mr. Batrack’s annual base salary; (b) 100% and 200%, respectively, by Mr. Burdick’s and Dr. Shoemaker’s annual base salaries; and (c) 90% and 180%, respectively, by Mr. Argus’s and Mr. Hopson’s annual base salaries, each as in effect at the end of FY 2025. 2 The amounts shown in this row reflect, in share amounts, the threshold, target, and maximum potential payouts of PSUs, as further discussed in the Compensation Discussion and Analysis section on page 36 of this proxy statement. The PSUs were granted under the 2018 Equity Incentive Program (EIP) and cliff vest in shares of our common stock after the end of a three-year performance period, subject to the achievement of the applicable performance goals. Vesting, from 0% to 200% of the award, is completely at risk and is based 50% upon our EPS growth and 50% upon our relative TSR. For additional details on the grant date fair value of these PSUs, see footnote (3) of the Summary Compensation Table on page 57 of this proxy statement. Dividend equivalents are payable on the underlying PSU shares, but only to the extent that the applicable performance goals are subsequently satisfied and the PSUs vest. 3 The amounts shown in this row reflect the awards of RSUs, as further discussed in the Compensation Discussion and Analysis section on page 36 of this proxy statement. The RSUs were granted under the 2018 EIP and vest as to 25% of the award on November 30, 2025, and on each anniversary of that date until fully vested, subject to the holder’s continuous employment by us through the applicable vesting date. For additional details on the grant date fair value of these RSUs, see footnote (3) of the Summary Compensation Table on page 57 of this proxy statement.

  63. Outstanding Equity Awards at Fiscal Year End (FYE) 2025

    Outstanding Equity Awards at Fiscal Year End (FYE) 2025 The following table provides information regarding NEO equity awards outstanding as of September 28, 2025, the FYE 2025.

  64. Outstanding Equity Awards at Fiscal Year End (FYE) 2025

    | | Option Awards | | | | Stock Awards | | | | | Name | Number of Securities underlying Unexercised Options Exercisable (#) | Securities underlying Unexercised Options Unexercisable (#) | Option Exercise Price ($) | Option Expiration Date | Shares or Units of Stock Not Vested (#) | Market Value of Shares or Units of Stock Not Vested ($)1 | Unearned Shares, Units, or Other Rights Not Vested (#) | Market or Payout Value of Unearned Shares, Units, or Other Rights Not Vested ($)1 | | Mr. Batrack | — | — | | | 14,0302 | 467,620 | | | | | | | | | 38,0253 | 1,267,373 | | | | | | | | | 63,7604 | 2,125,121 | | | | | | | | | 77,3205 | 2,577,076 | | | | | | | | | | | 114,0856 | 3,802,453 | | | | | | | | | 127,5207 | 4,250,242 | | | | | | | | | 115,9798 | 3,865,580 | | Total | — | — | | | 193,135 | 6,437,190 | 357,854 | 11,918,275 | | Mr. Burdick | — | — | | | 2,5202 | 83,992 | | | | | | | | | 6,3353 | 211,146 | | | | | | | | | 10,9304 | 364,297 | | | | | | | | | 14,7285 | 490,884 | | | | | | | | | | | 19,0156 | 633,770 | | | | | | | | | 21,8607 | 728,594 | | | | | | | | | 22,0918 | 736,293 | | Total | — | — | | | 34,513 | 1,150,318 | 62,966 | 2,098,657 | | Dr. Shoemaker | — | — | | | 2,5202 | 83,992 | | | | | | | | | 6,3353 | 211,146 | | | | | | | | | 9,1054 | 303,470 | | | | | | | | | 14,7285 | 490,884 | | | | | | | | | | | 19,0156 | 633,770 | | | | | | | | | 18,2157 | 607,106 | | | | | | | | | 22,0918 | 736,293 | | Total | — | — | | | 32,688 | 1,089,491 | 59,321 | 1,977,169 | | Mr. Hopson | — | — | | | 2,0552 | 68,493 | | | | | | | | | 5,0703 | 168,983 | | | | | | | | | 8,1954 | 273,139 | | | | | | | | | 9,8185 | 327,234 | | | | | | | | | | | 15,2106 | 506,949 | | | | | | | | | 16,3957 | 546,445 | | | | | | | | | 14,7288 | 490,884 | | Total | — | — | | | 25,138 | 837,850 | 46,333 | 1,544,279 |

  65. Outstanding Equity Awards at Fiscal Year End (FYE) 2025

    | | Option Awards | | | | Stock Awards | | | | | Name | Number of Securities underlying Unexercised Options Exercisable (#) | Securities underlying Unexercised Options Unexercisable (#) | Option Exercise Price ($) | Option Expiration Date | Shares or Units of Stock Not Vested (#) | Market Value of Shares or Units of Stock Not Vested ($)1 | Unearned Shares, Units, or Other Rights Not Vested (#) | Market or Payout Value of Unearned Shares, Units, or Other Rights Not Vested ($)1 | | Mr. Argus | — | — | | | 2,0552 | 68,493 | | | | | | | | | 5,0703 | 168,983 | | | | | | | | | 8,1954 | 273,139 | | | | | | | | | 9,8185 | 327,234 | | | | | | | | | | | 15,2106 | 506,949 | | | | | | | | | 16,3957 | 546,445 | | | | | | | | | 14,7288 | 490,884 | | Total | — | — | | | 25,138 | 837,850 | 46,33 | 1,544,279 |

  66. Outstanding Equity Awards at Fiscal Year End (FYE) 2025

    1 Market value calculated based on a stock price of $33.33, the closing price of our common stock on September 26, 2025, the last trading day of our 2025 fiscal year. 2 Granted on 11/23/21; vests 25% on 11/18/22 and 25% annually for next three years. 3 Granted on 11/16/22; vests 25% on 11/18/23 and 25% annually for next three years. 4 Granted on 11/21/23; vests 25% on 11/30/24 and 25% annually for next three years. 5 Granted on 11/20/24; vests 25% on 11/30/25 and 25% annually for next three years. 6 Granted on 11/16/22; cliff vesting following three-year performance period based on EPS growth and relative TSR.

  67. Options Exercised and Stock Vested–FY 2025

    Options Exercised and Stock Vested–FY 2025 The following table shows the number of shares acquired by each of the NEOs during FY 2025 through exercising stock options and the vesting of PSUs and RSUs. The table also presents the value realized upon options being exercised and PSUs and RSUs being vested, as calculated, in the case of stock options, based on the difference between the market price of our common stock at exercise and the option exercise price and, as calculated, in the case of PSUs and RSUs, based on the closing price per share of our common stock on the Nasdaq Global Select Market on the vesting date.

  68. Options Exercised and Stock Vested–FY 2025

    | | Option Awards | | Stock Awards | | | Name | Shares Acquired on Exercise (#) | Value Realized on Exercise ($) | Shares Vested (#)1 | Value Realized on Vesting ($) | | Mr. Batrack | — | — | 225,591 | 9,145,180 | | Mr. Burdick | — | — | 40,850 | 1,656,127 | | Dr. Shoemaker | — | — | 26,335 | 1,071,553 | | Mr. Hopson | — | — | 33,100 | 1,341,704 | | Mr. Argus | — | — | 32,895 | 1,333,275 |

  69. Nonqualified Deferred Compensation–FY 2025

    Nonqualified Deferred Compensation–FY 2025 The following table shows each NEO’s contributions and earnings during FY 2025 and account balance as of September 28, 2025, under our DCP.

  70. Nonqualified Deferred Compensation–FY 2025

    | Name1 | Executive Contributions in Last Fiscal Year ($)2 | Tetra Tech Contributions in Last Fiscal Year ($) | Aggregate Earnings in Last Fiscal Year ($)3 | Aggregate Withdrawals or Distributions ($)4 | Aggregate Balance at Last Fiscal Year End ($)5 | | Mr. Batrack | 146,660 | — | (7,778,717) | — | 24,543,358 | | Mr. Burdick | — | — | 661,446 | — | 7,518,193 | | Dr. Shoemaker | 605,328 | — | (87,536) | — | 4,145,271 |

  71. Nonqualified Deferred Compensation–FY 2025

    1 Mr. Hopson and Mr. Argus are not included in this table because they do not participate in the DCP. 2 These amounts were included in the Salary ($) and/or Non-Equity Incentive Plan Compensation ($) columns, as applicable, of the Summary Compensation Table on page 57 of this proxy statement. 3 None of the amounts are included in the Summary Compensation Table on page 57 of this proxy statement because plan earnings were not preferential or above market. The amount for Mr. Batrack includes $8,020,275, representing the stock price appreciation of Tetra Tech stock units deferred into the DCP. There is no guarantee that the earnings associated with the deferred Tetra Tech stock units will be realized by Mr. Batrack. 4 These amounts were included in the Salary ($) and/or Non-Equity Incentive Plan Compensation ($) columns, as applicable, of the Summary Compensation Table on page 57 of this proxy statement at the time such compensation was earned. 5 As of September 26, 2025, which was the last business day of FY 2025. The amount for Mr. Batrack includes $20,452,621, representing the value of Tetra Tech stock units deferred into the DCP. The DCP is an unfunded and unsecured deferred compensation arrangement designed to allow the participants to defer a percentage of their base salary, bonuses, director’s fees, and equity awards other than options and invest the deferrals in a manner similar to the way in which our 401(k) plan operates, but without regard to the maximum deferral limitations imposed on 401(k) plans by the Internal Revenue Code. The DCP is designed to comply with Section 409A of the Internal Revenue Code. As required by applicable law, participation in the DCP is limited to our directors and a group of our management employees, which includes our NEOs. Since the adoption of the DCP by the Board of Directors in 2006, we have not made any contribution on behalf of any director or executive officer. Amounts deferred by each participant pursuant to the DCP are credited to a bookkeeping account maintained on behalf of that participant. Amounts credited to each participant under the DCP are periodically adjusted for earnings and/or losses at rates equal to one or more of the measurement funds selected by the Compensation Committee and elected by participants. Stock unit deferrals represent shares of Tetra Tech common stock and may not be diversified into other investment options.

  72. Potential Payments upon Termination or Change in Control

    Potential Payments upon Termination or Change in Control We do not enter into employment agreements with our NEOs (or any executive officers). The CEO’s employment may be terminated at any time at the discretion of the Board of Directors. The employment of the other NEOs may be terminated at any time by the CEO with the Board’s concurrence. Our NEOs are eligible to participate in the CIC Severance Plan. Under the CIC Severance Plan, if an NEO’s employment is terminated by us “without cause” or by the NEO “with good reason,” in each case, within two years following (or, in the case of a termination without cause, a 90-day period immediately preceding) a change in control (each, a “qualifying termination”), we will pay or provide the following lump sum cash severance payments: • Severance pay equal to their current base salary plus a target bonus for the fiscal year employment terminates times a multiple (2.0 in the case of Mr. Batrack, and 1.5 in the cases of Messrs. Argus, Burdick, and Hopson and Dr. Shoemaker) • A pro rata target bonus for the year of termination, based on the number of days the NEO worked during the year • The bonus the NEO earned for the year preceding the year of termination if such bonus has not yet been paid • A payment equal to 102% of the cost of providing medical benefits (health, dental, and vision) to the NEO and their dependents substantially similar to those provided immediately prior to such termination date for 24 months (in the case of Mr. Batrack), 18 months (in the cases of Messrs. Argus, Burdick, and Hopson and Dr. Shoemaker) In addition, pursuant to the terms of the CIC Severance Plan, in connection with a qualifying termination, all outstanding and unvested stock options, restricted stock, and RSUs that vest solely based on continued employment will fully vest, and equity awards that vest in whole or in part on achievement of performance criteria will vest based on actual performance results. No outstanding or unvested equity awards held by our NEOs will automatically vest upon a change in control. Under the terms of the CIC Severance Plan, if an NEO’s employment is terminated because of their death or disability, in each case, within two years following a change in control, we will pay a pro rata target bonus for the year of termination, based on the number of days the NEO worked during the year, together with the bonus the NEO earned for the year preceding the year of termination if such bonus has not yet been paid. All severance payments described above are contingent on the execution of a release and continued compliance with the restrictive covenants set forth in the CIC Severance Plan (i.e., confidentiality and non-solicitation of employees, clients, suppliers, licensees, or business relations for a post termination period of 24 months for Mr. Batrack and 18 months for Mesrrs. Argus, Burdick and Hopson, and Dr. Shoemaker). Each NEO will also be paid or provided with any unpaid base salary, accrued vacation, and unreimbursed expenses through the date of their employment termination, together with any benefits to which the NEO is entitled under our benefits programs. The payments and benefits provided for under the CIC Severance Plan will be reduced to the extent that they would trigger excise taxes under Section 4999 of the Internal Revenue Code, unless an NEO would be better off on an after-tax basis, after taking into account all taxes, receiving the full amount of the payments and benefits. In that case, the payments and benefits will not be reduced. In no event is the Company obligated to provide any tax gross up or similar payment to the NEOs. A “change in control” for purposes of the CIC Severance Plan generally consists of one or more of the following events: • An acquisition by any person of beneficial ownership of securities representing 50% or more of the combined voting power of Tetra Tech’s voting securities (on one date or during any 12-month period) • The consummation of a merger, reorganization, or consolidation if Tetra Tech’s stockholders (together with any trustee or fiduciary acquiring securities under any benefit plan) do not own more than 50% of the combined voting power of the merged, reorganized, or consolidated Company’s then outstanding securities (other than a recapitalization in which no person acquires more than 50% of the combined voting power of our outstanding securities) • The consummation of a sale of all or substantially all Tetra Tech’s assets (other than a sale to an entity in which our stockholders own 50% or more of the voting securities of such entity) “Good reason” for purposes of the CIC Severance Plan generally includes any of the following actions by Tetra Tech: • A material diminution of the NEO’s base salary, annual bonus opportunity, or both • A material diminution in the NEO’s authority, duties, or responsibilities • A material diminution in the budget over which the NEO retains authority • A material change in the geographic location at which the NEO must perform their services An NEO will be entitled to terminate their employment for good reason only if they have provided Tetra Tech with notice of the occurrence of a condition described above within 60 days of its initial existence and we have failed to remedy such condition within 30 days after receipt of the notice. An NEO’s employment will be deemed to have been terminated following a change in control by the NEO for good reason if the NEO terminates their employment prior to a change in control for good reason if a good reason condition occurs at the direction of a person or entity who has entered into an agreement with Tetra Tech, the consummation of which will constitute a change in control. “Cause” means one of the following: • The willful and continued failure of the NEO to perform substantially their duties (other than a failure resulting from incapacity due to physical or mental illness) after a written demand for substantial performance is delivered to the NEO by the Board of Directors or CEO that specifically identifies the manner in which the Board of Directors or CEO believes that the NEO has not substantially performed their duties • The willful engaging by the NEO in illegal conduct or gross misconduct that is materially and demonstrably injurious to the Company For purposes of this definition of “cause,” no act or failure to act on the part of an NEO will be considered “willful” unless it is done, or is not done, by the NEO in bad faith or without reasonable belief that the NEO’s action or omission was in Tetra Tech’s best interests. Any act, or failure to act, based upon authority given pursuant to a resolution duly adopted by the Board of Directors or upon the instructions of our CEO, one of our executive officers or upon the advice of our legal counsel will be conclusively presumed to be done, or not done, by the NEO in good faith and in our best interests.

  73. Pay Ratio Disclosure

    Pay Ratio Disclosure As required by Section 953(b) of the Dodd Frank Wall Street Reform and Consumer Protection Act (Dodd-Frank Act) and Item 402(u) of Regulation S-K under the Securities Act, Tetra Tech is providing the following information about the relationship of the annual total compensation of our employees (excluding our CEO) and the annual total compensation of Mr. Batrack, our Chairman of the Board and CEO. The pay ratio was calculated in a manner consistent with Item 402(u) of Regulation S-K and based upon our reasonable judgment and assumptions. For FY 2025, CEO compensation, which was earned but not realized, was $13,901,508; the median employee compensation (excluding our CEO) was $104,777; and our estimate of the CEO pay ratio was 133. To determine the median employee compensation, we reviewed compensation data from Tetra Tech’s global employee population as of July 1, 2025 As of July 1, 2025, the global population was 21,433. The U.S. portion of this population was 9,739. To identify the median employee compensation, earnings figures for the 39-week period of October 1, 2024, through July 1, 2025, were collected. Non-U.S. dollar earnings were converted to U.S. dollars based on the exchange rate on July 1, 2025. For employees who worked a partial year due to a hire date that fell after the start of the fiscal year, their earnings were annualized. Earnings were not annualized for casual employees. This information is being provided for compliance purposes. Neither the Compensation Committee nor our management used the pay ratio measure in making compensation decisions. Given the different methodologies that companies use to determine an estimate of their pay ratio, the estimated ratio reported above should not be used as a basis for comparison between companies. As required by Section 953(a) of the Dodd-Frank Wall Street Reform and Consumer Protection Act, and Item 402(v) of Regulation S-K, we are providing the following information about the relationship between “compensation actually paid” to our CEO and to our other Named Executive Officers (NEOs) and certain financial performance of the Company. Compensation actually paid, as determined under SEC requirements, does not reflect the actual amount of compensation earned by or paid to our executive officers during a covered fiscal year. For further information concerning the Company’s pay-for-performance philosophy and how the Company aligns executive compensation with the Company’s performance, please refer to the Compensation Discussion and Analysis.

  74. Pay versus Performance Table

    Pay versus Performance Table

  75. Pay versus Performance Table

    | | | | | | Value of Initial Fixed $100 Invested Based On: | | | | | Year1 | SCT Total Compensation for CEO | Compensation Actually Paid to CEO2 | Average SCT Total Compensation for Other NEOs | Average Compensation Actually Paid to Other NEOs3 | Company TSR | Peer Group4 | Net Income ($M) | Revenue5 ($M) | | 2025 | $11,622,399 | $5,688,846 | $2,800,316 | $1,921,443 | $188.30 | $195.71 | $247.9 | $5,442.6 | | 2024 | $12,560,342 | $24,898,843 | $2,674,252 | $4,579,192 | $263.94 | $199.05 | $333.4 | $5,198.7 | | 2023 | $11,885,517 | $16,020,470 | $2,595,666 | $3,337,863 | $169.64 | $144.97 | $273.4 | $4,522.6 | | 2022 | $10,331,897 | $9,306,681 | $2,318,379 | $2,065,988 | $142.49 | $110.07 | $263.1 | $3,504.0 | | 2021 | $7,908,335 | $18,481,077 | $2,109,249 | $3,740,891 | $167.37 | $116.88 | $232.8 | $3,212.5 |

  76. Pay versus Performance Table

    Notes: 1 The CEO and other NEOs for the indicated years were as follows: (i) for 2025, our CEO was Batrack and our other NEOs were Burdick, Shoemaker, Hopson, and Argus (ii) for 2024, our CEO was Batrack and our other NEOs were Burdick, Shoemaker, Hopson, and Argus (iii) for 2023, our CEO was Batrack and our other NEOs were Burdick, Shoemaker, Hopson, and Argus, (iv) for 2022, our CEO was Batrack and our other NEOs were Burdick, Shoemaker, Amidon, and Hopson, (v) and for 2021, our CEO was Batrack and our other NEOs were Burdick, Shoemaker, Argus, and Hopson. 2 Amounts reported in this column are based on total compensation reported for our CEO in the Summary Compensation Table for the indicated fiscal years and adjusted as shown in the tables below. Fair value of equity awards was computed in accordance with the Company’s methodology used for financial reporting purposes.

  77. Pay versus Performance Table

    | Fiscal Year | Summary Compensation Table Total | Adjustment to Summary Compensation Table Total1 | Compensation Actually Paid | | 2025 | $11,622,399 | $(5,933,553) | $5,688,846 | | 2024 | $12,560,342 | $12,338,501 | $24,898,843 | | 2023 | $11,885,517 | $4,134,953 | $16,020,470 | | 2022 | $10,331,897 | $(1,025,216) | $9,306,681 | | 2021 | $7,908,335 | $10,572,742 | $18,481,077 |

  78. Pay versus Performance Table

    1 See table below for calculation of Adjustment to Summary Compensation Table Total

  79. Pay versus Performance Table

    | Fiscal Year | Deduction of Grant Date Fair Value of Current Year Equity Awards | Addition of Fair Value of Current Year Equity Awards at FYE | Deduction for Awards Granted in Prior Years that Fail to Meet Vesting Criteria | Additions (Deductions) for Change in Value of Prior Years’ Awards Unvested at FYE | Additions (Deductions) for Change in Value of Prior Years’ Awards That Vested in Fiscal Year | Dollar Value of Dividends not Otherwise Reflected in the Fair Value for Covered Fiscal Year | Adjustment to Summary Compensation Table Total | | 2025 | $(7,798,841) | $7,921,988 | $0 | $(4,777,041) | $(1,327,210) | $47,552 | $(5,933,553) | | 2024 | $(7,985,017) | $11,903,114 | $0 | $7,892,963 | $479,919 | $47,522 | $12,338,501 | | 2023 | $(6,859,003) | $6,239,770 | $0 | $2,833,515 | $1,853,143 | $67,527 | $4,134,953 | | 2022 | $(6,281,608) | $3,979,305 | $0 | $(1,831,074) | $3,024,666 | $83,495 | $(1,025,216) | | 2021 | $(4,601,813) | $5,668,783 | $0 | $6,914,928 | $2,516,496 | $74,348 | $10,572,742 |

  80. Pay versus Performance Table

    3 Amounts reported in this column are based on the average of the total compensation reported for our other NEOs in the Summary Compensation Table for the indicated fiscal years and adjusted as shown in the tables below. Fair value of equity awards was computed in accordance with the Company’s methodology used for financial reporting purposes.

  81. Pay versus Performance Table

    | Fiscal Year | Average Summary Compensation Table Total | Adjustment to Average Summary Compensation Table Total1 | Average Compensation Actually Paid | | 2025 | $2,800,316 | $(878,874) | $1,921,443 | | 2024 | $2,674,252 | $1,904,939 | $4,579,192 | | 2023 | $2,595,666 | $742,198 | $3,337,863 | | 2022 | $2,318,379 | $(252,392) | $2,065,988 | | 2021 | $2,109,249 | $1,631,643 | $3,740,891 |

  82. Pay versus Performance Table

    1 See table below for calculation of Adjustment to Average Summary Compensation Table Total

  83. Pay versus Performance Table

    | Fiscal Year | Deduction of Grant Date Fair Value of Current Year Equity Awards | Addition of Fair Value of Current Year Equity Awards at FYE | Additions (Deductions) for Change in Value of Prior Years’ Awards Unvested at FYE | Additions (Deductions) for Change in Value of Prior Years’ Awards That Vested in Fiscal Year | Dollar Value of Dividends not Otherwise Reflected in the Fair Value for Covered FY | Adjustment to Average Summary Compensation Table Total | | 2025 | $(1,237,916) | $1,257,471 | $(693,872) | $(212,105) | $7,548 | $(878,874) | | 2024 | $(1,140,651) | $1,700,334 | $1,247,331 | $91,137 | $6,789 | $1,904,939 | | 2023 | $(1,028,804) | $935,927 | $520,160 | $303,504 | $11,411 | $742,198 | | 2022 | $(1,024,644) | $649,101 | $(335,039) | $441,571 | $16,620 | $(252,392) | | 2021 | $(934,781) | $1,151,515 | $1,068,729 | $333,464 | $12,715 | $1,631,643 |

  84. Pay versus Performance Table

    4 For all covered years, the peer group consisted of the following companies: AECOM, Booz Allen Hamilton Holding Co., CACI International, Clarivate Plc, Dycom Industries, FTI Consulting, Jacobs Solutions Inc., KBR Inc., Leidos Holdings, Maximus Inc., Parsons Corp., Science Applications International, and Verisk Analytics For 2025, Jacobs Solutions was added to the group. ICF International was removed from the group. Using the group from the prior disclosure, the peer group TSR would be as follows: (i) 2025: $193.83; 2024: $203.12; 2023: $144.72; 2022: $109.24; 2021: $113.29 5 In accordance with SEC rules, the Company is required to include in the Pay versus Performance table the “most important” financial performance measure (as determined by the Company) used to link compensation actually paid to our named executive officers to Company performance for the most recently completed fiscal year. The Company determined revenue, which is a metric included in our incentive program, meets this requirement and therefore, we have included this performance measure in the Pay versus Performance table.

  85. Description of the Relationship Between Compensation Actually Paid to our Named Executive Officers and Company Performance

    Description of the Relationship Between Compensation Actually Paid to our Named Executive Officers and Company Performance The charts below describe the relationship between compensation actually paid (CAP) to our chief executive officer and the average of the compensation actually paid to our other named executive officers (as calculated above) and our financial and stock performance for the indicated years. In addition, the first chart below compares our cumulative total shareholder return (TSR) and peer group cumulative TSR for the indicated years.