ICF International, Inc.

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. )

Filed by the Registrant ☒

Filed by a Party other than the Registrant ☐

Check the appropriate box:

ICF INTERNATIONAL, INC.

(Name of Registrant as Specified In Its Charter)

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

Payment of Filing Fee (Check all boxes that apply):

NOTICE OF ANNUAL MEETING OF STOCKHOLDERS TO BE

HELD ON JUNE 2, 2026

John Wasson

Chair & Chief

Executive Officer

AGENDA:

Pursuant to the Delaware General Corporation Law and ICF International’s Amended and Restated Bylaws, stockholders of record at the close of business on April 8, 2026, are entitled to notice of, and to vote at, the 2026 annual meeting of stockholders (the “Annual Meeting”). This Notice of Annual Meeting, the Proxy Statement, and a form of proxy or voting instruction form are being distributed and made available to stockholders on or about April 22, 2026.

To help manage costs and to reduce the environmental impact of the annual meeting process, the Annual Meeting will be a virtual meeting. You will not be able to attend the Annual Meeting physically. Instead, you will be able to attend the Annual Meeting, as well as vote and submit your questions, during a live webcast by visiting www.virtualshareholdermeeting.com/ICFI2026 and entering the 16-digit control number included on your notice, proxy card or voting instruction form. Further details regarding the virtual meeting format can be found in the “Voting and Meeting” section of the Proxy Statement.

We are pleased to utilize the U.S. Securities and Exchange Commission (the “SEC”) rule that allows companies to furnish their proxy materials to stockholders over the Internet. We believe that this allows us to provide you with all the information you need while lowering the costs of delivery for, as well as reducing the environmental impact of, our Annual Meeting. As a result, many of our stockholders will receive a notice of the Internet availability of our Proxy Statement and our Annual Report for the fiscal year ended December 31, 2025 (“2025 Form 10-K”). This notice contains instructions on how to access those documents over the Internet. We direct your attention to the attached Proxy Statement for more information, including instructions on how stockholders can receive a paper copy of our proxy materials, including our Proxy Statement, our 2025 Form 10-K and a form of proxy or voting instruction form. All stockholders who have previously requested to receive paper copies of proxy materials will receive a paper copy of the proxy materials by mail. Employing this electronic distribution process will conserve natural resources and reduce the costs of printing and distributing our proxy materials.

It is important that your shares of ICF International common stock be represented at the Annual Meeting in order to ensure the presence of a quorum. Even if you plan to attend the Annual Meeting via live webcast, please vote your shares of ICF International common stock in advance by mailing your completed proxy or voting instruction form, or voting electronically or telephonically, to ensure your representation at the Annual Meeting. Thank you for your cooperation and continued support of ICF International.

CAST YOUR VOTE RIGHT AWAY

We hope you will exercise your rights as a stockholder and fully participate in our virtual Annual Meeting. It is very important that you vote in order to play a part in the future of our Company. You do not need to attend the virtual Annual Meeting to vote your shares.

If you hold your shares through a broker, bank or nominee, they are not permitted to vote on your behalf for the election of directors and other matters to be considered at the Annual Meeting (except for ratification of the selection of Grant Thornton LLP as the independent registered public accounting firm for fiscal year 2026), unless you provide specific instructions by completing and returning the voting instruction form or following the instructions provided to you to vote your shares via telephone or the Internet, all as provided to you or as instructed by your broker, bank or other nominee. For your vote to be counted, you will need to communicate your voting decisions to your broker, bank or other nominee before the date of the Annual Meeting.

Even if you plan to attend our Annual Meeting via live webcast, please read the Proxy Statement with care and vote right away using any of the following methods. In all cases, have your notice, proxy card or voting instruction form in hand and follow the instructions.

PARTICIPATING IN THE ANNUAL MEETING

A summary of the information you need to participate in the Annual Meeting online is provided below:

PROXY SUMMARY

To assist you in reviewing the proposals to be acted upon at the 2026 annual meeting of stockholders (the “Annual Meeting”), we call your attention to the following information about ICF International, Inc.’s (“ICF International,” “ICF,” the “Company,” “we,” “our” or “us”) 2025 financial performance, key executive compensation actions and decisions and corporate governance highlights. The following description is only a summary. For more complete information about these topics, please review the Company’s Annual Report on Form 10-K for the year ended December 31, 2025, filed with the U.S. Securities and Exchange Commission (the “SEC”) on February 27, 2026, (the “2025 Form 10-K”), and the complete Proxy Statement that follows.

PROPOSALS WHICH REQUIRE YOUR VOTE

ABOUT ICF INTERNATIONAL

ICF provides professional services and technology-based solutions to government and commercial clients, including management, technology and policy consulting and implementation services. We help our clients conceive, develop, implement and improve solutions that address complex business, natural resources, social, technological and public safety issues. Our approximately eighty-four hundred (8,400) employees serve clients from our headquarters in the Washington D.C. metropolitan area, our approximately forty-nine (49) regional offices throughout the U.S. and the approximately fourteen (14) offices outside the U.S., including offices in the United Kingdom, Belgium, India and Canada. ICF’s website is www.icf.com.

As of December 31, 2025, ICF had total annual consolidated revenue of $1.9 billion, total consolidated assets of $2.1 billion and total consolidated stockholders’ equity of $1.0 billion.

ICF International is a Delaware corporation, and our principal executive offices are located at 1902 Reston Metro Plaza, Reston, Virginia 20190.

2025 Business Highlights

Financial Performance. All financial numbers referenced below were previously reported in the 2025 Form 10-K. Additional discussion of each of the metrics listed below can also be found in the 2025 Form 10-K.

Beginning in 2025, the professional services market in which the Company serves the federal government underwent dramatic change resulting from the implementation of numerous executive orders and significant and fundamental changes to federal procurement policies and practices. More significantly, across the federal government contracting environment, there was a major reduction in the federal government workforce of approximately 20%, accordingly to some publications. There were widespread contract and grant terminations reported to range from $1-2 trillion, further procurement consolidation advanced by the General Services Administration, and a major overhaul to the Federal Acquisition Regulations was initiated. The U.S. Congress was unable to agree on appropriations for Government Fiscal Year 2026 and a federal government shutdown began on October 1, 2025, which lasted until November 12, 2025, and resulted in the longest shutdown of the federal government in U.S. history.

The impacts of these unprecedented changes were widespread and substantially affected many federal government contractors. The Company itself saw a reduction of $279.5 million in revenue in 2025 from its U.S. federal government clients, primarily as a result of terminated contracts due to the Administration’s changing priorities and substantial disruption in the typical U.S. federal government procurement cycle.

Notwithstanding the dramatic change in its federal government business, the Company sharpened its focus in its federal government market and emphasized other growing and diversified portions of its client portfolio, which include commercial, international government and U.S. state and local government clients. The Company was therefore able to offset the impacts to its federal business with increases of $117.2 million, $8.5 million, and $6.9 million from its commercial, international government, and U.S. state and local government clients, respectively. Despite the major challenges presented at the outset of the year, the Company and its management exceeded its initial guidance framework and it did so despite a six-week U.S. government shutdown that occurred late in fiscal year 2025. The Company also maintained margins that were similar to 2024, despite the revenue decline. Furthermore, the Company ended 2025 with a firm backlog, a healthy book-to-bill ratio of 1.19 and a business development pipeline of $8.6 billion, reflecting effective execution on existing contracts and agility in capturing new business opportunities with capabilities that support laying the foundation for a return to growth in 2026.

Despite the challenges faced in 2025, this performance underscores the Company’s competitive strengths, namely its diversified business model, deep domain expertise, and cross-cutting technology offerings, most of which are provided under outcome-based or fixed price contracts.

COMPENSATION HIGHLIGHTS

The Human Capital Committee of the Board (the “Human Capital Committee”) approved the following actions during fiscal year 2025 to maintain governance best practices and the pay-for-performance nature of our executive compensation program:

For additional information on compensation-related matters, see the Compensation Discussion & Analysis (the “CD&A”) section of this Proxy Statement, beginning on Page 47.

2025 EXECUTIVE TOTAL COMPENSATION MIX

Under our executive compensation program, a significant portion of the 2025 Chair, President and Chief Executive Officer’s (“CEO’s”) and other NEOs’ annual total compensation opportunity is variable (85.3% and 72.9% respectively), based on our operating performance and/or our stock price.

CORPORATE GOVERNANCE HIGHLIGHTS

✔ The Board reflects a range of talents, ages, skills, perspectives, and expertise. ✔ Each director attended over 75% of applicable Board/committee meetings in 2025. ✔ The Board has three (3) independent standing committees, each operating under a written charter, chaired by an independent director and composed entirely of independent directors: Audit, Human Capital, and Governance and Nominating. ✔ The Board has adopted comprehensive Corporate Governance Guidelines to guide its oversight and leadership. ✔ The Governance and Nominating Committee regularly reviews director education opportunities available to the Board and has identified a series of courses and programs suited to the Directors’ service on the Board and Board committees. ✔ While management is responsible for the day-to-day management of risk, the Board has responsibility for the oversight of enterprise risk management and the annual enterprise risk management plan. ✔ The Board conducts an annual evaluation of the Chair and CEO. ✔ ICF has stock ownership guidelines for directors and executive officers. ✔ Pursuant to our Hedging and Pledging Policy, short sales and other hedging transactions, pledging and establishment of margin accounts are fully restricted from use by directors and executive officers. ✔ The Board reviews management talent and succession planning annually. ✔ No stockholder rights plan or “poison pill” has been adopted. ✔ The Human Capital Committee, in conjunction with an independent compensation consultant, routinely reviews our pay-for-performance executive compensation program. ✔ Neither the Board nor management has engaged in related party transactions. ✔ The severance agreements with the NEOs have a “double trigger” in connection with any severance benefits payable following a change of control. ✔ The Company maintains compensation recovery policies and practices, including a Nasdaq-compliant Compensation Recovery Policy, as well as compensation recovery provisions (including upon events of fraud or detrimental conduct that causes reputational harm to the Company) in its equity compensation plan and related award agreements and severance arrangements. ✔ The Human Capital Committee annually reviews an assessment of compensation-related risks, as more fully described in the CD&A. ✔ The Board has a strong Lead Independent Director with clearly articulated responsibilities. ✔ All current directors are independent, except Mr. Wasson, the Chair and CEO. ✔ The Company has a majority voting standard in uncontested director elections. ✔ The Board holds regular executive sessions of non-management directors. ✔ The Board and its committees conduct an annual evaluation process, in the form of either a self-evaluation or an external evaluation.

STOCKHOLDER ACTIONS

ELECT THREE DIRECTORS TO SERVE FOR A TERM EXPIRING AT OUR ANNUAL MEETING IN 2029 (PROPOSAL 1)

Stockholders are being asked to elect three (3) director nominees to our Board of Directors. You will find important information in this Proxy Statement about the qualifications and experience of each of the director nominees you are being asked to elect. The Governance and Nominating Committee performs an annual assessment to evaluate whether ICF’s directors have the skills and experience to effectively oversee the Company. Each of our director nominees is a current director of the Company and has demonstrated leadership ability, sound judgment, integrity and a commitment to the success of our Company.

Director Nominees

PROVIDE AN ADVISORY VOTE REGARDING ICF INTERNATIONAL’S OVERALL

PAY-FOR-PERFORMANCE NAMED EXECUTIVE OFFICER COMPENSATION PROGRAM (PROPOSAL 2)

Stockholders are being asked to cast a non-binding, advisory vote on our overall pay-for-performance NEO compensation program. Last year, approximately ninety-eight percent (98%) of the votes cast by our stockholders supported ICF’s overall pay-for-performance executive compensation program. In evaluating this year’s Say on Pay proposal, we recommend that you carefully review the CD&A section of this Proxy Statement which explains how and why the Human Capital Committee arrived at its executive compensation actions and decisions for 2025.

APPROVE THE ICF INTERNATIONAL, INC. 2026 OMNIBUS INCENTIVE PLAN (PROPOSAL 3)

Stockholders are being asked to vote in favor of the Company’s adoption of the ICF International, Inc. 2026 Omnibus Incentive Plan (the “2026 Incentive Plan”). If approved, the 2026 Incentive Plan will replace the ICF International, Inc. Amended and Restated 2018 Omnibus Incentive Plan (the “2018 Incentive Plan”) and no further awards will be issued under the 2018 Incentive Plan. The 2026 Incentive Plan authorizes one million three hundred twenty-one thousand (1,321,000) shares of ICF International common stock for issuance. Detailed information on Proposal 3 can be found on pages 16 through 24 in this Proxy Statement and a copy of the ICF International, Inc. 2026 Incentive Plan is attached as Exhibit A to this Proxy Statement.

The Board voted to approve the adoption of the 2026 Incentive Plan on April 8, 2026. If our stockholders vote to approve the 2026 Incentive Plan at the Annual Meeting, the plan will become effective upon such approval.

Detailed information on Proposal 3 can be found on pages 16 through 24 in this Proxy Statement and a copy of the ICF International, Inc. 2026 Incentive Plan is attached as Exhibit A to this Proxy Statement.

RATIFY THE SELECTION OF GRANT THORNTON LLP AS OUR INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM FOR FISCAL YEAR 2026 (PROPOSAL 4)

The Audit Committee has appointed, and the Board has approved the appointment of, Grant Thornton as the Company’s independent registered public accounting firm (the “independent auditor”) for the fiscal year ending December 31, 2026. While we are not required to have stockholders ratify the selection of Grant Thornton as the Company’s independent auditor, we are doing so because, among other reasons, we believe it is good corporate governance practice. If stockholders do not ratify the selection, the Audit Committee will reconsider

the appointment but may nevertheless retain Grant Thornton as the Company’s independent auditor. Even if the selection is ratified, the Audit Committee may, at its discretion, direct the appointment of a different independent auditor at any time during the year if it determines that such change is in the best interests of the Company and its stockholders.

SUBMISSION OF STOCKHOLDER PROPOSALS OR NOMINATIONS FOR 2027 ANNUAL MEETING OF STOCKHOLDERS

Stockholder proposals submitted for inclusion in our 2027 proxy statement pursuant to Rule 14a-8 (“Rule 14a-8”) under the Securities Exchange Act of 1934, as amended (the “Exchange Act”), must be received by us by December 24, 2026. Notice of stockholder proposals to nominate a person for election as a director or to introduce an item of business at the 2027 annual meeting of stockholders outside Rule 14a-8 must be received by us no earlier than February 2, 2027, and no later than March 4, 2027.

In addition to complying with the procedures described above, stockholders who intend to solicit proxies in support of a director nominee other than the Company’s nominees for consideration by the stockholders at the Company’s 2027 annual meeting of stockholders must also comply with the SEC’s “universal proxy card” rules under Rule 14a-19 of the Exchange Act (“Rule 14a-19”). Rule 14a-19 requires proponents to provide a notice to the Corporate Secretary of the Company, no later than April 5, 2027, setting forth all of the information and disclosures required by Rule 14a-19. If the 2027 annual meeting of stockholders is set for a date that is not within thirty (30) calendar days of the anniversary of the date of the 2026 Annual Meeting of Stockholders, then notice must be provided by the later of sixty (60) calendar days of the anniversary of the date of the 2026 Annual Meeting of Stockholders or by the close of business on the tenth (10 th) calendar day following the day on which a public announcement of the date of the 2027 annual meeting of stockholders is first made.

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