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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:

CLEAN ENERGY FUELS CORP.

(Name of Registrant as Specified in its Charter)

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(Name of Person(s) Filing Proxy Statement, if Other Than the Registrant)

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

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CLEAN ENERGY FUELS CORP.

4675 MacArthur Court, Suite 800

Newport Beach, California 92660

April 30, 2026

Dear Stockholder,

You are cordially invited to attend the annual meeting of stockholders (“Annual Meeting”) of Clean Energy Fuels Corp. (the “Company,” “Clean Energy,” “we,” “us” or “our”) on Wednesday, June 10, 2026, at 9:00 a.m. Pacific Time. The Annual Meeting will be a virtual meeting conducted via live audio webcast that can be accessed by visiting www.virtualshareholdermeeting.com/CLNE2026. At this website, you will be able to listen to the Annual Meeting live, submit questions for our management, directors and representatives of our independent registered public accounting firm in attendance, and submit your vote while the Annual Meeting is being held.

I’m honored to be writing to you for the first time as Clean Energy’s chief executive officer. But I’m no stranger having been with the company for close to two decades. My goal as the incoming CEO is to focus on growing the company, using new technologies to find new customers and markets, engage with those customers, drive efficiencies and leverage the investments we’ve already made.

As we look back on 2025, it is clear that Clean Energy’s strategy and long-term investments continue to position us at the center of one of the most compelling transitions happening in transportation today. The momentum we’ve built across our renewable natural gas (“RNG”) production projects, fueling network, and customer base advanced significantly, and we closed 2025 stronger, more resilient, and more prepared for the growth ahead.

We now have eight dairy RNG projects in operation, along with three more in construction and development, each adding meaningful long term value to our RNG production portfolio. The completion of our South Fork Dairy project in Texas in 2025, now one of the largest RNG facilities in the country, was a huge milestone we crossed. South Fork is capable of producing 2.6 million gallons of low carbon-intensity transportation fuel annually, helping us continue to supply our network of stations and fleet customers.

The year also marked the successful monetization of $29.5 million in investment tax credits (“ITC”), the third ITC transaction tied to our RNG projects as part of our joint venture with bp. With this sale, all ITC credits across all six dairy RNG facilities have now been fully realized, reinforcing the value of these projects and strengthening the cash flow profile of our portfolio.

While our own RNG facilities continue to play an important role in supplying our network, they make up a portion of the fuel delivered across our stations. On the fuel supply side, we delivered 237 million gallons of RNG in 2025. To continue to support growing fleet demand, we draw from a broad, nationwide pool of producers, giving us access to diverse and reliable volumes of RNG from dairy, swine and landfill origins.  

Our expansive fueling footprint remains an attractive outlet for RNG producers, as transportation use generates the strongest value for the fuel. As we grow, we remain disciplined in balancing the benefits of developing new projects with the flexibility that also comes from procuring RNG.

On the heavy duty trucking side of things, no segment of the transportation market is undergoing more rapid change, and 2025 was a milestone year on this front. The introduction of the Cummins X15N engine continued to energize the market.

Building on the success of our initial demonstration truck program from the year prior, we launched a second program featuring the Freightliner Cascadia tractor equipped with the X15N. Interest from fleets was strong, feedback and reviews are positive with many praising their firsthand experiences running heavy loads powered by RNG, while they continue to evaluate long-term alternatives to diesel. The combination of X15N performance and RNG’s carbon and cost advantages is resonating with major carriers nationwide.

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We are also seeing rising demand across our transit and refuse customer base, who continue to adopt RNG not only as a means to decarbonize, but because it aligns with both budget and operational needs. In 2025, we secured more than a dozen new RNG supply agreements, adding over 10 million gallons of annual demand, while contracting 16 new stations and renewing long‑term supply at 17 existing locations. Combined, these commitments represent more than 30 million gallons of yearly fuel consumption and highlight the strength and staying power of our transit and refuse business.

As we look ahead, the opportunity in front of us is substantial. More fleets are acting now rather than waiting for alternative technologies that remain years from commercial viability. This aligns squarely with Clean Energy’s strategy: continue expanding our RNG supply, grow our customer base, and optimize the nation’s most extensive RNG fueling network. We are a unique company in that we provide a product to customers and to their customers that does good for the world. As I write this, traditional energy markets are being rocked by global events. But RNG is a domestic fuel that is not impacted by that. It also reduces harmful emissions, which we all care about.  

Our development pipeline is active, our operational base is stronger than ever, and our ability to supply meaningful volumes of RNG, both produced and procured, is unmatched. With each new project, each new fleet deployment, and each gallon of RNG delivered, we strengthen our leadership position in the clean transportation market.

We are pleased to take advantage of laws and rules that allow issuers to make use of the Internet in conducting a meeting of stockholders, as well as in furnishing proxy materials. As a result, we will not only host the Annual Meeting virtually on the Internet, but we will also furnish the proxy materials for the Annual Meeting to our stockholders on the Internet. We believe this use of the Internet meaningfully lowers our costs, increases efficiencies and helps reduce the environmental impact of the Annual Meeting, while permitting and encouraging increased stockholder attendance and engagement.

The accompanying notice of Annual Meeting and Proxy Statement include the agenda for the Annual Meeting, explain the matters that will be discussed and voted on at the Annual Meeting and provide certain other information about our Company.

Your vote is important, and we urge you to vote as promptly as possible. Thank you for supporting our Company.

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CLEAN ENERGY FUELS CORP.

4675 MacArthur Court, Suite 800

Newport Beach, California 92660

NOTICE OF ANNUAL MEETING OF STOCKHOLDERS

June 10, 2026

The annual meeting of stockholders (“Annual Meeting”) of Clean Energy Fuels Corp. (the “Company,” “we,” “us” or “our”) will be held on Wednesday, June 10, 2026, at 9:00 a.m. Pacific Time via live audio webcast that can be accessed by visiting www.virtualshareholdermeeting.com/CLNE2026, for the following purposes:

The foregoing items of business are more fully described in the Proxy Statement that accompanies this notice.

The Company’s Board of Directors has fixed the close of business on April 16, 2026 as the record date for the determination of stockholders entitled to notice of and to vote at the Annual Meeting and any adjournment or postponement thereof. A list of stockholders entitled to vote at the Annual Meeting will be available for inspection by any stockholder for any purpose germane to the Annual Meeting at our principal executive offices during normal business hours for a period of 10 days before the Annual Meeting. The list of stockholders may also be accessed during the virtual Annual Meeting at www.virtualshareholdermeeting.com/CLNE2026 by using the control number on your proxy card, voting instruction form or Notice of Internet Availability.

Even if you plan to attend the Annual Meeting, you are encouraged to vote on the Internet, by telephone or by mail before the Annual Meeting using the instructions provided in the accompanying proxy materials to ensure that your vote will be counted. If you submit your proxy or voting instructions and then decide to attend the Annual Meeting, you may still vote your shares during the Annual Meeting.

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CLEAN ENERGY FUELS CORP.

4675 MacArthur Court, Suite 800

Newport Beach, California 92660

2026 PROXY STATEMENT

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CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS

This Proxy Statement includes forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. Forward-looking statements are statements other than historical facts and relate to future events or circumstances or our future performance, and are based on our current assumptions, expectations and beliefs concerning future developments and their potential effect on our Company and our business. Forward-looking statements included herein include but are not limited to: statements about our Company’s position in the RNG market, our expectations regarding our dairy RNG projects and anticipated RNG facilities, the benefits of the Cummins X15N engine, and statements about our leadership transition and our position as a leading renewable energy company. Actual results, performance or achievements and the timing of events could differ materially from those anticipated in or implied by these forward-looking statements as a result of many factors, including, among others: the willingness of fleets and other consumers to adopt natural gas as a vehicle fuel, and the rate and level of any such adoption; the market’s perception of the benefits of RNG and conventional natural gas relative to other alternative vehicle fuels; natural gas vehicle and engine cost, fuel usage, availability, quality, safety, convenience, design, performance and residual value, as well as operator perception with respect to these factors, in general and in our key customer markets, including heavy-duty trucking; our ability to further develop and manage our RNG business, including our ability to procure adequate supplies of RNG and generate revenues from sales of such RNG; our and our suppliers’ ability to successfully develop and operate projects and produce expected volumes of RNG; the impact of a bankruptcy or failure of any source owners at our projects; our dependence on the production of vehicles and engines by manufacturers over which the we have no control; the long and variable development cycle required to secure anaerobic digester gas (“ADG”) RNG from new projects; the potential commercial viability, solvency, financial capacity, and operational capability of livestock waste and dairy farm projects to produce RNG; our history of net losses and the possibility that we could incur additional net losses in the future; our and our partners’ ability to acquire, finance, construct and develop other commercial projects; our ability to invest in hydrogen stations or modify our fueling stations to reform our RNG to fuel hydrogen and charge electric vehicles; the future supply, demand, use and prices of crude oil, gasoline, diesel, natural gas, and other vehicle fuels, including overall levels of and volatility in these factors; changes in the competitive environment in which we operate, including potentially increasing competition in the market for vehicle fuels generally; our ability to manage and increase our business of transporting and selling CNG (as defined below) for non-vehicle purposes via virtual natural gas pipelines and interconnects, as well as our station design and construction activities; construction, permitting and other factors that could cause delays or other problems at station construction projects; our ability to procure and maintain contracts with government entities; our ability to execute and realize the intended benefits of any acquisitions, divestitures, investments or other strategic relationships or transactions; significant fluctuations in our results of operations, which make it difficult to predict future results of operations; our warranty reserves may not adequately cover our warranty obligations; a future pandemic, epidemic or other infectious disease outbreak; the future availability of and our access to additional capital, which may include debt or equity financing, in the amounts and at the times needed to fund growth in our business and the repayment of our debt obligations (whether at or before their due dates) or other expenditures, as well as the terms and other effects of any such capital raising transaction; our ability to generate sufficient cash flows to repay our debt obligations as they come due; the availability of environmental, tax and other government legislation, regulations, programs and incentives that promote natural gas, including long-standing support for gasoline- and diesel-powered vehicles and growing support for electric and hydrogen-powered vehicles that could result in programs or incentives that favor these or other vehicles or vehicle fuels over natural gas; our ability to comply with various registration and regulatory requirements related to its RNG projects; the effect of, or potential for changes to greenhouse gas emissions requirements or other environmental regulations applicable to vehicles powered by gasoline, diesel, natural gas or other vehicle fuels and crude oil and natural gas fueling, drilling, production, transportation or use; our ability to manage the health, safety and environmental risks inherent in its operations; our compliance with all applicable government and environmental regulations; the impact of the foregoing on the trading price of our common stock; the interests of our significant stockholders may differ from our other stockholders; our ability to protect against any material failure, inadequacy, interruption or security failure of our information technology; general political, regulatory, economic and market conditions; and the other risks and uncertainties set forth under Item 1A, Risk Factors in our Annual Report on Form 10-K for the year ended December 31, 2025 that we filed with the Securities and Exchange Commission (“SEC”) and that accompanies this Proxy Statement, as such risk factors may be amended, supplemented or superseded from time to time by other reports we file with the SEC. We encourage you to carefully consider these risks and uncertainties. The forward-looking statements made in this Proxy Statement speak only as of the date of this Proxy Statement and we undertake no obligation to update publicly such forward-looking statements to reflect subsequent events or circumstances, except as otherwise required by law.

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WEBSITE REFERENCES

Throughout this Proxy Statement, we make references to additional information available on our corporate website at www.cleanenergyfuels.com. References to our website are provided for convenience only and the content on our website does not constitute a part of this Proxy Statement.

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CLEAN ENERGY FUELS CORP.

4675 MacArthur Court, Suite 800

Newport Beach, California 92660

2026 PROXY STATEMENT

GENERAL INFORMATION

The board of directors (“Board”) of Clean Energy Fuels Corp., a Delaware corporation (the “Company,” “we,” “us” or “our”), is providing this Proxy Statement (“Proxy Statement”) and all other proxy materials to you in connection with the solicitation of proxies for use at our 2026 annual meeting of stockholders (“Annual Meeting”). The Annual Meeting will be held on Wednesday, June 10, 2026, at 9:00 a.m. Pacific Time (“PT”) via live audio webcast that can be accessed by visiting www.virtualshareholdermeeting.com/CLNE2026 for the purposes stated in this Proxy Statement. In addition to any other business that may properly come before the Annual Meeting or any adjournment or postponement thereof, stockholders are being asked to vote at the Annual Meeting on the following three proposals:

This Proxy Statement summarizes the information you need to know in order to vote on these proposals in an informed manner.

IMPORTANT NOTICE REGARDING THE AVAILABILITY OF PROXY MATERIALS

The Notice of Annual Meeting, Proxy Statement and our 2025 Annual Report on Form 10-K (“Annual Report”) are available at www.proxyvote.com. You are encouraged to access and review all of the important information contained in our proxy materials before voting. Copies of these proxy materials are also available in the Investors — SEC Filings section of our website at https://investors.cleanenergyfuels.com/sec-filings/all-sec-filings.

Use of the Internet

Pursuant to rules adopted by the SEC, we have elected to provide access to our proxy materials for the Annual Meeting, including this Proxy Statement and our Annual Report, on the Internet. Accordingly, on or about April 30, 2026, we are mailing a Notice of Internet Availability of Proxy Materials (“Notice”) to all of our stockholders of record who have not previously elected an alternative delivery method, while brokers, banks and other nominees who hold shares on behalf of beneficial owners will be sending their own similar Notice to beneficial owners. The Notice will include instructions on how you may access the proxy materials for the Annual Meeting at www.proxyvote.com. For stockholders who have previously elected to receive copies of the proxy materials by mail or e-mail, we will be sending the Annual Report, this Proxy Statement and a proxy card by that method on or about April 30, 2026. Stockholders who receive a Notice will not receive printed copies of the proxy materials for the Annual Meeting unless they request them, in which case printed copies of the proxy materials and a paper proxy card will be provided at no charge. Instructions on how to request a printed copy of the proxy materials by mail or electronically, including an option to request paper copies on an ongoing basis, may be found in the Notice and on the website referred to in the Notice. We encourage you to take advantage

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of the availability of our proxy materials on the Internet in order to lower our printing and delivery costs and help reduce the environmental impact of the Annual Meeting.

Virtual Annual Meeting

We will be holding the Annual Meeting virtually on the Internet via live audio webcast. No physical meeting will be held. Stockholders who attend the Annual Meeting virtually will be able to listen to the meeting live and submit their vote while the Annual Meeting is being held, and will also be able to submit, either anonymously or identified by name, questions or comments for our management, directors and representatives of our independent registered public accounting firm in attendance at the meeting. This functionality provides our stockholders with opportunities for participation and engagement at the Annual Meeting that are comparable to those that would be available at an in-person meeting.

During the Annual Meeting, we will answer as many stockholder-submitted questions as time permits, other than questions that are irrelevant to the purpose of the Annual Meeting or our business or that contain inappropriate or derogatory references.

Stockholders who choose to attend the Annual Meeting will do so by accessing a live audio webcast of the Annual Meeting via the Internet at www.virtualshareholdermeeting.com/CLNE2026. Please see “Attending the Virtual Annual Meeting” below for more information.

Record Date and Outstanding Shares

All stockholders that owned shares of our common stock at the close of business on April 16, 2026 (the “Record Date”), the date fixed by our Board as the record date, are entitled to vote at the Annual Meeting.

On the Record Date, 220,224,634 shares of our common stock were outstanding.

Voting Matters

Voting Rights

Each share of our common stock entitles the owner of the share to one vote for each share of common stock held by such owner on all matters to be voted on at the Annual Meeting.

Quorum Requirement

We will have the required quorum to conduct the business of the Annual Meeting if holders as of the Record Date representing a majority of the outstanding shares of our common stock entitled to vote are present in person or represented by proxy at the Annual Meeting. Abstentions and broker non-votes (discussed under “Effect of Not Providing Voting Instructions; Broker Non-Votes” below) will be counted for purposes of determining the presence of a quorum at the Annual Meeting.

Effect of Not Providing Voting Instructions; Broker Non-Votes

Stockholders of Record. You are a “stockholder of record” if your shares are registered directly in your name with Computershare Trust Company, N.A., our transfer agent. If you were a stockholder of record at the close of business on the Record Date and you submit a valid proxy but do not provide voting instructions with respect to your shares, all shares represented by your proxy will be voted in accordance with the recommendation of our Board on each proposal to be presented at the Annual Meeting, as described in this Proxy Statement.

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Beneficial Owners of Shares Held in Street Name. You are a “beneficial owner of shares held in street name” if your shares are not held of record in your name but are held by a broker, bank or other nominee on your behalf as the beneficial owner. Pursuant to applicable stock exchange rules, if your shares were held in street name through a brokerage account at the close of business on Record Date, you must provide voting instructions to your broker if you want your shares to be voted on the election of directors (Proposal 1) and on the approval, on an advisory, non-binding basis, of the compensation of our named executive officers (Proposal 3). These proposals constitute “non-routine” matters on which a broker is not entitled to vote shares held for a beneficial owner without receiving voting instructions from the beneficial owner. The ratification of the appointment of KPMG LLP as our independent registered public accounting firm (Proposal 2) is considered a “routine” matter for which your shares may be voted in the discretion of your broker if voting instructions have not been received. As a result, if you hold your shares in street name and you do not submit voting instructions to your broker, your broker may exercise its discretion to vote on Proposal 2 at the Annual Meeting but will not be permitted to vote on Proposal 1 or Proposal 3 at the Annual Meeting. If your broker does not exercise this discretion, your shares might not be voted. Consequently, we urge every stockholder to vote their shares. If your broker does exercise this discretion, your shares will be counted as present for determining the presence of a quorum at the Annual Meeting and will be voted on Proposal 2 in the manner directed by your broker, but your shares will constitute “broker non-votes” on each of the other items at the Annual Meeting. Moreover, if you are a beneficial owner of shares in street name and you properly submit a voting instruction form to your broker, bank or other nominee that is signed but unmarked with respect to your vote on Proposals 1, 2, or 3, applicable rules will generally permit your broker, bank or other nominee to vote your shares on these proposals in accordance with the recommendations of our Board as set forth in this Proxy Statement.

Voting Requirements

The election of directors (Proposal 1) will be determined by a plurality of the votes cast on the proposal at the Annual Meeting. This means that the six nominees who receive the highest number of affirmative votes will be elected as directors. Shares voted “Withhold” and broker non-votes are not counted as votes cast and will have no effect on the outcome of the election of directors.

The ratification of the appointment of KPMG LLP as our independent registered public accounting firm (Proposal 2) and the approval, on an advisory, non-binding basis, of the compensation of our named executive officers (Proposal 3), must each be approved by the affirmative vote of a majority of the votes cast on the proposal at the Annual Meeting. For purposes of determining the number of votes cast for Proposals 2 and 3, only shares voted “FOR” or “AGAINST” are counted. Abstentions and broker non-votes are not treated as votes cast and will not be counted in determining the outcome of Proposals 2 or 3.

The following is a summary of the voting requirements for each proposal to be voted on at the Annual Meeting:

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Tabulation of Votes

The inspector of elections of the Annual Meeting will tabulate the votes of our stockholders at the Annual Meeting. All shares of our common stock represented by proxy at the Annual Meeting will be voted in accordance with the instructions given on the proxy, as long as the proxy is properly submitted and unrevoked and is received by the applicable deadline, all as described under “How to Cast or Revoke Your Vote” below. If the Annual Meeting is adjourned or postponed, properly submitted and unrevoked proxies will remain effective and will be voted at the adjourned or postponed Annual Meeting, and stockholders will retain the right to revoke any such proxy until it is actually voted at the adjourned or postponed Annual Meeting.

Voting Results

Preliminary results will be announced at the Annual Meeting. Final results will be reported in a Current Report on Form 8-K to be filed with the SEC within four business days after the Annual Meeting concludes. If the official results are not available at that time, we will provide preliminary voting results in such Form 8-K and will provide the final results in an amendment to the Form 8-K as soon as they become available.

How to Cast or Revoke Your Vote

Stockholders of Record

If you are a stockholder of record entitled to vote at the Annual Meeting, you may vote in any one of the following ways:

Votes submitted by proxy on the Internet or by telephone must be received by 11:59 p.m. Eastern Time on Tuesday, June 9, 2026 to be counted. Votes submitted on the Internet during the Annual Meeting by stockholders attending the meeting and votes submitted by mail must be received no later than the close of voting at the Annual Meeting to be counted.

Once you have submitted your proxy on the Internet or by telephone or mail, you may revoke it at any time before it is voted at the Annual Meeting by taking any one of the following actions:

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To be effective, any later-dated vote must be received by the applicable deadline for the voting method used, as described above, and any written notice of revocation must be received no later than the close of voting at the Annual Meeting. Only your latest-dated vote that is received by the deadline applicable to the voting method used will be counted.

Beneficial Owners of Shares Held in Street Name

If you are a beneficial owner of shares held in street name, you have the right to instruct your broker, bank or other nominee on how to vote your shares at the Annual Meeting. You should do so by following the instructions provided by your broker, bank or other nominee regarding how to vote your shares and how to revoke a previously submitted proxy. The availability of Internet, telephone or other methods to vote your shares by proxy, and the deadlines by which to vote your shares using each such voting method, will depend on the voting processes of the broker, bank or other nominee that holds your shares.

Attending the Virtual Annual Meeting

All stockholders that owned our common stock at the close of business on the Record Date, or their duly appointed proxies, may attend and participate in the Annual Meeting. Even if you plan to attend the Annual Meeting, you are encouraged to vote on the Internet, by telephone or by mail before the Annual Meeting, to ensure that your vote will be counted. Please see “How to Cast or Revoke Your Vote” above.

To attend and participate in the Annual Meeting, stockholders will need to access the live audio webcast of the meeting. To do so, stockholders of record will need to visit www.virtualshareholdermeeting.com/CLNE2026 and use their control number provided in the Notice or, if they received printed copies of the proxy materials, in the proxy card delivered with those proxy materials, to log in to this website, and beneficial owners of shares held in street name will need to follow the instructions provided by the broker, bank or other nominee that holds their shares. On the day of the Annual Meeting, stockholders may begin to log in to the virtual meeting beginning at 8:45 a.m. PT, and the meeting will begin promptly at 9:00 a.m. PT. We encourage stockholders to log in to this website and access the webcast before the Annual Meeting’s start time. Further instructions on how to attend, participate in and vote at the Annual Meeting are available at www.proxyvote.com. If you encounter any difficulties accessing or logging in to the Annual Meeting, including any difficulties with your control number or submitting questions, please call the technical support number displayed on the login page on the online virtual meeting platform.

Submitting your proxy before the Annual Meeting will not affect your right to vote at the Annual Meeting if you decide to attend; however, your attendance at the Annual Meeting after having submitted a valid proxy will not in and of itself constitute a revocation of your proxy. To revoke a previously submitted proxy by attending the Annual Meeting, you must submit an online vote during the webcast of the Annual Meeting reflecting your new vote.

Solicitation

This solicitation is made by our Board, and we will bear the entire cost of soliciting proxies, including the costs of preparing, printing, assembling and mailing the Notice, any printed copies of this Proxy Statement, the proxy card, the Annual Report, and any additional information that we may elect to furnish to stockholders. We will provide copies of solicitation materials to brokers, banks and other nominees holding in their names shares of our common stock that are beneficially owned by others for forwarding to the beneficial owners of those shares who have requested printed materials, and we may reimburse persons representing beneficial owners for their costs of forwarding solicitation materials to the beneficial owners. Solicitations will be made primarily through the Notice and the solicitation materials made available on the Internet or via e-mail or in print to those who request copies of our proxy materials, but may be supplemented by telephone, mail, e-mail or personal solicitation by our directors, executive officers or other employees. We will pay no additional compensation to these individuals for these activities. We have not engaged employees for the specific purpose of soliciting proxies.

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Separate Copy of Annual Report or Other Proxy Materials

We have adopted a procedure called “householding,” which the SEC has approved. Under this procedure, we are delivering a single copy of this Proxy Statement and our Annual Report to multiple stockholders who share the same address and who did not receive a Notice or otherwise receive their proxy materials by e-mail, unless we have received contrary instructions from a stockholder. This procedure reduces our printing and mailing costs and other fees. Stockholders who participate in householding will continue to be able to request and receive a separate Notice or proxy card. Additionally, upon written or oral request, we will deliver promptly a separate copy of this Proxy Statement or the Annual Report to any stockholder at a shared address to which we have delivered a single copy of these documents. To receive a separate copy of this Proxy Statement or the Annual Report, or to notify us that you wish to receive separate copies of our proxy materials for future annual meetings of our stockholders, write to the attention of Investor Relations at our principal executive offices at 4675 MacArthur Court, Suite 800 Newport Beach, California 92660, or call (949) 437-1000. Stockholders who share an address and are receiving multiple copies of our proxy materials may also request to receive a single copy of this Proxy Statement and the Annual Report or our proxy materials for future annual meetings of our stockholders by writing or calling us at the address or telephone number provided above.

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SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

The two tables below show the beneficial ownership of certain persons with respect to our common stock, our only outstanding class of voting securities. Except as indicated by the footnotes to these tables, we believe, based on the information furnished or otherwise available to us, that the persons and entities named in these tables have sole voting and investment power with respect to all shares of common stock shown as beneficially owned by them, subject to applicable community property laws.

We have determined beneficial ownership as shown in these tables in accordance with the rules of the SEC. In accordance with these rules, in computing the number of shares of our common stock beneficially owned by a person and the percentage ownership of that person, we deemed to be outstanding all shares of our common stock subject to (1) stock options held by that person that are currently exercisable or exercisable within 60 days after April 16, 2026, and (2) restricted stock units (“RSUs”) held by that person that are subject to vesting and settlement within 60 days after April 16, 2026. We did not, however, deem these shares outstanding for the purpose of computing the percentage ownership of any other person. We calculated percentage ownership as shown in these tables based on 220,224,634 shares of our common stock outstanding on April 16, 2026. The information in these tables is not necessarily indicative of beneficial ownership for any other purpose, and the inclusion of any shares in these tables does not constitute an admission of beneficial ownership of the shares.

The following table shows the amount and percentage of our common stock beneficially owned by each holder of more than 5% of the outstanding shares of our common stock:

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as of October 13, 2025. According to the Schedule 13G, the Stonepeak Investors have shared voting power and shared dispositive power with respect to 20,050,618 shares of our common stock that were purchased by Stonepeak CLNE-W Holdings LP pursuant to a warrant agreement dated December 12, 2023, between Stonepeak CLNE-W Holdings LP and our Company, that became exercisable by Stonepeak CLNE-W Holdings LP on December 12, 2025.

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The following table shows the amount and percentage of our common stock beneficially owned on April 16, 2026 by each of our named executive officers and current directors and by all of our current executive officers and current directors as a group:

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PROPOSAL 1

ELECTION OF DIRECTORS

General

Upon the recommendation of our nominating and corporate governance committee, our Board nominated our current directors Barclay F. Corbus, Andrew J. Littlefair, Stephen A. Scully, Lizabeth A. Ardisana, Patrick J. Ford, and Vincent C. Taormina, for election as members of our Board at the Annual Meeting. As disclosed in our Current Report on Form 8-K filed on April 23, 2026, on April 22, 2026 our Board, based on the recommendation of our nominating and corporate governance committee, appointed Mr. Corbus as a director in connection with our Company’s Chief Executive Officer Transition. Mr. Corbus will be standing for election to our Board for the first time at the Annual Meeting. Each of our director nominees, other than Messrs. Corbus and Littlefair, are independent directors within the meaning of applicable rules of The Nasdaq Stock Market LLC (“Nasdaq”). Each of the nominees is a current director of our Company and, other than Mr. Corbus, was elected by our stockholders at our 2025 annual meeting of stockholders.

Upon election at the Annual Meeting, each director will serve a one-year term until the next annual meeting of our stockholders and until his or her respective successor is duly elected and qualified or until his or her earlier resignation or removal. Each of our Board’s director nominees has agreed to serve if elected, and, as of the date of this Proxy Statement, we have no reason to believe any nominee will be unable or unwilling to serve as a director if elected. If, however, any nominee is unable to serve, or for good cause will not serve, as a director at the time of the Annual Meeting, the persons who are designated as proxies may vote your shares, in their discretion, for another nominee that may be proposed by our Board or our Board may choose to reduce the size of the Board.

We, as a matter of policy, encourage our directors to attend meetings of our stockholders and, in 2025, all of our then-current directors attended our annual meeting of stockholders.

Director Nominees

The names of the director nominees, their ages as of the date of this Proxy Statement, their current positions and offices with our Company and other information about their professional backgrounds are shown below. We believe each of these nominees contributes to our Board’s effectiveness as a whole based on the wealth of executive leadership experience they bring to our Board, as well as the other specific attributes, qualifications and skills described below. There are no family relationships between any director, executive officer or person nominated or chosen to become a director or executive officer of our Company, and there are no arrangements or understandings between any director or nominee and any other person pursuant to which such individual was or is selected as a director or nominee.

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Barclay F. Corbus has served as our President, Chief Executive Officer and a director since April 22, 2026. Previously, Mr. Corbus served as our Senior Vice President, Strategic Development and Head of Renewable Fuels from December 2021 to April 22, 2026. Prior to that, Mr. Corbus served as our Senior Vice President, Strategic Development from September 2007 to December 2021. From July 2003 to September 2007, Mr. Corbus served as Co-Chief Executive Officer and a director of WR Hambrecht + Co, an investment bank that managed our initial public offering. Mr. Corbus joined WR Hambrecht + Co in 1999 and, from October 2000 to July 2003, Mr. Corbus served as Head of Investment Banking of WR Hambrecht + Co. From 1989 to 1999, Mr. Corbus worked with Donaldson, Lufkin & Jenrette. Mr. Corbus serves as a director of Bed Bath & Beyond, Inc., a publicly traded company, since March 2007 and is a Trustee of the College of the Atlantic. He has previously served on the boards of Alaska Energy and Resources Co, WR Hambrecht +

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Co., Niman Ranch, and Goodwill of San Francisco. Mr. Corbus earned an B.A. in government from Dartmouth College and an M.B.A from Columbia Business School.

Skills and Qualifications: Mr. Corbus brings to our Board his nineteen years of experience at the Company in senior executive positions leading corporate strategy, M&A and financing activities, as well as our growing RNG production and distribution businesses, which gives him unique insight into our Company’s operations, challenges, and opportunities.

Stephen A. Scully has served as a director of our Company since January 2014 and was appointed Chairman of the Board effective January 1, 2018. Mr. Scully was the founder and President of The Scully Companies, a California-based full service truck leasing and specialized contract carriage provider. He founded The Scully Companies in 1981 after graduating from the University of Southern California and subsequently sold the business to Ryder System, Inc. in January 2011. The Scully Companies was the largest independent asset-based logistics provider in the western United States. Since selling The Scully Companies, Mr. Scully has been a private investor and has served on the Newport Beach Harbor Commission since 2009, including two terms as Chairman. Mr. Scully previously served as a board member and two terms as Chairman of the Board of National Truck Leasing System from 1999 to 2010, as a board member of the Truck Rental and Leasing Association from 1990 to 1999, and as a board member of Ameriquest Transportation and Logistics Resources from 2007 to 2008. He is a former member of the California Trucking Association.  

Skills and Qualifications:  Mr. Scully brings to our Board the perspective of a founder and operator, along with extensive experience in the trucking and logistics industry and public-company board leadership.

Lizabeth A. Ardisana has served as a director of our Company since December 2019. Ms. Ardisana is the Chief Executive Officer and the Principal Owner of the firm ASG Renaissance, LLC, which she founded in 1987. ASG Renaissance is a technical and communication services firm with experience providing services to clients in the automotive, environmental, defense, construction, healthcare, banking, and education sectors. Ms. Ardisana is also Chief Executive Officer of Performance Driven Workforce, LLC, a scheduling and staffing firm that was founded in 2015 and has since expanded into five states. Ms. Ardisana, a Hispanic and female business owner, is an active business and civic leader in Michigan. Ms. Ardisana has held numerous leadership positions in a variety of non-profit organizations, including CS Mott Foundation, Kettering University, Metropolitan Affairs Coalition and Focus: Hope. She was appointed by the governor of Michigan to the executive board of the Michigan Economic Development Corporation and serves on its finance committee. Ms. Ardisana is also vice chair of Wayne Health where she serves on the audit committee. On October 10, 2022, Ms. Ardisana was appointed to the Board of Directors of Hannon Armstrong Sustainable Infrastructure Capital, Inc., a leading investor in climate solutions. She previously served as a member of the board of directors of LeddarTech Holdings Inc., a publicly traded company, from January 2024 to June 2025, Huntington Bancshares Inc., a publicly traded company, from 2016 to 2023 and as a member of the board of directors of FirstMerit Corporation from 2013 to 2016. Ms. Ardisana previously served as a board member of United Way for Southeastern Michigan (where she served as chair) and the Skillman Foundation. Ms. Ardisana holds a bachelor’s degree in mathematics and computer science from the University of Texas, a master’s degree in Mechanical Engineering from the University of Michigan and a master’s degree in Business Administration from the University of Detroit.

Skills and Qualifications: Ms. Ardisana brings to our Board key experience and relationships in the automotive and environmental industries, as well as skills acquired through serving as a chief executive officer and as a member of multiple public and private company boards.

Patrick J. Ford has served as a director of our Company since March 2024. Mr. Ford served as an Audit Partner at KPMG LLP, an accounting and advisory firm, from 1994 until his retirement in 2022. Mr. Ford served numerous SEC registrants as the Lead Audit Engagement Partner in the energy, automotive and technology sectors during his tenure with KPMG LLP. Mr. Ford served as a member of the Board of Directors of KPMG LLP and its related entity, KPMG Americas LLP from 2013 to 2018. Mr. Ford is a certified public accountant (retired status) in California. Since 2025, Mr. Ford has served on The Board of Directors of Claremont Lincoln University and previously served on the Board of Advisors for the University of Southern California Marshall School of Business from 2006 to 2019 and the Board of Advisors for the Shidler School of Business at the University of Hawaii at Manoa from 2003 to 2007. Mr. Ford holds a bachelor’s degree in business administration with an emphasis in accounting from the University of Southern California.

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Skills and Qualifications: Mr. Ford brings to our Board extensive experience in finance and accounting within the energy industry.

Andrew J. Littlefair, one of our founders, has served as a director since June 2001. Previously, Mr. Littlefair served as our President and Chief Executive Officer from June 2001 to April 22, 2026. From 1996 to 2001, Mr. Littlefair served as President of Pickens Fuel Corp., and from 1987 to 1996, Mr. Littlefair served in various management positions at Mesa, Inc., an energy company. From 1983 to 1987, Mr. Littlefair served in the Reagan Administration as a Staff Assistant to the President. Mr. Littlefair served as the chairman of the board of directors of SAFE S.p.A. and also served on the board of directors of Hilltop Holdings Inc. (formerly PlainsCapital Corporation), a reporting company under the Securities Exchange Act of 1934, as amended (“Exchange Act”), from 2009 to 2023. Mr. Littlefair served as Chairman of NGV America, the leading U.S. advocacy group for natural gas vehicles, from March 2003 to March 2011. He has served on the Ronald Reagan Presidential Foundation & Institute Board of Trustees since July 2011. Mr. Littlefair earned a B.A. from the University of Southern California.

Skills and Qualifications: Mr. Littlefair brings to our Board his experience as a co-founder and as the former President and Chief Executive Officer of our Company, which gives him unique insight into our Company’s operations, challenges and opportunities.

Vincent C. Taormina has served as a director of our Company since April 2008. Mr. Taormina is the former Chief Executive Officer of Taormina Industries, Inc., one of California’s largest solid waste and recycling companies. In 1997, Taormina Industries, Inc. merged with Republic Services, a publicly-held waste handling company that operates throughout the United States. Mr. Taormina served as Regional Vice President of Republic Services from 1997 to 2001, managing the overall operations of eleven western states. Since 2001, Mr. Taormina has served and continues to serve as a consultant to Republic Services and is a private investor. Mr. Taormina is a past President of the Orange County Solid Waste Management Association, past President Elect of the California Refuse Removal Council and a former board member of the Waste Recyclers Council for the National Solid Waste Management Board.

Skills and Qualifications: Mr. Taormina brings to our Board the perspective of a highly successful entrepreneur and industry leader in the refuse and recycling industry.

Selecting Our Director Nominees

Under its charter and our corporate governance guidelines, our nominating and corporate governance committee is responsible for reviewing with our Board, on an annual basis, the requisite skills and characteristics of potential new Board members, as well as the composition of our Board as a whole. This assessment includes an analysis of each member’s qualifications as a director and each member’s independence, as well as consideration of age, experience and other factors in the context of the needs of our Board.

Director Criteria

Pursuant to our corporate governance guidelines, a majority of our directors must meet the standards for independence as required by Nasdaq, and no director may serve on more than three other public company boards of directors unless approved in advance by our Board. Further, applicable Nasdaq rules provide that at least one member of our Board must meet the criteria for an “audit committee financial expert” as defined by SEC rules, and the members of certain of our Board committees must satisfy enhanced independence and financial expertise standards under applicable Nasdaq and SEC rules. We also believe all directors should possess the following attributes:

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Other than the foregoing, there are no stated minimum criteria for director nominees, and our nominating and corporate governance committee may consider these factors and any such other factors as it deems appropriate. Our nominating and corporate governance committee does, however, review the activities and associations of each potential director candidate to ensure there is no legal impediment, conflict of interest or other consideration that might hinder or prevent service on our Board.

Although we do not have a formal policy with respect to Board diversity, our nominating and corporate governance committee strives to assemble a board of directors that brings to our Company a variety of perspectives, skills and expertise. To achieve this, our nominating and corporate governance committee considers individuals diversity in the broadest sense, including persons diverse in geography, gender, ethnicity, age, and experience, including business, professional, governmental, community involvement and natural gas and energy industry experience, in recommending director nominees to our Board.

Our nominating and corporate governance committee assesses these and other factors as it deems appropriate in connection with its annual review of each director and our Board as a whole and takes these factors into account when determining whether to nominate existing directors for re-election in connection with this annual review. Our nominating and corporate governance committee also takes these factors into account when considering any director nominee outside of its annual review process, such as when a vacancy exists on our Board or when a stockholder suggests a new director candidate that the committee or our Board decides to consider for appointment.

Board Refreshment

We aim to regularly bring new directors to our Board at a responsible pace to ensure our Board benefits from fresh ideas and perspectives, while balancing the importance of directors who have experience with our Company.

Board refreshment is a key matter considered during our annual Board and committee self-evaluations. The average tenure of our nominated Board members is eleven (11) years.

Key Qualifications, Skills and Attributes

Our nominating and corporate governance committee regularly reviews the appropriate skills and characteristics required of Board members in the context of the composition of our Board, our operating requirements, and the long-term interests of stockholders. When conducting its review of the key qualifications, skills and attributes desired of Board members, our nominating and corporate governance committee particularly considers:

Senior Leadership Experience

Board members who have served in senior leadership positions, such as a chief executive officer, chairman, senior executive, or leader of significant operations, are important to us because they have the experience and perspective to analyze, shape and oversee the execution of important strategic, operational and policy issues. These Board members’ insights and guidance, and their ability to assess and respond to situations encountered by our Board, may be enhanced by leadership experience at complex businesses or organizations.

RNG and Conventional Natural Gas and Industry Experience

Because we are seeking to drive adoption of RNG and conventional natural gas as a vehicle fuel by fleet vehicle operators, primarily in the trucking, airport, refuse, public transit, industrial and institutional energy user and government fleet markets, relevant education or experience in our industry is key for understanding our markets, strategy, risk management and operations.

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Government, Legal, Public Policy and Regulatory Experience

Board members who have served in government positions provide experience and insights that help us work constructively with governments and address significant public policy issues. Board members with a background in law can assist our Board and legal team in fulfilling its oversight responsibilities regarding our legal and regulatory compliance and our engagement with regulatory authorities.

Financial Expertise

Knowledge of financial markets, financing and funding operations and accounting and financial disclosure and reporting processes is important to have well-represented on our Board. This experience helps our Board members in understanding and overseeing our capital structure, financing and investing activities, as well as our financial reporting and internal controls.

Public and Private Company Board Experience

Board members with public and private company board experience understand the dynamics and operations of a corporate board. These matters include the relationship of a company board with senior management personnel, the legal and regulatory landscape in which companies must operate, the importance of particular agenda and oversight issues, and how to oversee an ever-changing mix of strategic, operational and compliance-related matters.

From time to time, our nominating and corporate governance committee will also consider such other qualifications, skills and attributes as it deems appropriate given the needs of our Board and our Company to maintain a balance of knowledge, experience, background and capability.

Director Nominee Evaluations

At least annually, our nominating and corporate governance committee leads an evaluation of each of our directors and our Board as a whole and each of its committees. In evaluating whether a current director should continue to serve on our Board, our nominating and corporate governance committee considers a number of factors, including those described above and each director’s qualifications, skills and attributes in the areas identified by our nominating and governance committee as particularly important to our Board. In concluding that each of the director nominees should continue to serve as directors of our Company, our nominating and corporate governance committee considered their knowledge, experience and expertise in these areas as indicated in the table below, which they gained from their professional backgrounds described under “Director Nominees” above.

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Vote Required for Approval of the Election of Directors

Directors are elected by a plurality of votes cast in the election of directors at the Annual Meeting. The six nominees who receive the highest number of affirmative votes will be elected as directors. Shares voted “Withhold” and broker non-votes are not counted as votes cast and will have no effect on the outcome of the election of directors.

OUR BOARD RECOMMENDS A VOTE “FOR ALL” THE DIRECTOR NOMINEES

NAMED IN THIS PROPOSAL 1

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PROPOSAL 2

RATIFICATION OF APPOINTMENT OF INDEPENDENT REGISTERED

PUBLIC ACCOUNTING FIRM

General

We are asking our stockholders to ratify the appointment of KPMG LLP as our independent registered public accounting firm for our fiscal year ending December 31, 2026. KPMG LLP has audited our financial statements annually since 2001. Representatives of KPMG LLP are expected to be present at the Annual Meeting. They will have the opportunity to make a statement, if they desire to do so, and respond to appropriate questions from stockholders.

Although our amended and restated bylaws do not require that our stockholders approve the appointment of our independent registered public accounting firm, we are submitting the appointment of KPMG LLP to our stockholders for ratification as a matter of good corporate practice. If our stockholders vote against the ratification of the appointment of KPMG LLP, our audit committee may consider whether to retain the firm. Even if our stockholders ratify the appointment of KPMG LLP, our audit committee may choose to appoint a different independent registered public accounting firm at any time during the year if the committee determines that such a change would, in its judgment, be in the best interests of our Company and our stockholders.

Independent Registered Public Accounting Firm Fees and Services

The following table shows the aggregate fees billed to us for services rendered by KPMG LLP during the periods presented:

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Pre-Approval Policies and Procedures

Pursuant to our audit committee charter, all audit and permitted non-audit and tax services, as well as the fees and terms of such services, that are provided by our independent registered public accounting firm are pre-approved by our audit committee. Our audit committee may also delegate authority to grant pre-approvals to one or more audit committee members, provided that the pre-approvals are reported to the full audit committee at its regularly scheduled meetings. In considering such services for approval, our audit committee considers, among other things, whether the provision of the services is compatible with maintaining the independence of our independent registered public accounting firm.

All services provided by KPMG LLP in 2024 and 2025 were pre-approved by our audit committee in accordance with the foregoing pre-approval policy.

Vote Required for Approval of the Ratification of the Appointment of Independent Registered Public Accounting Firm

The affirmative vote of a majority of the votes cast at the Annual Meeting is required to approve this Proposal 2. Abstentions are not treated as votes cast and will not be counted in determining the outcome of this Proposal 2.

OUR BOARD RECOMMENDS A VOTE “FOR” THE RATIFICATION OF THE APPOINTMENT OF KPMG LLP AS OUR INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

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AUDIT COMMITTEE REPORT

The audit committee is responsible for overseeing our accounting, auditing and financial reporting practices on behalf of the Board. Management is responsible for the preparation and presentation of our consolidated financial statements, including establishing accounting and financial reporting principles and establishing and maintaining systems of internal control over financial reporting. Our independent registered public accounting firm is responsible for expressing an opinion on our consolidated financial statements and an opinion on our internal control over financial reporting.

In performing its responsibilities, the audit committee has reviewed and discussed, with management and KPMG LLP, our independent registered public accounting firm, the audited consolidated financial statements included in the Annual Report. The audit committee has also discussed with KPMG LLP the matters required to be discussed by the applicable requirements of the Public Company Accounting Oversight Board (the “PCAOB”) and the SEC.

Additionally, the audit committee has received the written disclosures and the letter from KPMG LLP required by applicable requirements of the PCAOB regarding KPMG LLP’s communications with the audit committee concerning independence and has discussed with KPMG LLP its independence.

Based on the reviews and discussions referred to above, the audit committee recommended to the Board that the audited consolidated financial statements of Clean Energy Fuels Corp. be included in our Annual Report for filing with the SEC.

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This audit committee report shall not be deemed to be “soliciting material,” or to be “filed” with the SEC or subject to Regulation 14A or 14C under the Exchange Act, other than as provided by applicable SEC rules, or to the liabilities of Section 18 of the Exchange Act, except to the extent that we specifically request that the information be treated as soliciting material or specifically incorporate it by reference into a document filed under the Securities Act or the Exchange Act. This audit committee report will not be deemed to be incorporated by reference into any filing under the Securities Act or the Exchange Act, except to the extent that we specifically incorporate it by reference.

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PROPOSAL 3

ADVISORY, NON-BINDING VOTE TO APPROVE EXECUTIVE COMPENSATION

The Dodd-Frank Wall Street Reform and Consumer Protection Act of 2010 (“Dodd-Frank Act”) enables our stockholders to vote to approve, on an advisory, non-binding basis, the compensation of our named executive officers as disclosed in this Proxy Statement in accordance with the SEC’s compensation disclosure rules.

As described in detail under “Compensation Discussion and Analysis” below, our executive compensation program is designed to attract, retain and motivate talented and dedicated executive officers; to reward individual performance and achievement of key corporate objectives without promoting excessive or unnecessary risk-taking; to align the interests of our executives with those of our stockholders; and to provide compensation that we believe is fair in light of an executive’s experience, responsibilities, performance and tenure with our Company and in relation to the compensation provided to other executives of our Company and certain peer companies. Under this program, determinations regarding each named executive officer’s compensation are based on, among other factors, the individual’s performance and contribution to our strategic plan and other business objectives; our Company’s overall performance, in light of business and industry conditions; general industry benchmarks and trends, including the compensation practices of certain peer companies; the level of the individual’s responsibility; the seniority of the individual; the individual’s long-term commitment to our Company; the available pool of individuals with similar skills; principles of pay equity and relative pay; the role of each compensation component in achieving the objectives of our executive compensation program; and our compensation committee’s business judgment and experience. Please read the “Compensation Discussion and Analysis” in this Proxy Statement for additional details about our executive compensation program.

We are asking our stockholders to indicate their support for our named executive officer compensation as described in this Proxy Statement. We believe the compensation of our named executive officers is appropriate and serves to both incentivize and retain our highly skilled executive leadership team. Attracting, retaining and motivating key executives is crucial to our success. This say-on-pay proposal gives our stockholders the opportunity to indicate whether they approve of our named executive officers’ compensation. This vote is not intended to address any specific component of compensation, but rather relates to the overall compensation of our named executive officers and our executive compensation philosophy, policies and practices described in this Proxy Statement in accordance with the SEC’s compensation disclosure rules. Accordingly, we ask that our stockholders vote “FOR” the following resolution at the Annual Meeting:

“RESOLVED, that the Company’s stockholders approve, on an advisory, non-binding basis, the compensation of the Company’s named executive officers, as disclosed in the Company’s Proxy Statement for its 2026 Annual Meeting of Stockholders pursuant to the compensation disclosure rules of the Securities and Exchange Commission, including the Compensation Discussion and Analysis, the Summary Compensation Table and the other related tables and disclosure included therein.”

This say-on-pay proposal is being provided as required by Section 14A of the Exchange Act and is advisory and therefore not binding on our Company, our compensation committee or our Board in any way. Our Board and our compensation committee value the opinions of our stockholders, and to the extent there is any significant vote against the named executive officer compensation as disclosed in this Proxy Statement, we will consider our stockholders’ concerns and our compensation committee will evaluate whether any actions are necessary to address these concerns.

At our 2023 annual meeting of stockholders, a majority of stockholders voted to have a say-on-pay vote each year. As a result, we will conduct an advisory vote on executive compensation annually at least until the next stockholder advisory vote on the frequency of such votes. It is expected that the next such say-on-pay vote will occur at the 2027 annual meeting of stockholders.

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Vote Required for Approval of the Compensation of Our Named Executive Officers

The affirmative vote of a majority of the votes cast at the Annual Meeting is required to approve this Proposal 3. Abstentions and broker non-votes are not treated as votes cast and will not be counted in determining the outcome of this Proposal 3.

OUR BOARD RECOMMENDS A VOTE “FOR” THE APPROVAL OF THE COMPENSATION OF

OUR NAMED EXECUTIVE OFFICERS, AS DISCLOSED IN THIS PROXY STATEMENT

PURSUANT TO THE COMPENSATION DISCLOSURE RULES OF THE SEC

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CORPORATE GOVERNANCE

Board and Committee Composition

The following sets forth certain key features of the composition of our Board and its standing committees.

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Board Committees

We have established the following standing committees: an audit committee, compensation committee, and nominating and corporate governance committee. Our Board also creates committees from time to time to oversee financing transactions or other significant corporate matters. Our Board and standing committees meet as frequently as necessary in order to properly discharge their responsibilities. Each of our Board committees has the responsibilities described below. Copies of the current charters of our audit committee, compensation committee, and nominating and corporate governance committee, as adopted by our Board, are accessible on our website at
https://investors.cleanenergyfuels.com/corporate-governance/governance-documents.

Audit Committee

We believe the functioning of our audit committee complies with all applicable requirements of the Sarbanes-Oxley Act of 2002 and with all applicable Nasdaq and SEC rules. The functions of this committee include:

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Compensation Committee

We believe the functioning of our compensation committee complies with all applicable Nasdaq and SEC rules. The functions of this committee include:

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Nominating and Corporate Governance Committee

We believe the functioning of our nominating and corporate governance committee complies with all applicable Nasdaq and SEC rules. The functions of this committee include:

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Board Leadership Structure

Our Board has determined that our current structure of separating the roles of Chairman of the Board and Chief Executive Officer is in the best interests of our Company and our stockholders. Mr. Scully has served as Chairman of the Board since January 2018, and Mr. Corbus has been the Chief Executive Officer of our Company since April 22, 2026. Prior to the Chief Executive Officer Transition (as described further below), Mr. Littlefair served as the Chief Executive Officer since June 2001. As Chairman of the Board, Mr. Scully focuses on organizing Board activities to enable our Board to effectively provide guidance to and oversight (including risk oversight) and accountability of management. The Chairman of the Board, among other things, creates and maintains an effective working relationship with the Chief Executive Officer and other members of management and with the other members of our Board, provides the Chief Executive Officer ongoing direction regarding Board needs, interests and opinions, and ensures our Board agenda is appropriately directed toward matters significant to our Company. Separating the roles of Chairman of the Board and Chief Executive Officer allows Mr. Corbus, as Chief Executive Officer, to focus on managing the day-to-day direction and implementing the long-term strategic goals of our Company. The functions of our Board are carried out by the full Board and, when delegated, by our Board’s committees. Each director is a full and equal participant in the major strategic and policy decisions of our Company.

Board Role in Risk Oversight

Risk is inherent in every business. We face a number of risks, including business, operational, strategic, competitive, financial, political, legislative, environmental, safety and regulatory risks, as well as risks related to compensation, cybersecurity threats or incidents, artificial intelligence, capital expenditures, derivative transactions, commodity-based exposures, acquisitions or other strategic transactions and financing and other liquidity matters. In general, our management is responsible for the day-to-day management of the risks we face, while our Board, as a whole and through its committees, is responsible for the oversight of risk management.

In its risk oversight role, our Board and each of its committees regularly review and discuss, internally and with management, the material short-, intermediate-, and long-term risks confronting our business, based on reports prepared and delivered by management and outside advisors that address these risks and other information deemed relevant. Our Board also monitors our risk management and corporate governance policies, including the day-to-day risk management processes designed and implemented by management, and generally evaluates how management operates our Company with respect to risk exposures. These risks and risk management policies are also reviewed and analyzed in depth by our Board at an annual strategic planning session with members of senior management. Due to the dynamic nature of risk and the business environment generally, management regularly updates our Board on key enterprise risks. Board and committee agendas and meeting materials are updated throughout the year so that emerging enterprise risks may be reviewed and discussed at relevant times. We believe this process facilitates our Board’s ability to fulfill its oversight responsibilities of our Company’s risks in a timely and effective manner. Our Board considers the risks and vulnerabilities we face when granting authority to management and approving business strategies and particular transactions.

Our Board performs its risk oversight function in part through its committees, which are comprised solely of independent directors. Each Board committee’s risk oversight role is as follows:

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Code of Ethics

We have adopted a written code of ethics applicable to our directors, officers and other employees, including our principal executive, financial and accounting officers and controller or persons performing similar functions. This code of ethics establishes policies to promote honest and ethical conduct and is designed to comply with applicable Nasdaq and SEC rules. Our nominating and corporate governance committee reviews our code of ethics periodically and may propose or adopt additions or amendments that it determines are required or appropriate.

Our code of ethics is accessible on our website at https://investors.cleanenergyfuels.com/corporate-governance/governance-documents. We expect that any amendments to or waivers from certain provisions of our code of ethics applicable to any principal executive, financial or accounting officer or controller or persons performing similar functions will be disclosed on our website to the extent required by applicable Nasdaq or SEC rules.

Insider Trading Policy

We have adopted an insider trading policy (our “Insider Trading Policy”) that governs, among other things, purchases, sales, and/or other dispositions involving our securities by our directors, officers and employees. We believe our insider trading policies and procedures are reasonably designed to promote compliance with insider trading laws, rules, regulations, and applicable Nasdaq listing standards. Our Insider Trading Policy is filed as Exhibit 19.1 to our Annual Report on Form 10-K for the fiscal year ended December 31, 2025. Because our insider trading policies and procedures are designed to address transactions in our Company’s securities by our directors, officers, and employees, we do not have formal insider trading policies or procedures that govern our purchase of our Company’s securities.

Corporate Governance Guidelines

We have adopted written corporate governance guidelines that set forth standards for director qualifications and responsibilities, Board committees, Board leadership structure, director compensation, director orientation and continuing education, management succession, Board self-evaluations, Board oversight of our Company’s strategic planning, and director and officer stock ownership, among other things. Our nominating and corporate governance committee reviews our corporate governance guidelines periodically and may from time to time propose or adopt additions or amendments it determines are required or appropriate. Our corporate governance guidelines are accessible on our website at http://investors.cleanenergyfuels.com/corporate-governance/governance-documents.

Board Evaluations

At least annually, our Board and each of our standing committees conduct an evaluation of our Board and each of our directors. As part of this evaluation, our Board considers the areas in which our Board believes it could improve or be more effective. Each of our committees also conducts an evaluation of itself at least annually.

Management Succession

Our Board works with our nominating and corporate governance committee to evaluate potential successors to our Chief Executive Officer and to ensure that a Chief Executive Officer succession plan is in place. Our Chief Executive Officer also makes available his recommendations and evaluations of potential successors, as well as reviews any development plans recommended for such individuals.

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Stockholder Communications with our Board

We have adopted a formal process by which stockholders and interested parties may communicate with our Board, which is accessible on our website at https://investors.cleanenergyfuels.com/corporate-governance/contact-the-board. This centralized process assists our Board in reviewing and responding to communications from stockholders and other interested parties in an appropriate manner. Communications to our Board must be in writing and mailed to our Corporate Secretary at the address of our principal executive offices. The communication can be addressed to one or more individual directors or to our Board as a group, and the name of any specific intended recipient(s) should be noted in the communication. Communications submitted by postal mail may be anonymous. Our Corporate Secretary typically reviews all such communications and will forward them to our Board or any identified individual director(s), unless any such communication is deemed to be, in our Corporate Secretary’s discretion, unrelated to the duties and responsibilities of our Board or unduly hostile, threatening, illegal or similarly unsuitable for Board consideration.

Director Nomination Process

Our Board, as a whole and through our nominating and corporate governance committee, is responsible for identifying, evaluating and recommending nominees to serve as directors of our Company.

Identifying and Evaluating Director Nominees

Our nominating and corporate governance committee is responsible for identifying individuals qualified to become members of our Board and recommending these candidates to our Board for nomination or appointment. Our nominating and corporate governance committee may utilize a variety of methods to identify potential director candidates. For example, candidates may come to the attention of our nominating and corporate governance committee through current members of our Board, executive officers, professional search firms, stockholders or others. These candidates may be evaluated and considered by our nominating and corporate governance committee at any point during the year, including in connection with each annual meeting of our stockholders. For each such annual meeting, our nominating and corporate governance committee recommends to our Board certain director nominees to stand for election at the annual meeting based on the committee’s evaluation of all potential director candidates, including incumbent directors. Our Board then selects director nominees based on its determination, relying on the recommendation of and other information provided by our nominating and corporate governance committee as it deems appropriate, of the suitability of each potential director candidate to serve as a director of our Company.

Stockholder Recommendations of Director Candidates

In accordance with its charter, our nominating and corporate governance committee is responsible for considering and evaluating properly submitted stockholder recommendations of candidates for Board membership. Any such recommendation of director candidates for nomination by our Board in connection with our next annual meeting of stockholders should be made in writing and delivered or mailed to our Corporate Secretary at the address of our principal executive offices, and should include the name, age, address and a current resume of the proposed director candidate, the number of shares of our common stock that are beneficially owned by the person the stockholder is nominating, a statement describing the candidate’s qualifications and consent to serve on our Board if selected as a director nominee, and contact information for personal and professional references. The submission should also include the name and address of the stockholder who is submitting the proposed director candidate, the number of shares of our common stock that are owned of record or beneficially by the submitting stockholder and a description of all arrangements or understandings between the submitting stockholder and the proposed director candidate. We may also request that any proposed director candidate and any stockholder proposing a director candidate furnish us with such other information as may reasonably be required for our nominating and corporate governance committee to determine the eligibility of such proposed director candidate to serve as a director of our Company.

All properly submitted stockholder recommendations will be aggregated together and with any other director candidates proposed by other sources, for consideration and evaluation by our nominating and corporate governance committee and will receive the same consideration by our nominating and corporate governance committee as is received by any other director candidate. In evaluating all director candidates, our nominating and corporate governance committee

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will consider, among other things, the director qualifications set forth in our corporate governance guidelines, as described in “Proposal 1: Election of Directors” above. Any stockholder-recommended director candidate that is selected by our nominating and corporate governance committee would be recommended by the committee as a director nominee to our Board, which would then consider and evaluate the candidate in the same manner and based on the same criteria and qualifications as other prospective director candidates. If approved by our Board, the stockholder-recommended candidate would be appointed as a director to a vacant seat on our Board or included in our Board’s slate of director nominees to stand for election at our next annual meeting of stockholders.

Stockholder Nominations of Directors

A stockholder who wishes to nominate a director must comply with all applicable requirements set forth in our amended and restated bylaws. In accordance with these requirements, any stockholder nomination of a director must be made in writing and delivered to or mailed and received by our Corporate Secretary at the address of our principal executive offices within a specified time period before the annual meeting of stockholders at which the director nominee is to be up for election. See “Stockholder Proposals for 2027 Annual Meeting” below for information about these time periods in connection with our 2027 annual meeting of stockholders. Any such recommendation must include the following information:

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Sustainability

Our vision is to deliver renewable transportation fuel for a cleaner, safer, more equitable tomorrow. We launched our strategy and goals to drive progress across three pillars: fueling the transition to renewable energy in transportation, building the workforce for the future of renewable energy, and advancing smart policies that drive the transformation to renewable fuels.

In 2025, we continued to focus on building trusted partnerships with our stakeholders to help achieve progress towards our goals, as well as on improving our operations to align with our sustainability goals. We recognize that our environmental impact includes more than our products and that we must foster a culture of sustainability in everything we do. Each of the three pillars of our sustainability strategy incorporates parts of our own business operations, to ensure that our advocacy and external progress in sustainability is aligned with our internal operations. In November 2025, we published a sustainability report that is posted on our website at https://www.cleanenergyfuels.com/sustainability, which highlights the efforts of different teams across the organization and provides information on our performance on material sustainability issues.

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INFORMATION ABOUT EXECUTIVE OFFICERS

The names of our executive officers, their ages as of the date of this Proxy Statement, their current positions and offices with our Company and, for executive officers who are not also members of our Board, other information about their backgrounds are shown below. As disclosed in our Current Report on Form 8-K filed on April 23, 2026, on April 22, 2026, in connection with our Company’s Chief Executive Officer Transition, our Board appointed Mr. Corbus as the Company’s President and Chief Executive Officer to succeed Mr. Littlefair. The biographical information for Mr. Corbus is described above, under the section “Election of Directors.” We have entered into employment agreements with each of our executive officers, which are described under “Compensation Discussion and Analysis — Employment Agreements” below, that establish, among other things, each executive officer’s term of office. There are no arrangements or understandings between any of our executive officers and any other person pursuant to which such individual was or is selected as an officer of our Company.

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Robert M. Vreeland has served as our Chief Financial Officer since October 2014. From 2012 to 2014, Mr. Vreeland served as our Vice President, Finance and Accounting. Prior to joining our Company, Mr. Vreeland was managing member at RV CPA Services, PLLC, a provider of accounting services. From 1997 to 2009, Mr. Vreeland held various finance and accounting positions at Hypercom, an electronic payment and digital transactions service provider, including Interim Chief Financial Officer, Senior Vice President and Corporate Controller, Senior Vice President, Operations, and Vice President of Financial Planning and Analysis. Prior to joining Hypercom, Mr. Vreeland spent 12 years at Coopers & Lybrand, an accounting firm that later merged to become PricewaterhouseCoopers. Mr. Vreeland earned a B.S. from Northern Arizona University and is a certified public accountant.

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COMPENSATION DISCUSSION AND ANALYSIS

Introduction

This compensation discussion and analysis describes the material features of the 2025 compensation program for our executive officers in 2025, who were:

Andrew J. Littlefair, Former President and Chief Executive Officer

Robert M. Vreeland, Chief Financial Officer

Barclay F. Corbus, Current President and Chief Executive Officer and former Senior Vice President, Strategic Development and Head of Renewable Fuels

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These are the only individuals who served as executive officers at the end of 2025 or at any time during the 2025 calendar year. Messrs. Littlefair, Vreeland, and Corbus are collectively referred to in this proxy statement as our “named executive officers”. This analysis also discusses our compensation philosophy and objectives, the methodologies used for establishing our compensation programs for the named executive officers, and the policies and practices for administering such programs.

On April 23, 2026, the Company announced Mr. Corbus’s appointment as the Company’s new President and Chief Executive Officer, succeeding Mr. Littlefair effective as of April 22, 2026.  We refer to this succession as the “Chief Executive Officer Transition” in this Proxy Statement.  Because Mr. Corbus became our President and Chief Executive Officer during 2026 and this Compensation Discussion and Analysis and the executive compensation tables and disclosures that follow are required to discuss our named executive officers’ compensation during 2025, references to our Chief Executive Officer or CEO in the executive compensation sections of this Proxy Statement generally refer to Mr. Littlefair because he was our Chief Executive Officer for the entirety of 2025 prior to the Chief Executive Officer Transition.  

Executive Summary: Key 2025 Compensation Actions and Outcomes

Performance Highlights: Significant shifts in the US macro environment for alternative energy in 2025 created high levels of volatility and presented headwinds for our Company’s business. Despite these challenges, we are proud to have delivered growth in several key financial and operating metrics during the year. Beyond growth, we took actions that improved our financial health and built a foundation for profitable growth going forward. In addition, we continued to make progress on strategic objectives that position us well for the future. Key 2025 highlights include:

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Stockholder Engagement: We actively engaged with seven stockholders in 2024, representing 43% of total ownership, and used stockholder feedback to design our 2025 compensation program. Key input received and actions taken by our Company include:

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Compensation Program Objectives and Philosophy

Our compensation committee oversees the design and administration of our executive compensation program. The primary objectives of our executive officer compensation program are to attract, retain and motivate talented and dedicated executive officers; to reward individual performance and achievement of key corporate objectives, including the objectives set forth in our annual strategic plan, without promoting excessive or unnecessary risk-taking; to align the interests of our executive officers with those of our stockholders; and to provide compensation that we believe is fair in light of an executive officer’s experience, responsibilities, performance and tenure with our Company and in relation to the compensation provided to other executives of our Company and comparable executives at our peer companies. While we do not use a formal benchmarking approach, we generally use market median total pay positioning as a reference point for setting the target compensation of our executive officers, although that may vary somewhat by individual based on factors such as experience and performance.

To achieve these objectives, we maintain an executive compensation program that includes the following components: base salary, cash incentives, equity incentives, change in control and post-termination severance compensation, and other benefits. The compensation program also places a strong emphasis on pay-for-performance, as a significant portion of

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executive compensation must be earned through the annual cash bonus opportunity, and our equity incentives align our executive officers with stockholders and encourage value creation in order to realize upside through share price appreciation and business objective achievement. Our compensation committee developed our executive compensation program by drawing on its experience and judgment in establishing programs it believes are appropriately rewarding and responsible for a growth company in a developing industry. Our compensation committee reviews and evaluates our executive compensation program, including its objectives and the forms of compensation used to achieve these objectives, on at least an annual basis, and adjusts the program as it deems appropriate and considers factors relevant in establishing appropriate levels and mix of compensation for our executive officers.

In 2024, our compensation committee engaged directly with stockholders to garner specific feedback on the program and the overall compensation philosophy to help ensure program alignment with stockholder preferences. Our Company received valuable feedback from stockholders on potential enhancements to align pay more directly with performance, which has led to certain changes to our 2025 compensation programs as discussed herein.

Process for Determining Executive Compensation

Compensation Committee’s Role

Our compensation committee’s general practice is to establish the annual compensation mix and levels for each of our executive officers at the beginning of each fiscal year, typically in our first quarter in connection with annual performance reviews. Performing this process after the end of the prior year allows our compensation committee to incorporate information on our Company’s and each individual’s performance during the prior year and to assess each executive officer’s overall contributions to our Company. Additional factors considered when establishing pay levels and designs include market practices and stockholder input. Our compensation committee then compiles this information to establish annual target compensation and performance targets for incentive plans.

Management’s Role

In determining the mix and level of compensation components for our named executive officers, Mr. Littlefair, our President and Chief Executive Officer during 2025, typically made recommendations to our compensation committee regarding appropriate pay. After reviewing Mr. Littlefair’s recommendations, our compensation committee made the final determination regarding compensation mix and levels for each of our named executive officers. Although Mr. Littlefair submitted recommendations to our compensation committee regarding his own proposed compensation, which the committee took under advisement, Mr. Littlefair did not participate in our compensation committee’s deliberations regarding his own compensation. Additionally, the financial performance criteria of our annual incentive plan are prepared by our Chief Financial Officer based on our annual budget, and the strategic initiatives are developed by our Chief Executive Officer, with the plan design and targets ultimately being approved by our compensation committee.

Mr. Littlefair’s recommendations and our compensation committee’s decisions regarding the mix and level of compensation components for each of our named executive officers are based on a number of factors, including, among others, the individual’s performance and contribution to our strategic plan and other business objectives; our Company’s overall performance in light of business and industry conditions; general industry trends and market reference points; the level of the individual’s responsibility; the experience and seniority of the individual; the individual’s long-term commitment to our Company; the available pool of individuals with similar skills; retention risk for the individual; and internal pay equity relative to responsibilities and performance.

Compensation Consultant

Our compensation committee has the authority to engage the services of compensation consultants or other experts or advisors as it deems appropriate in fulfilling its responsibilities and has retained the services of Semler Brossy. Our compensation committee has the sole authority to approve the terms of this engagement, and Semler Brossy reports to our compensation committee only under this engagement and does not provide any additional services to us other than its work for our compensation committee. In conjunction with engaging Semler Brossy, our compensation committee determined that Semler Brossy was independent and that its work would not raise any conflicts of interest after taking into

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consideration the factors set forth in applicable Nasdaq and SEC rules. In 2025, Semler Brossy assisted as part of the engagement and supported our compensation committee in: reviewing our Board of Director pay levels and compensation plan; reviewing our peer group for 2026 compensation actions; analyzing our equity pool usage; providing executive pay and incentive design benchmarking to help inform 2025 compensation decisions for the executive team; providing input on general market and governance trends; supporting our stockholder engagement efforts; providing information on Say-on-Pay trends; and supporting on various other ad hoc and governance-related items.

Peer Group

Selecting a group of peer companies with comparable business profiles to Clean Energy is challenging because there are few publicly traded companies in our line of business that are of comparable size. In selecting peer companies for compensation purposes, our compensation committee generally sought to identify companies that operate in similar industries with generally comparable business scales, and that, in our compensation committee’s view, compete with us for talent.

2024 Peer Group Approval to Inform 2025 Compensation Decisions

In September 2024, considering the compensation consultant’s recommendations, our compensation committee approved the 16 companies listed below as our peer companies that were used for 2025 compensation purposes, which we refer to collectively as the “2025 Peer Group.” These companies mainly had revenue of approximately 1/3x to 3x that of Clean Energy and a significant portion of their business related to alternative/renewable energy production or supporting industries. In cases where the selected peer deviated from that profile, the company was selected due to its industry relevance.

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2025 Updated Peer Group Approval to Inform 2026 Compensation Decisions

In September 2025, the compensation committee and its compensation consultant undertook a thorough review of the peer group, both as part of the annual review process and in consideration feedback gathered from our stockholders, in order to ensure a sound process and rationale in determining executive pay levels. The goal was to construct a peer group that maintained a high level of comparability in the alternative/clean energy space while improving the degree of alignment with Clean Energy’s financial profile. The compensation consultant recommended the removal of four companies that had revenue or market capitalization well above ours, including Darling Ingredients, Northern Oil and Gas, Enphase Energy, and AeroVironment. Three companies with more comparable financial and business profiles were proposed for inclusion: REX American Resources, Centrus Energy, and American Superconductor. In considering the compensation consultant’s recommendations, the compensation committee approved the 15 companies listed below as our peer companies that were used for 2026 compensation purposes, which we refer to collectively as the “2026 Peer Group.”  

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Role of Peer Group Comparison in Setting Compensation Levels

Our compensation committee believes that comparing pay levels and practices to comparable peer companies is a valuable input in establishing our executive officer pay strategy, though it is not the only tool used for setting compensation due to aspects of our business, objectives, and the way we have structured executive roles that may be unique to our Company. Our compensation committee also considers internal equity, individual performance, tenure, recent pay levels, and input from our President and Chief Executive Officer and from the compensation consultant, among other factors, in determining final pay levels. The executive pay structure and levels included in this proxy statement were determined based on all of the above factors, in conjunction with considering the peer group as set forth above.

Review of Stockholder Feedback and Say-on-Pay Votes

As noted in the Executive Summary above and elsewhere, we actively solicit feedback from stockholders and consider this input in determining our executive pay strategies. In addition, we hold an annual Say-on-Pay vote to garner direct feedback from stockholders on our executive compensation programs. We received support for our 2024 executive compensation program from approximately 87% of the voting stockholders at our 2025 annual meeting of stockholders, which indicated strong alignment with stockholders over executive compensation.

Components of Compensation

Our named executive officers’ compensation consists of the following components:

Our compensation committee strives to provide a balanced and market-aligned pay mix that reflects several key compensation philosophy principles. Overall target pay levels and mix should generally align with market practices and be competitive vs. comparable companies and roles. Additional considerations are specific to the reward element. Base salaries should reflect individual experience and performance, while also managing fixed costs in a prudent manner. The performance-based annual cash incentives should reinforce our business priorities and encourage performance at or ahead of our budgeted objectives. Equity should represent a significant portion of total compensation for senior leaders to provide alignment with stockholders while also creating a focus on specific long-term performance goals.

Base Salaries for 2025

We provide base salaries to recognize the experience, skills, knowledge, and responsibilities of our named executive officers; reward individual performance and contribution to our overall business goals; and retain our executives. Our compensation committee reviews base salaries annually, considers our market benchmarking assessment, and relies on its judgment and discretion in determining the amount of each named executive officer’s base salary. Proposed base salaries were prepared by Mr. Littlefair and recommended to our compensation committee for its consideration and approval.

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Base salaries for our named executive officers in effect as of March 2024 and March 2025 are as follows:

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Mr. Littlefair’s 2025 base salary remained the same as his 2024 base salary, based on the compensation committee’s determination that he was adequately positioned relative to the market and to signal an overall focus on cost management. The increases to Mr. Vreeland’s and Mr. Corbus’s base salaries for 2025 are reflective of merit-based increases intended to promote retention. The modest revisions to base salaries for 2025 reflect a conservative approach with an emphasis on prudent financial management.

Cash Incentives for 2025 – Performance-Based Cash Incentive Bonus Plan

Our compensation committee believes cash incentives are important to focus our management on and reward our executives for achieving financial and strategic objectives on an annual basis, as well as to provide competitive pay opportunities to attract and retain strong talent. Our compensation committee determines performance criteria, considers factors and developments it deems relevant, and awards overall cash incentives in the amounts it deems appropriate based on performance. At the beginning of each year our compensation committee approves a performance-based cash incentive plan that reflects both the strategic priorities of the Company as well as its targeted performance objectives. Following the completion of the year, the compensation committee approves payment of incentives after reviewing our performance with respect to the criteria set forth in the plan.

Program Design and Performance Results – 2025 Performance-Based Cash Incentive Bonus Plan

The 2025 performance-based cash incentive bonus plan uses a variety of metrics that reflect our business priorities and that are focused on bottom-line profitability, fueling supply, and company strategy. Weighting by metric represents an approximation of the relative priority and perceived impact on overall current and future stockholder value creation from business results. Current year financial metrics represent 80% of the weighting which we believe properly emphasizes the need to establish and meet challenging near-term objectives. The remaining 20% of our measures are for strategic initiatives. These are items which generally do not directly impact current year financial results but are critical for positioning Clean Energy for future business success.

Payout ranges under the 2025 performance-based cash incentive bonus plan vary by executive: Mr. Littlefair can earn 70% of base salary for achieving base target performance across metrics, 100% for middle target performance, and 150% for maximum target performance, while Messrs. Vreeland and Corbus can earn 50% of base salary for achieving base target performance across metrics, 70% for middle target performance, and 100% for maximum target performance. Each metric is independent, where achievement below the base performance on one metric will not impact earning opportunities for other metrics. Our compensation committee established the target award levels considering market pay factors, the terms of the employment agreements previously entered into with our named executive officers, and the compensation committee’s evaluation of the experience and contributions of each individual.

The compensation committee met in February 2026 to review our Company’s 2025 actual performance versus the financial performance criteria and strategic initiative targets and to determine what payouts, if any, would be made under the 2025 performance-based cash incentive plan. The compensation committee certified achievement outcomes on the various performance measures, with specific considerations as noted below.

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Overall financial performance was above the middle target levels for most metrics, while strategic initiatives were determined to be at the base target level. Total resulting cash funding for Mr. Littlefair was 111% of his salary, while cash payouts for Messrs. Vreeland and Corbus were both 76% of salary. Key performance considerations are highlighted below:

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The base, middle and maximum targets for the performance criteria under the incentive plan approved by our compensation committee for 2025, as well as our actual performance for these criteria, are set forth in the following table.

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In summary, based on our performance for 2025, our compensation committee awarded our named executive officers cash incentives under our performance-based plan as described below, each of which was above the target payment level. Mr. Littlefair received 111%, and Messrs. Vreeland and Corbus received 76%, respectively, of their 2025 salaries in bonus amounts for 2025.

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Equity Incentives for 2025 – RSUs and Introduction of PSUs; Reduction in Target Award Values

We believe long-term performance motivation is achieved through an ownership culture that encourages performance by our named executive officers through the use of stock-based awards. Our equity incentive plans have been established to provide certain of our employees, including our named executive officers, with incentives designed to align these employees’ interests with the interests of our stockholders. In general, our compensation committee develops its equity award determinations based on its judgments as to whether these equity awards are sufficient to further our ownership culture, appropriately align the interests of our named executive officers with those of our stockholders and retain, motivate, and adequately reward our executives on a long-term basis. As described above, the compensation committee also considers the equity award opportunities provided by our peer group companies when making equity award determinations for the named executive officers.

Annual equity incentive grants are generally made in the first quarter of each year. Grant timing is determined and approved by our compensation committee in accordance with general year-end pay decisions. We have also adopted an equity award grant policy that we believe aligns with best corporate governance practices and is intended to prevent grant timing issues in relation to the release of material, non-public information. Our general policy is to grant annual equity awards in Q1 of each year, with the opportunity for off-cycle awards if approved by our compensation committee. Equity awards are generally granted at least one business day or more after the filing of our Annual Report filed on Form 10-K, although we do have the discretion to grant equity awards at other times if determined to be appropriate by our compensation committee. We did not grant any off-cycle awards in 2025 to named executive officers outside of the specified annual awards below.

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Prior to 2025, we have granted our named executive officers stock options, RSUs, or a combination thereof, subject to both time-based and performance-based vesting requirements, and our compensation committee has exercised its judgment on the weighting of stock options relative to RSUs in any given year. For 2025, based on feedback received from our engagement with stockholders and in order to provide greater direct measurement of performance and pay-for-performance alignment, we included performance stock units (“PSUs”) in the equity mix for our named executive officers. For 2025, equity incentives for our named executive officers did not include stock options and instead consisted of a mix of RSUs and PSUs. Our compensation committee designed these awards to align executives with stockholder interests and to encourage our executives to achieve long-term growth goals for our Company. Our compensation committee and our executive team believe in the long-term growth potential of our Company and believe RSUs and PSUs to both be appropriate vehicles in properly incentivizing and rewarding progress in achieving growth.

Target grant values for each of our named executive officers declined materially in 2025 relative to 2024. This reflects share value declines based on the challenging operating environment that was anticipated in 2025 and our committee’s focus on managing share usage and expenses. Grant values for Mr. Littlefair declined by over 20%, Mr. Corbus’ award value declined by 27%, while Mr. Vreeland’s award value was reduced by approximately 57%.

2025 Time-Based Restricted Stock Units (RSUs)

RSUs are full-value awards that represent the contingent right to receive shares of our common stock upon achievement of stated vesting criteria. These awards provide direct alignment with stockholders and encourage value appreciation while also providing retention incentive for our leaders. The time-based RSU awards granted to our named executive officers in 2025 vest over three years at a rate of 34% on the one-year anniversary of the date of grant and 33% on each subsequent anniversary until fully vested, subject to the named executive officer’s continued service with our Company at each vesting date. With the introduction of PSUs in 2025, the RSUs represent 50% of the intended grant value for Mr. Littlefair, and 67% for Messrs. Vreeland and Corbus.

The following table depicts the 2025 RSU awards:

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2025 Performance Stock Units (PSUs)

In our outreach conversations in 2024, stockholders generally communicated a preference for a stronger performance orientation within our incentive programs. We determined it to be in the best interest of stockholders and our Company to incorporate performance-based units (“PSUs”) into the 2025 equity grants for our executives tied to two key growth metrics of our business: (i) stock price and (ii) negative carbon intensity dairy gas sales. We incorporated these PSUs into the 2025 share equity mix with a weighting of 50% PSUs and 50% RSUs for Mr. Littlefair and 33% PSUs and 67% RSUs each for Messrs. Vreeland and Corbus. Additional executives not included within this Proxy Statement also received PSUs as part of their annual equity awards to further motivate our team towards stronger performance. Incorporation of PSUs into our long-term incentive program is intended to align executive interests with our long-term business goals. We will continue to evaluate our incentive programs to ensure alignment with stockholders and business focus over time.

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Price Hurdle PSUs – 50% of PSU Weighting:  Achievement is based on reaching four distinct 30-day trailing average stock price hurdles, over a three-year period. These PSUs are earned based on the achievement of share price multiples ranging from 1.25x to 2.00x the price of the 30-day trailing average stock price of our common stock on the grant date. Any of these PSU awards that are not earned based on performance at the end of the three-year performance period will be forfeited for no consideration. As set forth in the table below, the number of shares to be earned can vary from 0% to 133% of the target award for these shares. These price hurdle PSUs comprise 50% of the total PSUs granted to the named executive officers. These price hurdle PSUs align the interests of management with those of stockholders by incentivizing the achievement of strong share price performance.

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Negative Carbon Intensity (CI) Dairy Gas Sales PSUs – 50% of PSU Weighting:  Achievement is based on the compound annual growth rate of negative CI dairy gas sales year-over-year, measured over a three-year period. Any of these PSU awards that are not earned based on performance at the end of the three-year performance period will be forfeited for no consideration. These negative CI dairy gas sale PSUs comprise 50% of the total PSUs granted to the named executive officers. These PSUs further align the interests of management with stockholders, as they incentivize achievement of a key business objective — an increase in our negative CI dairy gas sales. In addition, negative CI dairy gas sales generate carbon credits, which provide an additional benefit to our business.

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The following table depicts 50% of the total PSU awards which are related to the Price Hurdle PSUs, based on the maximum performance level. Refer to the “Grants of Plan-Based Awards” in this proxy statement for reference to the threshold, target and maximum number of shares that could be issued based on actual performance levels.

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The following table depicts 50% of the total PSU awards which are related to the Negative CI Dairy Gas Sales PSUs, based on the maximum performance level. Refer to the “Grants of Plan-Based Awards” in this proxy statement for reference to the threshold, target and maximum number of shares that could be issued based on actual performance levels.

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Legacy 2021 Multi-Year Performance Stock Options – Current Achievement Levels

In December of 2021, our compensation committee awarded two performance-based stock option programs as additional long-term incentives to our named executive officers. At that time, our Company was at a critical juncture, and our compensation committee determined that it was of primary importance to incentivize the named executive officers to strategically execute on expanding our Company’s RNG business over the long term and to create long-term stockholder value by increasing our Company’s price per share. These awards have the following performance characteristics and current achievement levels:

2026 Equity Incentive Program

For 2026, our compensation committee determined to continue structuring our named executive officer long-term equity awards using a combination of RSUs and PSUs.  We believe this structure remains responsive to stockholder feedback and that the inclusion of long-term performance objectives for the PSU awards continues to emphasize direct measurement of performance and align long-term executive compensation with actual performance results achieved.  For 2026, the compensation committee recalibrated the performance metrics applicable, with two new metrics as follows: (1) an Adjusted EBITDA metric measured over a three-year performance period, which the compensation committee believes is a key long-term stockholder value driver and accomplishes a different compensation objective than the one-year Adjusted EBITDA metric used as one of several metrics under our annual incentive plan; and (2) a metric based on our debt to earnings ratio which was included because the compensation committee wanted to incentivize prudent long-term growth and attention to our long-term capital structure.  Like in 2025, the 2026 PSU performance metrics were developed by the compensation committee with input from Semler Brossy, its independent compensation consultant.

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Other Compensation Policies

Change in Control and Post-Termination Severance Compensation

Our employment agreements with our named executive officers, described under “Employment Agreements” below, provide them certain benefits if their employment is terminated, including a termination following a change in control but excluding a termination by our Company for cause or a voluntary termination by the named executive officer without good reason. Our compensation committee believes these benefits are important tools for retaining the services of our named executive officers and helping to align the interests of our named executive officers with those of our stockholders. The details and amounts of these benefits are described below under “Executive Compensation — Potential Payments Upon Termination or Change in Control.”

All equity awards granted to our named executive officers after November 2014 are subject to double- trigger vesting upon a change in control. Our compensation committee previously determined to modify the standard vesting provisions of our named executive officers’ equity awards from “single-trigger” to “double- trigger” vesting in connection with a change in control because it believes double-trigger vesting more accurately reflects current market practices but still provides appropriate benefits to executives in the event of a termination in connection with a change in control, and is thus in the best interests of our Company and our stockholders. Further, we do not provide any excise tax “gross-up” payments to our executives in connection with a change in control.

Other Benefits

We appreciate the tremendous value and contributions of our employees, and we believe providing a competitive employee benefits program is one of our most important investments. As a result, we offer an employee benefits program with a wide range of plans designed to promote the health and personal welfare of all employees, including our named executive officers. Participation in these plans is generally available to all of our employees on the same basis. Our Company provides minimal perquisites to executives which are noted in the description of “All Other Compensation” disclosed in the Summary Compensation Table of this Proxy Statement.

Employment Agreements

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Executive Stock Ownership Guidelines

We believe it is important to encourage our named executive officers to hold a material amount of our common stock, which links their long-term economic interest directly to those of our stockholders. To achieve this goal, we have established stock ownership guidelines applicable to our named executive officers. These guidelines provide that our Chief Executive Officer is required to own shares of our common stock valued at five times his annual base salary or more, and each of our other named executive officers is required to own shares of our common stock valued at one and one half times their annual base salary or more. Such level of ownership must be attained within five years after the date of an executive officer’s initial appointment as such. Stock options are not counted toward satisfaction of these stock ownership requirements. Executives who attain the applicable stock ownership level by the stated deadline will continue to satisfy the stock ownership requirements if the value of their stock holdings declines after such deadline solely due to a decrease in the trading price of our common stock. Each of our named executive officers had satisfied these stock ownership guidelines as of the Record Date.

Hedging and Pledging of Company Securities

Our policies do not permit any of our executive officers or directors to “hedge” ownership of our securities by engaging in short sales or trading in put options, call options or other derivatives involving our securities. This means that our executive officers and directors may not purchase financial instruments or otherwise engage in transactions that hedge or offset, or are designed to hedge or offset, any decrease in the market value of our equity securities. Further, our policies do not permit an executive officer or director to hold our securities in a margin account or pledge our securities as collateral for a loan unless the executive officer or director demonstrates to our satisfaction financial capacity to substitute other assets for Company securities in the event of a failure to meet a margin call or a default on the loan. As of the date of this Proxy Statement, none of our directors or executive officers has pledged any of the shares of our common stock he or she owns.

Clawback Policy

Our compensation committee has adopted a formal clawback policy regarding recoupment, or a “clawback,” of compensation in certain circumstances. Our clawback policy was amended in 2023 to comply with SEC and NASDAQ clawback policy requirements. The purpose of this clawback policy is to help ensure that executives act in the best interests of the Company and our stockholders.

Tax and Accounting Effects

In designing our compensation programs, our compensation committee considers the financial impact and tax and accounting effects that each element of compensation will or may have on our Company and our executives. One such area our compensation committee considers is the tax deductibility of each component of executive compensation. Prior to December 22, 2017, when the Tax Cuts and Jobs Act of 2017 (“TCJA”) was signed into law, Section 162(m) generally prohibited us from taking a tax deduction in any tax year for compensation paid to certain executive officers that exceeded $1,000,000, unless the compensation was payable only upon the achievement of pre-established, objective performance goals under a plan approved by our stockholders. As a result, we believe certain stock option awards we granted to our named executive officers before the impact of the TCJA have qualified as performance- based compensation under Section 162(m), although there is no guarantee that such equity awards, or any other performance-based compensation paid to our named executive officers, qualify as such. Under the TCJA, the exception for performance-based compensation

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under Section 162(m) has been repealed. Our compensation committee reserves the discretion to make any executive compensation decisions that it considers to be in the best interests of our Company and our stockholders, including to award compensation that may not be deductible.

Timing of Grants of Certain Equity Awards

We grant equity awards on an annual basis and may grant equity awards on a discretionary basis in connection with certain events such as the commencement of employment or promotion. We do not have a formal policy regarding the timing of awards of options in relation to our disclosure of material nonpublic information. However, our compensation committee does not grant option awards in anticipation of the release of material nonpublic information, and we do not time the release of material nonpublic information for the purpose of affecting the value of executive compensation.

Chief Executive Officer Transition

On April 23, 2026, the Company announced Mr. Corbus’s appointment as the Company’s new President and Chief Executive Officer, succeeding Mr. Littlefair effective as of April 22, 2026. As part of the Company’s succession planning, Mr. Littlefair will remain engaged with the Company, as he is willing to continue to serve as a non-employee member of our Board and has agreed to provide consulting services to the Company pursuant to a new consulting agreement.

In connection with Mr. Corbus’s appointment as President and Chief Executive Officer, we entered into an amended and restated employment agreement with Mr. Corbus.   Mr. Corbus’s new employment agreement has an initial term ending April 22, 2029, which will automatically renew for additional one-year terms absent either party giving notice of non-renewal.

Under his employment agreement, Mr. Corbus will receive an annual base salary of $750,000, subject to increase at the discretion of the compensation committee.  Mr. Corbus will be eligible to earn a target annual bonus equal to 100% of his annual base salary, with any actual bonus becoming payable based on the achievement of performance objectives determined by the compensation committee each year.

Although Mr. Corbus’s employment agreement does not entitle Mr. Corbus to receive any specific equity awards, in connection with his appointment, the compensation committee approved an incremental equity grant of time-vesting RSUs with an intended grant date value equal to $413,000, vesting in three substantially equal annual installments on each of the first three anniversaries of his appointment, subject to Mr. Corbus’s continued provision of services.  

The severance benefits under Mr. Corbus’s employment agreement are generally consistent with the severance benefits previously provided to Mr. Littlefair, although Mr. Corbus’s employment agreement does also provide for certain accelerated equity award vesting rights.

In connection with Mr. Littlefair’s resignation, we entered into a consulting agreement with Mr. Littlefair.  The consulting agreement has a three-year term, and engages Mr. Littlefair to provide strategic advisory and government-relations services to the Company under the direction of the Board.  Under the consulting agreement, Mr. Littlefair will be entitled to a base consulting retainer at an annual rate of $750,000 and a grant of RSUs with an intended grant date value equal to $1,000,000, vesting in three substantially equal annual installments on each of the first three anniversaries of the start of the consulting term, subject to Mr. Littlefair’s continued provision of services under the consulting agreement.  Mr. Littlefair will only earn the consulting retainer and vest in his consulting equity award to the extent he continues to provide the consulting services contemplated by his consulting agreement.

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COMPENSATION COMMITTEE REPORT

We, the compensation committee of the Board of Clean Energy Fuels Corp., have reviewed and discussed the Compensation Discussion and Analysis (set forth above) with management of the Company, and based on such review and discussion, have recommended to the Board that the Compensation Discussion and Analysis be included in this Proxy Statement.

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This compensation committee report shall not be deemed to be “soliciting material,” or to be “filed” with the SEC or subject to Regulation 14A or 14C under the Exchange Act, other than as provided by applicable SEC rules, or to the liabilities of Section 18 of the Exchange Act, except to the extent that we specifically request that the information be treated as soliciting material or specifically incorporate it by reference into a document filed under the Securities Act or the Exchange Act. This compensation committee report will not be deemed to be incorporated by reference into any filing under the Securities Act or the Exchange Act, except to the extent that we specifically incorporate it by reference.

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EXECUTIVE COMPENSATION

Summary Compensation Table

The following table summarizes the total compensation awarded to, earned by or paid to each of our named executive officers for 2023, 2024 and 2025. Because the following tables are required to be presented as of December 31, 2025 and are not permitted to reflect the Chief Executive Officer Transition, the disclosures for Mr. Littlefair and Mr. Corbus reflect their 2025 compensation and roles as of the end of 2025.

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Grants of Plan-Based Awards

The following table summarizes all plan-based awards granted to each of the named executive officers in 2025:

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