UNITED STATES

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the
Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): June 23, 2026

Registrant’s Telephone Number, Including Area Code: (833) 710-2586

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

Securities registered pursuant to Section 12(b) of the Act:

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

(e) On June 23, 2026, at the 2026 Annual Meeting of Stockholders of Alto Ingredients, Inc. (the “Company”), the Company’s stockholders approved the Alto Ingredients, Inc. 2026 Omnibus Incentive Plan (the “2026 Plan”). The 2026 Plan was previously approved by the Company’s Board of Directors, subject to stockholder approval.

The 2026 Plan provides for the grant of equity and equity-based awards, including stock options (which may be incentive stock options or nonqualified stock options), stock appreciation rights, restricted stock, restricted stock units, performance-based awards and other share-based and cash-based awards, to officers, non-employee directors, employees, consultants and advisors of the Company and its subsidiaries, including the Company’s named executive officers. The 2026 Plan is administered by the Compensation Committee of the Board of Directors, which has discretion to determine the individuals who receive awards, the types and amounts of awards granted, and the terms and conditions of such awards (including any performance goals). The maximum number of shares of the Company’s common stock that may be issued under the 2026 Plan is 7,000,000 shares, subject to adjustment for certain corporate events as described in the 2026 Plan. Unless earlier terminated in accordance with its terms, the 2026 Plan will remain in effect until June 23, 2036.

The foregoing description of the 2026 Plan does not purport to be complete and is qualified in its entirety by reference to the complete text of the 2026 Plan and the more detailed description of the 2026 Plan contained in the Company’s definitive proxy statement for the 2026 Annual Meeting of Stockholders, filed with the Securities and Exchange Commission on April 30, 2026 (the “Proxy Statement”), under the caption “Proposal Three – Approval of 2026 Omnibus Incentive Plan – Summary of the 2026 Plan,” each of which is incorporated herein by reference. A copy of the 2026 Plan is filed as Exhibit 10.1 to this Current Report on Form 8-K and is incorporated herein by reference.

The 2026 Annual Meeting of Stockholders of Alto Ingredients, Inc. (the “Annual Meeting”) was held on June 23, 2026. The following proposals were approved at the Annual Meeting by the votes indicated:

Proposal One: To elect five directors to serve on the Company’s board of directors until the next annual meeting of stockholders and/or until their successors are duly elected and qualified. The nominees for election were Gilbert E. Nathan, Bryon T. McGregor, Dianne S. Nury, Maria G. Gray and Alan R. Tank.

The following nominees were elected by the votes indicated to serve as directors until the next annual meeting of stockholders and/or until their successors are duly elected and qualified:

Proposal Two: To approve the 2025 compensation of the Company’s named executive officers, as disclosed in the proxy statement pursuant to the compensation disclosure rules of the Securities and Exchange Commission (“say-on-pay”).

Proposal Three: To approve the Company’s 2026 Omnibus Incentive Plan.

Proposal Four: To ratify the appointment of RSM US LLP as the Company’s independent registered public accounting firm for the year ending December 31, 2026.

(d) Exhibits.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.