American Public Education : 2023 Notice of Annual Meeting and Proxy Statement

Message from our Chairperson

April 5, 2023

Dear Stockholders:

We cordially invite you to join us for the 2023 Annual Meeting of Stockholders of American Public Education, Inc. to be held virtually on Friday, May 19th, 2023 at 8:30 a.m. EDT at www.virtualshareholdermeeting.com/ APEI2023. As a technology-enabled organization, a virtual meeting aligns with our commitment to innovation and our role as a provider of online education, and the virtual meeting will enable expanded stockholder participation for those who might not otherwise attend in person.

At the Annual Meeting, we will be asking you to elect ten director nominees named in the attached proxy statement to the Board of Directors. You will find detailed information beginning on page 25 about the qualifications of our director nominees and why we believe they are the right people to represent your interests. Our director nominees reflect our continued focus on good governance practices, board refreshment, and diversity and inclusion. All ten nominees are continuing directors, with two of the nominees up for election for the first time since their appointment.

The Board recognizes the importance of our financial results and value creation for stockholders, and the importance of focusing on the headwinds and operational challenges that we are addressing. In addition to those critical areas, the Board also remains committed to good corporate governance and our core values, which we believe are critical to long-term success. We continued to make progress on these governance fronts since the beginning of 2022, including by adding three new directors to our Board in alignment with our ongoing commitments to Board refreshment and a Board with a mix of backgrounds, experience, and perspectives, and by making best practices updates to numerous governance documents regarding diversity, related person transactions, and insider trading, among other topics.

As discussed in the Compensation Discussion and Analysis section, which begins on page 52, in 2022, we continued our commitment to compensation practices that are designed to attract, incentivize, retain, and reward the talent that we need to maintain and strengthen our position in career-minded adult education and to achieve our business objectives. At the Annual Meeting, we will be asking for approval, on a non-binding advisory basis, of our executive compensation and for stockholders to vote, on a non-binding advisory basis, for us to hold future advisory votes on executive compensation annually.

In addition to the election of directors, our annual advisory ''say-on-pay'' vote, and an advisory vote on the frequency of our future ''say-on-pay'' votes, we are also asking stockholders to approve amendments to our 2017 Omnibus Incentive Plan and Employee Stock Purchase Plan to increase the number of shares available for issuance thereunder, as discussed on pages 37 and 48, respectively. We strongly believe that equity ownership by our employees is critical to aligning the interests of our employees with our stockholders, and without additional shares it will be more challenging for us to drive employee and stockholder alignment given the competitive pressures in the market for new and existing executive talent.

As discussed beginning on page 97, our Audit Committee has again selected Deloitte & Touche LLP as our independent registered public accounting firm for the year ending December 31, 2023, and we will be asking you to ratify that appointment.

On behalf of the entire Board, I thank you for your continued support. We appreciate the opportunity to serve American Public Education on your behalf.

Sincerely,

Eric C. Andersen

Chairperson, Board of Directors

111 W. Congress Street

Charles Town, West Virginia 25414

NOTICE OF ANNUAL MEETING OF STOCKHOLDERS

The 2023 Annual Meeting of Stockholders of American Public Education, Inc. (the ''Annual Meeting'') will be held on May 19, 2023 at 8:30 a.m. Eastern Daylight Time as a virtual meeting of stockholders held over the Internet. Stockholders will be able to attend the Annual Meeting, vote, and submit questions during the Annual Meeting at www.virtualshareholdermeeting.com/APEI2023. The Annual Meeting will be held for our stockholders to consider and vote on the following proposals:

• Proposal No. 1: To elect to the Board, the 10 nominees set forth in the accompanying proxy materials, each of whom will hold office until the next annual meeting of stockholders and until such director's successor is elected and qualified or until such director's earlier death, resignation, or removal.
• Proposal No. 2: To approve an amendment to the American Public Education, Inc. 2017 Omnibus Incentive Plan, including, among other changes, to increase the number of shares available for issuance thereunder.
• Proposal No. 3: To approve an amendment to the American Public Education, Inc. Employee Stock Purchase Plan to increase the number of shares available for purchase thereunder.
• Proposal No. 4: To approve, on an advisory basis, the compensation of our named executive officers as disclosed in the accompanying proxy materials.
• Proposal No. 5: To approve, on an advisory basis, the frequency of future advisory votes on the compensation of our named executive officers.
• Proposal No. 6: To ratify the appointment of Deloitte & Touche LLP as our independent registered public accounting firm for the fiscal year ending December 31, 2023.