Alcoa : 2026 Annual Meeting of Stockholders RULES OF CONDUCT

Welcome to the 2026 Annual Meeting of Stockholders ("Annual Meeting") of Alcoa Corporation ("Alcoa" or the "Company"). In fairness to all participants and in the interest of an orderly and constructive meeting, we ask that you abide by the following rules of conduct and procedures.

1. Authority to Conduct the Meeting: William F. Oplinger, President and Chief Executive Officer, will serve as Chairman of the Annual Meeting (the "Chairman") and has the authority to preside over the Annual Meeting and rule on any questions or procedural matters that may arise. Any action taken by the Chairman will be final and binding on all persons. The Chairman has the authority to speak for the entire Board of Directors (the "Board").

2. Attendance: Stockholders and holders of Chess Depository Interests ("CDIs") at the close of business on March 11, 2026 (EDT) may attend the Annual Meeting by visiting www.virtualshareholdermeeting.com/AA2026. Stockholders may attend the Annual Meeting by entering their 16-digit control number located on their proxy materials. CDI holders may attend the Annual Meeting by visiting www.virtualshareholdermeeting.com/AA2026 where they will be able to listen to the live meeting.

3. Proposals: The only business to be conducted at the Annual Meeting consists of the four proposals set forth in the Notice of 2026 Annual Meeting of Stockholders and Proxy Statement. Proposals will be addressed in the sequence indicated on the Agenda.

4. Voting:

   • Stockholders (other than stockholders in an Alcoa savings plan and CDI holders) of record may vote during the Annual Meeting. You do not need to vote at the meeting if you have already voted by telephone, internet, or mail. However, if you wish to change your vote, or if you have not previously voted, you may vote online during the meeting while the polls are open.

   • Stockholders in an Alcoa savings plan and CDI holders were required to provide their voting instructions to the trustee and CHESS Depositary Nominees Pty Ltd, respectively, in advance of the meeting.

   • If any item of the official business of the meeting is not properly presented at the meeting, votes on that item will not be counted.

5. Questions: Stockholders and CDI holders have had the opportunity to submit written questions prior to the meeting. At the meeting, once logged in to the virtual meeting platform at www.virtualshareholdermeeting.com/AA2026, stockholders (other than stockholders in an Alcoa savings plan and CDI holders) may submit a written question by typing it into the "Ask a Question" field, then clicking "Submit." Please provide your name and address (city and state) and organization when submitting a question.

   During the Question and Answer session, the Chairman will answer questions pertinent to meeting matters, including those received prior to the Annual Meeting from stockholders and CDI holders, as time permits. Please note that:

   • Any questions pertinent to meeting matters that cannot be answered during the meeting will be posted and answered on the Investors portion of our website at https://investors.alcoa.com as soon as practicable after the meeting.

   • To allow as many individuals as possible to ask questions, you will be limited to submitting a total of three questions prior to and during the meeting.

   • Questions from multiple stockholders and/or CDI holders on the same topic or that are otherwise related may be grouped, summarized, and answered together.

     (continued)

   • Alcoa does not intend to answer questions that are, among other things:

     • irrelevant to the business of Alcoa or to the business of the meeting;

     • related to general economic, political, or other issues that are not directly related to the business of Alcoa;

     • related to material non-public information of Alcoa;

     • related to personal grievances, individual personnel matters or a complaint about Alcoa's products or services;

     • derogatory references to individuals or Alcoa or that are otherwise inappropriate or in bad taste;

     • related to threatened or ongoing litigation;

     • repetitious questions or statements already submitted or made by another stockholder or made by the same stockholder at a prior annual meeting of the Company;

     • not a matter of interest to stockholders generally;

     • addressed in the Proxy Statement or in the Company's other public disclosures;

     • related to proposals or director nominations that were not previously submitted properly under Securities and Exchange Commission Rule 14a-8 or in accordance with the Company's advance notice or proxy access bylaw provisions, as applicable;

     • in furtherance of the stockholder's personal or business interests; or

     • out of order or not otherwise suitable for the conduct of the meeting as determined by the Chairman or Secretary in their reasonable judgment.

6. Individual Concerns: If there are any matters of individual concern, and not of general concern to all stockholders and CDI holders, or if a question posed was not otherwise answered, such matters or questions may be raised separately after the meeting by contacting Alcoa Investor Relations at https://investors.alcoa.com.

7. Issues During the Meeting:

   • If you encounter any difficulties accessing the meeting during the check-in or meeting time, please call 844-986-0822 (US) or 303-562-9302 (International) for assistance. Technical support will be available starting at 5:15 p.m. EDT on May 6, 2026 (7:15 a.m. AEST on May 7, 2026) through the conclusion of the meeting.

   • In the event of disorder, technical malfunction, or other significant problem that disrupts the meeting, the Chairman may adjourn, recess, or expedite the meeting or take such other action that the Chairman determines is appropriate in light of the circumstances. In such case, please stay connected to the meeting website for at least 15 minutes. If the meeting cannot be resumed, (i) all items of the official business of the meeting described in the Proxy Statement will be deemed to be properly presented before the meeting; (ii) all proxy and other votes received before the start of the interruption will be deemed to have been validly cast; and (iii) the official business of the meeting will be deemed to have been validly completed and the meeting adjourned immediately thereafter.

8. Prohibitions: Recording of the meeting is prohibited. Copying materials presented at the meeting, including screenshots and photographs, is also prohibited. The Company will make a replay of the webcast available approximately 24 hours after the end of the meeting on the Investors portion of our website at https://investors.alcoa.com and on www.virtualshareholdermeeting.com/AA2026.

Thank you for your cooperation and participation.