KAISER ALUMINUM CORP

(1)

Reflects (a) annual retainer of $90,000 and (b) any additional annual retainer for serving as Lead Independent Director or chair or member of a committee of the board of directors. Each non-employee director had the right to elect to receive shares of our common stock in lieu of any or all of his or her annual cash retainer, including retainers for serving as Lead Independent Director or a committee chair. In 2024: Mr. Arnold received 1,393 shares of common stock in lieu of $134,965 of his annual retainer; Mr. Grimley received 216 shares of common stock in lieu of $20,928 of his annual retainer; Mr. Hockema received 2,683 shares of common stock in lieu of $259,951 of his annual retainer; Ms. Martin elected to receive 1,310 shares of common stock in lieu of $126,923 of her annual retainer; Ms. Sebastian elected to receive 241 shares of common stock in lieu of $23,350 of her annual retainer; and Mr. Wilcox elected to receive 642 shares of common stock in lieu of $62,202 of his annual retainer. In each case, the number of shares received was determined based on a per share price of $96.89, the average of the closing prices per share of our common stock as reported on the Nasdaq Global Select Market for the 20 trading days prior to the award date of the annual retainers.

(2)

Reflects the aggregate grant date fair value of restricted stock awards to non-employee directors determined in accordance with ASC Topic 718, without regard to potential forfeiture. On June 11, 2024, in accordance with our director compensation policy described below, each non-employee director, other than Messrs. Hockema and Osborne, received a grant of restricted stock having a targeted value of $140,000; the average of the closing prices per share of our common stock as reported on the Nasdaq Global Select Market for the 20 trading days prior to the award date was $96.89, resulting in the issuance of 1,444 shares of restricted stock to each non-employee director. For additional information regarding the assumptions made in the valuation of restricted stock awards with respect to our 2024 fiscal year, see Note 7 of the Notes to Consolidated Financial Statements included in our Annual Report on Form 10-K for the fiscal year ended December 31, 2024. As of December 31, 2024, each non-employee director held 1,444 shares of restricted stock. The restrictions on 100% of the shares of restricted stock granted to non-employee directors will lapse on June 11, 2025 or earlier if the director's services to our company terminate as a result of disability or death, or in the event of a change in control. Each non-employee director will receive all dividends and other distributions paid with respect to the shares of restricted stock the director holds, but if any of such dividends or distributions are paid in shares of our capital stock, such shares will be subject to the same restrictions on transferability as are the shares of restricted stock with respect to which they were paid.

(3)

Reflects dividends received on restricted stock for all directors other than Mr. Hockema. For Mr. Hockema, the amount reflects an automotive allowance in the amount of $14,570. As previously disclosed, Mr. Hockema transitioned from CEO to Executive Chairman of the Board in July 2020 and retired from our board in January 2025.

(4)

Dr. Osborne retired from our board on June 11, 2024 and did not receive an annual or equity retainer for the 2024-2025 service period.