UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

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Kaiser Aluminum Corporation

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LETTER TO OUR STOCKHOLDERS

FROM OUR CHAIRMAN OF THE BOARD, PRESIDENT AND CHIEF EXECUTIVE OFFICER

AND OUR LEAD INDEPENDENT DIRECTOR

April 28, 2025

Dear Stockholder:

On behalf of our Board of Directors and management team, we thank you for your continued support of Kaiser Aluminum Corporation. It is our pleasure to invite you to attend the Annual Meeting of Stockholders to be held at the Company's corporate office at 1550 West McEwen Drive, Suite 500, Franklin, Tennessee 37067, on Tuesday, June 10, 2025, at 9:00 a.m. Central Time. While we do not expect to make a separate presentation, we expect our directors and officers to be present at the Annual Meeting and available to respond to any questions you may have.

Your vote is very important to us. Whether or not you plan to attend the Annual Meeting, we urge you to vote your shares as promptly as possible. Details of the business to be conducted at the Annual Meeting are included in this Proxy Statement, which we encourage you to read carefully. You may submit your voting instructions over the Internet or by telephone as indicated on the enclosed proxy card or by completing, signing and dating the enclosed proxy card and returning it by mail in the accompanying envelope. If you plan to attend the Annual Meeting, please review the information on attendance provided in this Proxy Statement.

We would like to share with you several areas of particular significance in advance of our Annual Meeting and in connection with our distribution of this Proxy Statement:

2024 PERFORMANCE HIGHLIGHTS

As we reflect on 2024, we are proud of the efforts and dedication of our team and our performance, particularly our continued margin expansion, which was achieved in a highly complex market environment, as we continued to position Kaiser for the future. In addition, throughout the year, we remained steadfast in our commitment to meeting the evolving needs of our customers— a foundational principle that continues to drive our success.

Our 2024 net sales and conversion revenue of $3.02 billion and $1.46 billion, respectively, met our expectations, despite navigating a highly complex and rapidly changing market environment. Additionally, we were pleased to report 2024 net income of $66 million, or $4.02 per diluted share, along with adjusted earnings before interest, taxes, depreciation, and amortization (adjusted EBITDA) of $241 million. This resulted in a strengthened adjusted EBITDA margin (which is calculated as adjusted EBITDA as a percentage of conversion revenue) over the prior year. Effective January 1, 2025, we elected to change our method of accounting for certain inventory from the last-in, first-out ("LIFO") method to the weighted average cost ("WAC") method to improve the comparability of our operational results between periods by removing LIFO income or charge in a period resulting from LIFO valuation and changes to historical LIFO layers. This change has been retrospectively applied to the financial information presented in this Letter to our Stockholders. Please refer to “Appendix A” of this Proxy Statement for reconciliations of measures from generally accepted accounting principles (“GAAP”) measures to non-GAAP measures such as conversion revenue, adjusted EBITDA and adjusted EBITDA margin.

As a key supplier of highly engineered solutions used in diverse end market applications including aerospace and high-strength, packaging, general engineering, automotive extrusions, and other industrial applications, our niche areas of focus have only strengthened our competitive position. While each of our end markets presented unique challenges in 2024, we responded with resilience and determination, working diligently to meet the growing demand from our customers. At Kaiser, maintaining long-term customer relationships goes beyond high-quality products, on-time delivery, and superior customer satisfaction. It is rooted in a deep understanding of our customers’ evolving needs, including positively contributing to their approaches to sustainability. The mutual commitments we have built with our customers over the years serve as a foundation for guiding our business decisions and priorities.

In response to these growing needs, in 2020 we initiated a significant multi-year investment cycle across our portfolio, which we believe positions the Company to seize future opportunities and sustain our momentum for continued growth. These investments included upgrading our acquired Warrick rolling mill to convert approximately 25% of our existing mix to higher-margin coated products for packaging customers. Further, we are expanding capacity at our Trentwood rolling mill by approximately 5% to support anticipated stronger demand for high-value flat-rolled products for aerospace and general engineering applications. This investment is the start of our next major Phase VII expansion at Trentwood.

CORPORATE VALUES & SUSTAINABILITY

Our corporate values of being a preferred investment, a preferred supplier, a preferred employer, a preferred customer, and a valued corporate citizen define how we pursue sustainable business value and serve as the foundation of our culture and strategy. In 2024, we:

SUMMARY

In summary, we are extremely proud of the work our team has done to position the Company for an expected significant performance inflection, while remaining steadfast in our commitment to meet our customers’ needs. Looking ahead, we anticipate a stabilization in market conditions with all of our markets presenting strong, secular growth opportunities. We are eager for our stakeholders to benefit from the largest capital investment cycle in Kaiser’s recent history and are excited to bring key investments online to meet growing market demand. We remain confident in our ability to achieve sustainable, long-term growth, guided by our five corporate values.

We are committed to managing our business for long-term success in a way that is economically, environmentally, and socially responsible, ensuring that we remain a good corporate citizen and a steward of both capital and resources. Thank you to our stockholders, our employees and their families, our customers, our suppliers and our other stakeholders for their ongoing commitment to and support of Kaiser Aluminum.

Kaiser Aluminum Corporation

1550 West McEwen Drive, Suite 500

Franklin, Tennessee 37067

NOTICE OF ANNUAL MEETING OF STOCKHOLDERS

TO BE HELD ON June 10, 2025

NOTICE IS HEREBY GIVEN that the 2025 Annual Meeting of Stockholders (the "Annual Meeting") of Kaiser Aluminum Corporation (the "Company") will be held at the Company's corporate office, located at 1550 McEwen Drive, Suite 500, Franklin, Tennessee 37067, on Tuesday, June 10, 2025, at 9:00 a.m., Central Time, for the following purposes:

Information concerning the matters to be acted upon at the Annual Meeting is set forth in the accompanying Proxy Statement. This notice and the accompanying proxy materials are being mailed or made available to stockholders on or about April 28, 2025.

The close of business on April 17, 2025 has been fixed as the record date for determining the stockholders entitled to notice of, and to vote at, the Annual Meeting or any adjournments thereof.

We urge stockholders to vote by proxy by submitting voting instructions over the Internet or by telephone as indicated on the enclosed proxy card or by completing, signing and dating the enclosed proxy card and returning it by mail in the accompanying envelope, which does not require postage if mailed in the United States.

PROPOSALS AND BOARD RECOMMENDATIONS

Proposal 1 - Election of Directors

The board of directors recommends a vote "FOR ALL" of the persons nominated by the board of directors.

Additional information about each director and his and her qualifications may be found beginning on page 5.

Proposal 2 - Advisory Vote to Approve Named Executive Officer Compensation

The board of directors recommends a vote "FOR" the approval, on a non-binding, advisory basis, of the compensation of our named executive officers as disclosed in this Proxy Statement.

Additional information about executive compensation may be found beginning on page 12.

Proposal 3 - Ratification of Appointment of Independent Registered Public Accounting Firm

The board of directors recommends a vote "FOR" the ratification of the audit committee's selection of Deloitte & Touche LLP as our independent registered public accounting firm for 2025.

Additional information about the independent registered public accounting firm may be found beginning on page 15.

PROXY STATEMENT SUMMARY

In 2024, we delivered solid performance, including continued margin expansion, despite a highly complex and dynamic market environment. This summary highlights information contained elsewhere in this Proxy Statement but does not contain all of the information that you should consider. We encourage you to read the entire Proxy Statement for more information about these topics prior to voting.

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EXECUTIVE COMPENSATION HIGHLIGHTS

Our incentive programs are designed to “pay for performance,” and it is expected that payouts may be impacted during difficult business/economic conditions. As described in further detail in the “Executive Compensation - Compensation Discussion and Analysis” section of this Proxy Statement, or CD&A, our 2024 compensation program was developed and designed to:

In 2024, the compensation of our named executive officers consisted primarily of the following components:

Because grants under our long-term incentive program are outstanding for three years, at any time we have three over-lapping long-term incentive programs outstanding. The underlying metrics applicable to the performance shares can vary as our compensation committee assesses the effectiveness of our outstanding programs, metrics critical to our long-term success, feedback from our stockholders and compensation trends. The following table describes the performance share metrics (described more fully below) for our 2022-2024, 2023-2025 and 2024-2026 long-term incentive programs:

The compensation committee, working with its independent compensation consultant, Meridian Compensation Partners, LLC (referred to herein as Meridian), reviews, evaluates and updates our compensation peer group, which includes companies in both similar and different industries, at least annually. For 2024, the compensation committee approved a 23-company peer group more fully described in our CD&A section. Due to the differences in size among the companies in our peer group, Meridian uses a regression analysis to adjust survey data results based on our revenue as compared to the revenue of other companies in our peer group.

Pay for Performance

The table below summarizes the performance metrics under our 2024 short-term incentive plan ("2024 STI Plan") and 2024-2026 long-term incentive plan ("2024-2026 LTI Plan") for our named executive officers:

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* Safety performance is measured using our total case incident rate ("TCIR") and lost-time case incident rate ("LCIR"). Quality performance is measured using our no-fault claim rate. Delivery performance is measured by our on-time delivery rate.

** As noted, the individual modifier is discretionary and, with respect to our executive officers, only used in exceptional instances approved by the compensation committee based on actual performance, including individual, facility and/or functional area performance, as well as performance against other strategic initiatives.

The following summarizes the key features and our performance against the metrics under our 2024 STI Plan and our 2022-2024 long-term incentive plan ("2022-2024" LTI Plan"):

2024 STI Plan

The final multiplier of our 2024 STI Plan, including the impact of all performance metrics, was 0.95x. The table below summarizes the performance metrics and payout potential under our 2024 STI Plan and our performance against each of the metrics:

__________________________

*Total may not sum due to rounding.

Annual Performance Award Payouts under Short-Term Incentive Plans for our Named Executive Officers

2022-2024 LTI Plan

As discussed in more detail below, for the 2022 to 2024 performance period, the impact of challenging business conditions and operational challenges significantly and negatively impacted our ability to achieve the required level of performance for our Adjusted

EBITDA margin performance metric under the 2022-2024 LTI Plan. Accordingly, no performance shares were earned based on our Adjusted EBITDA margin performance over the 2022-2024 performance period, while our relative TSR performance resulted in a total payout of 44% under the 2022-2024 LTI Plan.

Annual Performance Award Payouts under Long-Term Incentive Plans

The table below reflects our annual performance award payouts for the last three years under our completed long-term incentive plans.

Performance Share Award Payouts Based on Relative TSR

For our 2022-2024 LTI Plan, 60% of the performance shares granted to our named executive officers were subject to our TSR performance metric over the applicable three-year performance period compared to the TSR of the other companies comprising the S&P SmallCap 600 Materials and S&P MidCap 400 Materials Indices.

In considering constituents for the S&P SmallCap 600 Materials and S&P MidCap 400 Materials Indices, S&P Dow Jones Indices currently looks for companies (1) with market capitalization of between $1.1 billion and $7.4 billion and between $7.4 billion and $20.5 billion, respectively, (2) meeting certain float requirements, (3) with a U.S. domicile, (4) required to file Securities and Exchange Commission ("SEC") annual reports, and (5) listed on a major U.S. exchange, among other factors. The beginning and ending stock prices used to determine our TSR are calculated using the 20-trading day average preceding the beginning and end of the performance period. Based on our relative TSR performance for the 2022-2024 performance period, the multiplier for such metric was 74%, resulting in a final multiplier of 0.44x.

The chart below illustrates the relative TSR performance payout multipliers for our performance share awards under the 2020-2022, 2021-2023 and 2022-2024 long-term incentive programs:

Performance Share Award Payout Based on Adjusted EBITDA Margin

For our 2022-2024 LTI Plan, 40% of the performance shares granted to our named executive officers were subject to an Adjusted EBITDA margin performance metric, calculated by our Adjusted EBITDA as a percentage of conversion revenue over the three-year performance period. Our conversion revenue is calculated as our net sales less the hedged cost of alloyed metals.

For the 2022 to 2024 performance period, our adjusted EBITDA margin was negatively impacted by a number of factors, including (i) supply chain challenges, such as the impact of the declaration of force majeure by Warrick’s primary magnesium supplier and ultimately the cessation of all magnesium deliveries from that supplier that led to our declaration of force majeure at Warrick in 2022, (ii) molten metal supply issues that negatively impacted Warrick, (iii) the inflationary environment and significant corresponding increases in costs, (iv) a planned outage at Trentwood in 2022, and (v) a challenging labor market. As a result, despite our improved performance in 2023 and 2024, we did not achieve the threshold Adjusted EBITDA margin required for a payout and no performance shares were earned under the Adjusted EBITDA margin metric.

2024 Total CEO Compensation

As previously noted, the mix of our CEO’s total target compensation is heavily weighted toward performance-based compensation with more than 80% of the total target compensation being at-risk (short- and long-term compensation), more than 60% of the total target compensation being long-term, and 50% of the long-term target being allocated to performance shares.

The market pay analysis performed by Meridian at the end of 2024 reflected that the total target compensation of our CEO for 2024 was 13% below the median of our compensation peer group and that our CEO’s (1) base salary was approximately 5% below the median base salary, (2) short-term incentive target was approximately 9% below the median and (3) long-term incentive target was approximately 15% below the median. While stronger performance in 2024 resulted in a 0.95x payout to our CEO under our 2024 STI Plan, the payout to our CEO under our long-term incentive program was further impacted by the challenging business conditions and operational challenges described above during the 2022-2024 performance period, resulting in only 44% of the performance shares being earned. As previously discussed, although the payout under our long-term incentive program, including the payout to our CEO, was significantly impacted by the challenging business conditions and operational challenges, based on management’s recommendation, the compensation committee did not make any adjustments to our existing long-term incentive program or the underlying payout.

Kaiser Aluminum Corporation

1550 West McEwen Drive, Suite 500

Franklin, Tennessee 37067

PROXY STATEMENT

FOR

ANNUAL MEETING OF STOCKHOLDERS

To Be Held on June 10, 2025

TABLE OF CONTENTS

Important Notice Regarding the Availability of Proxy Materials for the Annual Meeting of Stockholders to be held on June 10, 2025: The Proxy Statement and our Annual Report to Stockholders are available at www.envisionreports.com/kalu.

GENERAL QUESTIONS AND ANSWERS

PROPOSALS REQUIRING YOUR VOTE

Proposal 1 - Election of Directors

General

We have a diverse and highly independent board of directors. Our board of directors currently has 10 members, consisting of our CEO and nine independent directors.

Our current directors are:

_____________

* Ms. Sebastian will not stand for reelection at the Annual Meeting.

Our board of directors represents a breadth of experience and diversity in perspective and background, as reflected in the summary of their collective qualifications below. Additionally, our directors have a broad range of tenures, from less than one year to approximately 18 years of service, with an average tenure of approximately seven years. We believe this diversity balances institutional knowledge and experience with new perspectives and ideas.

The table below sets forth the knowledge, skills or board experience, demographics and board tenure of our directors as of April 28, 2025:

Our amended and restated certificate of incorporation and bylaws provide for a classified board of directors consisting of three classes. The term of our Class I directors expires at the Annual Meeting; the term of our Class II directors will expire at the 2026 annual meeting of stockholders; and the term of our Class III directors will expire at the 2027 annual meeting of stockholders.

Board Refreshment and Director Succession Planning

We are committed to board refreshment. Currently, 70% of our directors have a tenure of less than six years. The table below illustrates the tenure of our directors:

We thoughtfully plan for director succession and board refreshment. By developing and following a long-term succession plan, the board has an ongoing opportunity to:

The nominating and corporate governance committee also plans for the orderly succession of the executive chair, independent lead director and each of the chairs of our board's five committees, providing for the identification of potential successors, their development and the transition of responsibilities. As a result of the management and execution of our board’s succession plans, a leadership transition of our board’s executive chair position occurred earlier this year when Mr. Harvey became chairman of the board.

Board Composition

Bringing together informed directors with different perspectives and backgrounds, in a well-managed and constructive environment, fosters thoughtful and innovative decision-making. We have a policy of encouraging diversity of gender, ethnicity, age and background, as well as a range of tenures on the board to ensure both continuity and fresh perspectives among our directors. Our directors exhibit a balanced mix of tenures, ages, independence and diversity.

Nominees for Class I Directors

The nominating and corporate governance committee of our board of directors has recommended, and our board of directors has approved, the nomination of the three nominees listed below. The nominees have indicated their willingness to serve as members of the board of directors if elected; however, in case any nominee becomes unavailable for election to the board of directors for any reason not presently known or contemplated, the proxy holders have discretionary authority to vote proxies for a substitute nominee. Proxies cannot be voted for more than three nominees.

The Board of Directors Recommends a Vote "FOR ALL" of the Persons Nominated by the Board of Directors.

Set forth below is information about the Class I director nominees, including their ages, present principal occupations, other business experience, directorships in other public companies in the past five years, membership on committees of our board of directors, and reasons why each individual nominee's specific experience, qualifications, attributes and skills led the nominating and corporate governance committee to recommend, and our board of directors to conclude, that the nominee should serve as a director of the Company.

Continuing Directors

Set forth below is information about our continuing directors, including their ages, present principal occupations, other business experiences, directorships in other public companies in the past five years, membership on committees of our board of directors, and reasons why each individual director's specific experience, qualifications, attributes or skills led our board of directors to conclude that the director should serve on our board of directors.

Class II Directors – Term Expiring at the 2026 Annual Meeting

Class III Directors – Term Expiring at the 2027 Annual Meeting

Proposal 2 - Advisory Vote to Approve Named Executive Officer Compensation

In accordance with the Dodd-Frank Wall Street Reform and Consumer Protection Act, or the Dodd-Frank Act, and Section 14A of the Securities Exchange Act of 1934, referred to herein as the Exchange Act, we ask our stockholders to vote annually on a non-binding, advisory resolution to approve our named executive officer compensation. The vote is not intended to address any specific component of our executive compensation program, but rather the overall compensation of our named executive officers as described in this Proxy Statement. The text of the resolution is as follows:

RESOLVED, that the compensation paid to the named executive officers of Kaiser Aluminum Corporation, as described in the proxy statement for the Company's 2025 annual meeting of stockholders pursuant to Item 402 of Regulation S-K (which disclosure includes the "Executive Compensation - Compensation Discussion and Analysis" section and the Summary Compensation Table and other compensation tables and related narrative discussions), is hereby APPROVED.

Our performance in 2024 resulted in a 0.95x payout under our 2024 STI Plan. The challenging business conditions and operational challenges during the 2022-2024 performance period negatively impacting our financial and relative TSR performance during that time period, resulting in a 0.44x payout of performance shares under our 2022-2024 LTI Plan. Despite these conditions and challenges, the compensation committee, based on our management's recommendation, did not make any adjustments to our existing incentive programs. Our incentive programs are designed to “pay for performance,” and it is expected that payouts may be impacted during difficult business/economic conditions. Accordingly, we determined that it was appropriate to maintain our existing incentive programs without adjustments that would otherwise mitigate the impact of the challenges we experienced on the payouts under our incentive plans.

As described in further detail in the CD&A section, our compensation structure was developed to achieve the following objectives, which we believe are critical for enhancing stockholder value and our long-term success and sustainability:

The compensation committee reviewed our compensation program for 2024. The review included consideration of stockholder feedback, including approval of prior advisory votes to approve our named executive officer compensation, and discussions with Meridian and management regarding existing and contemplated market practices, as well as the structure and objectives of each component of our compensation. Upon completion of that review, the compensation committee determined that the compensation of our named executive officers in 2024 would consist primarily of the following components:

The compensation committee, working with Meridian, reviews, evaluates and updates our compensation peer group, which includes companies in both similar and different industries, at least annually. For 2024, the compensation committee approved a 23-company peer group more fully described in our CD&A section. As of November 2023, the new custom peer group had (1) market capitalization ranging from approximately $240 million to approximately $21.2 billion and a median market capitalization of approximately $4.4 billion, and (2) trailing 12 months revenues ranging from approximately $2.0 billion to approximately $8.8 billion and median revenue of approximately $3.6 billion. Our market capitalization and revenue, both as of December 31, 2023, were $1.1 billion and $3.1 billion, respectively. Due to the differences in size among the companies in our peer group, Meridian uses a regression analysis to adjust survey data results based on our revenue as compared to the revenue of other companies in our peer group.

We no longer maintain a defined benefit pension plan or retiree medical program that covers members of senior management. Retirement benefits for our senior management, including our named executive officers, are provided through a defined contribution retirement program consisting of a 401(k) plan (which we refer to as our Savings Plan) and a nonqualified and unsecured deferred compensation plan (which we refer to as our Restoration Plan) intended to restore benefits that would be payable to designated participants in our Savings Plan but for the limitations on benefit accruals and payments imposed by the Internal Revenue Code of 1986, as amended (referred herein as the Code).

For 2024, over 80% of the target total compensation of our CEO and approximately 60% to 70% of the target total compensation of our other named executive officers, consisted of at-risk compensation, which we define as compensation that either (1) will be realized, if at all, only if certain performance levels are achieved as in the case of our annual short-term incentive and the portion of our long-term incentive consisting of performance shares or (2) is time-based as in the case of the portion of our long-term incentive compensation consisting of restricted stock units.

Our compensation structure also supports our corporate governance practices, which further align the interests of senior management and our stockholders. The table below sets forth the best practice compensation features we have adopted as of 2024.

Best Practice Compensation Features

We believe our incentive compensation programs are designed to demand continuous improvement. We also believe that design emphasizing the importance of successful execution of each of our six key strategic initiatives is important to our long-term success and aligns the interests of our named executive officers with our stockholders. Our key strategic initiatives are to:

We urge our stockholders to review our CD&A which describes our compensation philosophy and programs in detail and to approve the compensation of our named executive officers. While this vote to approve our named executive officer compensation is non-binding and solely advisory in nature, our board of directors and the compensation committee value the opinions of our stockholders and expect to consider the outcome of the vote when determining future executive

compensation programs. We hold this advisory vote to approve our named executive officer compensation on an annual basis, and the next such vote is expected to be conducted at our 2026 annual meeting.

The board of directors recommends a vote "FOR" the approval, on a non-binding, advisory basis, of the compensation of our named executive officers as disclosed in this Proxy Statement.

Proposal 3 - Ratification of the Selection of our Independent Registered Public Accounting Firm

Pursuant to the audit committee charter, the audit committee has the sole authority to retain an independent registered public accounting firm for our company. The board of directors requests that the stockholders ratify the audit committee's selection of Deloitte & Touche LLP as our independent registered public accounting firm for 2025.

The audit committee will not be bound by the ratification of, or failure to ratify, the selection of Deloitte & Touche LLP, but the audit committee will consider any failure to ratify the selection of Deloitte & Touche LLP in connection with the appointment of our independent registered public accounting firm for 2026.

The board of directors recommends a vote "FOR" the ratification of the audit committee's selection of Deloitte & Touche LLP as our independent registered public accounting firm for 2025.

CORPORATE GOVERNANCE

Our board of directors is responsible for providing effective governance over the affairs of our company. Our corporate governance practices are designed to align the interests of our board of directors and management with those of our stockholders and to promote honesty, integrity and our corporate values throughout the Company. Highlights of our corporate governance practices are described below.

A copy of the current charter, as approved by our board of directors, for each of the executive committee, audit committee, compensation committee, nominating and corporate governance committee and sustainability committee, and a copy of each of our corporate governance guidelines and our code of business conduct and ethics, which applies to all of our directors and employees, including our executive officers, are available on our website at www.kaiseraluminum.com under "Investors - Governance." Furthermore, we will post any amendments to our code of business conduct and ethics, or waivers of the code for our directors or executive officers, on our website at www.kaiseraluminum.com under "Investors- Governance."

Corporate Governance Highlights

Highlights of our corporate governance practices are described below:

Board Leadership Structure

In January 2025, in connection with the retirement of Jack A. Hockema from our board, Mr. Harvey, our President and CEO was appointed Chairman. Mr. Arnold serves as the Lead Independent Director of our board. We believe Mr. Harvey's substantial experience with our company and its business, the independence of the other directors, our governance structure and the interaction between and among Messrs. Harvey and Arnold and the other directors make our board leadership structure the most appropriate for our company and our stockholders.

Our corporate governance guidelines and governance structure require a Lead Independent Director to be selected by a majority of the independent directors when the position of CEO and Chairman of the board are combined or the Chairman of the board is otherwise not an independent director, thereby ensuring that there is independent leadership within our board of directors and allowing our independent directors to function as a body distinct from management and evaluate the performance of our CEO and management independently and objectively. The responsibilities of our Lead Independent Director include:

Each of the audit, compensation, nominating and corporate governance and sustainability committees consists solely of independent directors. The chair of each committee serves as a liaison to keep our full board of directors and our CEO apprised of the work performed by their respective committees at each of our regularly scheduled board meetings and as otherwise required. Finally, under our bylaws, special meetings of our board of directors may be called by the Chairman, our CEO or a majority of our board members.

Under our corporate governance guidelines, each member of our board of directors may submit items to be included on the agenda for any meeting of our board of directors and raise topics that are not on the agenda at any meeting of our board of directors. In addition, our independent directors, representing nine of our 10 directors, are required to meet at least quarterly in executive sessions at which only independent directors are present. Additionally, we encourage direct communication among our directors and with our CEO before, during and after formal board and committee meetings and facilitate those communications around all of our meetings. Our directors also have full access to our officers, employees and advisors.

Risk Oversight

We have policies in place to identify, assess and manage potential risks and to continually review the procedures that we have designed and implemented to mitigate those risks. We believe that our board of directors provides effective oversight of the risk management function. Under its charter, the audit committee of our board of directors is responsible for discussing our risk management policies, including, without limitation, the steps taken and to be taken to monitor and control our major financial risk exposures. The audit committee also reviews risks relating to our information technology systems, including

cybersecurity. The compensation committee of our board of directors is responsible for assessing risks associated with our compensation policies and incentivizing the conduct of our business in a manner consistent with our corporate values and implementing our clawback policies. The nominating and corporate governance committee of our board of directors is responsible for evaluating our corporate governance structure, reviewing our directors, managing board succession planning and reviewing and evaluating the succession planning of our CEO and other executive officers. The sustainability committee of our board of directors is responsible for overseeing certain sustainability-related risks, including overseeing our overall approach to sustainability principles and related disclosures, reviewing and evaluating our leadership and development training, and reviewing the diversity of our management and workforce and our approach to recruiting and retaining our employees in accordance with our corporate values. Our Executive Vice President and Chief Financial Officer, working with a committee of other members of senior management, oversees our climate-related risk management approach and report regularly to the sustainability committee and the full board of directors on such matters.

In addition, our full board of directors is actively engaged in the review and assessment of our risk management policies, conducts a comprehensive review at least annually during a regularly scheduled board meeting and routinely requests that specific risk-related items be included on board and committee meeting agendas. We also engage in an ongoing enterprise risk management process pursuant to which we formally identify, categorize and assess our risks and risk mitigation strategies and routinely update the audit committee and the full board of directors regarding this process.

Director Independence

Our corporate governance guidelines require that a majority of the members of our board of directors satisfy the independence requirements set forth in the rules of the Nasdaq Stock Market. We refer to these requirements as the general independence criteria. Additionally, the audit committee charter, compensation committee charter and nominating and corporate governance committee charter require that all respective committee members satisfy the general independence criteria. There are no family relationships among our officers or directors.

Based upon information requested from and provided by our directors concerning their backgrounds, employment and affiliations, including family relationships, our board of directors has determined that each of Mmes. Glas, Martin and Sebastian and Messrs. Arnold, Foster, Grimley, Stebbins, Wilcox and Williams, representing nine of our 10 directors, satisfies the general independence criteria. The remaining director, Mr. Harvey, does not meet the independence criteria as our CEO. In making such determination, our board of directors considered the relationships that each of our directors have with our company and all other facts and circumstances our board of directors deemed relevant in determining the independence of each of our directors in accordance with the general independence criteria.

Director Designation Agreement

On July 6, 2006, we entered into a Director Designation Agreement with the USW under which the USW has certain rights to designate board candidates for nomination. We believe that:

Accordingly, in connection with the renewal and ratification of a new five-year collective bargaining agreement with members of the USW at our Spokane Valley, Washington and Newark, Ohio facilities, in April 2025, the Director Designation Agreement which was set to expire on December 31, 2025 was extended to December 31, 2030. Under the Director Designation Agreement, as amended, the USW generally has the right to designate for nomination the minimum number of director candidates necessary to ensure that, assuming the nominated candidates are elected by our stockholders, at least 40% of the members of our board of directors have been nominated by the USW.

The Director Designation Agreement contains requirements as to the timeliness, form and substance of the notice the USW must give to the nominating and corporate governance committee in order to nominate candidates. The nominating and corporate governance committee is required to determine in good faith whether each properly submitted candidate

satisfies the qualifications set forth in the Director Designation Agreement. Pursuant to the terms of the Director Designation Agreement, if the nominating and corporate governance committee determines that a nominated candidate satisfies the qualifications, the committee will, unless otherwise required by its fiduciary duties, recommend the candidate to our board of directors for inclusion in the slate of directors to be recommended by the board of directors in our proxy statement. Similarly, the board of directors will, unless otherwise required by its fiduciary duties, accept the designation for nomination and include the candidate in the slate of directors that the board of directors recommends. Notwithstanding the foregoing, the USW may not nominate an incumbent candidate without our approval.

In addition, the Director Designation Agreement provides that, so long as our board of directors maintains an audit committee, executive committee or nominating and corporate governance committee, each of these committees will, unless otherwise required by the fiduciary duties of our board of directors, include at least one director nominated by the USW (provided at least one director nominated by the USW is qualified to serve on the applicable committee as determined in good faith by our board of directors). Current members of our board of directors nominated by the USW prior to this Annual Meeting are Messrs. Foster, Grimley and Wilcox and Ms. Sebastian.

Board Committees

Currently, our board of directors has five standing committees: an executive committee; an audit committee; a compensation committee; a nominating and corporate governance committee; and a sustainability committee.

The following table sets forth the chair and members of each committee of our board of directors and the number of meetings each committee held during 2024.

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Executive Committee

The executive committee of our board of directors manages our business and affairs requiring attention prior to the next regular meeting of our board of directors. However, the executive committee does not have the power to (1) approve or adopt, or recommend to our stockholders, any action or matter expressly required by law to be submitted to our stockholders for approval, (2) adopt, amend or repeal the bylaws of our company, or (3) take any other action reserved for action by our board of directors pursuant to a resolution of our board of directors or otherwise prohibited to be taken by the executive committee by law or pursuant to our amended and restated certificate of incorporation or bylaws.

The executive committee charter requires that a majority of the members of the executive committee satisfy the general independence criteria. In addition, the members of the executive committee must include the chairman of our board of directors and at least one of the directors nominated by the USW. The executive committee is currently comprised of our CEO and chairman, lead independent director and the chair of each of the other standing committees of the board of directors.

Audit Committee

The audit committee of our board of directors oversees our accounting and financial reporting practices and processes and the audit of our financial statements on behalf of our board of directors. The audit committee is responsible for appointing, compensating, retaining and overseeing the work of our independent accounting firm. Other duties and responsibilities of the audit committee include:

The audit committee charter requires that all members of the audit committee satisfy the general independence criteria. The charter also requires that no audit committee members may have participated in the preparation of our financial statements during the three years prior to their appointment as a member and that each audit committee member be able to read and understand fundamental financial statements, including a balance sheet, an income statement and a cash flow statement. Additionally, at least one member of the audit committee must have had past employment experience in finance or accounting, requisite professional certification in accounting or any other comparable experience which results in that individual's financial sophistication, including being or having been a chief executive officer, chief financial officer or other senior officer with financial oversight responsibilities, and that member or another member must have sufficient education or experience to have acquired the attributes necessary to meet the criteria of an "audit committee financial expert," as that term is defined in the rules promulgated by the SEC. In addition, the members of the audit committee must include at least one of the directors nominated by the USW so long as at least one director nominated by the USW is appropriately qualified.

Our board of directors has determined that all members of the audit committee during 2024 (1) met the general independence criteria, the heightened independence criteria for members of the audit committee set forth in the rules of the Nasdaq Stock Market and the criteria for independence set forth in Rule 10A-3(b)(1) under the Exchange Act, and (2) are able to read and understand fundamental financial statements. Our board of directors has also determined that no member of the audit committee participated in the preparation of our financial statements during the three years prior to their appointment as members of the committee. Finally, our board of directors has determined that each member of the audit committee satisfies the financial sophistication criteria described above and satisfies the criteria necessary to serve as the "audit committee financial expert," in each case based on his or her experience described in "Proposals Requiring Your Vote - Proposal 1 - Election of Directors" above.

Compensation Committee

General

The compensation committee of our board of directors establishes and administers our policies, programs and procedures for compensating our senior management, including determining and approving the compensation of our executive officers. Other duties and responsibilities of the compensation committee include:

The compensation committee solicits the views of our CEO on compensation matters, including as they relate to our compensation of our executive officers and other members of senior management, including those reporting to our CEO. The compensation committee has retained Meridian to advise the compensation committee on all matters related to compensation of our CEO and other members of senior management. The compensation committee has reviewed the factors that could affect, and has assessed, Meridian's independence. Based on this review, the compensation committee has determined there are no conflicts of interest that have been raised by Meridian's work.

Meridian's services include (1) providing competitive market data and related assessments of executive compensation as background against which the compensation committee considers executive compensation, (2) preparing and reviewing tally and compensation summary sheets for our named executive officers, (3) apprising the compensation committee of trends and best practices associated with executive and director compensation, (4) providing support with respect to legal, regulatory and accounting considerations impacting compensation and benefit programs, (5) the development and review of a list of compensation peer group companies, and (6) attending meetings of the compensation committee and our board of directors when requested. These services are typically directed by the compensation committee and coordinated with our human resources and legal departments.

The compensation committee charter requires that all members of the compensation committee satisfy the general independence criteria and the heightened independence criteria for members of the compensation committee set forth in the rules of the Nasdaq Stock Market, as well as qualify as "non-employee directors" within the meaning of Rule 16b-3 promulgated under the Exchange Act. Our board of directors has determined that all members of the compensation committee during 2024 met the applicable independence criteria.

The compensation committee may create one or more subcommittees, each subcommittee to consist of one or more members of the committee, and may delegate to the subcommittee any or all of the powers and authority of the committee.

Compensation Committee Interlocks and Insider Participation

The following individuals served on the compensation committee during 2024: Donald J. Stebbins, Richard P. Grimley, Lauralee E. Martin, Brett E. Wilcox, and Kevin W. Williams. None of the members of the compensation committee during 2024, (1) was an officer or employee of our company, (2) was formerly an officer of our company, or (3) had any relationships requiring disclosure by us under the rules of the SEC with respect to certain relationships and related-party transactions. Furthermore, none of our executive officers currently serves, or served during the last fiscal year, as a member of the board of directors or compensation committee of any entity that has one or more executive officers serving on our board of directors or compensation committee.

Nominating and Corporate Governance Committee

The nominating and corporate governance committee of our board oversees the succession planning of our board, including the succession planning of our board leadership. The nominating and corporate governance committee identifies individuals qualified to become members of our board of directors, recommends candidates to fill vacancies and newly-created positions on our board of directors, recommends director nominees for election by stockholders at the annual meetings of stockholders and develops and recommends to our board of directors our corporate governance guidelines.

We believe that the nominating and corporate governance committee considers an appropriate range of criteria in assessing candidates for a position on the board of directors. Our corporate governance guidelines require that the criteria utilized by the corporate governance committee in assessing such candidates include factors such as judgment, diversity, integrity, experience with businesses and other organizations of comparable size, the interplay of a candidate's experience with the experience of other members of the board of directors and anything else that may bear upon the extent to which a candidate would be a desirable addition to our board of directors and any committees of our board of directors. The policies relating to the recommendation of director candidates adopted by the nominating and corporate governance committee are designed to ensure flexibility with respect to the process of evaluating candidates and do not establish specific minimum qualifications that an individual must meet to become a member of our board of directors. The nominating and corporate governance committee believes that our company is best served when it can draw from a variety of experiences and backgrounds provided by members of our board of directors. However, the nominating and corporate governance committee also believes that our company is best served when the members of the board of directors:

The nominating and corporate governance committee also assists management in the succession planning of our executive officers, including our CEO. At least annually, the nominating and corporate governance committee reports to the full board on succession planning, including the contingencies in case the CEO and Chairman of the Board or Lead Independent Directors retires, resigns or is incapacitated.

Other duties and responsibilities of the nominating and corporate governance committee include:

The nominating and corporate governance committee has adopted policies and procedures by which our stockholders may submit director candidates to the nominating and corporate governance committee for consideration. If the nominating and corporate governance committee receives, by a date not less than 120, nor more than 150, calendar days before the anniversary of the date that the proxy statement was mailed to stockholders in connection with our previous year's annual meeting, a recommendation for a director nominee from a stockholder or group of stockholders that beneficially owned more than 5% of our outstanding common stock for at least one year as of the date of the recommendation, then the director

candidate will be considered and evaluated by the nominating and corporate governance committee for the annual meeting immediately succeeding the date that proper written notice was timely delivered to and received by the nominating and corporate governance committee. When the date of our annual meeting of stockholders changes by more than 30 calendar days from the previous year's annual meeting, the written notice of the recommendation for the director candidate will be considered timely if, and only if, it is received by the nominating and corporate governance committee no later than the close of business on the tenth calendar day following the first day on which notice of the date of the upcoming annual meeting is publicly disclosed by us.

Written notice from an eligible stockholder or group of eligible stockholders to the nominating and corporate governance committee recommending a director candidate must contain or be accompanied by:

The notice must be signed by each stockholder submitting the proposal and the director candidate. The notice must be sent to the following address by registered or certified mail: Kaiser Aluminum Corporation, Attn: Corporate Secretary (Nominating and Corporate Governance Committee), 1550 West McEwen Drive, Suite 500, Franklin, Tennessee 37067.

The nominating and corporate governance committee charter requires that all members of the nominating and corporate governance committee satisfy, and all members of the nominating and corporate governance committee during 2024 satisfied, the general independence criteria. In addition, the members of the nominating and corporate governance committee must include at least one of the directors nominated by the USW.

Sustainability Committee

The sustainability committee of our board of directors assists the board of directors in discharging its responsibilities relating to our corporate values, talent development and hiring initiatives. We consider our corporate values, talent development and hiring priorities throughout the Company and recognize that, over the long term, our commitment to each and the sustainability of our business and creation of long-term value for our stakeholders provide competitive advantages.

The sustainability committee reviews and evaluates the development and training of our employees, the diversity of our management and workforce, and our hiring initiatives. In addition, the sustainability committee provides more focused oversight of the Company’s strategic sustainability activities and initiatives, consistent with our corporate values, including (1) the review, on a periodic basis, of our corporate values and key initiatives supporting our corporate values, (2) the oversight

of the preparation and publication of our annual sustainability reports, (3) the oversight of our key sustainability strategies and initiatives, including (a) internal and external metrics and goals with respect to greenhouse gas emissions and other related sustainability metrics, (b) our sustainability performance, (c) our sustainability-related risks and opportunities, including climate-related risks and opportunities, and (d) emerging trends and investor expectations regarding sustainability topics, and (4) the review of our leadership and development programs and training.

Board and Committee Meetings and Consents in 2024

During 2024, our board of directors held four meetings and acted by unanimous written consent six times. In addition to meetings of our board of directors, directors attended meetings of committees of our board of directors. Each director attended at least 75% of the aggregate number of meetings that our board of directors held during the period the director was on our board of directors in 2024 and each committee on which the director served held during the period the director served on such committee in 2024.

Annual Meetings of Stockholders

Members of our board of directors are expected to make reasonable efforts to attend our annual meetings of stockholders. All of our directors then serving attended our 2024 annual meeting of stockholders.

Annual Performance Reviews

We conduct robust annual board, committee and director assessments. Under our corporate governance guidelines, our board of directors is required to conduct an annual self-evaluation to determine whether our board of directors, its committees and directors are functioning effectively. As part of the annual evaluation, the board of directors also assesses whether the board of directors and individual directors possess the strategic board skills, experience and attributes identified by the board of directors as priorities as it considers our strategy and board succession planning. At least once every three years, the board of directors utilize a third party evaluator to facilitate the annual evaluation and assessment, including interviews with individual directors. The results from the interviews are summarized and reviewed with the nominating and corporate governance committee and the board of directors. The Lead Independent Director and Chairman also meet with each director individually to discuss board and committee performance.

The charter for each committee of our board of directors also requires each committee to annually evaluate its performance. The nominating and corporate governance committee reviews the annual evaluation process and modifies the process as it deems appropriate. In addition, we coordinate with the USW not less than annually to discuss (i) our most recent assessment of strategic board skills, experience, attributes of all directors, (ii) desired strategic board skills, experience, attributes and priorities in the context of anticipated vacancies and upcoming elections and (iii) each board member nominated by the USW and contemplated future USW nominees in light of these considerations.

Stockholder Engagement

We value stockholder feedback and insights and believe that accountability to stockholders is an essential component of good governance. We engage in ongoing, proactive discussions of a variety of topics with significant stockholders throughout the year. Those discussions may include our CEO and Chairman of the Board, Lead Independent Director and/or other members of senior management when requested by our stockholders. In addition to providing our perspective and seeking feedback on topics specific to our company, we invite discussion on any other topics or trends stockholders may wish to discuss with us. The feedback provided by stockholders is reported to the full board of directors. Our board of directors reviews the feedback and determines whether additional discussion and actions by the full board or any board committees are necessary. In 2024, in addition to interactions regarding our financial performance, we engaged with stockholders representing greater than 50% of our outstanding shares on matters relating to our business strategy and performance; operations, including metal sourcing and recycled content strategies; capital allocation; long-term outlook; board structure; board and executive leadership succession planning; governance; executive compensation; and other sustainability matters, including the Warrick power separation project. This information is also reviewed by members of our senior management and the full board of directors.

Sustainable Value Creation

Our corporate values define how we pursue sustainable business value and serve as the foundation for our culture and our strategic ambitions. We manage our business for long-term value creation in a manner that is economically, environmentally and socially responsible. Below are highlights of our accomplishments in 2024 and their alignment with our five corporate values:

2025 and Beyond

We recognize that long-term excellence requires sustainable business practices and strong governance. Accordingly, we intend to continue our efforts to advance our sustainability and governance as a company, including our efforts to:

Stock Ownership Guidelines and Securities Trading Policy

Our stock ownership guidelines require our non-employee directors to own company stock equal to six times their annual base retainer within five years of becoming a member of our board of directors. For purposes of measuring compliance with our stock ownership guidelines, restricted stock is valued at the closing price of our common stock on the grant date and all other shares of common stock purchased or acquired are valued at the purchase price of such shares. Except for Messrs. Arnold, Grimley and Williams and Ms. Glas, who joined the board in the past few years, and Ms. Martin, each of our non-employee directors satisfies the applicable stock ownership requirements under the stock ownership guidelines. Messrs. Arnold, Grimley and Williams and Ms. Glas are on track to meet our stock ownership requirements. Ms. Martin, who previously met the applicable stock ownership requirements but is no longer deemed the beneficial owner of certain shares gifted to a family trust, is currently retaining at least 75% of net shares resulting from equity compensation awards until she comes into compliance with the applicable stock ownership requirement. Our stock ownership guidelines also apply to senior management. For additional information regarding our stock ownership guidelines, see "Executive Compensation - Stock Ownership Guidelines."

We have adopted a securities trading policy that governs the purchase, sale and other dispositions of our securities by directors, officers and other employees, including our named executive officers, in order to promote compliance with insider trading laws, rules and regulations and Nasdaq listing standards. Among other limitations, our securities trading policy prohibits our directors, employees, including our named executive officers, and independent directors, and members of their immediate families, from purchasing financial instruments to hedge or offset, or otherwise engaging in transactions designed to hedge or offset, decreases in the market value of our equity securities, whether granted as part of compensation to, or otherwise held directly or indirectly by, such director or employee. Prohibited transactions include short sales, options, puts, calls and derivative instruments such as swaps, forwards, collars and futures. Our securities trading policy also prohibits our directors, employees, including our named executive officers, and independent contractors, and members of their immediate families, from buying our securities on margin (other than purchases where the related margin borrowings are effected solely for the purpose of paying the option exercise price upon the exercise of an option to purchase shares from the Company, which are typically referred to as “cashless exercises”), holding our securities in a margin account, pledging our securities as collateral for a loan or any other obligations or entering into share lending programs.

Risks Arising from Compensation Policies and Practices

Our compensation policies and practices, discussed more fully below, are designed to create and maintain alignment between our employees and stockholders by rewarding employees, including our senior management, for achieving strategic goals that successfully drive our operations and enhance stockholder value and to preclude the taking of unreasonable risks through the use of incentive compensation that rewards decisions that result in strong performance in both the short-and

long-term. We do not believe that our compensation policies and practices encourage decisions or actions which are likely to have a material adverse effect on our company. Our determination is based on, among other factors, the following:

Stockholder Communications with the Board of Directors

Our stockholders may communicate with our board of directors as a group or with the chair of the executive committee, audit committee, compensation committee or nominating and corporate governance committee by sending an email to boardofdirectors@kaiseraluminum.com, execchair@kaiseraluminum.com, auditchair@kaiseraluminum.com, compchair@kaiseraluminum.com, or nominatingchair@kaiseraluminum.com, respectively, or by writing to the group or person at Kaiser Aluminum Corporation, Attn: Corporate Secretary (Board of Directors), 1550 West McEwen Drive, Suite 500, Franklin, Tennessee 37067. Communications that are intended specifically for any other group of directors or for any individual director, such as the independent directors as a group or the Lead Independent Director, should be sent to the attention of our corporate secretary at the address above or via email to corpsecretary@kaiseraluminum.com and should clearly state the individual director or group of directors that is the intended recipient of the communication.

Our corporate secretary will review each communication and determine whether or not the communication is appropriate for delivery. Communications that, in the judgment of our corporate secretary, are clearly of a marketing nature, that advocate that our company engage in illegal activity, that do not reasonably relate to our company or our business or that are similarly inappropriate will not be furnished to the intended recipient. If, in the judgment of the corporate secretary, any communication pertains to an accounting matter, it will be forwarded to our compliance officer.

Communications that, in the judgment of our corporate secretary, are appropriate for delivery will, unless requiring immediate attention, be assembled and delivered to the intended recipients on a periodic basis, generally at or in advance of each regularly scheduled meeting of our board of directors. Any communication that, in the judgment of our corporate secretary, requires immediate attention will be promptly delivered. In no case will the corporate secretary provide anyone but a member of our board of directors with access to any such communication, except as noted above with respect to communications pertaining to accounting matters.

EXECUTIVE OFFICERS

The following table sets forth the names and ages of each of our executive officers and the positions they held as of April 17, 2025, the record date.

Set forth below are brief descriptions of the business experience of each of our executive officers.

Keith A. Harvey has served as our President and Chief Executive Officer and as a director since July 2020 and as Chairman of our Board since January 2025. He previously served as President and Chief Operating Officer from December 2015 to July 2020, Executive Vice President - Fabricated Products from June 2014 to December 2015, Senior Vice President - Sales and Marketing, Aerospace and General Engineering from June 2012 to June 2014, Vice President - Sales and Marketing, Aerospace and General Engineering from 2000 to June 2012 and as our Vice President - Sales and Marketing of Extruded Products from 1996 to 2000. Mr. Harvey joined Kaiser in 1981 as an industrial engineer at the Company’s former rolling mill in West Virginia. He subsequently held positions of increasing responsibility in engineering and sales at several Kaiser locations and was named a Vice President in 1994. Mr. Harvey holds a Bachelor of Science degree in Industrial Engineering from West Virginia University.

Neal E. West has served as our Executive Vice President and Chief Financial Officer since March 2021 and as Senior Vice President and Chief Financial Officer from February 2019 to March 2021. Mr. West joined our company in June 2008 as Vice President and Chief Accounting Officer. Prior to joining Kaiser, Mr. West served as the Principal Accounting Officer of Gateway, Inc. from June 2005 to May 2008. Mr. West was also the Vice President and Corporate Controller of Gateway, Inc. from April 2005 to May 2008. Prior to joining Gateway, Inc., Mr. West was the Vice President and Controller for APL Logistics, Ltd. from April 2000 to April 2005. In addition, Mr. West has held a number of finance, service and support positions at APL Ltd. Mr. West also previously worked for Standard Pacific and West-Tronics, Inc. as Division Controller and Financial Manager. Mr. West is a Certified Public Accountant and a Certified Management Accountant and holds a Master of Science degree in information systems from Roosevelt University and a Bachelor of Science degree in accounting and business administration from Illinois State University.

John M. Donnan has served as our Executive Vice President, Chief Administrative Officer and General Counsel since March 2021. Mr. Donnan is responsible for our company’s corporate legal, compliance, internal audit, and human resources functions. He previously served as our Executive Vice President – Legal, Compliance and Human Resources from June 2012 to March 2021, our Senior Vice President, Secretary and General Counsel from December 2007 to June 2012 and as our Vice President, Secretary and General Counsel from January 2005 to December 2007. Mr. Donnan joined the legal staff of Kaiser in 1993 and was named Deputy General Counsel of Kaiser in 2000. Prior to joining Kaiser, Mr. Donnan was an associate in the Houston, Texas office of the law firm of Chamberlain, Hrdlicka, White, Williams & Martin. He holds a Juris Doctorate degree from the University of Arkansas School of Law and Bachelor of Business Administration degrees in finance and accounting from Texas Tech University. He is a member of the Texas and California bars.

Vijai Narayan has served as our Vice President, Corporate Controller and Chief Accounting Officer since April 2024. Mr. Narayan joined our company in November 2022 as Vice President - Finance and served as Vice President and Chief Accounting Officer from June 2023 to April 2024. Prior to joining Kaiser, Mr. Narayan was Vice President Finance and Controller of eviCore Healthcare, a medical benefits management company and subsidiary of Cigna Corporation from April 2020 to November 2022. Previously, Mr. Narayan was a Partner in the Financial Accounting Advisory Services practice of Ernst & Young LLP. Mr. Narayan holds a Bachelor of Commerce degree from the University of Mumbai and a Master of Accountancy and Master of Business Administration from Bowling Green State University. He is also a Certified Public Accountant, licensed in the State of Tennessee.

Raymond D. Parkinson has served as our Senior Vice President - Advanced Engineering and Innovation since April 2024. He previously served as Senior Vice President - Advanced Engineering from January 2020 to April 2024 and Vice President - Advanced Engineering from 2001 to January 2020. Dr. Parkinson joined Kaiser in 1986 as technical director for extruded products and has more than 30 years of experience in sales, operations, quality control, engineering and research and development in diverse manufacturing environments. Dr. Parkinson has a Ph.D. in metallurgy, as well as Bachelor’s and Master’s degrees in Engineering, from Imperial College in the United Kingdom and a Master of Business Administration from St. Mary’s College. Dr. Parkinson is also a Fellow of the Institute of Materials, Minerals and Mining.

Blain A. Tiffany has served as Executive Vice President – Sales and Marketing since April 2022. Mr. Tiffany previously served as Senior Vice President – Sales and Marketing from January 2020 to April 2022 and as Vice President – Sales & Marketing, High Strength and General Engineering Products from July 2014 to December 2020. Mr. Tiffany joined Kaiser in 2013 as Vice President - Marketing, Hard Alloy Extrusions, Pipe and Tube. Prior to joining Kaiser, Mr. Tiffany held several senior management positions during his 34 years in metals distribution, most recently with A.M. Castle & Co. where during his 13 years with the company he served as President of the Steel Plate division, President of the Aerospace division and President of the Industrial division. He holds a Bachelor of Science degree in Business Administration from Almeda College and completed the Strategic Metals Management Program at the Olin Business School Washington University in St. Louis, Missouri.

Jason D. Walsh has served as our Executive Vice President – Manufacturing since April 2022. Mr. Walsh previously served as Senior Vice President – Manufacturing from August 2020 to April 2022 , as Senior Vice President – Flat Rolled Products from June 2018 to August 2020, as Vice President and General Manager – Automotive and Soft Alloy from January 2018 to June 2018, as Vice President and General Manager – Automotive from February 2017 to December 2017, and as Vice President – Financial, Planning and Analysis from April 2012 to January 2017. Mr. Walsh joined Kaiser in 2006 as Manager, Financial Planning & Analysis and served as Group Controller, Common Alloy Products and Director, Financial Planning & Analysis. Prior to joining Kaiser, he held positions of increasing responsibility in manufacturing operations with Caterpillar Inc. He holds a Master of Business Administration degree in Finance from the University of Chicago and a Bachelor of Science degree in Mechanical Engineering from the University of Illinois at Urbana-Champaign.

EXECUTIVE COMPENSATION

Compensation Committee Report

The compensation committee has reviewed and discussed with management the CD&A section included below. Based on its review and discussions with management, the compensation committee recommended to the board of directors that the Compensation Discussion and Analysis be included in this Proxy Statement and incorporated by reference into our Annual Report on Form 10-K filed on February 20, 2025.

This report is submitted by the members of the compensation committee of the board of directors:

Compensation Committee

Donald J. Stebbins (Chair)

Richard P. Grimley

Lauralee E. Martin

Brett E. Wilcox

Kevin W. Williams

Compensation Discussion and Analysis

Introduction

This section provides:

2024 Performance Highlights(1), (2)

In 2024, we delivered solid performance despite a highly complex and dynamic market environment. We continued to expand our margin and were nearing completion of significant growth investments at year end. We remain well positioned for sustainable, long-term growth.

The table below highlights our 2024 financial performance:

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Balanced Capital Allocation Priorities

Our capital allocation strategy focuses on organic investment, external growth and returning cash to stockholders through dividends and share repurchases.

1 Excess cash is liquidity beyond the minimum required in contingency planning for an economic downturn.

Organic Investment Strategy

Inorganic Investment Strategy

We use a strategic filter to review all potential acquisitions. We will not engage in an acquisition unless it has a strategic rationale that passes the strategic filter.

Value Returned to Stockholders

We also expect to continue to pay regular dividends. Since 2007, we have returned approximately $1 billion to stockholders through quarterly dividends and share repurchases.

1 Return to shareholders from January 1, 2007 through December 31, 2024.

Overview of the Compensation Committee

The compensation committee of our board of directors is comprised entirely of independent directors. By design, members of the compensation committee also serve on other board committees, including the executive committee, the audit committee, the nominating and corporate governance committee and the sustainability committee. We believe this structure helps coordinate the efforts of the respective committees. The compensation committee's primary duties and

responsibilities are to establish and implement our compensation policies and programs for senior management. While the nominating and corporate governance committee has the responsibility to evaluate the overall performance of our CEO, the compensation committee coordinates with and assists the nominating and corporate governance committee in that evaluation.

The compensation committee has the authority under its charter to engage the services of outside advisors, experts and others to assist it. Pursuant to that authority, the compensation committee engaged Meridian to advise it on all matters related to compensation of our CEO and other members of senior management, including the other named executive officers.

The compensation committee meets formally and informally throughout the year. Informal meetings frequently occur when our directors are together for meetings of our full board of directors and virtually at the request of one or more committee members. Our CEO, other members of our management and outside advisors may be invited to attend all or a portion of a compensation committee meeting depending on the nature of the agenda items; however, neither our CEO nor any other member of management votes on items before the compensation committee.

The compensation committee works with our senior management and Meridian to determine the agenda for its formal meetings and to prepare meeting materials. The compensation committee and our board of directors also solicit the views of our CEO on compensation matters, including, among others:

Objectives of our Compensation Structure

Our compensation structure was developed to achieve the following objectives, which we believe are critical for enhancing stockholder value and to our long-term success and sustainability:

Design of our 2024 Compensation Program

Our 2024 compensation program for our senior management, including our named executive officers, was designed to reinforce performance and accountability at the corporate, operational and individual levels through the use of:

As previously discussed, effective January 1, 2025, we elected to change our method of accounting for certain inventory from the LIFO method to the WAC method to improve the comparability of our operational results between periods. This accounting change was not retrospectively applied to the financial results with respect to Adjusted EBITDA and Adjusted

EBITDA margin for purposes of our short-term annual cash incentive awards and our 2022-2024 LTI Plan. Therefore the reconciliation of Adjusted EBITDA on Appendix A of this Proxy Statement is not applicable.

In addition to focusing on "pay for performance," our 2024 compensation program:

Periodically, but not less than annually, each element of compensation is reviewed and considered by the compensation committee and our board of directors both individually and collectively with the other elements of compensation to ensure that each element is consistent with the objectives of both our comprehensive compensation structure and that particular element of compensation. The compensation committee and our board of directors share suggestions or concerns identified in the course of that review with senior management and Meridian, who address the suggestions or concerns in a manner that is satisfactory to the compensation committee and our board of directors. This process occurs over a series of meetings of the compensation committee and our board of directors and executive sessions of the independent directors without members of management present.

In designing the overall compensation program and each individual element of compensation for senior management, including our named executive officers, the compensation committee considers the following factors, among others:

The compensation committee generally uses tally and other summary sheets that provide a summary of the compensation history of our CEO and those members of our senior management reporting to our CEO. These tally and information sheets include a historical summary of base salary, annual bonus and equity awards.

In reviewing and deliberating our 2024 compensation program, the compensation committee considered, among other things:

The review included discussions with Meridian and management regarding existing and contemplated market practices, as well as the structure and objectives of each component of our compensation program.

The compensation committee also reviews the compensation and benefit practices, as well as levels of pay, of a compensation peer group of companies. Working with Meridian, the compensation committee selects for inclusion in our compensation peer group companies that are determined to:

The compensation committee, working with Meridian, reviews, evaluates and updates our compensation peer group, which includes companies in both similar and different industries, at least annually. For 2024, the compensation committee approved a 23-company peer group. Compared to the peer group used for 2023, Arconic Corporation and Resolute Forest Products Inc. were removed, as they were taken private and acquired, respectively, and, as a result, would no longer publish compensation information. As of November 2023, the new custom peer group had (1) market capitalization ranging from approximately $240 million to approximately $21.2 billion and a median market capitalization of approximately $4.4 billion, and (2) trailing 12 months revenues ranging from $2.0 billion to approximately $8.8 billion and median revenue of approximately $3.6 billion. Our market capitalization and revenue, both as of December 31, 2023, were $1.1 billion and $3.1 billion, respectively.

Due to the differences in size among the companies in our peer group, Meridian uses a regression analysis to adjust survey data results based on our revenue as compared to the revenue of other companies in our peer group. Importantly, the compensation committee recognizes that we compete for talent with companies much larger than us. These larger companies, including Arconic Corporation, Constellium SE, Novelis Inc. and Norsk Hydro ASA, aggressively recruit talent in

critical functions. As a result, to attract and retain talent, the compensation committee may from time to time determine that it is in the best interests of our company and our stockholders to provide compensation packages that deviate from targeted pay levels. For 2024, in addition to data obtained from publicly disclosed proxy statements, Meridian also provided data obtained from Equilar Executive Compensation Survey. We did not select the constituent companies comprising this survey group, however, and the component companies’ identities were not a material factor in the applicable compensation analysis.

For 2025, the compensation committee approved the same peer group as 2024, except for the removal of Howmet Aerospace, Inc. due to its outpaced growth in 2024 compared to the other peers.

Principal Elements of 2024 Compensation

The table below summarizes the key elements of our named executive officers' compensation in 2024: