The proxy statement and annual report are available on the Internet at www.proxyvote.com.

The following information applicable to the Annual Meeting may be found in the proxy statement and the Notice or proxy card, as applicable:

If you were a stockholder of record as of the close of business on March 6, 2023,2024, you are entitled to vote at the Annual Meeting and at any adjournment thereof.

Instead of mailing a printed copy of our proxy materials, including our 20222023 Annual Report, to each stockholder of record, we are providing access to these materials via the Internet. This reduces the amount of paper necessary to produce these materials, as well as the costs associated with mailing these materials to all stockholders.

If you previously elected to receive a printed copy of the materials, we have enclosed a copy of our 20222023 Annual Report to Stockholders with this Notice and Proxy Statement.

Most stockholders can vote by proxy in three ways:

If you are a stockholder of record, you can vote your shares by voting by Internet, telephone, mailing in your proxy or during the Annual Meeting. You may give us your proxy by following the instructions included in the Notice or, if you received a printed version of these proxy materials, in the enclosed proxy card. If you want to vote by mail but have not received a printed version of these proxy materials, you may request a full packet of proxy materials through the instructions in the Notice. If you vote using either telephone or the Internet, you will save us mailing expense.

By giving us your proxy, you will be directing us how to vote your shares at the Annual Meeting. Even if you plan to attend the Annual Meeting, we urge you to vote now by giving us your proxy. This will ensure that your vote is represented at the Annual Meeting. If you do attend the Annual Meeting, you can change your vote at that time, if you then desire to do so.

If you are the beneficial owner of shares held in street name, the methods by which you can access the proxy materials and give the voting instructions to the broker or nominee may vary. Accordingly, beneficial owners should follow the instructions provided by their brokers or nominees to vote by Internet, telephone or mail. If you want to vote by mail but have not received a printed version of these proxy materials, you may request a full packet of proxy materials as instructed by the Notice. If you want to vote your shares during the Annual Meeting, you must obtain a valid proxy from your broker or nominee. You should contact your broker or nominee or refer to the instructions provided by your broker or nominee for further information. Additionally, the availability of Internet or telephone voting depends on the voting process used by the broker or nominee that holds your shares.

You may receive more than one Notice or proxy statement and proxy card or voting instruction form if your shares are held through more than one account (e.g., through different brokers or nominees). Each proxy card or voting instruction form only covers those shares held in the applicable account. If you hold shares in more than one account, you will have to provide voting instructions for all of your accounts to vote all your shares.

(by Internet, telephone or mail) that you first used to vote your shares. This will help the inspector of election for the Annual Meeting verify your latest vote.

For beneficial owners of shares held in street name, you should follow the instructions in the information provided by your broker or nominee to change your vote or revoke your proxy. If you want to change your vote as to shares held in street name by voting during the Annual Meeting, you must obtain a valid proxy from the broker or nominee that holds those shares for you.

The Annual Meeting will be held only if a quorum exists. The presence at the Annual Meeting, in person or by proxy, of holders of a majority of our outstanding shares of common stock as of the record date will constitute a quorum. If you attend the Annual Meeting or vote your shares by Internet, telephone or mail, your shares will be counted toward a quorum, even if you abstain from voting on a particular matter. Shares held by brokers and other nominees as to which they have not received voting instructions from the beneficial owners and lack the discretionary authority to vote on a particular matter are called “broker non-votes” and will count for quorum purposes.

We are asking you to vote on the following proposals:

For the proposal on the election of directors, a director nominee will be elected to the Board of Directors if the numbers of votes cast "FOR" the nominee exceeds the number of votes cast "AGAINST" at the Annual Meeting. You may vote “FOR” or "AGAINST" each director nominee or abstain from voting for one or more nominees. Abstentions and broker non-votes with respect to the election of directors will have no effect on the outcome and do not count as votes cast. Under our Bylaws, in the event of a contested election, the director nominees will be elected by the affirmative vote of a plurality of the votes cast by the shares of our common stock entitled to vote in the election of directors at the Annual Meeting.

For the advisory vote on executive compensation proposal, you may vote “FOR” or “AGAINST” or abstain from voting. This proposal requires the affirmative vote of a majority of the shares of our common stock present in person or represented by proxy at the Annual Meeting and entitled to vote on the matter in order to be adopted. Abstentions are counted for purposes of determining a quorum and are considered present and entitled to vote on this proposal. As a result, abstentions have the effect of an “AGAINST” vote. Broker non-votes will not be considered as entitled to vote on this proposal, even though they are considered present for purposes of determining a quorum and may be entitled to vote on other matters. As a result, broker non-votes will not have any effect on this proposal.

For the proposal to ratify the appointment of Deloitte as our independent registered public accounting firm, you may vote “FOR” or “AGAINST” or abstain from voting. This proposal requires the affirmative vote of a majority of the votes cast on the matter. Abstentions will not be considered as cast and, as a result, will not have any effect on the proposal.

For stockholders of record, all shares represented by the proxies will be voted at the Annual Meeting in accordance with instructions given by the stockholders. Where a stockholder returns their proxy and no instructions are given with respect to a given matter, the shares will be voted: (1) “FOR” the election of directors; (2) “FOR” the approval of the compensation of our named executive officers on an advisory basis; (3) "1 YEAR" on the advisory vote on the frequency of the advisory vote on the compensation of our named executive officers; (4) “FOR” the ratification of the appointment of Deloitte as our independent registered public accounting firm; and (5)(4) in the discretion of the proxy holders upon such other business as may properly come before the Annual Meeting. If you are a stockholder of record and you do not return your proxy, no votes will be cast on your behalf on any of the items of business at the Annual Meeting.

For beneficial owners of shares held in street name, the brokers or nominees holding shares for beneficial owners must vote those shares as instructed. Absent instructions from you, brokers, banks and nominees may vote your shares only as they decide as to matters for which they have discretionary authority under the applicable New York Stock Exchange rules. A broker, bank or nominee does not have discretion to vote on the election of directors or approval of the compensation of our named executive officers. If you do not instruct your broker, bank or nominee how to vote on those matters, no votes will be cast on your behalf on the election of directors or the advisory vote on compensation of our named executive officers or the advisory vote on the frequency of the advisory vote on executive compensation.officers. Your broker will be entitled to vote your shares in its discretion, absent instructions from you, on the ratification of the appointment of Deloitte as our independent registered public accounting firm. Any shares of our common stock held in the Thrift Plan for Employees of BWXT and Participating Subsidiary and Affiliated Companies (our "Thrift Plan”) that are not voted or for which Vanguard, as trustee of the Thrift Plan, does not receive timely voting instructions, will be voted in the same proportion as the shares for which Vanguard receives timely voting instructions from other participants in the Thrift Plan.

We are not aware of any other matters that may be presented or acted on at the Annual Meeting. If you vote by signing and returning the enclosed proxy card or using the Internet or telephone voting procedures, the individuals named as proxies on the card may vote your shares, in their discretion, on any other matter requiring a stockholder vote that comes before the Annual Meeting.

All voted proxies and ballots will be handled to protect your voting privacy as a stockholder. Your vote will not be disclosed except:

Based on these independence standards, our Board has determined that the following eightnine directors are independent and meet our categorical standards:

In determining the independence of the directors, our Board considered ordinary course transactions between us and other entities with which the directors are associated. None were determined to constitute a material relationship with us.

The Board also determined that Mr. Geveden, who serves as an executive officer of the Company, is not an independent director. Accordingly, we currently have a supermajority of independent directors (eight(nine of nine,ten, or 89%90%) in compliance with our Corporate Governance Principles which require a majority of independent directors.

The mission of our Board is to promote the best interests of the Company’s stockholders through oversight of the management of the Company’s business and affairs. The Board believes that its corporate governance policies and practices provide independent oversight and accountability of management. The Company’s Corporate Governance Principles and Committee Charters provide for a number of processes and practices, including the 10-year12-year director tenure limit; appointment of a Lead Independent Director in appropriate circumstances; executive sessions of the independent directors without management at each regular Board meeting; a majority of independent directors; and an Audit and Finance Committee, Compensation Committee and Governance Committee, each comprised exclusively of independent directors.

BWXT does not have a policy requiring that the positions of Chair and Chief Executive Officer be separate or be occupied by the same individual. Our Board believes that this question is properly addressed as part of succession planning and that it is appropriate to make a determination on these matters when it elects a new Chief Executive Officer, appoints a new Chair or at other times. In anticipation of the retirement of Mr. Fees as our Non-Executive Chairman at the 2022 Annual Meeting, the Board undertook its regular succession planning process and elected JanMs. Bertsch asis currently the Independent Board Chair, and eliminated theso there is no lead independent director role at thatthis time.

Our Bylaws provideBoard has a 12-year director tenure policy that provides that (1) a person shall not be nominated for election or reelection to our Board if such person will have served as a director for 1012 years prior to the date of election or re-electionreelection (as measured from July 1, 2015, the effective date of the Bylaw amendment, July 1, 2015)Spin-off) and (2) any director who attains 1012 years of service during his or her term shall be deemedis expected to have resigned and retiredresign at the first annual meeting following his or her attainmentsuch attainment. As part of 10 yearsits annual governance review process, the Board reviewed the 10-year director tenure limit which was in place until August 2023, benchmarked the director tenure limit against peer companies and elected to move to a 12-year limit (as measured from July 1, 2015), which the Board determined was in the best interests of service as a director.the Company and stockholders.

Our Bylaws provide that, in an election of directors where the number of director nominees does not exceed the number of directors to be elected (an "Uncontested Election"), each director nominee must receive the majority of the votes cast with respect to that director. Each director nominee has submitted an irrevocable resignation contingent on (i) the receipt of a majority of the votes cast in an Uncontested Election and (ii) acceptance of such resignation by the Board. If a director nominee were not receive a majority vote, the Governance Committee would make a recommendation to the Board on whether to accept or reject the resignation or take other action. Any action taken by the Board would be publicly disclosed within 90 days of certification of the election results.

Our Board met four times during 2022.2023. Each director attended 100%at least 92% of the meetings of the Board and of the committees on which they served during the time they served on the Board in 2022.2023. In addition, as reflected in our Corporate Governance Principles, we have adopted a policy that each member of our Board must make reasonable efforts to attend our Annual Meeting. All of our current directors who were directors at the time of the meeting attended the 20222023 Annual Meeting of Stockholders.

During 2022,2023, non-employee director compensation generally consisted of cash and equity. The compensation of our non-employee directors under our current non-employee director compensation program is described in more detail below.

The amounts reported in the “Stock Awards” column represent the grant date fair value computed in accordance with FASB ASC Topic 718. Grant date fair values are determined using the closing price of our common stock on the date of grant. Each non-employee director, except for Ms. Piasecki who joined the Board on January 1, 2024, received an annual equity grant of 2,5612,391 restricted stock units on May 3, 20222023 with a grant date fair value of $129,971$154,937 based on the closing price of our common stock of $50.75$64.80 per share. There were no unvested stock awards or unexercised option awards (whether or not exercisable) held by the non-employee directors as of December 31, 2022.2023. No option awards were granted to directors in 2022.2023.

Under our Incentive Plan, directors may elect to defer payment of all or a portion of their stock awards. Ms. Bertsch and Messrs. Burbach, Jaska, Krieg, Melvin, Nardelli Melvin and Richardson each elected to defer 100% of their 20222023 stock awards. No other directors made a deferral election with respect to their stock awards in 2022.2023. Amounts reported in the Director Compensation Table include amounts deferred in 2022.2023.

This CD&A is divided into four sections:

Our executive compensation plan for 20222023 is consistent with our historical pay-for-performance approach that incorporates feedback from our stockholder outreach efforts and metrics designed to drive the performance of BWXT. We engage directly with our stockholders on executive compensation, governance, environmental, social and other topics. See "Stockholder Engagement" above for more information on our engagement process.

Based on feedback from our stockholders, our Compensation Committee continued with a market-based, pay-for-performance structure for our executive compensation program and also enhanced the performance-based components of the program. In addition, the Compensation Committee incorporated a double-trigger vesting requirement for equity awards in the event of a change in control in our 2020 Omnibus Incentive Plan ("2020 Plan"), approved by stockholders at our 2020 Annual Meeting. We have received feedback from stockholders regarding the use of ESG metrics in our incentive plans. The Compensation Committee has included safety metrics in our annual incentive plan each year since our spin-off in 2015 and will evaluate other possible ESG metrics.

Following a comprehensive review of our executive compensation program with Exequity, our executive compensation consultant, we made the following design changes to the 20222023 executive compensation program: (i) adding total shareholder return ("TSR")decreased the weighting of our operating income metric in our short-term incentive plan from 75% to 70%; (ii) increased the weighting of our operating cash flow metric in our short-term incentive plan from 15% to 20%; (iii) changed the threshold and maximum performance parameters within our short-term incentive plan from 80% and 120%, respectively, to 85% and 115%, respectively; and (iv) introduced non-qualified stock options as a metric forcomponent of our long-term incentive plan,equity grant program for our Named Executives and (ii) replacing adjusted earnings per share with adjusted earnings before interest, tax, depreciation and amortization ("EBITDA") as a metric in our long-term incentive plan.certain other management employees. The following are some of the key design attributes and components of BWXT's 20222023 incentive program.

We seek to provide reasonable and competitive compensation to executives through programs structured to:

We also subscribe to a “pay-for-performance” philosophy when designing executive compensation. This means a substantial portion of an executive’s target compensation should be “at risk” and performance-based, where the value of one or more elements of compensation is tied to the achievement of pre-determined financial and/or other measures we consider important drivers in the creation of stockholder value. Our compensation philosophy requires that a substantial portion of total compensation be designed to appropriately balance short- and long-term performance incentives to align our Named Executives’ interests with those of our stockholders.

To support our compensation philosophy and objectives, our executive compensation program consists of base salary, annual incentives and long-term incentives, which we refer to as Total Direct Compensation. In addition to the elements of Total Direct Compensation, we also offer other benefits and practices consistent with the market. See “Section 3: Other Benefits and Practices” on the following pages of this CD&A for additional information on these benefits and practices.

The Compensation Committee does not set a specific target allocation among the elements of total direct compensation; however, long-term incentive compensation typically represents the largest single element of target total direct compensation, and performance-based compensation constitutes the substantial majority of a Named Executive’s target total direct compensation.

The following table and chart reflect the key elements and proportion of each Named Executive’s target total direct compensation for 2022,2023, the rationale for each element, and the financial performance metrics selected for our 20222023 annual incentive awards.