UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

(Rule 14a-101)

Proxy Statement Pursuant to Section 14(a) of the

Securities Exchange Act of 1934 (Amendment No. )

Check the appropriate box:

MERCER INTERNATIONAL INC.

(Name of Registrant as Specified In Its Charter)

N/A

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

Payment of Filing Fee (Check the appropriate box):

MERCER INTERNATIONAL INC.

NOTICE OF ANNUAL MEETING OF SHAREHOLDERS

The 2025 Annual Meeting (the "Annual Meeting") of shareholders ("Shareholders") of Mercer International Inc. (the "Company") will be held at Suite 1120, 700 West Pender Street, Vancouver, British Columbia, Canada on May 30, 2025 at 10:00 a.m. (Vancouver time) (doors open at 9:30 a.m. (Vancouver time)) for the following purposes:

For those who are not able to attend in person, the Company is offering a virtual Shareholder meeting in which Shareholders may listen to the Annual Meeting, submit questions and vote online at: www.meetnow.global/MZDKCKM.

Only Shareholders of record at the close of business on March 27, 2025 will be entitled to notice of, and to vote at, the Annual Meeting or any adjournment, postponement or rescheduling thereof.

YOUR VOTE IS VERY IMPORTANT. Whether or not you plan to attend our Annual Meeting in person or through the virtual meeting, we urge you to cast your vote and submit your proxy as promptly as possible by one of the methods below. Make sure to have your proxy card or voting instruction form in hand. You do not need to attend the Annual Meeting to vote if you submitted your proxy in advance of the Annual Meeting. A proxy may be revoked in the manner described in the accompanying proxy statement.

For further information on how to vote, please refer to the instructions on the accompanying proxy card and the accompanying proxy statement.

April 15, 2025

Important Notice Regarding the Availability of Proxy Materials for the Annual Meeting of Shareholders to be held on May 30, 2025: Our proxy statement and our 2024 Annual Report to Shareholders are available at www.mercerint.com/investors/reports-filings/. Additionally, you may access our proxy materials at www.proxyvote.com or www.investorvote.com/merc, a site that does not have "cookies" that identify visitors to the site.

PROXY STATEMENT

TABLE OF CONTENTS

Notice Regarding Forward-Looking Statements

This Proxy Statement includes forward-looking statements intended to qualify for the safe harbor from liability established by the Private Securities Litigation Reform Act of 1995. All statements contained in this Proxy Statement other than statements of historical fact, including statements relating to trends in or expectations relating to the expected effects of our initiatives, strategies and plans, as well as trends in or expectations regarding our financial results and long-term growth model and drivers, and regarding our business strategy and plans and our objectives for future operations, are forward-looking statements. Statements herein that describe our business, strategy, plans, goals, future capital spending levels and potential for growth, improved profit margins and cash generation are forward-looking statements. The words "can", "believe", "may", "will", "continue", "anticipate", "intend", "expect", "seek", and similar expressions are intended to identify forward-looking statements. We have based these forward-looking statements largely on our current expectations and projections about future events and trends. All such forward-looking statements are subject to certain risks and uncertainties that could cause actual results and amounts to differ materially from those in forward-looking statements. For a detailed discussion of the risks and uncertainties, see the "Risk Factors" discussion in Item 1A of our annual report for 2024 (the "2024 Annual Report") . New risks emerge from time to time. It is not possible for our management to predict all risks, nor can we assess the impact of all factors on our business or the extent to which any factor, or combination of factors, may cause actual results to differ materially from those contained in any forward-looking statements we make. In light of these risks, uncertainties, and assumptions, the future events and trends discussed in this Proxy Statement may not occur and actual results could differ materially and adversely from those anticipated or implied in the forward-looking statements. You should not rely upon forward-looking statements as predictions of future events. The events and circumstances reflected in the forward-looking statements may not be achieved or occur. Although we believe that the expectations reflected in the forward-looking statements are reasonable, we cannot guarantee future results. The forward-looking statements included in this Proxy Statement are made only as of the date of this Proxy Statement and we undertake no obligation to update the forward-looking statements to reflect subsequent events or circumstances.

Non-GAAP Financial Measures

This Proxy Statement contains "non-GAAP financial measures", that is, financial measures that either exclude or include amounts that are not excluded or included in the most directly comparable measure calculated and presented in accordance with generally accepted accounting principles in the United States ("GAAP"). Specifically, we make use of the non-GAAP financial measure "Operating EBITDA" which is not a measure of financial performance under GAAP and should not be considered in isolation or as a substitute for analysis of our results as reported under GAAP. Operating EBITDA is defined as operating income (loss) plus depreciation and amortization and long-lived asset impairment charges. We use Operating EBITDA as a benchmark measurement of our own operating results and as a benchmark relative to our competitors. We consider it to be a meaningful supplement to operating income (loss) as a performance measure primarily because depreciation expense and long-lived asset impairment charges are not actual cash costs, and depreciation expense varies widely from company to company in a manner that we consider largely independent of the underlying cost efficiency of our operating facilities. In addition, we believe Operating EBITDA is commonly used by securities analysts, investors and other interested parties to evaluate our financial performance.

Operating EBITDA is a non-GAAP financial measure at the consolidated level and is considered different from Operating EBITDA at the segment level, referred to as "Segment Operating EBITDA", which is our single measure of segment profit or loss presented in our financial statements under GAAP. For more information on Segment Operating EBITDA, refer to the segment information note within our consolidated financial statements in the 2024 Annual Report.

The following table provides a reconciliation of net loss to operating income (loss) and Operating EBITDA for the years indicated:

MERCER INTERNATIONAL INC.

Suite 1120, 700 West Pender Street, Vancouver, B.C., V6C 1G8, Canada

PROXY STATEMENT

GENERAL INFORMATION

This proxy statement ("Proxy Statement") is furnished in connection with the solicitation by management of Mercer International Inc. of proxies for use at the annual meeting of our shareholders ("Shareholders") to be held at Suite 1120, 700 West Pender Street, Vancouver, British Columbia, Canada at 10:00 a.m. (Vancouver time) on May 30, 2025 (the "Meeting"), or any adjournment, postponement or rescheduling thereof.

References to "we", "our", "us", the "Company" or "Mercer" in this Proxy Statement mean Mercer International Inc. and its subsidiaries unless the context clearly suggests otherwise. References to "fiscal year" means an annual period ended December 31. Information herein for 2024 generally refers to our 2024 fiscal year.

If a proxy (a "Proxy") is properly executed and received by us prior to the Meeting or any adjournment, postponement or rescheduling thereof, the shares of our common stock (the "Shares") represented by such Proxy will be voted in the manner directed. Please see the Proxy for voting instructions. In the absence of voting instructions, the Shares will be voted for the proposals set out in the accompanying Notice of Annual Meeting of Shareholders and as shown in the table below and in accordance with the best judgment of the named proxies on any other matter properly brought before the Meeting:

A Proxy may be revoked at any time prior to its use by filing a written notice of revocation of proxy or a later dated Proxy with our registrar and transfer agent at Mercer International Legal Proxy c/o Computershare, Inc., P.O. Box 43001, Providence, RI 02940-3001. A Proxy may also be revoked by submitting another Proxy with a later date over the Internet, by telephone, to our registrar and transfer agent or by voting in person at the Meeting. Attending the Meeting will not, in and of itself, constitute revocation of a Proxy.

The holders of one-third of the outstanding Shares entitled to vote at the Meeting, present in person or represented by Proxy, constitutes a quorum for the Meeting. Shares represented by Proxies that reflect abstentions or broker non-votes (i.e., Shares held by a broker/dealer or other nominee that are not voted because the broker/dealer or other nominee does not have the authority to vote on a particular matter) will be counted as Shares that are present and entitled to vote for the purposes of determining the presence of a quorum for the Meeting.

In accordance with rules of the Securities and Exchange Commission (the "SEC"), we are furnishing our proxy materials related to the Meeting primarily via the Internet, instead of mailing printed copies of those materials to each Shareholder. Beginning on or around April 17, 2025, we will mail a Notice of Internet Availability to our Shareholders (other than those who had previously requested electronic or paper delivery) containing instructions on how to access our proxy materials, including this Proxy Statement and our annual report for 2024 (the "2024 Annual Report"), which includes our annual report on Form 10-K for the fiscal year ended December 31, 2024 (the "Form 10-K" or "2024 Form 10-K"). The Notice of Internet Availability also instructs you on how to vote over the Internet. This process is designed to expedite Shareholders' receipt of proxy materials, lower the cost of the Meeting and help conserve natural resources. However, if you would prefer to receive printed proxy materials, please follow the instructions included in the Notice of Internet Availability. If you have previously elected to receive our proxy materials electronically, you will continue to receive these materials via e-mail unless you elect otherwise. This Proxy Statement, accompanying Proxy and the 2024 Annual Report will be available on or around April 17, 2025 on our corporate website and at www.proxyvote.com and www.investorvote.com/merc for Shareholders.

Proxies may also be solicited by mail, telephone, facsimile or personal contact by our directors, officers or regular employees without additional compensation. All proxy-soliciting expenses in connection with the solicitation of votes for the Meeting will be borne by us. We also will request brokerage firms, banks, nominee custodians and fiduciaries to forward proxy materials to beneficial owners of our Shares as of the Record Date (as defined below) and will reimburse them for the cost of forwarding the proxy materials in accordance with customary practice.

Our board of directors (the "Board") has set the close of business on March 27, 2025 as the record date (the "Record Date") for the determination of Shareholders entitled to notice of and to vote at the Meeting or any adjournment, postponement or rescheduling thereof.

You are entitled to attend the Meeting only if you were a Shareholder as of the close of business on the Record Date, or hold a valid Proxy for the Meeting. In order to be admitted to the Meeting, you must present proof of ownership of Shares on the Record Date. This can be any of the following:

Shareholders and Proxy holders must also present a form of photo identification such as a driver's license. We will be unable to admit anyone who does not present identification or refuses to comply with our security procedures. You may also attend the Meeting via the Internet. The accompanying proxy materials include instructions on how to participate in the Meeting and how you may vote your Shares if you participate electronically. To submit your questions during the Meeting, please log on to www.meetnow.global/MZDKCKM. You will need to enter the 15-digit control number received with your Proxy or Notice of Internet Availability of proxy materials to enter the Meeting.

If you hold your Shares through a broker or other nominee and wish to attend the Meeting you will need to obtain a legal proxy from such broker or other nominee and send it, along with your name and email address to our registrar transfer agent by email at legalproxy@computershare.com or mail at Mercer International Legal Proxy c/o Computershare, Inc., P.O. Box 43001, Providence, RI 02940-3001. Such requests must be labelled "Legal Proxy" and must be received by Computershare no later than 5:00 p.m. (Eastern Time) on May 28, 2025.

PROPOSAL 1 – ELECTION OF DIRECTORS

In accordance with our articles of incorporation and bylaws, each as may be amended from time to time, our Board is authorized to fix the number of our directors at not less than three (3) and not more than thirteen (13) and has fixed the number of directors at ten (10) for election at the Meeting. Directors are elected at each annual meeting of Shareholders to hold office until the next annual meeting. The persons identified below are nominated to be elected at the Meeting for the ensuing year. Other than Markwart von Pentz, all of the nominees are currently directors previously elected by Shareholders. Despite the expiration of a director's term, the director shall continue to serve until the director's successor is elected and qualified or until there is a decrease in the number of directors. If for any unforeseen reason any of the nominees for director declines or is unable to serve, Proxies will be voted for the election of such other person or persons as shall be designated by the directors. Our Board has no reason to believe that any of the nominees will be unable or will decline to serve, if elected. Proxies received which do not specify a choice for the election of the nominees will be voted "FOR" each of the nominees. Proxies cannot be voted for more than ten (10) persons since that is the total number of nominees.

Set forth below is certain information furnished to us by the director nominees. There are no family relationships among any of our current directors, nominees or executive officers. None of the corporations or other organizations referenced in the biographical information below is a parent, subsidiary or other affiliate of ours.

We believe that our directors should satisfy a number of qualifications, including demonstrated integrity, a record of personal accomplishments, a commitment to participation in Board activities and other traits discussed below in "Our Director Nominations Process". We believe that Mercer and all of its stakeholders benefit from the broader exchange of perspectives and balance brought by a diversity of background, thought and experience. We further believe that a diverse and balanced Board enhances our sustainability, understanding of risks and opportunities, decision-making processes and achievement of our strategic goals. We also endeavor to have a Board representing a range of skills and depth of experience in areas that are relevant to and contribute to the Board's oversight of our operations. The Board believes its current size is appropriate for the size and scope of our business.

We believe that the following nominees represent a desirable mix of backgrounds, skills and experiences. Additionally, we believe that the specific leadership skills and other experiences of the nominees described below, particularly in the areas of forest products industry or related business experience, senior executive leadership, financial accounting/reporting, public company board experience, investment management, capital markets and finance, provide us with the perspectives and judgment necessary to guide our strategies and monitor their execution.

Each nominee elected as a director is expected to dedicate sufficient time, energy and attention to ensure the diligent performance of such director's duties, including by attending meetings of our Shareholders and meetings of the Board and committees of which such director is a member.

Following the biographical information for each director nominee, we describe the key experience, qualifications and skills our director nominees bring to the Board that, for reasons discussed below, are important in our business and a Board diversity mix.

The Board considered these experiences, qualifications and skills and the directors' other qualifications in determining to recommend that the directors be nominated for election:

Nominees for Election as Directors

Majority Voting Policy in Uncontested Director Elections

In order to provide Shareholders with a meaningful role in the outcome of director elections, our Board has adopted a provision on voting for directors in uncontested elections as part of our Corporate Governance Guidelines (the "Governance Guidelines"). This provision provides that any nominee in an uncontested election who receives more votes "Against" for his or her election than votes "For" his or her election shall have his or her term as a director terminate on the earliest to occur of: (i) 90 days after the date the election results are certified; (ii) the date such director resigns; or (iii) the date the Board fills the position. We have amended our bylaws to reflect such provision.

The complete terms of this provision are included in our Governance Guidelines which can be found at the "Governance" link on our website at www.mercerint.com.

The election of directors at the Meeting is an uncontested election.

Board Snapshot

The following tables provide a snapshot of the independence, tenure, age, diversity and geographic mix of our director nominees.

In 2024, we revised our internal governance structure and Governance Guidelines to replace the lead director role with an independent Chairperson.

Board Tenure and Refreshment

Maintaining an appropriate balance of tenure among directors is an integral part of the Board's consideration. Longer serving directors bring valuable experience and knowledge with respect to our business, industry and strategic and operational challenges. Newer directors bring, along with their own personal experiences, fresh perspective and ideas.

We have added two new directors to the Board over the last three years, including our Chief Executive Officer, Juan Carlos Bueno, and not including Markwart von Pentz, who will be standing for election as a new independent director nominee at the upcoming Meeting. If Mr. von Pentz is elected at the Meeting, we will have added five (5) new independent directors to the Board over the last five years.

We do not believe that directors should be subject to term or age limits. While term and age limits could facilitate fresh ideas and viewpoints being consistently brought to the Board, we believe they are counter-balanced by the disadvantage of causing the loss of directors who, over a period of time, have developed insight into our strategies, operations and risks and continue to provide valuable contributions to Board deliberations. We believe that our decision not to establish term or age limits is consistent with the prevailing practice among companies in the S&P 500. We recognize that certain governance stakeholders have suggested that longer-serving directors may have decreased independence and objectivity; however, we believe that arbitrarily removing knowledgeable directors and the oversight consistency they bring – particularly during periods of management change – weighs against strict restrictions on director tenure. We also believe flexibility in Board size allows us to provide continuity, bringing new perspectives while preserving the knowledge and experience of our Company that longer-serving directors have. Ultimately, it is our Board's responsibility to establish Board refreshment policies, using its discretion in our best interests and that of our Shareholders.

Snapshot of Attributes of Director Nominees

All director nominees exhibit the following personal attributes:

Our director nominees also have the following qualifications and attributes:

Board Diversity

We recognize the benefit of diversity of perspectives, backgrounds, skills and experience and consider it to be an element of Board effectiveness. We believe such diversity provides us with a better understanding of issues, enhances our decision making, improves our execution and performance, enhances our oversight of risk, ESG matters and strategies and enhances value for Shareholders and other stakeholders.

Currently, 30% of our Board is comprised of directors who are women. If all of the Board nominees are elected at the Meeting, 30% of our Board will continue to be comprised of women.

CORPORATE GOVERNANCE AND BOARD MATTERS

Role of the Board

Our Board makes major policy decisions, participates in strategic planning, oversees risk management, oversees our sustainability and ESG initiatives and reviews management's performance and effectiveness. Certain important matters must be dealt with by our Board, such as the approval of financial statements and the declaration of dividends to our Shareholders. Through our Governance Guidelines and/or formal resolution, the Board reserves for itself the right to make certain decisions and delegates others to management. In some matters, management's discretion is limited by dollar thresholds beyond which Board approval is required.

Our Board, with management, also sets the tone from the top to set high standards of conduct and promote an open and transparent culture. The Board's responsibility to oversee conduct and culture is broad and focuses on continuous improvement in our affairs.

Key Areas of Board Oversight

Governance Guidelines, Code of Conduct and Other Policies Available on Our Website

The Governance section of our website (https://mercerint.com/our-company/governance/) contains our policies regarding our governance and other practices including our:

We have adopted Governance Guidelines which provide a set of flexible guidelines for the effective functioning of our Board which are reviewed regularly and revised as necessary or appropriate in response to changing regulatory requirements and evolving best practices.

Our Governance Guidelines also:

Our Code of Business Conduct and Ethics provides a framework of fundamental principles that guide the Board in its deliberations, allows us to address sensitive and complex matters and sets forth our accountabilities if standards of conduct are not upheld.

Our Code of Business Conduct and Ethics, which applies to all of our executives, employees and directors, is designed to deter wrongdoing and promote:

In 2023, the SEC approved the NASDAQ's proposed rules implementing the incentive-based compensation recovery provisions of the Dodd-Frank Wall Street Reform and Consumer Protection Act, which require listed issuers to develop and implement a policy providing for the recovery of erroneously awarded incentive-based compensation received by current or former executive officers and to satisfy related disclosure obligations. As a result, we amended and restated our Clawback Policy, which provides procedures which allow us to seek reimbursement with respect to incentive compensation paid or awarded to executive officers in the event of an accounting restatement resulting from material noncompliance with financial reporting requirements under the federal securities laws of the United States and in certain other cases of misconduct. Further, our policy additionally provides for forfeiture or clawbacks of awards in specified cases where we determine an executive has engaged in material misconduct, material failure to comply with our policies or personal misconduct that is detrimental to us.

We encourage a transparent and open environment where all employees can speak up without reprimand. Our Whistleblower Policy provides a set of procedures for our employees to report, on a confidential basis, their concerns or complaints about questionable accounting or auditing matters or violations of legal or regulatory requirements and for the Audit Committee to receive and respond to such concerns and complaints. Accordingly, our employees can report any misconduct to a supervisor, manager, or the Audit Committee, or employees can make reports and raise concerns on a confidential basis through our Integrity Hotline.

Our Securities Law Compliance Policy applies to the handling of material non-public information related to us or other companies with whom we deal and the buying, selling or other dispositions of our stock and other securities and those of other companies. Our Securities Law Compliance Policy applies to all of our directors, employees and agents and is designed to promote compliance with insider trading laws, rules and regulations, and the NASDAQ listing standards. Except as permitted by the policy, no director, employee, or agent may purchase or sell our securities or of any other company with whom we deal while aware of material, nonpublic information concerning us or the other company until at least two full trading days have elapsed after the public disclosure of the information. Furthermore, no director, employee or agent shall disclose material non-public information about us or any company with whom we deal to anyone outside our organization unless authorized to do so. It is also our policy to comply with all applicable securities laws when transacting in our own securities.

Our Hedging Transactions Policy, which applies to our directors and all of our executive officers, is designed to prohibit such individuals from hedging their Mercer stock, including trading in options, puts, calls or other derivative instruments relating to our securities.

Our Anti-Corruption Policy is designed to expand upon the provisions of our Code of Business Conduct and Ethics relating to international operations and ensure compliance by us and our directors, officers, employees and agents with the United States Foreign Corrupt Practices Act of 1977 (the "Foreign Corrupt Practices Act") and other applicable anti-corruption laws.

We periodically conduct management online training sessions to increase awareness and educate our management on the Foreign Corrupt Practices Act and other similar foreign corrupt practices rules and regulations.