Unitil Corporation

2024 Proxy Statement

Notice of Annual Meeting of Shareholders

Wednesday, May 1, 2024

11:30 a.m. EDT

Hampton, New Hampshire

March 29, 2024

Dear Fellow Shareholder,

I am pleased to invite you to the Unitil Corporation Annual Meeting of Shareholders to be held on Wednesday, May 1, 2024, at 11:30 a.m. EDT, at our corporate headquarters, 6 Liberty Lane West, Hampton, New Hampshire 03842-1720.

This year, we are asking shareholders to vote on the election of three directors, on the approval of the Company’s Third Amended and Restated 2003 Stock Plan, and on the ratification of the selection of independent registered public accountants. Also, this year, shareholders will be presented with an advisory vote on executive compensation.

Your vote is very important. We encourage you to vote to ensure that your voice is represented at the meeting, and to play a part in our future. The enclosed proxy materials provide important information to assist you with your voting decisions and instructions to submit your vote.

I would like to thank you for choosing to invest in Unitil Corporation. Throughout 2023, we honored our commitments to our shareholders, customers, employees, local communities and partners by investing in people, technology, and assets, delivering exceptional customer service, and producing strong financial results. Looking forward, our disciplined approach to operating excellence, financial integrity, and strategy execution will continue to support those commitments.

On behalf of the Board of Directors and management of Unitil Corporation, thank you for your continued support and confidence in 2024.

Sincerely,

Thomas P. Meissner, Jr.

Chairman of the Board and

Chief Executive Officer

NOTICE OF ANNUAL MEETING OF SHAREHOLDERS

The Unitil Corporation (the “Company”) 2024 Annual Meeting of Shareholders will be held at the office of the Company, 6 Liberty Lane West, Hampton, New Hampshire 03842-1720, on Wednesday, May 1, 2024, at 11:30 a.m. EDT for the following purposes:

The Board of Directors set February 23, 2024, as the date for determining holders of record of common stock who are entitled to notice of and to vote at the meeting or at any adjournments or postponements of the meeting. The Board of Directors has directed the Company to prepare this notice, the accompanying proxy statement, and the accompanying annual report, and to send them to you.

By Order of the Board of Directors,

Sandra L. Whitney

Corporate Secretary

YOUR VOTE IS IMPORTANT

Your vote is important. To ensure a quorum is present at the Annual Meeting of Shareholders, please be sure your shares are represented at the meeting.

You may vote in one of the following ways:

ATTENDING THE ANNUAL MEETING OF SHAREHOLDERS

All shareholders may attend the Annual Meeting of Shareholders. However, to ensure that the meeting remains orderly and secure, you must follow certain procedures for admittance.

Attending in Person

Shareholders of record will need to provide their name and government-issued picture identification. Beneficial owners will need to provide a copy of an account statement from the bank, broker or nominee holding the shares as proof of ownership as of the Record Date, as well as government-issued picture identification. The safety of our employees and all invited guests and visitors is of primary importance. If you should elect to attend the Annual Meeting in person, you will be expected to follow all directions from Company personnel while inside our corporate office.

TABLE OF CONTENTS

PROXY STATEMENT 

Unitil Corporation

6 Liberty Lane West

Hampton, NH 03842-1720

March 29, 2024

PROXY STATEMENT

Unitil Corporation (“Unitil” or the “Company”) is providing this proxy statement and the accompanying annual report (which includes the Company’s Annual Report on Form 10-K for fiscal year 2023) to shareholders in connection with our 2024 Annual Meeting of Shareholders (the “Annual Meeting”). The Board of Directors (the “Board”) is soliciting your designation of a proxy to vote your shares at the Annual Meeting. As a shareholder of Unitil, you are invited to the Annual Meeting, as well as entitled and requested to vote (if you are a shareholder of record) or to provide voting instructions (if you beneficially own your shares in street name) on the proposals described in this proxy statement. This proxy statement provides information to assist you in voting your shares or in providing voting instructions with respect to your shares.

Unitil has the following subsidiaries, which are referred to throughout this proxy statement: Fitchburg Gas and Electric Light Company (“Fitchburg”); Granite State Gas Transmission, Inc. (“Granite”); Northern Utilities, Inc. (“Northern”); Unitil Energy Systems, Inc. (“Unitil Energy”); Unitil Power Corp.; Unitil Realty Corp.; Unitil Resources, Inc.; and Unitil Service Corp.

We may also refer to Unitil as “we” or “our” or “us” throughout this proxy statement.

Date, Time and Place

The Annual Meeting will be held on Wednesday, May 1, 2024, at 11:30 a.m. EDT, at our corporate office, 6 Liberty Lane West, Hampton, New Hampshire 03842-1720.

Anticipated Mailing Date

We anticipate first mailing definitive copies of this proxy statement, the accompanying proxy card, and the accompanying annual report to shareholders on or about March 29, 2024.

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MEETING SUMMARY

This year, we are seeking your vote on the following proposals:

QUORUM & REQUIRED VOTE

A majority of the outstanding shares of common stock entitled to vote at the Annual Meeting must be present in person or represented by proxy to conduct the Annual Meeting. This is referred to as a quorum.

If a quorum is present, the nominees standing for election as a Director will be elected by a plurality of the votes cast by the shareholders. Votes withheld and broker non-votes will not be counted toward the achievement of a plurality. Additional information concerning the election of directors appears in the

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sections entitled Corporate Governance – Resignation Policy and Proposal 1 – Election of Directors. With respect to all other matters that may come before the Annual Meeting, action on a matter is approved if the votes cast favoring the action exceed the votes cast opposing the action. Therefore, abstentions and broker non-votes will have no effect on the other matters. Representatives of our transfer agent will count the votes and certify the results.

VOTING RIGHTS & PROCEDURES

As an owner of Unitil common stock, it is your legal right to vote (or to provide voting instructions) on all matters to be considered at a shareholder meeting. We hope you will exercise your legal right and fully participate as a shareholder in the Annual Meeting. You may cast one vote for each share of common stock that you own on all matters presented at the Annual Meeting.

The Board has selected and approved Robert B. Hevert, Daniel J. Hurstak, and Thomas P. Meissner, Jr. as proxies for the Annual Meeting to vote your shares in the manner that you specify on the proxy card or via the Internet, or if you do not give any specification on your proxy card or submitted proxy with respect to a matter, FOR such matter. Your designation of a proxy will not affect your right to attend the Annual Meeting and vote at the meeting.

Record Holders

If your shares of common stock were registered directly in your name with our transfer agent as of the Record Date, then you are considered a shareholder of record of the shares (a “Record Holder”) and we have sent the proxy materials and the accompanying proxy card directly to you.

Beneficial Holders

If your shares of common stock were registered in the name of a bank, broker or other nominee as of the Record Date, then you are considered a beneficial owner (“Beneficial Holder”) of the shares that are registered in street name, and your bank, broker or other nominee has sent this proxy statement and voting instructions to you. As a Beneficial Holder, your shares may be voted even if voting instructions are not provided.

Brokerage firms have the authority under New York Stock Exchange (“NYSE”) rules to vote shares for which their customers do not provide voting instructions on routine matters. The ratification of the selection of our independent registered public accounting firm, Deloitte & Touche LLP, for fiscal year 2024 is considered a routine matter. When a proposal is not routine and the brokerage firm has not received voting instructions from its customers, the brokerage firm cannot vote the shares on that proposal. Those shares are considered “broker non-votes.” Please note that, under NYSE rules, this means that brokers may not vote your shares on Proposals 1, 2 and 4 at the 2024 Annual Meeting if you have not given specific instructions as to how to vote to the broker. Please be sure to give specific voting instructions to your broker so that your vote can be counted.

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A MESSAGE FROM TOM MEISSNER, CHAIRMAN & CHIEF EXECUTIVE OFFICER 

While 2023 was once again a challenging year with economic uncertainty, continuing post-pandemic economic distortion, and other disruptive world events, at year end, we achieved record earnings of $45.2 million or $2.82 per share, a 9% increase over the $2.59 per share earned in 2022. This marks the third consecutive year that we delivered earnings growth above the high end of our 5%—7% guidance in a challenging macro environment. We continued to accelerate dividend growth for our investors, and, we were one of the few utilities to provide positive shareholder return for the year. Operationally, we once again achieved outstanding results in electric reliability and gas emergency response, and maintained our exceptional track record in gas pipeline safety. Customer satisfaction continues to be exceptional and we were again the top ranked utility company in the northeast. These accomplishments reflect strong leadership, commitment to financial integrity and operational excellence, informed management of risk and strategic planning, and our steadfast drive to advance new technologies to achieve the greater goal of a clean energy future. I am very proud of our collective accomplishments in another challenging year.

Our accomplishments over the past year would not have been possible without our team of dedicated employees. Our employees are the lifeblood of our Company. They are motivated and engaged. Their dedication is inspiring and reflected in the exceptional service we deliver to our customers each and every day. This collective effort leads to the outstanding financial performance our shareholders have come to expect.

Our industry is at the forefront of an unprecedented transformation to reduce emissions and meet society’s climate goals—the transition to clean energy. We know the transition will be lengthy and complex, and that no single strategy or technology will achieve all our long-term strategic and sustainability objectives. But our future prospects for delivering long-term growth have never been better. The clean energy transition offers abundant opportunities to accelerate customer growth, invest in electric and gas infrastructure, and develop new sources of renewable energy that will position our Company for sustained long-term growth in the coming years.

As we move forward in 2024, I am optimistic about the year ahead. Over the last decade, we have grown and prospered like never before in our Company’s history, and I am confident that the initiatives and actions we are taking today will shape the successes of tomorrow. We are excited by and ready for the opportunities that lie ahead. As we look to the future, there are two basic principles that I feel are important to confirm: We will continue to invest in the people, technology and assets upon which we rely to deliver exceptional service; and we will maintain our focus on financial discipline and integrity. It is truly an exciting time to be a part of the energy industry, and I am so pleased you’ve chosen to share in our journey. If the last decade is any indicator, the future is indeed bright.

March 29, 2024

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ACTING ON OUR VALUES

Our RISE values are the guiding principles behind our actions, but they are only as good as they are meaningful and measurable. Continued focus on the importance of these values will drive our commitment to deliver ‘energy for life’ and the achievement of a clean and sustainable energy future for all of our stakeholders.

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The table below shows Executive Officers’ biographical information as of the date of this proxy statement, including the Named Executive Officers.

MANAGEMENT INFORMATION TABLE

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The following table sets forth information on the beneficial ownership of our common stock as of the Record Date, by (i) each person known to us to be the beneficial owner of more than five percent of our common stock, (ii) each Director and nominee for Director, (iii) each executive officer named in the Summary Compensation Table in the section entitled Compensation - Compensation of Named Executive Officers (the “Named Executive Officers”) and (iv) all Directors and executive officers of Unitil as a group. Except as otherwise indicated, to our knowledge, the beneficial owners listed have sole voting and sole dispositive power with respect to the shares beneficially owned by them. The address of each of Unitil’s Directors and executive officers is c/o Unitil Corporation, 6 Liberty Lane West, Hampton, New Hampshire 03842-1720.

BENEFICIAL OWNERSHIP

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NOTES:

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SECTION 16(a) BENEFICIAL OWNERSHIP REPORTING COMPLIANCE

Section 16(a) of the Securities Exchange Act of 1934 (“Exchange Act”) requires our executive officers, Directors, and persons who beneficially own more than ten percent of a registered class of our equity securities to file certain reports of ownership and changes in share ownership with the Securities and Exchange Commission (“SEC”) and the NYSE. Based upon our review of such forms that were filed in 2023, and written representations from certain reporting persons that such forms were not required to be filed by those persons for the reporting year 2023, we believe that all filing requirements applicable to our officers and Directors during 2023 and through March 2024, were met.

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We are committed to comprehensive and effective corporate governance practices. The Board and the management team firmly believe that solid corporate governance is key to the transparent and ethical operation of our Company and have set a high standard for this important element in our long-term sustainability and growth goals.

The ethical character, integrity and principles of the Board, senior management, and our employees remain the most important safeguards of good corporate governance. These attributes are inherent to engaged leadership, effective management structure, and a committed, carefully-trained workforce.

The Corporate Governance Guidelines and Policies of the Board (the “Governance Guidelines”) inform the pursuit of superior Board function, management accountability, effective and transparent disclosure, and financial integrity. Together with the Bylaws and the Code of Ethics Policy, the Governance Guidelines provide us with a strong governance framework.

The Governance Guidelines represent the current view of the Board on governance and should not be viewed as rigid constraints. We will continue to monitor new developments and requirements, as well as emerging issues concerning corporate governance best practices and financial disclosure, and will adopt changes and new policies as appropriate. The Governance Guidelines are reviewed regularly and are subject to modification from time to time by the Board. The Governance Guidelines are available for review on the Corporate Governance page of the Investor Relations section of our website at unitil.com/investors, and are available in print to any shareholder or other interested party free of charge upon request to the Corporate Secretary at 1-800-999-6501 or at the address listed in the section entitled Information about the Annual Meeting.

ROLE OF THE BOARD   The Board is elected by our shareholders to oversee the long-term health and overall success of our business and to ensure our ongoing financial strength. The Board serves as the ultimate decision-making body on all matters, except for those reserved for or shared with our shareholders or committees of the Board.

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RISK OVERSIGHT

The Board is responsible for the oversight of management, the development of Company policy and strategy, and the ongoing assessment of the Company’s operational effectiveness and financial strength, which includes the oversight of risk. The Board’s ultimate goals are to ensure that Unitil continues as a successful and sustainable business, to optimize financial returns in light of the business risks, to increase shareholder value over time, and to protect the interests of all stakeholders.

Our Enterprise Risk Management (“ERM”) program has been in place since 2014. The Board has definitive oversight responsibility for the ERM program in accordance with its fiduciary duty. The ERM program is a foundation for risk management that is relevant, sustainable and scalable. The ERM program is designed to identify existing and potential risks, and to manage risks within our risk appetite in order to sustain operations and achieve business and strategic objectives. Our ERM program includes regular review of new or emerging risks, the assessment of such risks and their potential effects on our Company, the velocity of potential incidents resulting from such risks, and risk mitigation strategies. In building the ERM program, the potential risks relating to our business were defined using a comprehensive set of risk disclosures which are described in Part I, Item 1A. Risk Factors of our 2023 Annual Report on Form 10-K filed with the SEC on February 13, 2024 (“2023 Form 10-K”).

In its oversight role, the Board is supported by the Risk and Compliance Committee (the “RCC”), a multi-function management committee that is responsible for the ongoing development and implementation of the ERM program and associated risk management standards. The ERM program is integrated with other assurance and strategy-related functions throughout our Company to ensure appropriate coverage of risks that could impact us. In addition to known risks, the ERM provides for the identification of emerging risks, through participation in industry groups, scenario planning and gap analysis, discussions with designated internal subject matter experts, and in consultation with outside advisers. Management then analyzes the emerging risks to determine materiality, likelihood, impact, velocity, and appropriate mitigation strategies. A quarterly ERM report, outlining both emerging and ongoing risks as well as management’s mitigation efforts, is provided to the Board at each Board meeting.

Our statements of risk appetite and risk tolerance were developed as a joint effort between management and the Board. The importance of the integration of clear statements of risk appetite and risk tolerance to strategy development and implementation were the primary factors considered during this exercise. The Board was guided through the process with management’s input and information from the RCC’s work with regard to known risks, emerging risks, and opportunities created by well-managed risk. At the conclusion of the exercise, the Board determined our risk appetite and risk tolerance as noted below.

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Like all companies, we face a variety of risks, both internal and external, and many factors work simultaneously to affect our overall business risk. The Board recognizes that our business risk is not static, and that it is not possible to mitigate all risk and uncertainty. The Board works within a climate of respect and candor, fostering a culture of open dialogue between Board members and senior management, which includes comprehensive knowledge of our many elements of risk. Overall, the Board believes that a systematic and proactive approach to properly oversee risk management has been defined and enhanced by the ERM program, which will continue to evolve through ongoing review and assessment of the existing and emerging risks facing the Company.

CYBERSECURITY OVERSIGHT

The Board is responsible for oversight of cybersecurity, which is and will continue to be a primary focus. The Board recognizes the protection of our data, customer information and infrastructure are critical to the ongoing success and prosperity of our Company, and the Board’s decision to elevate oversight of cybersecurity to the Board is appropriate and a matter of good governance.

We maintain a robust Cybersecurity Plan for assessing, identifying, and managing material risks from cybersecurity threats. The intent of the Cybersecurity Plan is to provide a proactive and systemic approach to meet the evolving requirements for cybersecurity and related compliance in the utility industry. The Cybersecurity Plan is part of our ERM program, described above, and the Board receives regular cybersecurity updates as part of the ERM report. The Cybersecurity Plan includes annual assessments, the results of which are used to benchmark our cybersecurity posture, to identify risks from cybersecurity threats, to prioritize any such risks that may have potential material effects on our Company, and to establish effective controls to manage, mitigate and remediate such risks.

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LEADERSHIP STRUCTURE

The current leadership structure of the Board consists of a combined chairman and chief executive officer (“CEO”) position which has been held by Mr. Meissner since April 2018.

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BOARD SUCCESSION PLAN

The Board is engaged in ongoing succession planning, which is led by the Nominating and Governance Committee. The Board Succession Plan addresses upcoming retirements, committee membership and rotation, class balancing, skill set requirements and gaps, and planning for unforeseen events. The Board Succession Plan is also directly linked to both new director recruitment actions and diversity goals.

RETIREMENT POLICY

In general, no Director may be nominated as a candidate for re-election as part of the slate of Directors that we propose, nor may any person be nominated as a candidate for election, after he or she has reached age 75. Directors are not subject to specific term limits. Due to the complexity of the utility industry, we value the insight that a Director is able to develop over a period of time. The Board believes that tenure provides an enhanced contribution to the Board, including the benefits of valuable experience and familiarity. However, the Board seeks to balance tenure on the Board in the context of overall diversity, as well as to protect against an entrenched Board.

DIRECTORS’ STOCK OWNERSHIP AND RETENTION POLICY

The Board believes that its members should make the financial commitment to own a significant number of shares of our common stock to properly align their interests with those of our shareholders. All non-employee Directors must own shares of common stock in the equivalent value of three times the current annual cash retainer for Board service. Shares of restricted stock and restricted stock units (“RSUs”) are counted towards this total. The ownership requirement is calculated annually on January 1, and as of January 1, 2024, the current ownership requirement is $195,000 in value. Mr. Brown, Mr. Collin, Ms. Foster, Mr. Godfrey, Mr. Green, Ms. Vogel and Mr. Whiteley meet the stock ownership requirement. Any new Director who joins the Board has four years from the date of first election to the Board by shareholders to accumulate the required number of shares of common stock, which currently applies to Ms. Alonzo and Ms. Awad. Additionally, all members of the Board are required to hold all forms of equity received from the Company until retirement or other separation from the Company. For Board members, this includes all forms of equity received as part of the annual retainer for Board service. The Board, in its sole discretion, may approve a waiver to this policy as circumstances may warrant. To date, no such waivers have been proposed or approved.

RESIGNATION POLICY

A Director is required to tender his or her resignation if he or she receives a “withhold” vote greater than 50% of the shares voted at the annual meeting of shareholders in an uncontested election. If an incumbent Director fails to receive the required vote for re-election, the Nominating and Governance Committee will act on an expedited basis to determine whether to recommend the acceptance of the Director’s resignation

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and will submit such recommendation for prompt consideration by the Board. The Director whose resignation is under consideration shall abstain from participating in any decision regarding that resignation. The Nominating and Governance Committee and the Board may consider any factors they deem relevant in deciding whether to accept a Director’s resignation.

The Board nominates for election or re-election to the Board only candidates who agree to tender, promptly following the annual meeting at which they face election or re-election as Director, irrevocable resignations that will be effective upon (i) the failure to receive the required vote at the annual meeting at which they face re-election and (ii) Board acceptance of such resignation. In addition, the Board fills board seat vacancies and new directorships only with candidates who agree to tender, promptly following their appointment to the Board, the same form of resignation tendered by other Directors in accordance with this policy. All candidates proposed for election or re-election at the Annual Meeting have agreed in writing to abide by this policy.

Directors are encouraged to attend the Annual Meeting, although there is no formal requirement to attend. In 2023, ten Directors attended the Annual Meeting.

EXECUTIVE SESSIONS

Non-employee members of the Board have the opportunity to meet in executive session, without members of management present, either prior to the start or following the adjournment of each Board and committee meeting. During 2023, the Board met in executive session on four occasions. Mr. Green, the Lead Director, presided at all four meetings.

ANNUAL EVALUATION

We seek guidance and insight from all Board members on key Board, Company, and industry-related issues annually. This exercise has proven to be a beneficial communication tool, a measurement of Board philosophy, and a commitment to excellence in corporate governance. In 2023, all Board members participated in the evaluation process, which consisted of two parts – the evaluation questionnaire and the self-assessment.

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Evaluation Questionnaire

The evaluation questionnaire (the “Questionnaire”) provides a platform for expression of thoughts and opinions regarding various issues facing the Company, the Board as a whole, as well as any committee(s) upon which individual Board members may serve. Its intended use is as a communication tool to enhance the Board’s overall effectiveness in a changing business environment. Board effectiveness contributes to the sustainability of our Company over the long term, and therefore is of vital importance to shareholders and all stakeholders. The Questionnaire is presented as a series of questions requiring qualitative responses to reflect individual opinions and viewpoints.

Self-Assessment

The individual Board member self-assessment is a voluntary confidential personal improvement tool intended to encourage honest reflection on personal characteristics, behavior, and aspirations with regard service on the Board.

CODE OF ETHICS

Our Code of Ethics (the “Code of Ethics”) is a robust statement of our high standards for ethical behavior, legal compliance and financial disclosure, and is applicable to all of our Directors, officers and employees. The Board unanimously approved the Code of Ethics in 2004, and along with all officers and employees, annually affirms understanding of, and agreement and compliance with, the Code of Ethics. The Nominating and Governance Committee reviews the Code of Ethics annually for any required or desirable revisions. Should the Board adopt any changes to, or waivers of, the Code of Ethics, those changes or waivers will be promptly disclosed and posted on our website at the address noted below. To date, there have been no changes to or waivers requested or granted with regard to the Code of Ethics. The Nominating and Governance Committee last reviewed the Code of Ethics on January 30, 2024. A copy of the Code of Ethics can be found on our website at unitil.com/investors.

MANAGEMENT SUCCESSION PLANNING

Effective executive leadership is critical to our success. The Board oversees the senior management succession planning process to ensure that effective plans are in place for succession of the CEO, as well as other key senior management positions. The succession plan addresses contingencies for retirement, resignation, death, disability, or other untimely departure of the CEO and/or other members of senior management for a smooth transition on both an interim and long-term basis. In 2019, the management succession plan was evaluated for gaps and other risk factors. As a result of that evaluation, in 2020, the management succession plan was expanded and developed further to include middle management and other key positions, including long-serving employees nearing retirement. To date, seven key internal candidates have been identified as potential future leaders of our Company. Senior management continues to mentor this group on executive development, strategy development, corporate decision-making, and outlook for long-term growth. The management succession plan is an ongoing and fluid process that is reviewed and updated regularly to

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address both immediate needs and long-term goals. We also have a comprehensive Crisis Succession Plan for key officers to establish clear succession protocol in the event of an emergency or other unplanned event. The Crisis Succession Plan is a stand-alone plan and does not replace or reduce our ongoing management succession planning efforts.

EXECUTIVE COMPENSATION RECOVERY POLICY

In October 2022, the SEC adopted final new rules related to the recovery of erroneously awarded performance-based compensation. Following that adoption, the NYSE proposed final rules which were adopted in June 2023 in accordance with the exchange’s mandate pursuant to the SEC’s final rules. The Board of Directors approved our revised Executive Compensation Recovery Policy (the “Policy”), described below, on November 1, 2023.

The purpose of the Policy is to provide for the recovery of certain executive compensation in the event of an accounting restatement resulting from material non-compliance with financial reporting requirements under the securities laws. In the event we are required to prepare an accounting restatement of our financial statements due to material non-compliance with any financial reporting requirement, we generally will be entitled to recover any excess performance-based compensation received by any current or former Covered Executive² during the three-year period immediately preceding the date on which we are required to prepare an accounting restatement. “Performance-based compensation³” is defined as all annual incentives and long-term incentives (whether in cash, in equity, or otherwise) granted, earned, vested or unvested with performance features based wholly or in part on our Company’s or a specified group’s attainment of a financial reporting measure. “Financial reporting measures” is defined as measures that are determined and presented in accordance with the accounting principles used in preparing our financial statements, and any measure(s) that are derived wholly or in part from such measures. We shall recover any erroneously awarded performance-based compensation in accordance with the Policy, with the exception that if the conditions of Rule 10D-1 of the Exchange Act and the listing standards of the NYSE are met, the Compensation Committee determines that recovery would be impractical.

All actions taken under this policy will comply with Section 10D of the Exchange Act and the listing standards of the NYSE.

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EXECUTIVE STOCK OWNERSHIP POLICY   All Named Executive Officers are required to own shares of our common stock in the equivalent value of a multiple of base salary. All shares of our common stock that are owned directly or beneficially, shares of restricted stock that are awarded, whether vested or unvested, as well any shares of Unitil common stock held in the Tax Deferred Savings and Investment Plan are counted towards the required total. Any newly appointed Named Executive Officer will have four years from the date of appointment to obtain the required shares of stock. As of the date of this proxy

EXECUTIVE STOCK RETENTION POLICY

The Board believes that our executive officers should own a significant number of shares of our common stock to properly align their interests with those of the shareholders. All Named Executive Officers are required to hold all forms of equity received as compensation until retirement or other separation from the Company. The Board, in its sole discretion, may approve a waiver to this policy as circumstances may warrant. To date, no such waivers have been proposed or approved.

PROHIBITION ON HEDGING AND/OR PLEDGING COMPANY STOCK POLICY

All members of our Board and our executive officers are prohibited from engaging in short sales or engaging in any hedging transaction with respect to our common stock, as well as engaging in any transactions that result in pledging, or using as collateral, shares of our common stock in order to secure personal loans or other obligations, including any shares that may be held in a margin account.

TRANSACTIONS WITH RELATED PERSONS

The Audit Committee is responsible for reviewing and approving, as appropriate, all Related Person Transactions (as defined below), in accordance with its charter (the “Audit Committee Charter”) and as prescribed in the NYSE Listed Company Manual, Section 314, Related Person Transactions. As a result, the

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Committee has adopted procedures for such review and approval and included such procedures in our Governance Guidelines. We had no Related Person Transactions requiring disclosure in 2023, and there are no Related Person Transactions requiring disclosure currently proposed for 2024. “Related Person” and “Related Person Transaction” are defined in Item 404(a) of Regulation S-K (“Regulation S-K”), as prescribed under the Securities Act of 1933, as amended (the “Securities Act”).

Transactions between us or one or more of our subsidiaries and one or more Related Person may present risks or conflicts of interest or the appearance of conflicts of interest. Our Code of Ethics generally requires all employees, officers and Directors to avoid engagement in activities or relationships that conflict, or would be perceived to conflict, with our interests or adversely affect our reputation. It is understood, however, that certain relationships or transactions may arise that would be deemed acceptable and appropriate upon full disclosure of the transaction, following review and approval to ensure there is a legitimate business reason for the transaction and that the terms of the transaction are no less favorable to us than could be obtained from an unrelated person.

In connection with the review and approval, if appropriate, of any Related Person Transaction, the Audit Committee will consider whether the transaction will compromise our professional standards included in our Code of Ethics. In the case of any Related Person Transaction involving an outside Director or nominee for Director, the Committee will also consider whether the transaction will compromise the Director’s status as an independent Director as prescribed in the NYSE Listed Company Manual, Section 303A, Independent Directors. The procedures followed by the Committee to evaluate transactions with Related Persons are also available on the Corporate Governance page of the Investor Relations section of our website at unitil.com/investors.

COMMUNICATION WITH THE BOARD

Shareholders and other interested parties who desire to communicate with the Board, a committee of the Board, the non-management or independent Directors as a group, or an individual member of the Board

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may do so in writing by sending a letter c/o Corporate Secretary, Unitil Corporation, 6 Liberty Lane West, Hampton, New Hampshire 03842-1720 or via email to whitney@unitil.com. The Corporate Secretary will screen all correspondence for security purposes, and will also determine whether the communication relates to business matters that are relevant to us. If the correspondence meets these standards, it will be promptly forwarded to the appropriate Director(s).

NOMINATIONS

The Nominating and Governance Committee is responsible for recommending to the Board the slate of Director nominees for election by our shareholders. The Board reviews and, as appropriate, approves all Director nominees to be presented to our shareholders for election. As provided in Article III of our Bylaws, any vacancy occurring in the Board, whether due to the death, resignation or other inability to serve of any Director previously elected may be filled by the affirmative vote of a majority of the remaining Directors.

General Nomination Process

The Nominating and Governance Committee determines the required selection criteria and qualifications of Director nominees based upon the needs of the Company at the time nominees are considered. See also the section entitled Qualifications and Skills of Directors below. Director candidates will be selected based on input from Directors, executive officers, and if the Committee deems appropriate, a third-party search firm. Minimum criteria for Director nominees are set forth below, as well as in the Corporate Governance Guidelines. A candidate must possess the ability to apply good business judgment and must be in a position to properly exercise his or her duties of loyalty and care. Candidates with potential conflicts of interest will be identified and disqualified, as appropriate. The Committee shall ensure there is a robust and diverse initial pool of director candidates. In addition, the Committee will consider criteria including independence, proven leadership capabilities, business experience, areas of expertise, and factors relating to the composition of the Board, including diversity (gender, race/ethnicity, and age), size and structure. The Committee will consider these criteria for nominees identified by the Committee, by other Directors, by shareholders, or through another source. When current Board members are considered for nomination for re-election, the Committee also considers prior Board contributions, performance, meeting preparedness and attendance records.

The Committee makes a preliminary assessment of each proposed nominee based upon his or her resume and biographical information, an indication of his or her willingness to serve and other background information. This information is evaluated against the criteria set forth above as well as our specific needs at the time. Based upon a preliminary assessment of the candidate(s), those who appear best suited to meet our needs may be invited to participate in a series of interviews, which are used for further evaluation. On the basis of information collected during this process, the Committee determines which nominee(s) to recommend to the Board for approval to submit for election at the next annual meeting of shareholders, or to fill vacancies on the Board that occur between shareholder meetings. The Committee uses the same process for evaluating all nominees, regardless of the source of the nomination. The Board may elect, at its discretion, to participate in an additional round(s) of interviews with one or all candidate(s) recommended by the Committee.

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The Committee’s diligent actions and thorough recruitment process resulted in the addition of six outstanding and highly qualified Board members from 2019 through 2023, all of whom have varied and extensive experience in numerous important areas that have proven to enhance the Board’s strong skill set and diversity goals.

Shareholder Nominations

Shareholders who wish to recommend a nominee for consideration by the Committee may do so by sending the following information to the Committee c/o the Corporate Secretary at the address listed in the section entitled Corporate Governance – Governance Policies of the Board—Communication with the Board: (1) the name of the candidate with brief biographical information and his or her resume; (2) contact information for the candidate and a document evidencing the candidate’s willingness to serve as a Director if elected; and (3) a signed statement as to the submitting shareholder’s current status as a shareholder and proof of ownership of the number of shares currently held.

Additionally, nominations of persons for election to the Board made by any of our shareholders must comply with all procedures set forth in Article IV – Nomination of Directors of our Bylaws.

No candidates for Director nominees were submitted to the Committee by any shareholder in connection with the Annual Meeting.

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The Board believes there are general qualifications that all Directors must exhibit, and other qualifications, attributes, skills and experience that should be represented on the Board as a whole, but not necessarily by each Director.

Qualifications Required of All Directors

The Board requires that each Director be a person of high integrity and superior ethical character with a proven record of leadership and accomplishment in his or her chosen field. Each Director must demonstrate innovative and independent thinking, understand complex principles of business, finance, and utility regulation, and demonstrate familiarity with and respect for corporate governance requirements and practices. Directors must also comply unequivocally with the Code of Ethics, and be free of conflicts or potential conflicts of interest, and a sufficient number of Directors must meet the requirements of independence as set forth by the NYSE, as appropriate. Directors must be willing and able to dedicate the proper amount of time and effort to service on the Board as necessary to fulfill his or her responsibilities as a Director. Independent members of the Board may not serve on more than four boards of for-profit companies in addition to the Unitil Board. Non-independent members of the Board may not serve on more than two boards of for-profit companies in addition to the Unitil Board. Service on boards of non-profit organizations, other industry associations, and community or civic groups is not limited.

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Qualifications, Attributes, Skills and Experience to be Represented on the Board

The Board has identified certain qualifications, skills, experience and background that it believes are important to be represented on the Board. The Nominating and Governance Committee is charged with the responsibility of tracking the Directors’ professional experience and skill sets with a board inventory matrix (the “Skills Matrix”). The Skills Matrix is composed of 13 categories of skills and attributes considered by the Board and the Committee to be advantageous to the regulated utility business, as well as for a company of our size and complexity. The Committee uses this information to assess overall Board composition and to identify existing and potential gaps. This information is also used for recruiting and evaluation purposes when there is a vacancy, or an expected vacancy, on the Board. The Skills Matrix has proven to be a valuable tool in this assessment exercise. The Board strives to represent a meaningful cross-section of business and industry experience, education, and specialized skill sets with a group of diverse individuals who add an element of quality to our corporate governance framework, and who fairly and without compromise execute their fiduciary duty to serve the best interests of our shareholders and all of our stakeholders.

The Skill Sets Summary outlines certain essential key qualifications and experience that the Board believes should be represented on the Board for optimal oversight of our business and the effective exercise of its
		fiduciary duty to shareholders. Directors standing for re-election are also evaluated by the Committee for recommendation to the Board using a set procedure based on the expectations of Board members, which is provided to all members of the Board and reviewed annually. The evaluation includes contribution to the Board and committees served upon; unique skills, expertise and attributes; attendance and preparedness; and willingness to continue serving. Overall continuity and chemistry of the Board are also considerations, as well as factors relating to the composition of the Board, such as size and

structure, the diversity profile, and the backgrounds, perspectives, experience and skills among its members. The evaluation also includes a one-on-one meeting with Mr. Meissner to address any concerns, desire to continue serving, or any other matters. Tenure on the Board is considered to be a uniquely valuable qualification in the highly regulated utility industry, although the Board recognizes that a range of tenure is beneficial to avoid complacency and/or Board entrenchment.

In January 2024, the Nominating and Governance Committee reviewed the Skills Matrix to ensure it continues to reflect the most relevant and essential skill sets and identify any gaps in advance of the recruitment of new Board members. The Committee elected to make no changes to the Skills Matrix at this time.

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BOARD DIVERSITY

The Board’s policy is to ensure the composition of the Board reflects gender, racial and ethnic diversity. To advance the Board’s policy, the Nominating and Governance Committee ensures that the initial list of candidates from which Board nominees are chosen includes one or more qualified candidates with diversity of gender and race and/or ethnicity. Also, any external search firm retained must also include in its initial list of candidates one or more qualified candidates with diversity of gender and race and/or ethnicity.

Skills and Diversity Declaration

The skills and diversity declaration was added to the Board’s general evaluation process to provide a means for each Board member to declare their strongest skill sets and to self-identify diversity, including gender and race/ethnicity. The end use of this information is to inform ongoing accuracy of the Skills Matrix for Board succession planning needs, and to aid in our disclosure of these items as an increasing number of investors are seeking Board diversity information in our public documents. The skills and diversity declaration was included in the 2022 annual evaluation process, and other than the addition of Ms. Alonzo in April 2023, Board membership has not changed. Therefore, we used the year-end 2022 data to prepare the 2024 Skills Sets Summary. Ms. Alonzo completed the Skills and Diversity Declaration upon joining the Board in April 2023 and her responses are included in the summary. It is anticipated that the Skills and Diversity Declaration will again be included as part of the 2024 annual evaluation.

SECTION 16(a) BENEFICIAL OWNERSHIP REPORTING COMPLIANCE

The subsection entitled Section 16(a) Beneficial Ownership Reporting Compliance within the Share Ownership section of this proxy statement is incorporated herein by reference.

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		Our Commitment   Sustainability is a defining characteristic of our future success.   We have embraced the rapidly changing landscape of the utility industry as we prepare to meet the ever-changing energy needs of tomorrow and beyond. We are committed to sustainable practices and our corporate responsibilities as we work to expand clean energy choices for our
customers and ensure a reliable and affordable energy supply. Carbon reduction; clean energy; environmental stewardship; the development and safety of our employee workforce; the advancement of diversity, equity, and inclusion within our organization; and transformative energy solutions and tools for our customers are and will remain top-of-mind. Sustainability is fully embedded in our key initiatives and strategies, our leadership development and workforce planning, our RISE values (Respect, Integrity, Stewardship and Excellence) and the tone at the top.

Commitment to our Environment   We are committed to reduce Company-wide direct greenhouse gas emissions from 2019 levels by at least 50 percent by 2030, and to achieve net-zero emissions by 2050. These goals are part of our overall commitment to environmental stewardship, sustainability and corporate responsibility, and are consistent with goals established under the Paris Climate Agreement.

Commitment to our Culture and our Employees   Our long-term success is dependent on both what we do and how we do it. Our employees are our greatest asset and human capital management is paramount to our long-term success. Our employees reflect a
		long-standing culture of dedication to inspired teamwork, constant collaboration, loyalty, and the insistence on the highest possible standards for ethical business practices. Our RISE values set the tone for our actions with all stakeholders, both internal and external. These values are shared by all employees in our organization, and are a source of pride and inspiration. We believe that, collectively, employees with individual differences, life experiences, and self-expression will lead not only to a better culture, but also to our long-term success and to greater achievements along the way. We are committed to a diverse and inclusive workplace in which all employees feel valued and

respected, and embrace the genuine benefits that focused and effective human capital management brings to our organization.

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Our Approach

Tying Sustainability to Strategic Planning   Effective and informed strategic planning is essential to achieving our long-term operational and financial goals within a changing environmental and social landscape. Sustainability is embedded as a core element in our decision-making process to assist in guiding our strategic direction. Continuous focus on our strategic objectives and management of the critical success factors outlined in our strategic plan will ensure sustainable and beneficial growth for our shareholders, customers, employees, and all other stakeholders.

Aligning Sustainability and Risk Management

As climate-related risks evolve, so does the need to align sustainability and the assessment of risk. Our goal is to continuously enhance our understanding of enterprise-wide risk and uncertainty with comprehensive evaluation of current risks, scenario planning, and quantitative analysis. These tools strengthen our ability to successfully integrate sustainability into our strategic decision-making processes. By doing so, we are better able to assess operational, environmental, and social uncertainties and weigh their potential implications for our strategic priorities.

Our Practices and Priorities

Our values state clearly that sustainability initiatives are fundamental to and firmly rooted in our culture. This top-to-bottom emphasis on the very nature of sustainability helps ensure long-term benefits and value creation, and reflects our commitment to our corporate responsibilities to our shareholders, employees, customers, and society at large.

There are four key areas we believe are central to our Company and to the utility industry as the transition to a sustainable future continues. By looking closely at each area, we have identified practices and priorities that demonstrate our commitment to sustainability in support of our stakeholders while simultaneously illustrating our corporate culture in action.

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Our Objective

As we transform our business to meet the needs of future generations, we are fully committed to the environmental, social and governance priorities that matter most to our shareholders and other stakeholders.

While change creates uncertainty for some, those who arrive prepared at these critical moments find great opportunity for growth and long-term benefits for all. With thoughtful planning, informed decision-making, and an inspired, dedicated workforce, we are well-positioned to capitalize on multiple growth opportunities as our industry continues to evolve and embrace the clean energy transition.

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Corporate Sustainability and Responsibility Report

		To learn more about the actions, projects and initiatives that enhance the sustainability of our Company, our communities, and our planet, our 2023 Corporate Sustainability and Responsibility Report can be viewed in its entirety on our website at 2023 Sustainability Report (unitil.com).   We anticipate issuing our 2024 Corporate Sustainability and Responsibility Report in October 2024, which will provide information about our accomplishments in 2023 and our progress in 2024 in support of our sustainability initiatives and priorities.

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The Board has the following standing committees: Audit Committee; Compensation Committee; Executive Committee; and Nominating and Governance Committee. The tables below provide a summary of each committee with respect to membership and primary responsibilities. 

Audit Committee

NOTES:

Ms. Alonzo joined the Committee on April 26, 2023; Mr. Collin exited the Committee on April 7, 2023.

The Audit Committee is a separately-designated standing audit committee established in accordance with section 3(a)(58)(A) of the Exchange Act. Each member of the Committee is financially literate, knowledgeable and qualified to review financial statements. The Committee operates under a written charter, which it reviews annually, and adopts amendments, if necessary, to reflect changes governing financial reporting and accounting requirements or its responsibilities. The Audit Committee Report, which appears in the section entitled Audit Matters, more fully describes the activities and responsibilities of the Committee.

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Compensation Committee

Committee Members		Neveen F. Awad		Winfield S. Brown		Suzanne Foster		Eben S. Moulton		David A. Whiteley
Independent:		✓		✓		✓		✓		✓
Meetings in 2023:		5		5		5		4		5
Latest Charter Review:		October 31, 2023
Primary Charter Directives:		◾  To establish objectives and interpret the terms of the Company’s compensation policies with regard to base salary, incentive compensation, equity compensation, and benefits programs
		◾  Approval of executive-level base salaries and approval and recommendation to the Board of base salaries for Named Executive Officers
		◾  Review and approval of annual performance measures and approval of annual incentive compensation plan awards
Committee Chair

NOTES:

Mr. Moulton retired from the Board and the Committee on December 1, 2023, and therefore did not attend the last meeting of the year on December 7, 2023.

The Compensation Committee operates under a written charter, which it reviews annually and, as appropriate, amends to reflect changes in its responsibilities. The specific activities and responsibilities of the Committee are described in greater detail in the section entitled Compensation Committee Operations.

Executive Committee

The Executive Committee operates under a written charter, which it reviews annually and, as appropriate, amends to reflect changes in its responsibilities. Committee membership includes the Chairman of the Board, the lead director, and the chairs of the Audit, Compensation, and Nominating and Governance Committees of the Board, as well as any additional Board members appointed at the discretion of the Board.

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Nominating & Governance Committee

Committee Members		Winfield S. Brown		Suzanne Foster		Michael B. Green		David A.  Whiteley
Independent:		✓		✓		✓		✓
Meetings in 2023:		4		4		4		4
Latest Charter Review:		October 31, 2023
Primary Charter Directives:		◾  The review and oversight of corporate governance standards
		◾  To coordinate searches for potential nominees for Board members, review and evaluate qualifications of potential Board members, and recommend to the Board nominees for vacancies occurring from time to time on the Board
		◾  To review Board member performance prior to recommendation for nomination to stand for election to an additional term
		◾  The annual review and evaluation of Directors’ compensation and recommendation of any changes to the Board
Committee Chair

The Nominating and Governance Committee operates under a written charter, which it reviews annually and, as appropriate, amends to reflect changes in its responsibilities.

All Committees

The existence and activities of all committees of the Board do not alter the traditional roles and responsibilities of Unitil’s management. All committees may delegate authority to individuals or subcommittees when they deem appropriate, subject to applicable laws, rules or regulations. However, in delegating authority, a committee shall not be absolved from the responsibilities designated under the terms of its respective charter. All committees shall undertake any other action or exercise such other powers, authority, duties and responsibilities as necessary or appropriate to the discharge of the duties and responsibilities set forth in their respective charters or our Bylaws, or otherwise required by the listing standards of the NYSE or other applicable laws, rules or regulations, or as shall otherwise be determined by or assigned by the Board.

The charters for each of the standing committees are available in the Corporate Governance section of the Investor Relations section of our website at unitil.com/investors, or in print to any shareholder or other interested party, free of charge, upon request to the Office of the Secretary, Unitil Corporation, 6 Liberty Lane West, Hampton, NH 03842-1720; or to InvestorRelations@unitil.com; or by calling toll free 800-999-6501.

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AUDIT COMMITTEE REPORT 

The following report is submitted by the Audit Committee with respect to our audited financial statements for the fiscal year ended December 31, 2023. In discharging its oversight responsibility regarding the audit process, the Audit Committee has discussed with Deloitte & Touche LLP (“Deloitte”), our Company’s independent registered public accounting firm for the fiscal year ended December 31, 2023, the matters required to be discussed by AS 1301, as adopted by the Public Company Accounting Oversight Board. In addition, the Committee has received the written disclosures and the letter from Deloitte required by applicable requirements of the Public Company Accounting Oversight Board regarding Deloitte’s communications with the Committee concerning independence and has discussed with Deloitte the firm’s independence with respect to our Company.

During 2023, the Audit Committee members received quarterly financial information for review and comment prior to the filing of each of our Forms 10-Q with the SEC. In fulfilling its responsibilities relating to the financial statements, the Committee also reviewed and discussed our significant accounting policies and the audited financial statements for the fiscal year ended December 31, 2023, with management and Deloitte. Based on the review and discussions with management and Deloitte, the Committee recommended to the Board that the audited financial statements be included in the 2023 Form 10-K for filing with the SEC.

Audit Committee Members

Anne L. Alonzo, Edward F. Godfrey, Michael B. Green, and Justine Vogel (chair)

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PRINCIPAL ACCOUNTANT FEES & SERVICES

The following table presents fees for professional services rendered by Deloitte, Unitil’s independent registered public accounting firm, for the fiscal years ended December 31, 2023, and December 31, 2022.

Audit Fees

In 2023 and 2022, this category includes fees incurred for professional services rendered by Deloitte for reviewing the quarterly financial statements included in our Quarterly Reports on Form 10-Q, auditing our annual financial statements included in our Annual Report on Form 10-K, and auditing our internal control over financial reporting.

Audit-Related Fees

In 2023, this category includes fees of $22,500 incurred for professional services rendered by Deloitte in connection with our filing of a registration statement with the Securities and Exchange Commission. In 2022, Deloitte did not perform any audit-related services.

Tax Fees

In 2023 and 2022, Deloitte did not perform any tax services.

All Other Fees

In 2023, this category includes fees of $3,790 for cost-based non-audit services consisting of subscriptions to DART (the “Deloitte Accounting Research Tool”). In 2022, Deloitte did not perform any services that are not included in the above categories.

AUDIT COMMITTEE PRE-APPROVAL POLICY

The Audit Committee has a formal policy concerning approval of audit and non-audit services to be provided by the independent registered public accounting firm engaged to audit our consolidated financial statements. The policy requires that all services to be provided by the independent registered public accounting firm, including audit services and permitted audit-related and non-audit services, must be pre-approved by the Committee. The Committee pre-approved all audit, audit-related, tax and all other services provided by Deloitte during fiscal 2023 and 2022.

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COMPENSATION COMMITTEE OPERATIONS

The Compensation Committee is appointed annually by the Board and is responsible for oversight of the executive compensation program. The Committee has overall authority to establish goals and objectives and to interpret the terms of our compensation policies, including base salary, incentive compensation, equity compensation, and all benefits programs. The Committee discharges its oversight responsibilities by carrying out the specific functions and exercising the authority provided in its charter (the “Compensation Committee Charter”). See the section entitled Compensation - Compensation of Named Executive Officers - Compensation of Directors for information on the Nominating and Governance Committee’s work regarding Directors’ compensation.

The Committee has the authority to delegate some of its responsibilities to individuals or subcommittees of the Committee’s choice, subject to applicable laws, rules or regulations. However, such delegation does not absolve the Committee from the responsibilities that it bears under the terms of the Compensation Committee Charter.

The Committee has the authority to invite executive officers, members of management or other guests to attend its meetings, to perform research, or to provide relevant information or recommendations. In 2023, at the Committee’s request, Mr. Meissner, Mr. Hevert, Mr. Hurstak, and the Vice President of People, Shared Services and Organizational Effectiveness served the Committee in a consultative capacity, providing data and analytical support, as well as management perspective and recommendations relative to employee compensation and benefits, including executive compensation.

The Committee also has the authority to retain or obtain the advice of outside counsel, compensation consultants or other advisors to advise the Committee as it deems necessary. The Committee is directly responsible for the appointment, retention terms (including compensation), and oversight of the work of any adviser it retains. Prior to retaining or obtaining advice from an adviser, the Committee will consider factors relevant to the adviser’s independence from management to the extent required by the NYSE listing standards.

The Committee has periodically engaged a compensation consultant, Willis Towers Watson (“Willis Towers”), to provide compensation study data, including data from selected peer companies and compensation marketplace survey analysis, as well as to provide various recommendations based on study findings and industry trends for the Committee’s consideration. Willis Towers is engaged by and reports directly to the Compensation Committee. Willis Towers receives compensation only for services related to executive compensation, employee benefits and general compensation matters, and neither it nor any affiliated company provides any other services to us or our subsidiaries.

The Compensation Committee engaged Willis Towers in 2021 to conduct a competitive assessment of long-term incentive compensation (“LTI”) program design elements and value for senior management. The Committee requested the assessment in order to evaluate our current LTI program with regard to the alignment with competitive market practices for similar utility companies, as well as to analyze the potential separation of long-term and short-term performance incentive metrics. The assessment included a review of general LTI program design features including LTI awards (e.g., restricted stock, restricted stock units and cash), performance metrics, and vesting provisions, as well as senior management benchmarking and a market gap assessment. The Committee continued to further evaluate and develop the LTI program features, process and administration details with the assistance of Willis Towers and management in 2022, and approved a new LTI program in January 2023 with an

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effective date of January 1, 2023. For additional information on the transition of our equity compensation awards under the Second Amended Stock Plan in 2022 and 2023, see the section entitled Elements of Compensation -New Long-Term Equity Incentive Compensation Program of this proxy statement.

See the section entitled Compensation - Compensation Discussion and Analysis for additional information on the comprehensive compensation analysis prepared by Willis Towers in 2019 and the Committee’s work regarding compensation-related matters for the 2020, 2021, 2022 and 2023 compensation years.

In 2023, we incurred total expenses of $41,000 for services rendered by Willis Towers. The services were approved by the Compensation Committee as part of the Willis Towers 2023 engagement.

In addition, we requested and received information from Willis Towers to assist the Committee in determining whether its work raised any conflict of interest. Based on the responses provided by Willis Towers in its completed Conflict of Interest Questionnaire, there were no conflicts of interest in 2023.

COMPENSATION COMMITTEE INTERLOCKS & INSIDER PARTICIPATION

The current members of the Compensation Committee are not current or former officers or employees of Unitil. No member of the Committee has any relationship requiring disclosure under Item 404 of Regulation S-K, Transactions with Related Persons. In addition, none of our executive officers serve on the board of directors or compensation committee of another company where an executive officer of the other company also serves on the Board or Compensation Committee.

RISK & BROAD-BASED COMPENSATION PROGRAMS

We believe the risks that may arise from our compensation policies and practices, which include the annual short-term incentive award performance metrics, long-term incentive award performance metrics, variable and non-variable pay mix, and limited non-performance payouts, are not likely to have a material adverse effect on us because of multiple factors that work together, as summarized below.

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COMPENSATION DISCUSSION & ANALYSIS

2023 PERFORMANCE REVIEW

As a Company, 2023 was a challenging year. We entered the year with soaring electricity prices, continuing post-pandemic economic distortion, stubbornly high inflation, interest rate instability, energy supply volatility, and many other obstacles. Despite the challenges, at year end, we achieved record earnings of $2.82 per share, a 9% increase over 2022, and a Net Income increase to $45.2 million. This marks the third consecutive year that we delivered earnings growth greater than the high end of our 5% - 7% guidance in a challenging macro environment. Further, and equally important, we continued to build a strong foundation for sustained growth in the years ahead. Our robust investment plan will support continued modernization of our electric and gas infrastructure while advancing state climate policies and the clean energy transition.   Our strong financial results in 2023 were supported by a multitude of noteworthy accomplishments in the past year. These accomplishments are a testament to our resiliency and commitment to continued execution of the fundamentals of our business for continued success in the years ahead. A summary of some of these successes is below.

Operations and Safety

Customer Service

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Employee Satisfaction and Culture

Infrastructure Investments

Regulation

Sustainability / Carbon Reduction Commitment

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In addition to the operational successes noted above, we also continued to advance our long-term strategic planning initiatives, specifically in the areas of customer engagement, clean transportation, renewable energy, grid modernization, and diversity, equity and inclusion. We continued to accelerate dividend growth for our investors continuing our unbroken record of annual dividend payments in 2023. On January 25, 2023, the Board of Directors approved an increase in the annualized dividend to $1.62 per share, lowering our dividend payout ratio to 57%, near the low end of our long-term target range of 55% - 65%. On January 31, 2024, the Board of Directors voted to increase the 2024 annualized dividend to $1.70 per share. Additionally, we were one of the few utilities to produce a positive shareholder return in 2023, with the UTY and S&P Utilities indexes both down over 10%.

EXECUTIVE COMPENSATION POLICIES

EXECUTIVE COMPENSATION RECOVERY POLICY

The purpose of the Executive Compensation Recovery Policy (the “Policy”) is to provide for the recovery of certain executive compensation in the event of an accounting restatement resulting from material noncompliance with financial reporting requirements under the securities laws. In the event we are required to prepare an accounting restatement of our financial statements due to material non-compliance with any financial reporting requirement, we shall be entitled to recover any excess performance-based compensation received by any current or former Covered Executive⁴ during the three-year period immediately preceding the date on which we are required to prepare an accounting restatement. “Performance-based compensation⁵” is defined as all annual incentives and long-term incentives (whether in cash, in equity, or otherwise) granted, earned, vested or unvested with performance features based wholly or in part on our Company’s or a specified group’s attainment of a financial reporting measure. “Financial reporting measures” is defined as measures that are determined and presented in accordance with the accounting principles used in preparing our financial statements, and any measure(s) that are derived wholly or in part from these measures. We shall recover any erroneously awarded performance-based compensation in accordance with the Policy, with the exception that if the conditions of Rule 10D-1 of the Exchange Act and the listing standards of the NYSE are met, the Compensation Committee determines that recovery would be impractical. All actions taken under this Policy will comply with Section 10D of the Exchange Act and the listing standards of the NYSE.

EXECUTIVE STOCK OWNERSHIP POLICY

Executive Officer will have four years from the date of appointment to obtain the required shares of stock. Additional information concerning the current share ownership of our Directors and officers can be found in the section entitled Share Ownership —Beneficial Ownership.

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EXECUTIVE STOCK RETENTION POLICY

The Board believes that our executive officers should own a significant number of shares of our common stock to properly align their interests with those of our shareholders. All Named Executive Officers are required to hold all forms of equity received as compensation until retirement or other separation from the Company. The Board, in its sole discretion, may approve a waiver to this policy as circumstances may warrant. To date, no such waivers have been proposed or approved.

PROHIBITION ON HEDGING AND/OR PLEDGING COMPANY STOCK POLICY

All members of the Board and the executive officers are prohibited from engaging in short sales or engaging in any hedging transaction with respect to Unitil common stock, as well as engaging in any transactions that result in pledging, or using as collateral, shares of Unitil common stock in order to secure personal loans or other obligations, including any shares that may be held in a margin account.

Compensation Philosophy and Administration

The Compensation Committee is responsible for oversight of our executive compensation program. The Committee, the Board and the Company recognize the value and importance of sound principles for the development and administration of competitive compensation and benefit programs. We believe our executive compensation program:

The Compensation Committee uses a set of guiding principles in the design and implementation of the Company’s executive compensation program, which are outlined above. The primary goal of the guiding principles is to ensure consistency and fairness in all aspects of the Committee’s oversight of compensation policy. Additional information concerning the processes and operational procedures followed by the Committee can be found in the section entitled Compensation—Compensation Committee Operations.

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Compensation Policy & Process

The principal objective of our executive compensation program is to attract, motivate, retain and reward highly qualified employees committed to the achievement of solid financial performance, outstanding service to customers, and excellence in the management of our assets. It is our belief that a strong sense of teamwork and shared responsibility are vital to achieving strong performance. Our incentive compensation reflects and supports this philosophy with an appropriate balance of financial and operational goals that apply to the entire management team. See the section entitled Compensation - Compensation Discussion and Analysis - Elements of Compensation for a discussion of the specific goals set, and results achieved, for 2023. We also believe that retention of talented and dedicated key executives will help ensure continued focus on the achievement of long-term growth in shareholder value and overall sustainability, which in turn will provide significant benefits to all of our stakeholders, including shareholders, customers and employees.

Compensation Policy – What We Do & What We Do Not Do

The Compensation Committee continuously strives to make improvements to our executive compensation policies. Below is a summary of what we do and what we do not do with respect to executive compensation, the totality of which the Committee and the Board believe aligns with the long-term interests of our shareholders as well as with today’s commonly accepted best practices in the market.

* The Committee defines “annual compensation” in its Guiding Principles as “base salary, cash incentive and equity compensation.”

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Compensation Decisions for 2021 - 2023

In order to prudently manage outside consulting expenses, and in particular during the COVID-19 pandemic years, the Compensation Committee decided to forego consulting work related to overall executive pay in the years 2020, 2021 and 2022. Instead, the Committee determined the information contained in the comprehensive 2019 Compensation Analysis remained relevant and therefore was used as an across-the-board assessment benchmark. The Committee also used existing compensation programs and policies previously found to be reasonable and competitive to evaluate executive compensation for 2021, 2022 and 2023. The Committee approved executive compensation paid in January of each respective year as noted. We continue to include the details of the 2019 Compensation Analysis, which is described below, as it is the base benchmark for executive compensation disclosed in this proxy statement.

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2019 Compensation Analysis - Summary

The 2019 Compensation Analysis scope included an overall analysis of our compensation as it relates to and supports our business strategy, alignment with the compensation philosophy, peer group identification, detailed information on executive, non-union staff and Directors’ compensation, as well as a review of the research methodology and process, key findings with regard to base salary and incentive compensation, program assessment, and several recommendations for the Committee’s consideration.

General Methodology

Towers Watson used both compensation data from published compensation surveys focused on comparably sized organizations in the utility sector and general industry sector (for “cross industry” positions), and compensation data from proxy filings of our approved peer group of 13 publicly traded utility companies with annual revenues between $275 million and $1.6 billion (the “2019 Peer Group”)⁶, which was approved by the Compensation Committee in April 2019 for the purposes of this Analysis.

Compensation Data from Published Compensation Surveys

Compensation data from published compensation surveys focused on comparably sized organizations in the utility sector and general industry sector (for “cross industry” positions)⁷. Published survey data were size-adjusted based on revenue, employee regression and/or scope parameters. Because the surveys are confidential, the specific data selected by Willis Towers did not indicate survey participants by company name.

Compensation Data from Proxy Filings

Compensation data was also extracted from the 2019 Peer Group proxy filings. The Compensation Committee used this data to analyze only the CEO’s and CFO’s compensation, with the objective of ensuring that CEO and CFO total compensation was reasonable, competitive and consistent with pay practices at peer companies.

Published compensation surveys generally provide a broader sample of data upon which to base compensation decisions, which is essential when analyzing a large number of positions as was the case with the 2019 Compensation Analysis. Data from peer company proxy filings generally validate published survey information with definitive executive compensation data from specific companies.

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Methodology: Peer Group Proxy Filings

Willis Towers completed the 2019 Compensation Analysis in July 2019, and provided a comprehensive report outlining the findings of the Analysis and associated recommendations to the Committee for review and consideration.

The 2019 Compensation Analysis allowed the Committee to gain a greater understanding of then current compensation in the context of market practices, establish a benchmark upon which to base its compensation decisions for compensation years 2020 through 2023, and accurately assess the competitiveness of each executive officer’s, including the CEO’s and CFO’s, overall compensation and alignment with the Committee’s Compensation Philosophy. It is anticipated that the Committee will use the 2019 Compensation Analysis as a baseline study, with periodic updates as needed, until the next comprehensive analysis is prepared, which we anticipate will occur in 2024.

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Evaluation of Base Salary and Incentive Compensation:

President and Chief Administrative Officer Position

As part of our ongoing management succession planning process, in early 2023, the Board decided to split the positions of chief executive officer and president to address the May 1, 2023, planned retirement of Todd R. Black as senior vice president of external affairs and customer relations, and to provide opportunities for advancement and development of existing members of senior management. Effective on May 1, 2023, Robert B. Hevert (formerly senior vice president, chief financial officer and treasurer) was promoted to the newly created position of president and chief administrative officer with expanded responsibilities for external affairs and customers relations. Mr. Hevert’s promotion also set into motion additional senior management promotions, including, among others, Daniel J. Hurstak (formerly controller and chief accounting officer) being promoted to senior vice president, chief financial officer and treasurer. Mr. Meissner relinquished the position of president, but retained the positions of chairman of the board and chief executive officer.

In the spring of 2023, we initiated our salary administration process (described in detail below), and engaged Willis Towers to review and evaluate the duties and accountabilities outlined in the job description of president and chief administrative officer and gather competitive market compensation data. The purpose of the engagement of Willis Towers was to ensure Mr. Hevert was appropriately and fairly compensated in his new role for which we had no previous references or benchmarks from a past compensation analysis or related study. Willis Towers utilized executive compensation databases to conduct a comprehensive compensation review for this new executive officer position. Specifically, Willis Towers utilized data from its Energy Services Executive Compensation surveys and its General Industry Executive Compensation surveys to compile an appropriate compensation recommendation. The data provided by Willis Towers was tiered at the 25^th, 50^th and 75^th percentiles. In keeping with our compensation guiding principles to pay employees at the median of the market, the Compensation Committee approved base salary, short-term incentive compensation and long-term incentive compensation target opportunity levels that approximated the 50^th percentile of the market compensation data reviewed. For additional information on Mr. Hevert’s 2023 compensation, please see the section entitled Compensation of Named Executive Officers of this proxy statement.

Salary Administration

Our Salary Administration Policy has three objectives:

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The Salary Administration Policy includes three important components:

Job Description Every employee of the Company has a job description that represents his or her position within the Company. All job descriptions are written using a requisite format describing the position purpose, principal accountabilities, competencies, challenges, decision-making authority, qualifications, and scope and quantitative dimensions.   Job Evaluation We use a variety of published salary sources and survey data to assist in the review and evaluation of non-executive, non-union job descriptions in order to confirm reasonable and appropriate base compensation for each position. See also the section entitled Compensation - Base Salary below. This practice provides for internal equity between comparable positions as well as external comparability with other companies. The end result of the job evaluation process is that each job is assigned a pay grade that translates into a salary range. Executive level positions (including the Named Executive Officers) are reviewed and evaluated independently by Willis Towers.
Market Analysis & Salary Range We participate in numerous salary market studies to ensure that the competitiveness of base salaries is maintained. We adjust the salary ranges each year based upon the results of these surveys to ensure that we maintain our salary ranges at the median market level. Historically, the salary ranges have been adjusted by approximately 2 - 4 % annually based on market survey data. The midpoint of the base salary range is set at the median level of the broad-based published compensation survey group when compared to similar positions at comparable companies. The minimum in the salary range is determined by multiplying the midpoint by 80%, and the maximum is determined by multiplying the midpoint by 120%. In general, the salary range minimum is commonly the lowest amount we will pay a new employee in the job, with the aim of employees reaching the midpoint of the range within five years. The midpoint is where we strive to pay fully trained, fully competent employees. The midpoint to maximum range is where high-performing employees and long-term employees tend to be paid. Exceptions are occasionally made based on experience, skills, education, and other factors.

Base Salary

We set base salary ranges for every job grade and position based upon salary survey data provided by Willis Towers and in accordance with the Salary Administration Policy described above. In relation to each Named Executive Officer, base salary is set within the salary range based upon individual experience, skills, and education, as well as performance relative to individual annual goals. This process is used for both executive and non-executive positions.

Short-Term Incentive Compensation – Cash Incentive

We set annual target cash incentive awards equal to the median of the broad-based published compensation survey group for the executive officers’ target cash incentive awards at other comparable companies based on data provided by Willis Towers. The Committee also used information from the proxy statements of our peer group, at the 25^th percentile target, as a secondary source to set the CEO’s and

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CFO’s annual target cash incentive award. We have developed a “balanced score card” approach to setting goals for the annual incentive awards, which includes certain goals from the Strategic Plan that represent success in financial results, electric reliability, gas safety, customer service and distribution cost per customer. The Compensation Committee approves the quantitative goals, also referred to as performance metrics, for these awards annually. See the section entitled Compensation -Compensation Discussion and Analysis— Elements of Compensation for a discussion of the balanced score card.

Long-Term Incentive Compensation – Equity Compensation

We grant shares of restricted stock to selected management participants in the Second Amended Stock Plan generally on an annual basis. The size of the annual restricted stock award (the “target award”) is based upon the midpoint of the participant’s salary grade, multiplied by the participant’s salary grade multiplier, ( i.e., the equity compensation opportunity percentage), divided by the 30-day average stock price of our common stock,⁸ less the percentage of anticipated Federal and Medicare taxes to equal the number of shares to be granted. The salary grade multiplier is based on research data provided by Willis Towers in their competitive assessment (the “Assessment”) of long-term incentive compensation (“LTI”) program design conducted in 2022. Willis Towers incorporated information from the proxy statements of our peer group into the Assessment as a benchmark to set the salary grade multiplier. For additional information on the Willis Towers Assessment of LTI program design, see the section entitled Compensation Committee Operations in this proxy statement.

All Named Executive Officers are required to hold all forms of equity, vested or unvested, received as compensation until retirement or other separation from Unitil. The Board, in its sole discretion, may approve a waiver to this policy as circumstances may warrant. However, to date, no such waiver has been requested or granted.

Performance-Related Incentive Compensation

In addition to individual performance, overall Company performance is a critical component in the determination of how each individual executive is paid relative to the market median of the broad-based published compensation survey group, as described above. See also the section entitled Compensation – Compensation of Named Executive Officers– Proportional Compensation for additional information on performance-related compensation.

CEO Pay Ratio

Summary

As required by the Dodd-Frank Wall Street Reform and Consumer Protection Act of 2010 (the “Dodd-Frank Act”), the Securities and Exchange Commission adopted a rule requiring annual disclosure of the ratio of the median employee’s annual total compensation to the total annual compensation of the principal executive officer. Our principal executive officer is Mr. Meissner (the “CEO”).

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We believe the compensation program and salary administration policy should be consistent and internally equitable to motivate all employees to perform in ways that enhance shareholder value. We also believe that our compensation philosophy and processes yield an equitable result for all employees, which is reflected in the resulting ratio.

Methodology

To reasonably identify the median employee, we prepared a list of all active employees (excluding the CEO) as of December 31, 2023. The list included part-time employees. As of December 31, 2023, we employed 531 people of which 349 were non-union employees and 182 were union employees covered by a collective bargaining agreement.

Next, we extracted the taxable wages number reported in Box 1 of the 2023 Form W-2 from our payroll records for each employee, excluding the CEO. We did not annualize wages and salaries for those employees who were not employed for the full year of 2023. The median employee was then identified based on taxable wages as reported on Form W-2. Once identified, we calculated the median employee’s total annual compensation in the same manner as “Total Compensation” shown for the CEO in the Summary Compensation Table in the section entitled Compensation – Compensation of Named Executive Officers.

Results

The table below shows the information used for the calculation of the ratio of the estimated annual total compensation of the median employee identified using the methodology described above to the annual total compensation of Mr. Meissner as calculated for the Summary Compensation Table.

NOTES:

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Shareholder Advisory Vote on Executive Compensation

As required by the Dodd-Frank Act, we must provide the opportunity for shareholders to vote, on an advisory basis, on the compensation of executives (commonly known as a “say-on-pay” proposal). We present the say-on-pay proposal to our shareholders annually.

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ELEMENTS OF COMPENSATION

Base Salary

Every employee is paid a base salary. The purpose of base salary is to reward employees for the expertise and value they bring to their jobs. Base salary is determined according to our salary policy, which assigns each position a grade and a corresponding salary range. We set salary ranges for every position based upon comparative salary data provided by Willis Towers. The midpoint of the salary range is set at the median level of the broad-based published compensation survey group when compared to similar positions at comparable companies. The minimum parameter in the salary range is determined by multiplying the midpoint by 80%, and the maximum parameter is determined by multiplying the midpoint by 120%. The salary range is then used to manage each employee’s salary, which is based on merit, within the range. For each employee (including Named Executive Officers), base salary is set within the salary range based upon individual performance relative to individual annual goals. The elements of individual performance differ depending on the individual position, but generally include: quality of work; successful completion of established goals; ability to initiate creative solutions; adaptability to change; and impact on our overall performance. The salaries of all employees (including the Named Executive Officers) are reviewed annually, as well as at the time of a promotion or change in responsibilities.

increases also include evaluation of overall Company performance for the year. Merit increases are generally effective as of January 1 of each year. Merit increases also are one of the methods used to reach one of our competitive compensation guiding principles, which is to ensure that employees are paid at or near the market median of the broad-based published compensation survey group. Merit increases may also be adjusted by the Compensation Committee to reflect the market value of a job when compared to similar positions at other companies within our peer group, as recommended by Willis Towers.

The process followed to determine base salary increases for the Named Executive Officers begins with an annual summary and evaluation of Unitil’s overall performance provided to the Board by the CEO, which generally occurs in mid-January. The Compensation Committee and the Executive Committee meet jointly in executive session to discuss the evaluation of our overall performance, as well as to discuss the CEO’s performance in relation to our performance for the year, considering both the quantitative and qualitative aspects of the performance of both the CEO and our Company as a whole. The Compensation Committee uses the feedback gained in the joint meeting along with the market competitive salary information previously described to determine an appropriate base salary increase for the CEO based on both merit and

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market conditions. The CEO provides a recommendation to the Compensation Committee for base salary increases for the other Named Executive Officers. The Compensation Committee then reviews and recommends the base salaries of all of the Named Executive Officers to the full Board for discussion and approval. The Committee’s recommendations are based on the performance evaluations and market information for each of the Named Executive Officers. Each Named Executive Officer received the base salary increase percentage from 2022 to 2023 as noted in the table above. Mr. Hevert and Mr. Hurstak were promoted to President and Chief Administrative Officer and to Senior Vice President, Chief Financial Officer and Treasurer, respectively, on May 1, 2023, and the increase in base salary resulting from those promotions is reflected in the percentages noted above. Mr. Black retired on May 1, 2023, and the negative percentage increase shown reflects a partial base salary paid in 2023.

Incentive Compensation

Management Incentive Plan

The Unitil Corporation Management Incentive Plan (the “Management Incentive Plan”) provides annual cash incentive payments based upon the attainment of specified goals selected from the Strategic Plan. The Compensation Committee selects participants in the plan and establishes their individual target awards. All executives (including the Named Executive Officers) are participants in the Management Incentive Plan. The purpose of the Management Incentive Plan, which is consistent with our principal compensation objective, is to provide executives with significant incentives related to performance, thereby providing motivation to maximize efforts on behalf of all of our stakeholders. The Management Incentive Plan is further intended to provide executives with competitive target levels of total compensation when considered with base salaries.

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Actual awards may be less than or greater than the target awards depending upon final results achieved. In addition, the Committee has the authority to increase or decrease the annual cash incentive award under the Management Incentive Plan when the final results calculation does not properly balance the interests of employees and shareholders. The Committee also has the sole discretion to pay no award when one would otherwise be paid. The Committee has in the past exercised its discretion to both increase and decrease award payments but did not exercise its discretion in connection with the awards for 2023 results.

Second Amended and Restated 2003 Stock Plan 

The Unitil Corporation Second Amended and Restated 2003 Stock Plan (as amended, the “Second Amended Stock Plan”) was initially approved by shareholders at the 2003 annual meeting of shareholders, amended and restated on March 24, 2011, and again amended and restated, effective April 19, 2012. Participation in the Second Amended Stock Plan is currently limited to Directors, executive officers and other employees and consultants selected by the Compensation Committee. Common stock, restricted stock and restricted stock units (“RSUs”) may be issued to participants in the Second Amended Stock Plan. The

The Committee feels that equity-based compensation ensures that executive officers have a continuing stake in our long-term success. Executive officers are subject to both stringent stock ownership requirements as well as a retention requirement which stipulates that all forms of equity received as compensation be held until retirement or other separation from the Company. The Committee believes that the retention requirement provides an additional element of incentive to increase shareholder value over the long term. The details of the stock ownership and retention requirements are discussed in greater detail below.

New Long-Term Equity Incentive Compensation Program

On January 24, 2023, the Compensation Committee approved a new long-term equity incentive compensation program (the “New LTIP”) that is applicable to the grant of restricted stock awards to the Named Executive Officers and other senior management participants (collectively, the “Participants”).

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Time Restricted Shares

Time Restricted Shares generally vest over a period of four years at a rate of 25% each year. Prior to the end of the vesting period, Time Restricted Shares are subject to forfeiture if the Participant’s employment terminates other than due to death, disability or retirement. During the vesting period, dividends on Time Restricted Shares are paid to the Participants.

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Performance Restricted Shares

Performance Restricted Shares generally vest after a performance period of three years based on the attainment of certain performance thresholds of certain defined performance metrics, each as set by the Compensation Committee at the beginning of the performance period. On January 24, 2023, the Compensation Committee selected two performance metrics for the three-year performance period starting January 1, 2023 through December 31, 2025:

Performance Restricted Shares are generally granted at target at the beginning of the performance period.

Summary of Time Restricted Shares and Performance Restricted Shares

The following table summarizes certain terms of the Time Restricted Shares and the Performance Restricted Shares.