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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 14A
(Rule 14a-101)

INFORMATION REQUIRED IN
PROXY STATEMENT

SCHEDULE 14A INFORMATION

Proxy Statement Pursuant to Section 14(a) of
the Securities Exchange Act of 1934 (Amendment No.          )

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March 24, 201528, 2017

Dear Fellow Shareholders of ACNB Corporation:

        On behalf of the Board of Directors, I am pleased to invite you to attend our Annual Meeting of Shareholders to be held on Tuesday, May 5, 2015,2, 2017, at 1:00 p.m., prevailing time, at the ACNB Corporation Operations Center, 100 V-Twin Drive, Gettysburg, Pennsylvania 17325. At the annual meeting, you will have the opportunity to ask questions and to make comments. Enclosed with the proxy statement is the notice of meeting, proxy card, ACNB Corporation's 20142016 Annual Review, and ACNB Corporation's 20142016 Annual Report on Form 10-K.

        The principal business of the meeting is to fix the number of Directors of ACNB Corporation at thirteen (13)sixteen (16); to fix the number of Class 1 Directors at five (5)six (6); to fix the number of Class 2 Directors at four (4)six (6); to fix the number of Class 3 Directors at four (4); to elect four (4) Class 23 Directors to serve for terms of three (3) years and until their successors are elected and qualified; to elect one (1) Class 2 Director to serve for a term of one (1) year and until his successor is elected and qualified; to conduct a non-binding vote on executive compensation; to conduct a non-binding vote on the frequency of non-binding shareholder votes on executive compensation; to ratify the selection of BDO USA, LLP as ACNB Corporation's independent registered public accounting firm; and, to transact any other business that is properly presented at the annual meeting. The notice of meeting and proxy statement accompanying this letter describe the specific business to be acted upon in more detail.

        Whether or not you plan to attend the annual meeting, I urge you to vote as soon as possible by completing, signing and returning the enclosed proxy card in the envelope provided or to vote via the internet or telephone. Your prompt vote will save the Corporation expenses involved in further communications. Your vote is important. Voting by written proxy, internet or telephone will ensure your representation at the annual meeting if you do not attend in person.

        I look forward to seeing you on May 5, 2015,2, 2017, at the Corporation's annual meeting.

Sincerely,

Thomas A. Ritter
President & Chief Executive Officer

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ACNB CORPORATION

NASDAQ TRADING SYMBOL: ACNB

acnb.com

NOTICE OF ANNUAL MEETING OF SHAREHOLDERS

AND

PROXY STATEMENT

20152017

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Proxy Statement

Dated and to be mailed to shareholders on or about March 24, 2015.28, 2017.

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ACNB CORPORATION
16 LINCOLN SQUARE
P.O. BOX 3129
GETTYSBURG, PENNSYLVANIA 17325
(717) 334-3161

NOTICE OF ANNUAL MEETING OF SHAREHOLDERS
TO BE HELD ON MAY 5, 20152, 2017

TO THE SHAREHOLDERS OF ACNB CORPORATION:

        NOTICE IS HEREBY GIVEN that the Annual Meeting of Shareholders of ACNB Corporation will be held at the ACNB Corporation Operations Center, 100 V-Twin Drive, Gettysburg, Pennsylvania 17325 on Tuesday, May 5, 2015,2, 2017, at 1:00 p.m., prevailing time, for the purpose of considering and voting upon the following matters:

1.

To fix the number of Directors of ACNB Corporation at thirteen (13)sixteen (16);



2.

To fix the number of Class 1 Directors at five (5)six (6);



3.

To fix the number of Class 2 Directors at four (4)six (6);



4.

To fix the number of Class 3 Directors at four (4);



5.

To elect four (4) Class 23 Directors to serve for terms of three (3) years and until their successors are elected and qualified;



6.

To elect one (1) Class 2 Director to serve for a term of one (1) year and until his successor is elected and qualified;



7.

To conduct a non-binding vote on executive compensation;



7.8.

To conduct a non-binding vote on the frequency of non-binding shareholder votes on executive compensation;



9.

To ratify the selection of BDO USA, LLP as ACNB Corporation's independent registered public accounting firm; and,



8.10.

To transact such other business as may properly come before the 20152017 Annual Meeting and any adjournment or postponement thereof.

        Only those shareholders of record, at the close of business on March 10, 2015,13, 2017, are entitled to notice of and to vote at the meeting.

        Please promptly sign the enclosed proxy card and return it in the enclosed postage-paid envelope or vote by internet or telephone. We cordially invite you to attend the meeting. Your proxy is revocable and you may withdraw it at any time prior to it being voted. You may deliver notice of revocation or deliver a later dated proxy to the Secretary of the Corporation before the vote at the meeting.

        The Corporation's Board of Directors is distributing the proxy statement, proxy card, ACNB Corporation's 20142016 Annual Review, and ACNB Corporation's 20142016 Annual Report on Form 10-K on or about March 24, 2015.28, 2017.

		BY ORDER OF THE BOARD OF DIRECTORS,
		Thomas A. Ritter President & Chief Executive Officer

Gettysburg, Pennsylvania
March 24, 201528, 2017

YOUR VOTE IS IMPORTANT.
PLEASE COMPLETE, SIGN, DATE AND RETURNVOTE YOUR PROXY CARD.TODAY.

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PROXY STATEMENT

GENERAL INFORMATION

Date, Time and Place of the Annual Meeting

        ACNB Corporation, a Pennsylvania business corporation and registered financial holding company, furnishes this proxy statement in connection with the solicitation by the Board of Directors of proxies to be voted at the Corporation's Annual Meeting of Shareholders. The Annual Meeting of Shareholders will be held on Tuesday, May 5, 2015,2, 2017, at 1:00 p.m., prevailing time, at the ACNB Corporation Operations Center, 100 V-Twin Drive, Gettysburg, Pennsylvania 17325. Included with this proxy statement is a copy of ACNB Corporation's 20142016 Annual Review and ACNB Corporation's 20142016 Annual Report on Form 10-K for the fiscal year ended December 31, 2014.2016.

        The Corporation's principal executive office is located at 16 Lincoln Square, Gettysburg, Pennsylvania 17325. The Corporation's telephone number is (717) 334-3161. All inquiries regarding the annual meeting should be directed to Lynda L. Glass, Executive Vice President, President/Secretary & Chief Governance Officer of ACNB Corporation, at (717) 339-5085.

Description of ACNB Corporation

        ACNB Corporation was formed in 1982 and became the holding company for the banking subsidiary in 1983. ACNB Corporation's wholly-owned banking subsidiary is ACNB Bank, a Pennsylvania state-chartered bank and trust company, formerly Adams County National Bank. The Corporation's primary activity consists of owning and supervising its banking subsidiary.

        The Corporation also owns and supervises Russell Insurance Group, Inc. as its insurance subsidiary.

        We have not authorized anyone to provide you with information about the Corporation; therefore, you should rely only on the information contained in this document or on documents to which we refer you. Although we believe we have provided you with all the information helpful to you in your decision to vote, events may occur at ACNB Corporation subsequent to printing this proxy statement that might affect your decision or the value of your stock.

Internet Availability of Proxy Materials

        Important Notice Regarding the Availability of Proxy Materials for the Shareholder Meeting to Be Held on May 5, 2015.2, 2017. The notice of meeting, proxy statement, proxy card, ACNB Corporation's 20142016 Annual Review, and ACNB Corporation's 20142016 Annual Report on Form 10-K are available atacnb.com under the Investor Relations/ACNB Corporation tab or directly athttp:https://www.acnb.com/acnb-corporation.

VOTING PROCEDURES

Solicitation and Voting of Proxies

        The Board of Directors solicits this proxy for use at the Corporation's 20152017 Annual Meeting of Shareholders. The Corporation's directors and officers and ACNB Bank employees may solicit proxies in person or by telephone, facsimile, email or other similar electronic means without additional compensation. The Corporation will pay the cost of preparing, assembling, printing, mailing and soliciting proxies and any additional material that the Corporation sends to its shareholders. The Corporation will make arrangements with brokerage firms and other custodians, nominees and fiduciaries to forward proxy solicitation materials to the beneficial owners of stock held by these entities, as well as will reimburse these third parties for their reasonable forwarding expenses. This proxy statement and the related proxy card are being distributed on or about March 24, 2015.28, 2017.

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        Shareholders of record at the close of business on March 10, 201513, 2017 (the annual meeting record date), are entitled to vote at the meeting. The Corporation's records show that, as of the annual meeting record date, 6,015,6506,064,138 shares of the Corporation's common stock, par value $2.50 per share, were outstanding. On all matters to come before the annual meeting, shareholders may cast one (1) vote for each share held. Cumulative voting rights do not exist with respect to the election of directors.

        You may vote your shares by completing and returning a written proxy card or voting by internet or telephone. You may also vote in person at the meeting. Submitting your voting instructions by returning a proxy card, internet or telephone will not affect your right to attend the meeting and vote, if you later decide to attend in person. If your shares are registered directly in your name with ACNB Corporation's transfer agent, Computershare, you are considered, with respect to those shares, the shareholder of record, and these proxy materials are being sent directly to you by the Corporation. As the shareholder of record, you have the right to grant your voting proxy directly to the proxyholders or to vote in person at the meeting. The Corporation has enclosed a proxy card, as well as instructions to vote by internet or telephone, for your use.

        If your shares are held in a stock brokerage account or by a bank or other nominee, you are considered the beneficial owner of shares held in street name, and these proxy materials are being forwarded to you by your broker or nominee which is considered, with respect to those shares, the shareholder of record. As the beneficial owner, you have the right to direct your broker or nominee how to vote and you are also invited to attend the meeting. However, because you are not the shareholder of record, you may not vote your street name shares in person at the meeting, unless you obtain a proxy executed in your favor from the holder of record. Your broker or nominee has enclosed a voting instruction card for you to use in directing the broker or nominee how to vote your shares.

        By properly completing a proxy, you appoint James J. Emmett PattersonLott and Marian B. Schultz as proxyholders to vote your shares, as indicated on the proxy card. Any signed proxy card or vote by internet or telephone not specifying to the contrary will be votedFOR:

1.

Fixing the number of Directors of ACNB Corporation at thirteen (13)sixteen (16);



2.

Fixing the number of Class 1 Directors at five (5)six (6);



3.

Fixing the number of Class 2 Directors at four (4)six (6);



4.

Fixing the number of Class 3 Directors at four (4);



5.

Electing four (4) Class 23 Directors to serve for terms of three (3) years and until their successors are elected and qualified;



6.

Electing one (1) Class 2 Director to serve for a term of one (1) year and until his successor is elected and qualified;



7.

Approving the non-binding vote on executive compensation;



8.

Approving the non-binding vote on the frequency of non-binding shareholder votes on executive compensation for one (1) year; and,



7.9.

Ratifying the selection of BDO USA, LLP as ACNB Corporation's independent registered public accounting firm.

        You may revoke your written proxy by delivering written notice of revocation to Lynda L. Glass, Executive Vice President, President/Secretary & Chief Governance Officer of the Corporation, by executing a later dated proxy and giving written notice of the revocation to Ms. Glass or voting again by internet or telephone at any time before the proxy is voted at the meeting. Proxyholders will vote shares

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represented by proxies on the accompanying proxy card, if properly signed and returned, or by internet or telephone in accordance with instructions offrom shareholders.

        Although the Board of Directors knows of no other business to be presented, in the event that any other matters are properly brought before the meeting, any proxy given pursuant to this solicitation will be voted in accordance with the recommendations of the Board of Directors. This proxy statement is being mailed to the Corporation's shareholders on or about March 24, 2015.

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Quorum and Vote Required for Approval

        As of the close of business on March 10, 2015,13, 2017, the Corporation had 6,015,6506,064,138 shares of common stock, par value $2.50 per share, outstanding.

        Under Pennsylvania law and ACNB Corporation's Bylaws, the presence of a quorum is required for each matter to be acted upon at the meeting. A majority of the outstanding shares of common stock, represented in person or by proxy, constitutes a quorum. Votes withheld and abstentions are counted in determining the presence of a quorum for a particular matter. Broker non-votes are not counted in determining the presence of a quorum for a particular matter as to which the broker withheld authority. Each share is entitled to one (1) vote on all matters submitted to a vote of the shareholders. All matters to be voted upon by the shareholders require the affirmative vote of a majority of shares voted, in person or by proxy, at the annual meeting, except in cases where the vote of a greater number of shares is required by law or under ACNB Corporation's Articles of Incorporation or Bylaws. In the case of the election of directors, the candidates receiving the highest number of votes are elected. Shareholders are not entitled to cumulate votes for the election of directors.

        If a quorum is present, fixing the number of directors of the Board of Directors, fixing the number of directors in each class, approving the non-binding proposal on executive compensation, and ratifying the independent registered public accounting firm for the year ending December 31, 2015,2017, requires the affirmative"FOR" vote of a majority of all votes cast, in person or by proxy. Abstentions and broker non-votes are not deemed to constitute "votes cast" and, therefore, do not count either for or against the proposals. Abstentions and broker non-votes, however, have the practical effect of reducing the number of affirmative votes required to achieve a majority for the matter by reducing the total number of shares voted from which the required majority is calculated.

        If a quorum is present, the shareholders will elect the nominees for director receiving the highest number of"FOR" votes cast by those shareholders entitled to vote for the election of directors. Shareholders will approve the frequency of the non-binding vote on executive compensation by a plurality of votes cast on the matter. The proxyholders will not cast votes for or against any director nominees whereor for any specific year frequency when the broker withheld authority.

GOVERNANCE OF THE CORPORATION

        Our Board of Directors believes that the purpose of corporate governance is to ensure that we maximize shareholder value in a manner consistent with legal requirements and the highest standards of integrity. The Board has adopted and adheres to corporate governance practices which the Board and executive management believe promote this purpose, are sound, and represent best practices. We continually review these governance practices, Pennsylvania law (the state in which we are incorporated), rules and listing standards of The Nasdaq Stock Market, SEC regulations, as well as best practices suggested by recognized governance authorities. Currently, our Board of Directors has thirteen (13) members. Pursuant to the Corporation's mandatory retirement requirements, Harry L. Wheeler will retire at the annual meeting. Under the SEC and Nasdaq standards for independence, all non-employee directors and nominees meet the standards for independence. This constitutes more than a majority of our Board of Directors. Only independent directors serve on our Audit Committee, Nominating Committee, and Compensation Committee.

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Leadership Structure

        The Corporation chooses to separate the roles of Chairman and President & Chief Executive Officer. The President & Chief Executive Officer is responsible for implementing the strategic direction of the Corporation, as determined by the Board of Directors, and for the day-to-day leadership and performance of the Corporation. The Chairman oversees the agenda for and presides over Board of Director meetings, as well as provides leadership to the Board and facilitates communication between

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the Board of Directors and executive management. The Corporation's Chairman of the Board is considered independent under the SEC and Nasdaq standards for independence.

Risk Oversight

        The Board of Directors has a role in overseeing the Corporation's risks as a whole and at the committee level. The Audit Committee is primarily responsible for overseeing the risks the Corporation faces on behalf of the Board of Directors. The Audit Committee works closely with the Corporation's Chairman of the Board, President & Chief Executive Officer, and ACNB Bank's Chief Risk & Governance Officer, as well as with other members of management with respect to matters relating to risk management. The Audit Committee receives reports on risk management and the processes in place to monitor and control such exposures. The Audit Committee may also receive updates, from time to time, between meetings from management relating to risk oversight matters. The Audit Committee provides updates on its risk management activities to the full Board of Directors via the committee's meeting minutes. Further, members of management may make presentations on risk management to the full Board of Directors or another committee of the Board of Directors.

        In addition to the Audit Committee, other committees of the Board of Directors consider the risks within their areas of responsibility. For example, the Compensation Committee considers the risks that may be implicated by the Corporation's compensation practices. Also, the Strategic Planning Committee assesses the risks associated with the Corporation's executive management succession plans.

Director Independence

        In determining each director's and nominee's independence, the Board of Directors considered loan transactions between ACNB Bank and the individuals, their family members, and businesses with which they are associated. The table below includes a description of other categories or types of transactions, relationships or arrangements considered by the Board (in addition to those listed above and those transactions set forth under "Transactions with Directors and Executive Officers" below) in reaching its determination that the directors are independent.

        In each case, the Board of Directors determined that none of the transactions impaired the independence of the director.

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Directors of ACNB Corporation

        The following table sets forth, as of March 10, 201513, 2017 (in alphabetical order), selected information about the Corporation's directors and director nominees.

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Executive Officers of ACNB Corporation and/or Subsidiary

        The following table sets forth, as of March 10, 2015,13, 2017, selected information about the Corporation's Executive Officers, each of whom is appointed by the Board of Directors and each of whom holds office at the Board's discretion.

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Meetings and Committees of the Board of Directors

        The Board of Directors of ACNB Corporation met twelve (12)fifteen (15) times during 2014.2016. The Corporation maintains an Audit Committee (which is established in accordance with Section 3(a)(58)(A) of the Securities Exchange Act of 1934), Executive Committee, Compensation Committee, Nominating Committee, and Strategic Planning Committee. A total of thirty-one (31)thirty-seven (37) Board and committee meetings of the Corporation's Board of Directors were held in 2014.2016. During 2014,2016, each of the directors attended at least 75% of the combined total number of meetings of the Corporation's Board of Directors and the committees of which he or she was a member. The Board of Directors has a written attendance policy statement which encourages and expects each director to attend the Annual Meeting of Shareholders. All of theTwelve (12) directors attended the 20142016 Annual Meeting of Shareholders, and we expect that they will all attend the 20152017 Annual Meeting of Shareholders.

        Audit Committee.    Members of the Audit Committee during 20142016 were Daniel W. Potts, who served as Chair, Richard L. Alloway II, Frank Elsner, III, Robert W. Miller, Donna M. Newell, J. Emmett Patterson, Marian B. Schultz and David L. Sites and Harry L. Wheeler.Sites. Each of these directors is "independent" as defined in the SEC and Nasdaq standards for independence. In addition, Thomas A. Ritter, David W. Cathell, Lynda L. Glass and James P. Helt were invited to attend committee meetings. The principal duties of the Audit Committee, as set forth in its charter, include reviewing the Corporation's financial reporting process and systems of internal accounting and financial controls; reviewing significant audit

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and accounting principles, policies and practices; reviewing performance of internal auditing procedures; overseeing risk management; and, recommending annually to the Board of Directors the engagement of an independent auditor. The Audit Committee has a charter which is available under the Corporate Governance Documents section of the Investor Relations/ACNB Corporation page of ACNB Bank's website at www.acnb.com. The Audit Committee met five (5) times during 2014.2016.

        Executive Committee.    Members of the Executive Committee during 20142016 were Frank Elsner, III, who served as Chair, Daniel W. Potts, Marian B. Schultz, David L. Sites, Alan J. Stock and James E. Williams. Each of these directors is "independent" as defined in the SEC and Nasdaq standards for independence. In addition, Thomas A. Ritter and James P. Helt served as an ex-officio membermembers of this committee, and David W. Cathell and Lynda L. Glass and James P. Helt were invited to attend committee meetings. The principal duties of the Executive Committee are to act on behalf of the Board between meetings and to evaluate governance issues. The Executive Committee has a charter which is available under the Corporate Governance Documents section of the Investor Relations/ACNB Corporation page of ACNB Bank's website at www.acnb.com. The Executive Committee met one (1) time during 2014.2016.

        Compensation Committee.    Members of the Compensation Committee during 20142016 were James E. Williams, who served as Chair, Frank Elsner, III, Scott L. Kelley, James J. Lott, J. Emmett Patterson, Marian B. Schultz and Alan J. Stock. Each of these directors is "independent" as defined in the SEC and Nasdaq standards for independence. The principal duties of the Compensation Committee include evaluating and recommending to the Board of Directors the executive officer compensation plans, policies and programs of the Corporation. The Compensation Committee has a charter which is available under the Corporate Governance Documents section of the Investor Relations/ACNB Corporation page of ACNB Bank's website at www.acnb.com. The Compensation Committee met five (5)ten (10) times during 2014.2016.

        Nominating Committee.    Members of the Nominating Committee during 20142016 were Marian B. Schultz, who served as Chair, Richard L. Alloway II, Frank Elsner, III, Donna M. Newell, Alan J. Stock Harry L. Wheeler and James E. Williams. Each of these directors is "independent" as defined in the SEC and Nasdaq standards for independence. The principal duties of the Nominating Committee include identifying qualified individuals to serve on the Board and recommending nominees to the Board. The Nominating Committee has a charter which is available under the Corporate Governance Documents section of the Investor Relations/ACNB Corporation page of ACNB Bank's website at www.acnb.com. The Nominating Committee met two (2) timesone (1) time during 2014.

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        Strategic Planning Committee.    Members of the Strategic Planning Committee during 20142016 were Frank Elsner, III, who served as Chair, Daniel W. Potts, Thomas A. Ritter, Marian B. Schultz, David L. Sites, Alan J. Stock and James E. Williams. The principal duties of the Strategic Planning Committee include overseeing the development of and monitoring the progress of the Corporation's strategic plan; keeping the Board of Directors informed of developments, trends and opportunities in the industry that might help improve the Corporation's profitability, growth and/or customer service; and, establishing Board and senior management succession plans. The Strategic Planning Committee has a charter which is available under the Corporate Governance Documents section of the Investor Relations/ACNB Corporation page of ACNB Bank's website at www.acnb.com. The Strategic Planning Committee met six (6)five (5) times during 2014.2016.

Shareholder Communications

        The Board of Directors has formal shareholder communications processes for the submission of shareholder proposals and nomination of directors, as described below. In addition, shareholders may contact any member of the Board personally, by telephone or by written correspondence including email. Written communications received by the Corporation from shareholders are shared with the full Board as deemed appropriate.

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Submission of Shareholder Proposals

        In order for a shareholder proposal (other than director nominations) to be considered for inclusion in ACNB Corporation's proxy statement for next year's annual meeting, the written proposal must be received by the Corporation no later than November 25, 2015.28, 2017. Proposals may be sent to Lynda L. Glass, Executive Vice President, President/Secretary & Chief Governance Officer of ACNB Corporation, at 16 Lincoln Square, P.O. Box 3129, Gettysburg, Pennsylvania 17325.

        All proposals must comply with SEC regulations regarding the inclusion of shareholder proposals in company-sponsored proxy materials. If a shareholder proposal is submitted to the Corporation after November 25, 2015,28, 2017, it is considered untimely; and, although the proposal may be considered at the annual meeting, the Corporation is not obligated to include it in the 20162018 proxy statement.

Employee Code of Ethics

        Since May 1994, ACNB Bank, formerly Adams County National Bank, has had a Conflict of Interest/Code of Ethics. In 2003, as required by law and regulation, the Corporation's Board of Directors adopted a Code of Ethics which is applicable to our directors, officers and employees, and which has been amended as necessary from time to time.

        The Code of Ethics encourages individuals to report any conduct that they believe in good faith to be an actual or apparent violation of the Code of Ethics to ACNB Corporation's Chief Governance Officer. The Code of Ethics is available under the Corporate Governance Documents section of the Investor Relations/ACNB Corporation page of ACNB Bank's website at www.acnb.com.

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ELECTION OF DIRECTORS

Nomination of Directors

        The Corporation has a standing Nominating Committee with a charter. Recommendations to the Board of Directors as to the nominees for election as directors at the Annual Meeting of Shareholders are provided by the Nominating Committee. The Nominating Committee will consider shareholder-recommended nominees for director, and shareholders who desire to propose an individual for consideration by the Board of Directors as a nominee for director should submit a recommendation in writing to the Secretary of the Corporation in compliance with the requirements of Article II, Sections 202, 203 and 203,205(b), of the Corporation's Bylaws. Any shareholder who intends to nominate a candidate for election to the Board of Directors must notify the Secretary of the Corporation in writing not less than fourteen (14) days prior to the date of any shareholder meeting called for the election of directors.

Qualification and Nomination of Directors

        The Corporation's Articles of Incorporation authorize the number of directors to be not less than five (5) and not more than twenty-five (25). Further, the Corporation's Articles of Incorporation and Bylaws provide for three (3) classes of directors with staggered terms of office of three (3) years that expire at successive annual meetings. Pursuant to Article II, Section 205, of the Corporation's Bylaws, no director or nominee shall stand for election, if as of the date of election, he or she shall have attained the age of seventy-two (72) years old. Currently, the number of directors is set at thirteen (13): Class 1 consists of five (5) directors, Class 2 consists of four (4) directors, and Class 3 consists of four (4) directors. However, pursuant to Article 11 of the Corporation's Articles of Incorporation and Article I, Section 105, of the Corporation's Bylaws, at each shareholder meeting for the election of directors, the shareholders determine how many directors will be elected to serve in each class. The Board of Directors believes that it is in the Corporation's best interest to fix the number of directors at the 20152017 Annual Meeting at thirteen (13)sixteen (16).

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        The proposed thirteen (13)sixteen (16) member Board of Directors will consist of five (5)six (6) Class 1 Directors, four (4)six (6) Class 2 Directors, and four (4) Class 3 Directors. Two (2) Class 1 Director seats shall be vacant and one (1) Class 2 Director seat shall be vacant. Due to Mr. Miller's resignation from the board, the Board of Directors believes it is in the best interests of the Corporation to leave his Class 1 Director seat vacant should a suitable candidate be identified to fill the seat. Currently, the Board of Directors has not identified any such candidate. In addition, in connection with the proposed acquisition of New Windsor Bancorp, Inc., the Corporation has agreed to increase the total number of directors that constitute the whole board to sixteen (16) and two (2) seats shall be reserved for New Windsor Bancorp, Inc.'s director nominees who meet the Corporation's requirements for board service. Should the proposed transaction be consummated, the Board of Directors currently expects to appoint Todd L. Herring as a Class 1 Director and D. Arthur Seibel, Jr. as a Class 2 Director. Each are currently directors of New Windsor Bancorp, Inc.

Shareholders will elect four (4) Class 23 Directors to serve for terms of three (3) years until their successors are elected and qualified and one (1) Class 2 Director to serve for a term of one (1) year until his successor is elected and qualified.

        The Nominating Committee believes that a director nominee must have the following attributes/qualifications before being recommended as a nominee: stock ownership in the Corporation, the willingness to commit time, a commitment to independence, a commitment to the Corporation's community, financial competence, a good reputation, integrity, good communication skills, and the willingness and ability to speak up for the interests of the Corporation. A director nominee shall also have expertise that strengthens the Board of Directors. When evaluating potential director nominees, the Nominating Committee considers the skills and expertise of the current Board members and seeks director nominees with knowledge, skills and abilities that enhance and complement—rather than duplicate—the experiences and skills already represented on the Board of Directors. Further, the Nominating Committee ensures director nominees complement the Corporation's strategic vision and direction, a fundamental priority for the Board of Directors. The Nominating Committee follows the same process for evaluating shareholder-recommended nominees for director.

        The Nominating Committee does not have a formal policy with respect to diversity; however, the Board and the Nominating Committee believe that it is essential that members of the Board of Directors represent diverse viewpoints and experience. In considering candidates for the Board, the Nominating Committee considers the entirety of each candidate's credentials in the context of these standards.

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        The Board of Directors nominated incumbent directors Donna M. Newell, DavidFrank Elsner, III, Scott L. SitesKelley and Alan J. StockDaniel W. Potts to serve as Class 23 Directors until the expiration of the term of the class or until their earlier death, resignation or removal from office. Furthermore, after the Nominating Committee review ofconsidered various internal and external sourcesfactors, including the fact that he will become President & Chief Executive Officer of information related to potential director nominees,the Corporation and ACNB Bank on May 5, 2017, upon the recommendation and approval of the Nominating Committee, the Board of Directors nominated Richard L. Alloway IIJames P. Helt to serve as a Class 3 Director until the expiration of the term of the class or until his earlier death, resignation or removal from office. The Board of Directors nominated incumbent director, Thomas A. Ritter, to serve as a Class 2 Director until the expiration of the term of the class or until his earlier death, resignation or removal from office. Ms. NewellMessrs. Elsner, Kelley, Potts and Messrs. Sites and StockRitter are presently members of the Board of Directors and have consented to serve another term as a director if reelected. Mr. AllowayHelt is a new nominee to the Board of Directors and has consented to serve if elected. If any of the nominees should be unavailable to serve for any reason, a majority of the Board of Directors then in office may fill the vacancy until the expiration of the term of the class of directors to which he or she was appointed.

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        The proxyholders intend to vote all proxies for the election of each of the nominees named below, unless you indicate that your vote should be withheld from any or all of them.

        The Board of Directors proposes the following nominees for election as Class 23 Directors at the annual meeting:

Class 23 Director Nominees

        The Board of Directors proposes the following nominee for election as a Class 2 Director at the annual meeting:

Class 2 Director Nominee

Thomas A. Ritter

        The Board of Directors recommends that shareholders voteFOR the proposalproposals to elect the nominees listed above.

Information as to Nominees and Directors

        Set forth below, as of March 10, 2015,13, 2017, are the principal occupations and certain other information regarding nominees for director and continuing directors including the experience, qualifications, attributes or skills that contribute to the nominee's or director's ability to oversee the management of the Corporation. Unless otherwise specified, all business experience is for the past five (5) years in the same or similar position. You will find information about their share ownership on pages 1214 through 14.16.

Class 1 Directors (to serve until 2016)2019)

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SHARE OWNERSHIP

Principal Shareholders

        As of December 31, 2014,2016, the Board of Directors knows of no person who owns of record or who is known to be the beneficial owner of more than 5% of the Corporation's outstanding common stock.

Beneficial Ownership of Executive Officers, Directors and Nominees

        The following table sets forth, as of December 31, 2014,2016, and from information received from the respective individuals, the amount and percentage of the common stock beneficially owned by each director, each nominee for director, each Named Executive Officer, and all Named Executive Officers, directors and nominees of the Corporation as a group. Unless otherwise noted, shares are held individually and the percentage of class is less than 1% of the outstanding common stock.

        Beneficial ownership of shares of ACNB Corporation common stock is determined in accordance with SEC Rule 13d-3, which provides that a person should be credited with the ownership of any stock held, directly or indirectly, through any contract, arrangement, understanding, relationship, or otherwise has or shares:

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Voting power, which includes the power to vote or to direct the voting of the stock; or,



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Investment power, which includes the power to dispose or direct the disposition of the stock; or,



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The right to acquire beneficial ownership within sixty (60) days after December 31, 2014.2016.

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        Unless otherwise indicated in a footnote appearing below the table, all shares reported in the table below are owned directly and individually by the reporting person. The number of shares owned by the directors, nominees and executive officersNamed Executive Officers is rounded to the whole share.

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COMPENSATION AND PLAN INFORMATION

Compensation of the Board of Directors of ACNB Corporation and ACNB BankSubsidiaries

        Directors of the Corporation are not compensated for their services. Further, ACNB Bank does not compensate employee directors for attendance at Board of Directors meetings or committee meetings. However, beginningBeginning April 1, 2014,2016, ACNB Bank's non-employee directors werehave been compensated for their services rendered to the Corporation and to ACNB Bank as follows:

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$11,00017,000 annual retainer;



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$550650 per Board meeting;



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$225 per hour for committee meetings with a minimum payment of $225;



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$200 for committee chair per meeting, unless otherwise specified;



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$400 for Audit Committee chair per meeting;



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$400 for Compensation Committee chair per meeting;



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$2,250 per month for Chairman of the Board;



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$600 allowance for a half-day seminar plus expenses, if applicable, and $1,000 allowance for a full-day seminar plus expenses, if applicable; and,



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$125 per hour for continuing education by external, online web-based training, given preapproval.

        Fifty percent (50%) of each director's annual retainer, as paid on a quarterly basis, is submitted as a voluntary cash purchase of ACNB Corporation common stock through the Corporation's Dividend Reinvestment and Stock Purchase Plan.

The following table summarizes the compensation of directors during 2014:2016:

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Director Deferred Fee Plan

        In January 2001, ACNB Bank established a director deferred fee plan. Directors Alloway, Elsner, Kelley, Lott, Miller, Newell, Patterson, Schultz, Sites, Stock Wheeler and Williams participated in 2014.2016. Directors may defer up to 100% of the director's income. Benefits are payable upon termination of service, change of control, and by specific participant election in accordance with IRS Code Section 409A. The deferred fees earn interest, and the interest and plan expenses are funded by bank-owned life insurance (BOLI).

Director Supplemental Life Insurance Plan

        ACNB Bank has a director supplemental life insurance plan. All non-employee directors are eligible for the life insurance benefit. The plan currently insures twelve (12) directors. The director life insurance benefit of $250,000 per participating director shall be provided unless the director separates from service prior to reaching the retirement age, in which case the benefit is $100,000. This life insurance benefit will beis funded through a single premium BOLI program because BOLI is a more cost-efficient way of providing the benefits. The amounts of death benefits is the amount set forth in the individual's policy endorsement. The eligible participating directors are not required to pay any premiums on the life insurance policy, but have the imputed value of the insurance coverage included in their taxable incomes.

Long-Term Care Insurance

        ACNB Bank provides long-term care insurance to directors, and eligibility is subject to medical underwriting acceptance. The plan currently insures ten (10)nine (9) directors. The eligible participating directors are not required to pay any premiums. The long-term care insurance provides a monthly maximum base benefit of $4,000 for long-term care needs.

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Executive Compensation

Compensation Discussion and Analysis

Named Executive Officers

        The Compensation Committee is charged with recommending to the Board of Directors of ACNB Corporation the compensation for all of the Named Executive Officers. For the year 2014,2016, our Named Executive Officers include those individuals in the following table:

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Corporation Performance vs. Named Executive Officer Base Salary Increase

        The Corporation is committed to maintaining a strong, healthy financial institution and is committed to our shareholders. We highlight below our corporate performance and the Named Executive Officers' (except the President & Chief Executive Officer of Russell Insurance Group, Inc.) base salary which is the main component of our Named Executive Officers' compensation.

Compensation Objectives and Policies

        The primary objectivesobjective of the Corporation's compensation philosophy remainremains to attract, motivate, reward and retain executives who

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will maintain the safety and soundness of the Corporation



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and its subsidiaries. In addition, the Corporation's compensation philosophy aims to sustain and enhance long-term investor value,



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enforce internal controls deemed appropriate by our auditors and regulators, and



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execute the strategic plans as prioritized by the Board of Directors.

        The Compensation Committee and the Board of Directors of the Corporation seek to establish fair compensation policies in order to attract, motivate, reward and retain competent managers whose efforts will enhance the Corporation's profitability and growth without exposing the Corporation to undue risk. The Compensation Committee treats compensation as an evolving process depending on the strategic objectives of the Corporation, as determined by the Board of Directors at that time.

The Role of the Executive Officers in Setting Compensation

        The Named Executive Officers do not participate in the determination process of their respective annual base salaries and are not present when their respective compensation is discussed by the Compensation Committee or discussed and approved by the Board of Directors. Only

        In 2016, the President & Chief Executive Officer of the Corporation providesprovided insight to the Compensation Committee on the performance and compensation of the other Named Executive Officers as illustrated below. The President & Chief Executive Officer of the Corporation also assisted in establishing performance goals and objectives for the other Named Executive Officers, with the exception of Mr. Russell.

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The Compensation Process for the Named Executive Officers,
except the President & Chief Executive Officer of Russell Insurance Group, Inc.

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The Compensation Process for the President & Chief Executive Officer
of Russell Insurance Group, Inc.

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The Role of a Consultant in Setting Compensation

        The Compensation Committee may in its sole discretion retain or seek the advice of a compensation consultant or other adviser. The Compensation Committee is directly responsible for retaining, determining the independence, determining if a conflict of interest exists, compensating, and overseeing the work of its advisers.

        The Compensation Committee chose not to engageengaged Mosteller & Associates ("Mosteller"), a compensation consultant forconsulting firm in 2016. The Compensation Committee determined that Mosteller was independent and that no conflict of interest existed. Mosteller was charged with updating the year 2014 aspeer group to be used by the Compensation Committee and providing peer executive compensation information which the Compensation Committee considered when making recommendations related to executive compensation and bonus awards. The Compensation Committee also reviewed and considered educational materials from various seminars and conferences, as well as other resources, as further explained inBenchmarking below.

Benchmarking

        In 2016, the shareholders' responseCompensation Committee engaged Mosteller to present compensation comparisons for peer institutions. Mosteller provided a two-part executive compensation study report. In creating the first comparison, Mosteller used compensation data from five surveys: (1) ERI which included commercial banks with approximately $1.2 billion in assets in the mid-Atlantic region focusing on the Gettysburg/York PA metropolitan area; (2) CompAnalyst which included the financial services industry with approximately $1 to $2 billion in assets focusing on the Gettysburg/York PA metropolitan area; (3) Towers Watson which focused on the financial services industry with less than $5 billion in assets nationwide; (4) L.R. Webber Associates, Inc.'s 2015 Salary & Benefits Survey which focused on financial institutions with greater than $1 billion in assets; and, (5) Mosteller & Associates' proprietary database of regional banks with assets from $1 to $2 billion primarily in the mid-Atlantic region. The compensation data below compares the salary and bonus compensation level by position to the Say on Pay vote and choseaverage compensation levels reflected in the market surveys. Mr. Russell's compensation was not to materially changeanalyzed in this comparison based upon the contractual nature of his compensation.

        As illustrated below, the base compensation for the Named Executive Officers in 2014.fell between the 50^th and 75^th percentiles, except for the compensation of Mr. Ritter which fell between the 25^th and 50^th percentiles. The total cash component of the Named Executive Officers fell between the 25^th and 50^th percentiles, except for the total cash paid to Mr. Ritter which fell below the 25^th percentile.

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        In 2014,creating the second comparison, Mosteller, with input from the Compensation Committee and the President & Chief Executive Officer of ACNB Corporation, did not benchmark itschose the following institutions as the Corporation's peers for 2016 for which the Compensation Committee reviewed the compensation policies against a peer group.for the relevant institution's Named Executive Officers garnered from that institution's proxy.

        The Compensation Committee considered the following information regarding the performance of the peer institutions versus the Corporation's performance:

        Information gathered from the peers was then used to compare the top paid Named Executive Officers of ACNB Corporation to the top paid Named Executive Officers in the above peers, based solely on ranking of total compensation and not a position-by-position comparison or a merit comparison. The table below illustrates the Named Executive Officer's 2015 pay as a percentage to the

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peer average of the individual who holds the same compensation ranking as the ACNB Named Executive Officer.

        The Compensation Committee reviewed the information gathered from the proxies of the peer group, including the compensation of the Named Executive Officers from the peer institutions. It also used the information in the table above to educate itself ondetermine the depth of compensation arrangements used at peer institutions. It did not make any specific adjustment in any element of compensation based upon any specific information provided in the Mosteller report, except increasing the base compensation of the President & Chief Executive Officer to be more competitive with the compensation provided to his peers as outlined in the peers' respective proxies and in the Mosteller report.

        The Compensation Committee also reviewed information it received from various seminars, conferences and publications. This information provides general compensation trends and is not used to specifically benchmark any specific element of executive compensation to any specific financial institution or group of financial institutions, but is only used as an educational source as to the current trends in compensation as outlined below.compensation.

The Role of the Shareholders' Say on Pay Vote

        At the 20142016 Annual Meeting of Shareholders, the shareholders overwhelmingly voted in favor of approving the compensation of the Corporation's Named Executive Officers as presented in the

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Compensation Discussion and Analysis presented in the Corporation's proxy statement dated March 25, 2014.29, 2016. The Compensation Committee will take the results of the vote, which has been consistently in favor of approving the compensation of the Corporation's Named Executive Officers, as well as the shareholders' vote on the frequency of the Say on Pay vote, into consideration in awarding compensation in the future consistent with the policies and practices outlined in the Compensation Discussion and Analysis and in providing for an annual Say on Pay vote.

Components of Compensation

        While the specific amount of compensation provided to the Corporation's executives may slightly differ, the components of compensation are generally the same for our Named Executive Officers. For 2014, 2016,

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the Corporation's executive compensation and benefits package consisted primarily of base salary, bonus, retirement plans, and employee health and welfare benefit plans.

Summary of Components of Compensation

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Base Salary

Named Executive Officers Employed by ACNB Bank

        The Compensation Committee believes that base salary should be the primary component of compensation. By setting base salary as the primary component of compensation, we discourage excessive risk-taking by our Named Executive Officers. Fixed compensation provides the executive with the security of knowing that the majority of his or her compensation is not tied to market fluctuations. The amount of base salary is designed to retain Named Executive Officers who can maintain the safety and soundness of ACNB Corporation and who can further the strategic objectives of the Corporation and/or a subsidiary of the Corporation and provide leadership where needed. In recommending base salary, the Compensation Committee does not take into consideration any other forms of compensation which are and which may not be offered to the Named Executive Officers. The Compensation Committee believes that, by providing compensation without delay in the form of base salaries, it will successfully further the Corporation's goals of providing a stable environment for its Named Executive Officers which, in turn, encourages them to maintain the safety and soundness of the Corporation.

        Base salaries for our Named Executive Officers are established based upon their respective responsibilities, individual performance, longevity with the Corporation and/or a subsidiary of the Corporation, and key Corporation performance measures including profitability and growth. The Compensation Committee also considered five-year historical data of the Named Executive Officers' compensation; peer comparisons; updates on Russell Insurance Group, Inc., Trust & Investment Services, Risk Management, Board Reporting and Communications, Investor/Public Relations, Strategic Leadership, and Management and Organizational Development; and, other general information. The Compensation Committee and the Board of Directors of the Corporation do not assign specific quantitative measures to subjective factors, profitability and growth, or performance targets for purposes of base salary increases, but uses its business judgment to determine if the Corporation's profitability and growth are sufficient enough to allow the Corporation the flexibility to award merit increases such that the increase would be a safe and sound practice. For the year ended December 31, 2013,2015, the Corporation reported an increase of fiveseven and one-tenth percent (5%(7.1%) in net income, net income on aan increase in assets of five and three-tenths percent (5.3%), and an increase in earnings per share basis increasedof seven cents ($0.07), and shareholders' equity increased by five and one-half percent (5.5%(7.0%).

        The Named Executive Officers are expected to assist the Corporation in sustaining and enhancing long-term investor value by maintaining the safety and soundness of the Corporation and its subsidiaries, enforcing internal controls deemed appropriate by our auditors and regulators, executing the strategic plans as prioritized by the Board of Directors, providing leadership and organizational development, and assisting in public relations. A Named Executive Officer's capacity to perform these tasks and achievement of these tasks are taken into consideration in determining whether the Named Executive Officer has performed as expected or has had outstanding performance.

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        The base salary increases are illustrated in the table below:

        Although the individual performance reviews for the Named Executive Officers of the Corporation and/or ACNB Bank were very favorable, these Named Executive Officers' respective salaries, except for Mr. Ritter's, were not substantially increased in an effort to preserve the assets of the Corporation and its banking subsidiary and the increases were not a true reflection of the respective Named Executive Officer's performance or the performance of the Corporation or ACNB Bank. Mr. Ritter's base salary was increased greater than the other Named Executive Officers' salaries as a result of a review of the salaries of his peers as discussed above inBenchmarking.

Named Executive Officer Employed by Russell Insurance Group, Inc.

        The Board of Directors of Russell Insurance Group, Inc. recommends the amount of cash compensation for the President & Chief Executive Officer of Russell Insurance Group, Inc. at the time of employment agreement discussions to the Compensation Committee which reviews the recommendation. The Compensation Committee then makes an independent recommendation to the Board of Directors of ACNB Corporation, which sets the amount of cash compensation for all Named Executive Officers. The base amount and forms of compensation awarded the President & Chief Executive Officer of Russell Insurance Group, Inc. are based upon previous contract negotiations, the performance of Russell Insurance Group, Inc., and the role that the President & Chief Executive Officer of Russell Insurance Group, Inc. performs in the highly relationship-oriented industry of insurance sales.

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Bonus Awards

President & Chief Executive Officer of Russell Insurance Group, Inc. Bonus

        The President & Chief Executive Officer of Russell Insurance Group, Inc. is the only Named Executive Officer who has a non-discretionarynondiscretionary formulized bonus structure which is addressed in his employment agreement. Given that his duties include marketing and sales, the Board of Directors of Russell Insurance Group, Inc. believes that offering him a formulized bonus will increase the profitability of the insurance subsidiary, and therefore the Corporation, because it incents him to exceed $1 million in pre-tax profits in a calendar year. The bonus structure is equal to five percent (5%) of the pre-tax income (based on historical agency accounting system) earned by Russell Insurance Group, Inc. during the preceding calendar year, provided that the actual pre-tax profits for that year exceeds $1 million; further provided, however, if Russell Insurance Group, Inc. is assessed with impairment charges, then the Board of Directors of Russell Insurance Group, Inc. may, at its sole discretion, award, adjust, or not award the bonus for any year in which impairment charges are applied to the Russell Insurance Group, Inc. income statement. This bonus structure also contains a clawback provision allowing the Corporation to recoup the appropriate funds if the Corporation is required to restate all or a portion of its financial statements as a result of or related to a restatement of Russell Insurance Group, Inc.'s financial statements or if the Corporation determines in its sole discretion that it is required by state or federal laws or regulations to implement the clawback provision.

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Discretionary Bonuses to ACNB Bank Employees

        The Compensation Committee may recommend to the Board of Directors discretionary bonus awards for the Named Executive Officers, or any other employee or group of employees, for the purpose of rewarding exceptional effort and performance. ForIn the year 2014,2016, after reviewing the audited financial statements of the Corporation, had not set forth specific criteria for bonuses, but awarded bonuses on a case-by-case basis and used the Compensation Committee members' experience and individual business judgment whenused the ACNB Bank Variable Compensation Plan, as discussed in more detail below, in determining whether a bonus was appropriate. In the second quarter of 2014, after receiving and reviewing the Corporation's audited financial statements for the year ended December 31, 2013, the Compensation Committee recommended and the Board approved bonuses forkind of bonus to award the Named Executive Officers, (excludingexcept the President & Chief Executive Officer of Russell Insurance Group, Inc. as hiswhose bonus structure is provided in his employment agreement as described in the paragraph above), based upon the general financial performancedetermined by contract. The amount of the Corporation forbonus was determined at the year 2013discretion of the Compensation Committee after review of all available resources, as discussed above, and based upon their business judgment. Upon approval by the Named Executive Officer's performance. FiftyBoard of Directors, a maximum of fifty-five percent (50%(55%) of the bonus awarded to the respective Named Executive Officer was deposited for a cash purchaseaward. The remaining portion was in the form of an equity award under the ACNB Corporation stock2009 Restricted Stock Plan, which was purchased through the Corporation's Dividend Reinvestment and Stock Purchase Plan and intended to further align the interests of the Named Executive Officer with those of the shareholders.

ACNB Bank Variable Compensation Plan

        Effective January 1, 2014, the Compensation Committee established the ACNB Bank Variable Compensation Plan (Plan), which provides guidelines for awarding cash and/or equity incentive bonuses in the future and which guidelines cover employees of the banking subsidiary, ACNB Bank. Under the Plan, the Compensation Committee may make a recommendation to the Board of Directors to award stock under the ACNB Corporation 2009 Restricted Stock Plan if it chooses to make equity awards. The Board of Directors also reserves the right to amend, suspend or terminate the Plan at any time. The guidelines contained in the Plan include general restrictions such asas:

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the award formulas are to be constructed to align the interests of the employee with those of the shareholders;



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the employee must have an overall rating of "Good" on the employee's most recent individual performance appraisal;

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no incentive bonuses may be awarded if the Bank's CAMELS rating assigned by its regulators falls below a certain rating;



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no incentive bonuses will be awarded if the Board of Directors determines that the dividend payable to the shareholders is not reasonable; and,



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all bonuses will beare subject to a clawback provision.

        For the 2014 year, the Compensation Committee determined that it would maintain its ability to recommend discretionary bonuses in 2015 for 2014 performance. In moving toward a non-discretionary bonus structure, the Compensation Committee set forth certain criteria that it would review, although the criteria are not binding, in determining whether to consider granting bonuses in 2015 for the 2014 year.Table of Contents

2014 Criteria for Review In Considering WhetherConsidered in Deciding to Grant a Discretionary Bonus Under the
ACNB Bank Variable Compensation Plan

        As discussed above, a maximum of fifty-five percent (55%) of the bonus awarded to the respective Named Executive Officer was a cash award paid in 2016 for 2015 performance. The remaining portion of the bonus was in the form of an equity award under the ACNB Corporation 2009 Restricted Stock Plan, as purchased through the Corporation's Dividend Reinvestment and Stock Purchase Plan. The President & Chief Executive Officer of the Corporation and the President of the Bank were awarded more shares, given their positions, than the other Named Executive Officers employed by ACNB Bank. The other Named Executive Officers were awarded an equal number of shares as all participated in the financial success of the Corporation for the year of 2015. The shares awarded to the Named Executive Officers were to vest in one-third (¹/3) tranches, with the first third vesting in 2016. The Compensation Committee intends to continue to use restricted stock through the ACNB Corporation 2009 Restricted Stock Plan in the future in conjunction with the ACNB Bank Variable Compensation Plan with the intended purpose to encourage stability and longevity in executive management.

ACNB Corporation 2009 Restricted Stock Plan

        In 2009, the shareholders approved a restricted stock plan for the benefit of employees and directors of ACNB Corporation and ACNB Bank, as determined by the Compensation Committee. The plan is intended to advance the best interests of the Corporation and its shareholders by providing those persons who have responsibility for the Corporation's growth with additional incentives by encouraging them to acquire an ownership interest in the Corporation and, thereby, further encouraging them to contribute to the success of the Corporation and ACNB Bank. The price volatility inherent in any form of performance-based equity compensation remains the main reason why other forms of compensation will be relied upon more heavily than equity compensation. The Compensation Committee granted shares of restricted stock in 2016 in conjunction with the ACNB Bank Variable Compensation Plan, as discussed in detail above.

Retirement Plans

        The Compensation Committee believes that retirement benefits are another important way to provide long-term financial security to employees, thus encouraging longevity and a low employee turnover rate. As the defined benefit plan and 401(k) plan are tax qualified retirement plans, the Corporation's retirement plans are not tied to Corporation or individual performance.

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Defined Benefit Plan

        The Corporation's banking subsidiary, ACNB Bank, maintains a defined benefit plan which is available to all eligible employees hired on or before March 31, 2012. The plan provides a prospective benefit commencing at age sixty-five (65) for the employee's lifetime. If an employee has completed thirty (30) or more years of service, the employee is eligible to retire at age sixty-two (62) and receive full benefits. The plan contains a five (5) year vesting provision to ensure that the plan rewards employees for longevity. The amount paid under the plan is based upon a formula outlined in the plan and which is applicable to all eligible ACNB Bank employees. The defined benefit plan is a very effective tool for employee retention and for providing long-term incentive compensation. All Named Executive Officers, with the exception of the President & Chief Executive Officer of Russell Insurance Group, Inc., are employees of ACNB Bank and are eligible to participate in the plan.

401(k) Plan

        Both ACNB Bank and Russell Insurance Group, Inc. maintain a 401(k) plan which allows employees to save their own money for retirement, to earn a matching contribution from the subsidiary, and to direct the investment of all funds in the 401(k) plan. The percentage of match contributed to

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the Named Executive Officer's account is the same as contributed to all other eligible employees in each plan and is prescribed by the Internal Revenue Code. These plans are viewed as a necessity to successfully hire and retain employees in a competitive marketplace. All Named Executive Officers participate in ACNB Bank's 401(k) plan, except the President & Chief Executive Officer of Russell Insurance Group, Inc. who participates in Russell Insurance Group, Inc.'s 401(k) plan.

Supplemental Executive Retirement Plan

        In 2014,2016, all Named Executive Officers, with the exception of the President & Chief Executive Officer of Russell Insurance Group, Inc., were parties to supplemental executive retirement plan (SERP) agreements. The SERP agreements were designed to account for some of the limitations with traditional pension plans and the reduction in benefits under ACNB Bank's defined benefit plan, and are intended to provide essential executive officers with an incentive to remain with the Corporation until retirement as opposed to terminating employment before retirement to work for a competitor. The triggering events for payment under the SERP agreements are reaching retirement age as delineated in the SERP agreement, change ofin control followed by termination of employment, or death. Benefit amounts for a termination prior to retirement age will be determined by the individual's number of years of service encouraging longevity with the Corporation and/or ACNB Bank, unless the termination follows a change in control, at which time, the Named Executive Officer will be fully vested in the SERP benefit. Payments under the SERP agreements are made after the Named Executive Officer reaches normal retirement age as defined in the respective agreement. The SERP provides no current remuneration to the applicable Named Executive Officers and, therefore, is not taken into consideration when determining base salary.

Health and Welfare Plans

        Health and welfare plans are not tied to the Corporation or individual performance. The cost of providing such benefits to all eligible employees is not taken into account when determining specific salaries of the Named Executive Officers and is a cost of doing business.

Insurance Plans

        Group life, group disability, vision, and health insurance are available to all eligible employees. Such plans are standard in the industry and in the geographic area for all industries, as well as necessary to compete for talented and committed employees at all levels of the Corporation.

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Supplemental Life Insurance Plan

        The Corporation's supplemental life insurance plan provides a split-dollar share of death benefits to the Named Executive Officer's beneficiary, depending upon the Named Executive Officer's eligibility to receive payments. The plan is funded with bank-owned life insurance and is used to provide an additional benefit to certain officers, including the Named Executive Officers, with a minimal cost to the Corporation. Split-dollar life insurance plans are widely available in the banking industry because the Corporation will recover its plan costs upon the death of the Named Executive Officer and the Named Executive Officer's beneficiary will receive a split of the insurance proceeds. Although this benefit does not provide any current remuneration to the Named Executive Officer, it provides further incentive for longevity with the Corporation and/or a subsidiary of the Corporation as it provides the executive the ability to provide some benefit to his or her family after his or her death. As the Corporation will recover its plan costs, the cost of the plan is not taken into consideration when determining base salary.

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Long-Term Care Insurance

        The Corporation provides long-term care insurance to certain officers, including the Named Executive Officers employed by the Corporation's banking subsidiary, ACNB Bank. The cost of providing this benefit is offset by interest earned on bank-owned life insurance on the life of the Named Executive Officer. Long-term care insurance is seen as an additional benefit used to attract and retain competent executives at minimal cost; therefore, the cost of the plan is not taken into consideration when determining base salary or other benefits.

Perquisites

        The Corporation provides either a Corporation-owned or Corporation-leased vehicle to the President & Chief Executive Officer of ACNB BankCorporation and to the President & Chief Executive Officer of Russell Insurance Group, Inc. The provision of a Corporation vehicle to these individuals is a customary benefit in the financial services industry as individuals in these positions frequently engage in public relations on behalf of the Corporation, ACNB Bank and/or Russell Insurance Group, Inc.

Equity Compensation

        In 2009, The Bank also provides a country club membership to the shareholders approved a restricted stock plan for the benefit of employees and directorsPresident of ACNB CorporationBank for his use in entertaining clients and ACNB Bank, as determined by the Compensation Committee. The plan is intended to advance the best interestspotential clients of the Corporation and its shareholders by providing those persons who have responsibility for the Corporation's growth with additional incentives by encouraging them to acquire an ownership interest in the Corporation and, thereby, further encouraging them to contribute to the success of the Corporation and ACNB Bank. The price volatility inherent in any form of performance-based equity compensation remains the main reason why other forms of compensation will be relied upon more heavily than equity compensation. The Compensation Committee has not yet granted any shares of restricted stock and is also still engaging in a thorough analysis of the industry and review of criteria to determine the best method to enhance shareholder value by providing an incentive to its executives under the plan.

        Although the Corporation did not specifically grant equity awards in 2014, in the second quarter of 2014, the Compensation Committee recommended and the Board approved cash bonuses for the Named Executive Officers (excluding the President & Chief Executive Officer of Russell Insurance Group, Inc.) as more fully described underDiscretionary Bonuses to ACNB Bank Employees above. Fifty percent (50%) of the bonus awarded to the respective Named Executive Officer was deposited for a cash purchase of Corporation stock through the Corporation's Dividend Reinvestment and Stock Purchase Plan to further align the interests of the Named Executive Officer with those of the shareholders.

Agreements

        The Corporation and ACNB Bank have entered into employment agreements with the President & Chief Executive Officer;Officer, the Executive Vice President, President/Secretary & Chief Governance Officer; and,Officer, the Executive Vice President, President/Treasurer & Chief Financial Officer.Officer, and the President of ACNB Bank. The Corporation and Russell Insurance Group, Inc. have entered into an employment agreement with the President & Chief Executive Officer of Russell Insurance Group, Inc. And, ACNB Bank has entered into an employment agreement with the Executive Vice President of Banking Services.

Triggering Events

        The employment agreements with the President & Chief Executive Officer;Officer, the Executive Vice President, President/Secretary & Chief Governance Officer;Officer, the Executive Vice President,President/ Treasurer & Chief Financial Officer;Officer, and the Executive Vice President of Banking Services of ACNB Bank are similar

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and any difference is found in payment amounts which are adjusted given the respective role in the Corporation and/or ACNB Bank and the current trends in the financial services industry. In determining the triggering events in these agreements, the Corporation used triggering events which are standard and prevalent in the industry. The contracts are designed to compensate the Named Executive Officer if the Named Executive Officer is terminated without cause, is terminated after a change in control, or terminates employment for good reason. As the agreements are three (3) years in duration and as the Named Executive

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Officer has agreed to noncompetition provisions in the agreement, the Corporation believes that it is only appropriate that if the Named Executive Officer is terminated without cause or if the Corporation imposes a condition of employment upon the Named Executive Officer which would be considered a good reason for the Named Executive Officer to terminate employment under the agreement (in effect, if the Corporation or ACNB Bank breaches the agreement), then the Named Executive Officer should be paid the predetermined amount as damages as a result of the Corporation or ACNB Bank violating the employment agreement. Alternatively, if the Corporation or ACNB Bank undergoes a change in control and as a result the Named Executive Officer's employment is terminated by either the Named Executive Officer or the successor corporation, the Corporation believes that it is in the best interests of the shareholders to provide the Named Executive Officer with security in order to ensure that decisions regarding potential changes in control are made in the best interests of the shareholders and that personal concerns regarding subsequent employment are minimized. The contracts give the Named Executive Officer the security of knowing that if he or she is terminated in one of those scenarios that he or she will receive some form of compensation during the transition phase from working for the Corporation to finding another position. In addition, the contracts contain a noncompetition provision, whereby the Named Executive Officer is not allowed to compete with the Corporation or ACNB Bank or solicit customers or employees of the Corporation or ACNB Bank for a specific period of time. The time period in which the Named Executive Officer receives compensation is related to the time period that the noncompetition provision is in effect.

        The three (3) year contract for the President & Chief Executive Officer of Russell Insurance Group, Inc. contains a payment trigger if his employment agreement is terminated without cause or he terminates employment for good reason. Therefore, if he terminates employment without good reason, he will not receive any payment. If there is a change in control, he will only receive a payment if a subsequent termination of employment meets the definition of a termination without cause or a voluntary termination for good reason. Given his role at Russell Insurance Group, Inc., and not at the Corporation, the Compensation Committee believes the triggering events are appropriate.

        The triggering events for payment under the SERP agreements for the applicable Named Executive Officers are reaching retirement age as delineated in the SERP agreement, change ofin control followed by termination of employment, or death. Benefit amounts for a termination prior to retirement age will be determined by the individual's number of years of service encouraging longevity with the Corporation and/or ACNB Bank, unless the termination follows a change in control, at which time, the Named Executive Officer will be fully vested in the SERP benefit. Payments under the SERP agreements are made after the Named Executive Officer reaches normal retirement age as defined in the respective agreement.

Vesting

        The SERPs are subject to a vesting mechanism such that if the Named Executive Officer terminates employment prior to normal retirement age, the Named Executive Officer will receive a reduced benefit. Given the positions held by the applicable Named Executive Officers and the likelihood that their service with the Corporation and/or ACNB Bank would be terminated in the event of a change in control of the Corporation, the Named Executive Officers will become fully vested in the SERPs upon such termination. The employment agreements are not subject to vesting requirements as vesting of employment agreements is not industry standard, it would not further the Corporation's

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compensation philosophy, and the Named Executive Officers have longevity with the Corporation and/or a subsidiary of the Corporation.

Accounting and Tax Treatments

        In the case that one of the events which trigger a payment under the ACNB Corporation and/orand ACNB Bank employment agreements occurs and a payment is made, if the payment is subject to the

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Internal Revenue Code Section 4999 (also referred to as 280G) penalty, then the Named Executive Officer will receive additional compensation such that, after taxes, the Named Executive Officer will receive what he or she is entitled to under the agreement. The gross-up provision is standard in employment agreements given to Named Executive Officers at Pennsylvania community banks and is intended to place the Named Executive Officer in the same financial position that the parties intended. The gross-up amount is not taken into consideration when determining annual base salary or other annual compensation awards, but was taken into account when determining the amount of each triggering event in the respective contract.

        All of the Named Executive Officers' agreements are designed to comply with or be exempt from the application of Internal Revenue Code Section 409A.

Hedging/Pledging

        Employees who own shares outright are permitted to hedge or pledge shares, subject to the Corporation's Insider Trading Policy Statement that restricts certain transactions prior to the release of certain nonpublic information.

Ownership Guidelines

        At this time, the Corporation does not require its Named Executive Officers to own a certain number of shares of Corporation stock. However, with the exception of the President & Chief Executive Officer of Russell Insurance Group, Inc., as noted above, a portion of the respective Named Executive Officer's (except the President & Chief Executive Officer of Russell Insurance Group, Inc.) bonusbonuses awarded in 2014 was deposited for a cash purchase of2015 and 2016 were equity awards under the ACNB Corporation stock through the Corporation's Dividend Reinvestment and2009 Restricted Stock Purchase Plan to further align the interests of the Named Executive Officer with those of the shareholders.

Clawbacks

        Both the ACNB Bank Variable Compensation Plan and the President & Chief Executive Officer of Russell Insurance Group, Inc.'s bonus structure contain clawback provisions. Under the ACNB Bank Variable Compensation Plan, in the event that the Corporation or ACNB Bank is required to prepare an accounting restatement because of the material noncompliance of the Corporation or ACNB Bank with any financial reporting requirementsrequirement and, if within the previous three (3) years from the date of the restatement, an employee received an award under the plan, the employee shall return and refund to the Bank the excess of what would have been paid under the accounting restatement. In the event that the Corporation or the Bank is required to prepare an accounting restatement because of the employee's misconduct or fraudulent activity, then the employee shall return and refund to the Bank the entire award received based upon the erroneous data.

        Under the President & Chief Executive Officer of Russell Insurance Group, Inc.'s employment agreement, which contains his bonus structure, the Corporation is allowed to recoup the appropriate funds if the Corporation is required to restate all or a portion of its financial statements as a result of or related to a restatement of Russell Insurance Group, Inc.'s financial statements or if the Corporation determines in its sole discretion that it is required by state or federal laws or regulations to implement the clawback provision.

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Material Differences in Compensation Awarded to Each Named Executive Officer

        The Named Executive Officers receive base salaries commensurate with their positions, responsibilities, and past performance as recommended by the Compensation Committee and approved by the Board of Directors of ACNB Corporation using their respective business judgment. The amount of net income generated by Russell Insurance Group, Inc. is also taken into consideration when determining the President & Chief Executive Officer of Russell Insurance Group, Inc.'s base salary and bonus, which is based upon a formula provided in his employment agreement and discussed in more detail underBonus Awards above.

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        As illustrated below, the Named Executive Officers are provided similar benefits, except the President & Chief Executive Officer of Russell Insurance Group, Inc. does not participate in those benefits that are only offered to Named Executive Officers employed by ACNB Bank by virtue of the terms of the respective plan. Any differences in the amount provided under the respective benefit is determined based upon each Named Executive Officer's position and years of service.

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COMPENSATION COMMITTEE REPORT

        The Compensation Committee has reviewed and discussed the Compensation Discussion and Analysis with management and, based on the review and discussions, the Compensation Committee recommended to the Board of Directors that the Compensation Discussion and Analysis be included in ACNB Corporation's proxy statement.

        This report is furnished by the Compensation Committee.

James E. Williams, Chair
Frank Elsner, III
Scott L. Kelley
James J. Lott
J. Emmett Patterson
Marian B. Schultz
Alan J. Stock

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EXECUTIVE COMPENSATION AND EMPLOYEE BENEFITS

        In 2014,2016, ACNB Bank's Chief Risk & Governance Officer provided the Board of Directors with a risk assessment report for the Corporation's incentive compensation programs. The Board of Directors concluded that the programs are balanced, do not motivate imprudent risk taking, and are not reasonably likely to have a material adverse effect on the Corporation.

Summary Compensation Table

        The following table summarizes the total compensation for 2014, 20132016, 2015 and 20122014 for Thomas A. Ritter, the Corporation's President & Chief Executive Officer; David W. Cathell, the Corporation's Executive Vice President, President/Treasurer & Chief Financial Officer; and, the three other persons who were serving as executive officers of the Corporation and/or a subsidiary of the Corporation at the end of 2014.2016. Specifically, these three other persons include Lynda L. Glass, Executive Vice President, President/Secretary & Chief Governance Officer; James P. Helt, President of ACNB Bank; and, Frank C. Russell, Jr., President & Chief Executive Officer of Russell Insurance Group, Inc.; and, James P. Helt, Executive Vice President of Banking Services of ACNB Bank. These individuals are referred to as the Named Executive Officers.

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