UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C.  20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d)

of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported):  February 28, 2017

ACNB Corporation

(Exact name of Registrant as specified in its charter)

717.334.3161

(Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the Registrant under any of the following provisions (see General Instruction A.2. below):

o Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

o Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

o Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

o Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

CURRENT REPORT ON FORM 8-K

ITEM 5.02           Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers;  Compensatory Arrangements of Certain Officers

On February 28, 2017, Robert W. Miller, a Class 1 Director, submitted his resignation, effective May 2, 2017, from the Boards of Directors of ACNB Corporation (the “Corporation”) and ACNB Bank (the “Bank”), the Corporation’s wholly-owned subsidiary. Mr. Miller has served as a member of the Corporation’s and the Bank’s Boards of Directors since 2007. His resignation is in conjunction with retirement plans in his professional life.

The resignation was not the result of any disagreement with the Corporation or the Bank on any matter relating to their operations, policies or practices.

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this Current Report on Form 8-K to be signed on its behalf by the undersigned, thereunto duly authorized.

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