UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C.  20549

FORM 8-K/A

CURRENT REPORT

Pursuant to Section 13 or 15(d)

of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported):  May 2, 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))

Indicate by check mark whether the Registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company o

If an emerging growth company, indicate by check mark if the Registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.  o

CURRENT REPORT ON FORM 8-K

Explanatory Note

This Current Report on Form 8-K/A (the “Amendment”) amends and supplements the Current Report on Form 8-K filed by ACNB Corporation (the “Company”) with the Securities and Exchange Commission on May 4, 2017 (the “Original 8-K”).  The sole purpose of this Amendment is to supplement the disclosure in the Original 8-K to disclose the decision regarding how frequently the Company will conduct future non-binding, advisory votes on the Company’s executive compensation programs and practices.

ITEM 5.07           Submission of Matters to a Vote of Security Holders

As previously reported, the Company held its 2017 Annual Meeting of Shareholders on May 2, 2017 (the “Shareholders Meeting”). In the Original 8-K, the Company reported the results of the voting at the Shareholders Meeting, including that the shareholders voted to recommend holding future non-binding, advisory votes on the compensation of the Company’s Named Executive Officers every one (1) year.

In light of the shareholder vote above, the Board of Directors has decided that the Company will include a non-binding shareholder vote on the compensation of executives in the proxy materials annually until the next required vote on the frequency of non-binding shareholder votes on the compensation of executives, which will occur no later than the 2023 Annual Meeting of Shareholders.

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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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