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): August 29, 2018

CAPSTAR FINANCIAL HOLDINGS, INC.

(Exact name of registrant as specified in its charter)

Registrant’s telephone number, including area code (615) 732-6400

Not Applicable

(Former Name or Former Address, if Changed Since Last Report)

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):

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (17 CFR §230.405) or Rule 12b-2 of the Securities Exchange Act of 1934 (17 CFR §240.12b-2). Emerging growth company  ☒

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.  ☒

A special meeting of shareholders of CapStar Financial Holdings, Inc. (the “Company”) was held on August 29, 2018. The special meeting was held in order to vote upon (1) a proposal to approve the Agreement and Plan of Merger, dated as of June 11, 2018, by and between Athens Bancshares Corporation and the Company (the “Merger Proposal”) and (2) a proposal to adjourn the special meeting, if necessary or appropriate, to solicit additional proxies in favor of the Merger Proposal (the “Adjournment Proposal”). At the special meeting, the Merger Proposal was approved by the affirmative vote of holders of a majority of the outstanding shares of Company common stock entitled to vote on the Merger Proposal. Sufficient votes were also received to approve the Adjournment Proposal, but an adjournment was not necessary in light of the approval of the Merger Proposal.

There were 11,851,724 shares of Company common stock issued and outstanding on the record date and eligible to be voted at the special meeting and 9,431,009 shares represented in person or by proxy at the special meeting, which constituted a quorum to conduct business at the meeting.

The items voted upon at the special meeting and the final voting results for each proposal were as follows:

The merger remains subject to the satisfaction of certain closing conditions, including receipt of regulatory approvals.

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SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

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