UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC 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):  September 5, 2013

MainSource Financial Group, Inc.

(Exact name of registrant as specified in its charter)

2105 N. State Road 3 Bypass

Greensburg, Indiana 47240

(Address of principal executive offices) (Zip Code)

Registrant’s telephone number, including area code:  (812) 663-6734

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 240.425)

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))

Item 7.01 Regulation FD Disclosure

On September 5, 2013, MainSource Financial Group, Inc.’s wholly owned bank subsidiary, MainSource Bank (“MainSource Bank”), announced that it entered into a Branch Purchase and Assumption Agreement (the “Agreement”) with Old National Bank (“ONB”) to purchase certain assets from ONB, including ONB’s branch in Hope, Indiana.  The purchase includes the existing branch location at 8475 North State Road 9 in Hope, Indiana, as well as approximately $4 million in loans and approximately $25 million in deposits.  Also included in the agreement are the deposits associated with ONB’s Greensburg, Indiana branch office.  Subject to the receipt of regulatory approvals and the satisfaction of customary closing conditions, the transaction is expected to close in December of 2013.

Attached hereto as Exhibit 99.1 is a press release issued by MainSource Bank announcing the branch purchase which is incorporated herein by reference pursuant to General Instruction F to Form 8-K.

Forward-Looking Statements

Except for historical information contained herein, the discussion in this Report may include certain forward looking statements based upon management expectations.  Actual results and experience could differ materially from the anticipated results or other expectations expressed in the Company’s forward-looking statements.  Factors which could cause future results to differ from these expectations include the following: general economic conditions; legislative and regulatory initiatives; monetary and fiscal policies of the federal government; deposit flows; the cost of funds; general market rates of interest; interest rates on competing investments; demand for loan products; demand for financial services; changes in accounting policies or guidelines; changes in the quality or composition of the Company’s loan and investment portfolios; the Company’s ability to integrate acquisitions; the impact of our continuing acquisition strategy; and other factors, including various “risk factors” as set forth in our most recent annual report on Form 10-K and in other reports we file from time to time with the Securities and Exchange Commission.  These reports are available publicly on the SEC website, www.sec.gov, and on the Company’s website, www.mainsourcefinancial.com.

Item 9.01.                                        Financial Statements and Exhibits.

(d)                                 Exhibits.

99.1                        Press Release Issued by MainSource Bank dated September 5, 2013.

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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.

Date:  September 5, 2013

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EXHIBIT INDEX

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