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): January 5, 2015 (December 29, 2014)

New Mountain Finance Corporation

(Exact name of registrant as specified in its charter)

787 7th Avenue, 48th Floor, New York, NY 10019

(Address of principal executive offices)

Registrant’s telephone number, including area code (212) 720-0300

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:

Item 1.01.                                  Entry into a Material Definitive Agreement.

On December 29, 2014, New Mountain Finance Corporation (the “Company”) entered into Amendment No. 1 (the “Amendment”) to the Company’s existing senior secured revolving credit facility maturing on June 4, 2019 provided by Goldman Sachs Bank USA as the Administrative Agent and Goldman Sachs Bank USA and Morgan Stanley Bank, N.A. as Lenders (the “NMFC Credit Facility”). The Amendment to the NMFC Credit Facility increased the amount of borrowings available thereunder from $50 million to $80 million.

The description above is only a summary of the material provisions of the Amendment to the NMFC Credit Facility and is qualified in its entirety by reference to the copy of the Amendment which is filed as Exhibit 10.1 to this current report on Form 8-K and is incorporated herein by reference thereto.

Item 2.03                                           Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant.

The disclosure set forth above under Item 1.01 is incorporated by reference herein.

Item 9.01                                           Financial Statements and Exhibits

(a)         Not applicable.

(b)         Not applicable.

(c)          Not applicable.

(d)         Exhibits.

Exhibit No.

10.1                        Amendment No. 1, dated December 29, 2014, to the Senior Secured Revolving Credit Agreement dated June 4, 2014, by and among New Mountain Finance Corporation, as Borrower, and Goldman Sachs Bank USA, as Administrative Agent and Syndication Agent.

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SIGNATURE

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

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