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 30, 2013 (August 28, 2013)

RADIATION THERAPY SERVICES

HOLDINGS, INC.

(Exact Name of Registrant as Specified in Charter)

Delaware

(State or Other Jurisdiction of Incorporation)

(239) 931-7275

(Registrant’s Telephone Number, including Area Code)

N/A

(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):

Item 1.01                                           Entry into a Material Definitive Agreement.

On August 28, 2013, Radiation Therapy Services, Inc. (“RTS”), a wholly owned subsidiary of Radiation Therapy Services Holdings, Inc. (the “Company”), the Company, the subsidiaries of RTS identified therein, the lenders signatory thereto and Wells Fargo Bank, National Association, as administrative agent and collateral agent, entered into an Amendment Agreement (the “Amendment Agreement”) to the credit agreement among RTS, the Company, the institutions from time to time party thereto as lenders, the Administrative Agent named therein and the other agents and arrangers named therein, dated as of May 10, 2012 (the “Original Credit Agreement” and, as amended and restated by the Amendment Agreement, the “Credit Agreement”).  Pursuant to the terms of the Amendment Agreement the amendments to the Original Credit Agreement became effective on August 29, 2013.

The Credit Agreement provides for credit facilities consisting of (i) a $90 million term loan facility (the “Term Facility”) and (ii) a revolving credit facility provided for up to $100 million of revolving extensions of credit outstanding at any time (including revolving loans, swingline loans and letters of credit) (the “Revolving Credit Facility” and together with the Term Facility, the “Credit Facilities”).  The Term Facility and the Revolving Credit Facility each have a maturity date of October 15, 2016.

Loans under the Revolving Credit Facility and the Term Facility are subject to the following interest rates:

(a) for loans which are Eurodollar loans, for any interest period, at a rate per annum equal to (i) a floating index rate per annum equal to (A) the rate per annum determined on the basis of the rate for deposits in dollars for a period equal to such interest period commencing on the first day of such interest period appearing on Reuters Screen LIBOR01 Page as of 11:00 A.M., London time, two business days prior to the beginning of such interest period divided by (B) 1.0 minus the then stated maximum rate of all reserve requirements applicable to any member bank of the Federal Reserve System in respect of eurocurrency funding or liabilities as defined in Regulation D (or any successor category of liabilities under Regulation D) (provided that solely with respect to loans under the Term Facility, such floating index rate shall not be less than 1.00% per annum), plus (ii) an applicable margin (A) based upon a total leverage pricing grid for loans under the Revolving Credit Facility or (B) equal to 6.50% per annum for loans under the Term Facility; and

(b) for loans which are base rate loans, at a rate per annum equal to (i) a floating index rate per annum equal to the greatest of (A) the Administrative Agent’s prime lending rate at such time, (B) the overnight federal funds rate at such time plus ½ of 1%, and (C) the Eurodollar Rate for a Eurodollar loan with a one-month interest period commencing on such day plus 1.00% (provided that solely with respect to loans under the Term Facility, such floating index rate shall not be less than 2.00% per annum), plus (ii) an applicable margin (A) based upon a total leverage pricing grid for loans under the Revolving Credit Facility or (B) equal to 5.50% per annum for loans under the Term Facility.

RTS will pay certain recurring fees with respect to the Credit Facilities, including (i) fees on the unused commitments of the lenders under the Revolving Credit Facility, (ii) letter of credit fees on the aggregate face amounts of outstanding letters of credit and (iii) administration fees.

The Credit Agreement contains customary representations and warranties, subject to limitations and exceptions, and customary covenants restricting the ability (subject to various exceptions) of RTS and certain of its subsidiaries to:  incur additional indebtedness (including guarantee obligations); incur liens; engage in mergers or other fundamental changes; sell certain property or assets; pay dividends of other distributions; consummate acquisitions; make investments, loans and advances; prepay certain indebtedness, change the nature of their business; engage in certain transactions with affiliates; and incur restrictions on the ability of RTS’s subsidiaries to make distributions, advances and asset transfers.  In addition, as of the last business day of each month, RTS will be required to maintain a certain minimum amount of unrestricted cash and cash equivalents plus availability under the Revolving Credit Facility.

The Credit Agreement contains customary events of default, including with respect to nonpayment of principal, interest, fees or other amounts; material inaccuracy of a representation or warranty when made; failure to perform or observe covenants; cross default to other material indebtedness; bankruptcy and insolvency events; inability to pay debts; monetary judgment defaults; actual or asserted invalidity or impairment of any definitive loan documentation and a change of control.

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The obligations of RTS under the Credit Facilities are guaranteed by the Company and certain direct and indirect wholly-owned domestic subsidiaries of RTS.

The Credit Facilities and certain interest rate protection and other hedging arrangements provided by lenders under the Credit Facilities or its affiliates are secured on a first priority basis by security interests in substantially all of RTS’s and each guarantor’s tangible and intangible assets (subject to certain exceptions).

The foregoing description of the Amendment Agreement is qualified in its entirety by reference to such agreement, a copy of which is attached hereto as Exhibit 10.1, and incorporated into this item 1.01 by reference.

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

The description of the Amendment Agreement included in Item 1.01 of this Current Report on Form 8-K is incorporated by reference into this Item 2.03 of this Current Report on Form 8-K.

Item 8.01                                           Other Events.

On August 29, 2013, the Company issued a press release announcing its entry into the Amendment Agreement, a copy of which is attached hereto as Exhibit 99.1, and incorporated herein by reference.

Forward-Looking Statements

This Current Report on Form 8-K contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended.  Statements preceded by, followed by or that otherwise include the words “believes”, “expects”, “anticipates”, “intends”, “projects”, “estimates”, “plans”, “may increase”, “forecast” and similar expressions or future or conditional verbs such as “will”, “should”, “would”, “may” and “could” are generally forward-looking in nature and not historical facts. Forward-looking statements are based on management’s current expectations or beliefs about the Company’s future plans, expectations and objectives.  These forward-looking statements are not historical facts and are subject to risks and uncertainties that could cause the actual results to differ materially from those projected in these forward-looking statements including, but not limited to reductions in Medicare reimbursement, healthcare reform, decreases in payments by managed care organizations and other commercial payers and other risk factors that may be described from time to time in the Company’s filings with the Securities and Exchange Commission.  Readers of this release are cautioned not to place undue reliance on forward-looking statements contained herein, which speak only as of the date stated, or if no date is stated, as of the date of this Current Report. The Company undertakes no obligation to publicly update or revise the forward-looking statements contained herein to reflect changed events or circumstances after the date of this release, unless required by law.

Item 9.01                                           Financial Statements and Exhibits.

(d)                                 Exhibits.

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SIGNATURES

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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EXHIBIT INDEX

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