Exhibit 3.1

CERTIFICATE OF AMENDMENT

OF THE

CERTIFICATE OF INCORPORATION

OF

21ST CENTURY ONCOLOGY HOLDINGS, INC.

(a Delaware corporation)

Pursuant to Section 242 of the General Corporation Law of the State of Delaware, the undersigned officer of 21st Century Oncology Holdings, Inc., a Delaware corporation (the “Corporation”), hereby certifies as follows:

FIRST:                  The name of the Corporation is 21st Century Oncology Holdings, Inc.

SECOND:             The date of filing of the Corporation’s original Certificate of Incorporation was October 9, 2007. The Corporation was originally incorporated under the name Radiation Therapy Services Holdings, Inc.

THIRD:                 The Certificate of Incorporation is hereby amended to effect a change in Article Four thereof. Accordingly, Article Four of the Certificate of Incorporation shall be amended to read as follows:

ARTICLE FOUR

Section 1.              Authorized Shares.  The total number of shares of all classes of capital stock that the Corporation has authority to issue is 4,500,000 shares, consisting of:

(a)           3,500,000 shares of Preferred Stock, par value $0.001 per share (the “Preferred Stock”); and

(b)           1,000,000 shares of Common Stock, par value $0.01 per share (the “Common Stock”).

The Preferred Stock and the Common Stock shall have the rights, preferences and limitations set forth below.

Section 2.              Preferred Stock.  Shares of Preferred Stock may be issued from time to time in one or more series.  The Board of Directors is authorized, to provide by resolution or resolutions from time to time for the issuance, out of the authorized but unissued shares of Preferred Stock, of all or any of the shares of Preferred Stock in one or more series, and to establish the number of shares to be included in each such series, and to fix the voting powers (full, limited or no voting powers), designations, powers, preferences, privileges and relative, participating, optional or other rights, if any, and any qualifications, limitations or restrictions thereof, or such series, including, without limitation, that any such series may be (i) subject to redemption at such time or times and at such price or prices, (ii) entitled to receive dividends (which may be cumulative or non-cumulative) at such rates, on such conditions, and at such times, and payable in preference to, or in such relation to, the dividends payable on any other class or classes or series of capital stock, (iii) entitled to such rights upon the liquidation, dissolution or winding up of, or upon any distribution of the assets of, the Corporation or (iv)

convertible into, or exchangeable for, shares of any other class or classes of capital stock, or of any other series of the same class of capital stock, of the Corporation at such price or prices or at such rates and with such adjustments; all as may be stated in such resolution or resolutions, which resolution or resolutions shall be set forth on a certificate of designations filed with the Secretary of State of the State of Delaware in accordance with the Delaware General Corporation Law.  Except as otherwise provided in this Certificate of Incorporation, no vote of the holders of Preferred Stock or Common Stock shall be a prerequisite to the designation or issuance of any shares of any series of Preferred Stock authorized by and complying with the conditions of this Certificate of Incorporation.  Notwithstanding the provisions of Section 242(b)(2) of the Delaware General Corporation Law, the number of authorized shares of Preferred Stock may be increased or decreased (but not below the number of shares thereof then outstanding) by the affirmative vote of the holders of a majority in voting power of the outstanding shares of capital stock of the Corporation entitled to vote, without the separate vote of the holders of the Preferred Stock as a class.  Subject to Section 1 of this ARTICLE FOUR, the Board of Directors is also expressly authorized to increase or decrease the number of shares of any series of Preferred Stock subsequent to the issuance of shares of that series, but not below the number of shares of such series then outstanding. Unless otherwise expressly provided in the certificate of designations in respect of any series of Preferred Stock, in case the number of shares of such series shall be decreased in accordance with the foregoing sentence, the shares constituting such decrease shall resume the status that they had prior to the adoption of the resolution originally fixing the number of shares of such series.

Section 3.              Common Stock.

(a)           Voting Rights. Except as otherwise provided by the Delaware General Corporation Law or this Certificate of Incorporation and subject to the rights of holders of Preferred Stock, all of the voting power of the stockholders of the Corporation shall be vested in the holders of the Common Stock, and each holder of Common Stock shall have one vote for each share held by such holder on all matters voted upon by the stockholders of the Corporation.  Notwithstanding any other provision of this Certificate of Incorporation to the contrary, the holders of Common Stock shall not be entitled to vote on any amendment to this Certificate of Incorporation (including any certificate of designation in respect of any series of Preferred Stock) that relates solely to the terms of one or more outstanding series of Preferred Stock if the holders of such affected series are entitled, either separate or together as a class with the holders of one or more such other series, to vote thereon pursuant to this Certificate of Incorporation or the Delaware General Corporation Law.

(b)           Dividends. Subject to the rights of the holders of any series of Preferred Stock, and to the other provisions of this Certificate of Incorporation, holders of Common Stock shall be entitled to receive equally, on a per share basis, such dividends and other distributions in cash, securities or other property of the Corporation as may be declared thereon by the Board of Directors from time to time out of assets or funds of the Corporation legally available therefor.

(c)           Liquidation Rights. In the event of any liquidation, dissolution or winding up of the affairs of the Corporation, whether voluntary or involuntary, after payment or provision for payment of the Corporation’s debts and subject to the rights of the holders of shares

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of any series of Preferred Stock upon such dissolution, liquidation or winding up, the remaining net assets of the Corporation shall be distributed among holders of shares of Common Stock equally on a per share basis. A merger or consolidation of the Corporation with or into any other corporation or entity, or a sale, lease, exchange, conveyance or other disposition of all or any part of the assets of the Corporation shall not be deemed to be a voluntary or involuntary liquidation or dissolution or winding up of the Corporation within the meaning of this Section 3(c).

(d)           Conversion Rights. The Common Stock shall not be convertible into, or exchangeable for, shares of any other class or classes or of any other series of the same class of the Corporation’s capital stock

FOURTH:            This amendment to the Certificate of Incorporation of the Corporation effected hereby was approved by the Board of Directors of the Corporation, and by written consent of the stockholders of the issued and outstanding capital stock of the Corporation.

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IN WITNESS WHEREOF, the undersigned affirms as true the foregoing under penalties of perjury, and has executed this Certificate this 25th day of September, 2014.

[Signature Page to Certificate of Amendment of the Certificate of Incorporation]