As filed with the Securities and Exchange Commision on November 13, 2014

Registration No. 333-198559

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

Amendment No. 4
to

FORM S-1
REGISTRATION STATEMENT
UNDER
THE SECURITIES ACT OF 1933

Neff Corporation
(Exact name of registrant as specified in its charter)

3750 N.W. 87^th Avenue, Suite 400
Miami, FL 33178
(305) 513-3350
(Address, including zip code, and telephone number, including area code, of registrant's principal executive offices)

Mark Irion
Chief Financial Officer
Neff Corporation
3750 N.W. 87^th Avenue, Suite 400
Miami, FL 33178
(305) 513-3350
(Name, address, including zip code, and telephone number, including area code, of agent for service)

Approximate date of commencement of proposed sale to the public:
As soon as practicable after the effective date of this registration statement.

         If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, as amended (the "Securities Act"), check the following box.    o

         If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.    o

         If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.    o

         If this Form is a post-effective amendment filed pursuant to Rule 462(d) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.    o

         Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See the definitions of "large accelerated filer," "accelerated filer" and "smaller reporting company" in Rule 12b-2 of the Securities Exchange Act of 1934 (the "Exchange Act"). (Check one):

         The Registrant hereby amends this registration statement on such date or dates as may be necessary to delay its effective date until the Registrant shall file a further amendment which specifically states that this registration statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act, or until this registration statement shall become effective on such date as the Commission, acting pursuant to said Section 8(a), may determine.

EXPLANATORY NOTE

        Neff Corporation is filing this Amendment No. 4 to the registration statement on Form S-1 (File No. 333-198559) solely to submit certain exhibits and restate the list of exhibits set forth in Item 16 of Part II of the registration statement. Accordingly, this amendment consists only of the facing page, this explanatory note and Part II of this registration statement.

PART II
INFORMATION NOT REQUIRED IN PROSPECTUS

Item 13.    Other Expenses of Issuance and Distribution.

        The following table sets forth all expenses to be paid by Neff Corporation, other than underwriting discounts and commissions, upon the completion of this offering. All amounts shown are estimates except for the SEC registration fee, the Financial Industry Regulatory Authority ("FINRA") filing fee and the NYSE listing fee.

Item 14.    Indemnification of Directors and Officers.

        Section 145 of the Delaware General Corporation Law authorizes a corporation's board of directors to grant, and authorizes a court to award, indemnity to officers, directors, and other corporate agents.

        Upon completion of this offering, as permitted by Section 102(b)(7) of the Delaware General Corporation Law, Neff Corporation's amended and restated certificate of incorporation will include provisions that eliminate the personal liability of its directors and officers for monetary damages for breach of their fiduciary duty as directors and officers.

        In addition, as permitted by Section 145 of the Delaware General Corporation Law, the amended and restated certificate of incorporation and amended and restated by-laws of Neff Corporation will provide that:

•

Neff Corporation shall indemnify its directors and officers for serving Neff Corporation in those capacities or for serving other business enterprises at Neff Corporation's request, to the fullest extent permitted by Delaware law. Delaware law provides that a corporation may indemnify such person if such person acted in good faith and in a manner such person reasonably believed to be in or not opposed to the best interests of Neff Corporation and, with respect to any criminal proceeding, had no reasonable cause to believe such person's conduct was unlawful.



•

Neff Corporation may, in its discretion, indemnify employees and agents in those circumstances where indemnification is permitted by applicable law.



•

Neff Corporation is required to advance expenses, as incurred, to its directors and officers in connection with defending a proceeding, except that such director or officer shall undertake to repay such advances if it is ultimately determined that such person is not entitled to indemnification.



•

Neff Corporation will not be obligated pursuant to the amended and restated by-laws to indemnify a person with respect to proceedings initiated by that person, except with respect to proceedings

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authorized by Neff Corporation's board of directors or brought to enforce a right to indemnification.

•

The rights conferred in the amended and restated certificate of incorporation and amended and restated by-laws are not exclusive, and Neff Corporation is authorized to enter into indemnification agreements with its directors, officers, employees, and agents and to obtain insurance to indemnify such persons.



•

Neff Corporation may not retroactively amend the by-law provisions to reduce its indemnification obligations to directors, officers, employees, and agents.

        Neff Corporation's policy is to enter into separate indemnification agreements with each of its directors and officers that provide the maximum indemnity allowed to directors and executive officers by Section 145 of the Delaware General Corporation Law and also to provide for certain additional procedural protections. Neff Corporation also maintains directors and officers insurance to insure such persons against certain liabilities.

        These indemnification provisions and the indemnification agreements entered into between Neff Corporation and its officers and directors may be sufficiently broad to permit indemnification of Neff Corporation's officers and directors for liabilities (including reimbursement of expenses incurred) arising under the Securities Act.

        The underwriting agreement to be filed as Exhibit 1.1 to this registration statement will provide for indemnification by the underwriters of Neff Corporation and Neff Holdings LLC and its officers and directors for certain liabilities arising under the Securities Act and otherwise.

Item 15.    Recent Sales of Unregistered Securities.

        On August 31, 2014, Neff Corporation agreed to issue 100 shares of common stock, par value $0.01 per share, to Wayzata in exchange for $100. The issuance was exempt from registration under Section 4(a)(2) of the Securities Act, as a transaction by an issuer not involving any public offering.

Item 16.    Exhibits and Financial Statement Schedules.

(a)

Exhibits.

        We have filed the exhibits listed on the accompanying Exhibit Index of this Registration Statement.

(b)

Financial Statement Schedules.

        All financial statement schedules are omitted because the information called for is not required or is shown either in the consolidated financial statements or in the notes thereto.

Item 17.    Undertakings.

        The undersigned Neff Corporation hereby undertakes to provide to the underwriters at the closing specified in the underwriting agreement certificates in such denominations and registered in such names as required by the underwriters to permit prompt delivery to each purchaser.

        Insofar as indemnification for liabilities arising under the Securities Act may be permitted to directors, officers, and controlling persons of Neff Corporation pursuant to the foregoing provisions, or otherwise, Neff Corporation has been advised that in the opinion of the SEC such indemnification is against public policy as expressed in the Securities Act and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by Neff Corporation of expenses incurred or paid by a director, officer, or controlling person of Neff Corporation in the successful defense of any action, suit, or proceeding) is asserted by such director, officer, or controlling person in connection with

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the securities being registered, Neff Corporation will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Securities Act and will be governed by the final adjudication of such issue.

        The undersigned Neff Corporation hereby undertakes that:

        (1)   For purposes of determining any liability under the Securities Act, the information omitted from the form of prospectus filed as part of this registration statement in reliance upon Rule 430A and contained in a form of prospectus filed by Neff Corporation pursuant to Rule 424(b)(1) or (4) or 497(h) under the Securities Act shall be deemed to be part of this registration statement as of the time it was declared effective.

        (2)   For the purpose of determining any liability under the Securities Act, each post-effective amendment that contains a form of prospectus shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

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SIGNATURES

        Pursuant to the requirements of the Securities Act of 1933, as amended, Neff Corporation has duly caused this registration statement on Form S-1 to be signed on its behalf by the undersigned, thereunto duly authorized, in New York, New York on the 13th day of November, 2014.

POWER OF ATTORNEY

        KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature appears below hereby constitutes and appoints Graham Hood and Mark Irion, and each of them, as his or her true and lawful attorney-in-fact and agent with full power of substitution, for him or her in any and all capacities, to sign any and all amendments to this registration statement (including post-effective amendments or any abbreviated registration statement and any amendments thereto filed pursuant to Rule 462(b) under the Securities Act of 1933, as amended, increasing the number of securities for which registration is sought), and to file the same, with all exhibits thereto and other documents in connection therewith, with the SEC, granting unto said attorney-in-fact, proxy, and agent full power and authority to do and perform each and every act and thing requisite and necessary to be done in connection therewith, as fully for all intents and purposes as he or she might or could do in person, hereby ratifying and confirming all that said attorney-in-fact, proxy and agent, or his substitute, may lawfully do or cause to be done by virtue hereof.

        Pursuant to the requirements of the Securities Act of 1933, as amended, this registration statement on Form S-1 has been signed by the following persons in the capacities and on the dates indicated.

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EXHIBIT INDEX

QuickLinks

Item 13. Other Expenses of Issuance and Distribution.
Item 14. Indemnification of Directors and Officers.
Item 15. Recent Sales of Unregistered Securities.
Item 16. Exhibits and Financial Statement Schedules.
Item 17. Undertakings.