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): April 17, 2012

UNITED RENTALS, INC.

UNITED RENTALS (NORTH AMERICA), INC.

(Exact name of registrant as specified in its charter)

Registrant’s telephone number, including area code: (203) 622-3131

(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:

On April 17, 2012, United Rentals, Inc. (the “Company”), issued a press release reporting its results of operations for the quarter ended March 31, 2012. A copy of the press release is being furnished with this report as Exhibit 99.1.

Certain information concerning our business, financial results and 2012 outlook that we expect to use at certain investor meetings and presentations can be accessed currently on our website, www.ur.com. Such presentation will be maintained on our website for at least the period of its use at such meetings and presentations or until superseded by more current information.

The presentation includes certain financial measures—free cash flow, earnings before interest, taxes, depreciation and amortization (“EBITDA”), adjusted EBITDA and adjusted earnings per share (“EPS”)—that are “non-GAAP financial measures” as defined under the rules of the Securities and Exchange Commission. Free cash flow represents net cash provided by operating activities, less purchases of rental and non-rental equipment plus proceeds from sales of rental and non-rental equipment and excess tax benefits from share-based payment arrangements, net. EBITDA represents the sum of net income (loss), provision (benefit) for income taxes, interest expense, net, interest expense-subordinated convertible debentures, net, depreciation of rental equipment and non-rental depreciation and amortization. Adjusted EBITDA represents EBITDA plus the sum of the RSC merger related costs, the restructuring charge and stock compensation expense, net. Adjusted EPS represents EPS plus the sum of the RSC merger related costs, restructuring charge, loss on the retirement of subordinated convertible debentures and RSC merger related interest expense.

The presentation includes reconciliations of these non-GAAP financial measures to their nearest generally accepted accounting principles financial measures. The Company believes that: (i) free cash flow provides useful additional information concerning cash flow available to meet future debt service obligations and working capital requirements; (ii) EBITDA and adjusted EBITDA provide useful information about operating performance and period-over-period growth and (iii) adjusted EPS provides useful information concerning future profitability. However, none of these measures should be considered as alternatives to net income, cash flows from operating activities or earnings per share under GAAP as indicators of operating performance or liquidity.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, each registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

Date: April 17, 2012

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