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): March 8, 2012

COVANTA HOLDING CORPORATION

(Exact name of registrant as specified in its charter)

Registrant’s telephone number, including area code: (862) 345-5000

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:

Item 1.01. Entry into a Material Definitive Agreement.

On March 8, 2012, Covanta Holding Corporation (the “Company”) entered into an Underwriting Agreement (the “Underwriting Agreement”) with Morgan Stanley & Co. LLC and Merrill Lynch, Pierce, Fenner & Smith Incorporated as representatives and on behalf of the several underwriters named therein (collectively, the “Underwriters”) providing for the offer and sale by the Company of $400 million principal amount of 6.375% Senior Notes due 2022 (the “Notes”).

The offering of the Notes was registered under the Securities Act of 1933 and is being made pursuant to the Company’s Registration Statement on Form S-3, Reg. No. 333-178503 and the prospectus dated December 15, 2011 included therein, filed by the Company with the Securities and Exchange Commission on December 15, 2011, as supplemented by the preliminary prospectus supplement relating thereto dated March 8, 2012, and the final prospectus supplement relating thereto dated March 8, 2012.

The Underwriting Agreement includes customary representations, warranties and covenants by the Company. It also provides for customary indemnification by each of the Company and the Underwriters against certain liabilities arising out of or in connection with the sale of the Notes and customary contribution provisions in respect of those liabilities. The closing of the offering, which is subject to customary closing conditions, is expected to occur on March 19 2012.

The foregoing description of the material terms of the Underwriting Agreement is qualified in its entirety by reference to the Underwriting Agreement, which is attached hereto as Exhibit 1.1 and is incorporated herein by reference.

Item 9.01. Financial Statements and Exhibits.

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 thereunto duly authorized.

Date: March 8, 2012

COVANTA HOLDING CORPORATION

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