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): July 28, 2016

Energy XXI Ltd

(Exact name of registrant as specified in its charter)

Canon’s Court, 22 Victoria Street, P.O. Box HM

1179, Hamilton HM EX, Bermuda

(Address of principal executive offices) (Zip Code)

Registrant’s telephone number, including area code (441) 295-2244

(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:

¨ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

¨ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

¨ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

¨ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

As previously reported by Energy XXI Ltd, a Bermuda exempted company (the “Company”), on April 14, 2016, the Company, Energy XXI Gulf Coast, Inc., an indirect wholly-owned subsidiary of the Company (“EGC”), EPL Oil & Gas, Inc., an indirect wholly-owned subsidiary of the Company (“EPL”) and certain other subsidiaries of the Company listed on Schedule 1 of the Restructuring Support Agreement (as defined below) (together with the Company, EGC and EPL, the “Debtors”) filed voluntary petitions for reorganization (the petitions collectively, the “Bankruptcy Petitions”) in the United States Bankruptcy Court for the Southern District of Texas, Houston Division (the “Bankruptcy Court”) seeking relief under the provisions of chapter 11 of Title 11 (“Chapter 11”) of the United States Code (the “Bankruptcy Code”) under the caption In re Energy XXI Ltd, et al., Case No. 16-31928 (the “Chapter 11 Cases”).

Also, as previously reported, prior to filing the Bankruptcy Petitions, on April 11, 2016, the Debtors entered into a Restructuring Support Agreement (as amended, the “Restructuring Support Agreement”) with certain holders (the “Second Lien Noteholders”) of EGC’s 11.000% Senior Secured Second Lien Notes due 2020 (the “Second Lien Notes”), providing that the Second Lien Noteholders party thereto (the “Restructuring Support Parties”) will support a restructuring of the Debtors, subject to the terms and conditions of the Restructuring Support Agreement. On May 16, 2016, the Debtors entered into the First Amendment to the Restructuring Support Agreement by and among the Debtors and the Restructuring Support Parties. On June 28, 2016, the Debtors entered into the Second Amendment to the Restructuring Support Agreement by and among the Debtors and the Restructuring Support Parties.

The Restructuring Support Agreement contains certain milestones for progress in the Chapter 11 Cases (the “Milestones”). On July 28, 2016, the Debtors entered into the Third Amendment to the Restructuring Support Agreement by and among the Debtors and the Restructuring Support Parties (the “Third RSA Amendment”). Pursuant to the Third RSA Amendment, the following Milestones were modified:

The Milestones may be extended further pursuant to a subsequent amendment. A copy of the Third RSA Amendment is attached hereto as Exhibit 10.1 to this Current Report on Form 8-K (this “Form 8-K”). The foregoing description of the Third RSA Amendment is only a summary, does not purport to be complete, and is qualified in its entirety by reference to the Third RSA Amendment.

Cautionary Note Regarding Forward-Looking Statements

This Form 8-K and the related exhibits contain forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. These statements, including those relating to the intent, beliefs, plans or expectations of the Company are based upon current expectations and are subject to a number of risks, uncertainties and assumptions. It is not possible to predict or identify all such factors and the following list should not be considered a complete statement of all potential risks and uncertainties relating to the bankruptcy filing by the Debtors, including, but not limited to: (i) the Company’s ability to obtain Bankruptcy Court approval with respect to motions or other requests made to the Bankruptcy Court in the Chapter 11 Cases, including maintaining strategic control as debtor-in-possession, (ii) the ability of the Company and its subsidiaries to negotiate, develop, confirm and consummate the Plan, (iii) the effects of the Company’s bankruptcy filing on the Company and on the interests of various constituents, (iv) the Bankruptcy Court rulings in the Chapter 11 Cases as well the outcome of all other pending litigation and the outcome of the Chapter 11 Cases in general, (v) the length of time that the Company will operate under Chapter 11 protection and the continued availability of operating capital during the pendency of the proceedings, (vi) risks associated with third party motions in the Chapter 11 Cases, which may interfere with the Company’s ability to confirm and consummate the Plan, (vii) the potential adverse effects of the Chapter 11 proceedings on the Company’s liquidity or results of operations, (viii) increased advisory costs to execute the Company’s reorganization, (ix) the impact of NASDAQ’s delisting on the liquidity and market price of the Company’s common stock and on the Company’s ability to access the public capital markets, (x) the uncertainty that any trading market for the Company’s common stock will exist or develop in the over-the-counter markets, and (xi) other risks and uncertainties. These risks and uncertainties could cause actual results, including project plans and related expenditures and resource recoveries, to differ materially from those described in the forward-looking statements. For a more detailed discussion of risk factors, please see Part I, Item 1A, “Risk Factors” of the Company’s most recent Annual Report on Form 10-K and Part II, Item 1A of the Company’s Quarterly Reports on Form 10-Q for the periods ended September 30, 2015, December 31, 2015 and March 31, 2016 for more information.  The Company assumes no obligation and expressly disclaims any duty to update the information contained herein except as required by law.

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.

Exhibit Index