BHP Billiton (BHP)

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 20-F/A

Amendment No. 1

(Mark One)

OR

FOR THE FISCAL YEAR ENDED 30 JUNE 2010

OR

OR

Date of event requiring this shell company report:             

Securities registered or to be registered pursuant to Section 12(g) of the Act: None

Securities for which there is a reporting obligation pursuant to Section 15(d) of the Act: None

Indicate the number of outstanding shares of each of the issuer’s classes of capital or common stock as of the close of the period covered by the annual report.

Indicate by check mark if the registrants are well-known seasoned issuers, as defined in rule 405 of the Securities Act.    Yes  x    No  ¨

If this report is an annual or transition report, indicated by check mark if the registrants are not required to file reports pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934.    Yes  ¨    No  x

Note – Checking the box above will not relieve any registrant requiring to file reports pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 from their obligations under those Sections.

Indicate by check mark whether the registrants: (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.    Yes  x    No  ¨

Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Web site, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T (§ 232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files).    Yes  ¨    No  ¨

Indicate by check mark whether the registrants are large accelerated filers, accelerated filers, or non-accelerated filers. See definition of “accelerated filer and large accelerated filer” in Rule 12b-2 of the Exchange Act. (Check one):

Large accelerated filer  x    Accelerated filer  ¨    Non-accelerated filer  ¨

Indicate by check mark which basis of accounting the registrants has used to prepare the financial statements included in this filing:

US GAAP  ¨    International Financial  reporting Standards as issued by the International Accounting Standards Board  x    Other  ¨

If “Other” has been checked in response to the previous question, indicate by check mark which financial statement item the registrants have elected to follow:    Item 17  ¨    Item 18  ¨

If this is an annual report, indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).    Yes  ¨    No  x

This Amendment No. 1 to Form 20-F is being filed solely to the Annual Report on Form 20-F for the fiscal year ended June 30, 2010, filed jointly by BHP Billiton Limited and BHP Billiton Plc on September 21, 2010, (the “Form 20-F”) in order to refile Exhibit 4.11. Exhibit 4.11 is an Implementation Agreement which has been entered into by BHP Billiton Limited, BHP Billiton Plc, Rio Tinto Limited and Rio Tinto plc dated December 5, 2009 (including the schedules thereto) (collectively, the “Implementation Agreement”). As announced in the report on Form 6-K filed with the Securities and Exchange Commission by BHP Billiton Limited and BHP Billiton Plc on October 26, 2010, the plans for a joint venture between the parties have ended and the Implementation Agreement has been terminated.

Portions of Exhibit 4.11 were redacted and filed separately with the Securities Exchange Commission pursuant to a request for confidential treatment. The purpose of this Amendment No. 1 to Form 20-F is to replace Exhibit 4.11 with a new version which includes the names of the signatories to the Implementation Agreement. Exhibit 4.11 to this Amendment No. 1 to Form 20-F supersedes and replaces the corresponding exhibit originally filed with the Form 20-F. Certain other portions of this new version of Exhibit 4.11 will continue to be redacted and filed separately with the Securities and Exchange Commission pursuant to a request for confidential treatment.

This Amendment No. 1 to Form 20-F, including revised Exhibit 4.11, speaks as of the date of the initial filing of the Form 20-F. Other than as described above, this Amendment No. 1 to Form 20-F does not, and does not purport to, amend, update or restate the information in the Form 20-F or reflect any events that have occurred after the Form 20-F was filed.

12 Exhibits

The registrants hereby certify that they meet all of requirements for filing on Form 20-F/A and that they have duly caused and authorized the undersigned to sign this Amendment No. 1 to the Annual Report on their behalf.

Date: December 22, 2010