UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-K/A

AMENDMENT NO. 1

TO

ANNUAL REPORT UNDER SECTION 13 OR 15(d)

OF THE SECURITIES EXCHANGE ACT OF 1934

For the fiscal year ended December 31, 2008

Commission File Number: 001-16715

FIRST CITIZENS BANCSHARES, INC.

(Exact name of Registrant as specified in its charter)

4300 Six Forks Road

Raleigh, North Carolina 27609

(Address of Principal Executive Offices, Zip Code)

(919) 716-7000

(Registrant’s Telephone Number, including Area Code)

Securities registered under:

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act.    Yes  x    No  ¨

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act.     Yes  ¨    No  x

Indicate by check mark whether the Registrant (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 twelve 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 ninety days.    Yes  x    No  ¨

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K is not contained herein, and will not be contained, to the best of Registrant’s knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K.  ¨

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 definition of “large accelerated filer,” “accelerated filer,” “non-accelerated filer,” and “smaller reporting company” in Rule 12b-2 of the Exchange Act.

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).    Yes  ¨    No  x

The aggregate market value of the Registrant’s common equity held by nonaffiliates computed by reference to the price at which the common equity was last sold as of the last business day of the Registrant’s most recently completed second fiscal quarter was $718,318,286 as of June 30, 2008.

On February 27, 2009, there were 8,756,778 outstanding shares of the Registrant’s Class A Common Stock and 1,677,675 outstanding shares of the Registrant’s Class B Common Stock.

Portions of the Registrant’s definitive Proxy Statement for the 2009 Annual Meeting of Shareholders are incorporated in Part III of this report.

EXPLANATORY NOTE

The purpose of this Form 10-K/A is to amend the original Annual Report on Form 10-K for the fiscal year ended December 31, 2008 (the “2008 Form 10-K”) of First Citizens BancShares, Inc. (the “Company”) filed with the Securities and Exchange Commission (the “SEC”) on February 27, 2009, by:

(1) correcting the Company’s SEC file number on the report cover; and

(2) revising the certifications of the Company’s principal executive officer and principal financial officer required by Rule 13a-14(b) under the Securities Exchange Act of 1934, as amended (the “Exchange Act”) which were filed as Exhibit 32 to the 2008 Form 10-K.

In addition, as required by Rule 12b-15 under the Exchange Act, new certifications of the Company’s principal executive officer and principal financial officer required by Rule 13a-14(a) of the Exchange Act are filed as exhibits to this Form 10-K/A.

Except as stated herein, no other revisions are being made in the Company’s 2008 Form 10-K.

This Form 10-K/A does not reflect events occurring after the filing of the Company’s 2008 Form 10-K on February 27, 2009, and no attempt has been made in this Form 10-K/A to modify or update other disclosures as presented in the 2008 Form 10-K. Accordingly, this Form 10-K/A should be read in conjunction with the Company’s filings with the SEC subsequent to the filing of the 2008 Form 10-K.

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CROSS REFERENCE INDEX

PART IV    Item 15    Exhibits, Financial Statements and Schedules.

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SIGNATURES

In accordance with Section 13 or 15(d) of the Securities Exchange Act of 1934, the Company has caused this Amendment No. 1 to its Annual Report on Form 10-K/A to be signed on its behalf by the undersigned, thereunto duly authorized.

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EXHIBIT INDEX