CPN Calpine Corp.

WHERE YOU CAN FIND MORE INFORMATION

As required by the Securities Act of 1933, Citigroup and Citigroup Global Markets Holdings Inc. filed a registration statement relating to the market-making activities of Citigroup’s subsidiaries in the securities referenced on the cover of this prospectus with the Securities and Exchange Commission (“SEC”). This prospectus is a part of that registration statement, which includes additional information.

Citigroup files annual, quarterly and current reports, proxy statements and other information with the SEC. You may read and copy any document Citigroup files at the SEC’s public reference room in Washington, D.C. You can also request copies of the documents, upon payment of a duplicating fee, by writing the Public Reference Section of the SEC. Please call the SEC at 1-800-SEC-0330 for further information on the public reference room. These SEC filings are also available to the public from the SEC’s web site at http://www.sec.gov.

The SEC allows Citigroup to “incorporate by reference” the information it files with the SEC, which means that it can disclose important information to you by referring you to those documents. The information incorporated by reference is considered to be part of this prospectus. Information that Citigroup files later with the SEC will automatically update information in this prospectus. In all cases, you should rely on the later

information over different information included in this prospectus. Citigroup incorporates by reference the documents listed below and any future filings made with the SEC under Section 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934 (File No. 1-09924):

In no event, however, will any of the information that Citigroup furnishes to, pursuant to Item 2.02 or Item 7.01 of any Current Report on Form 8-K (including exhibits related thereto) or other applicable SEC rules, rather than files with, the SEC be incorporated by reference or otherwise be included herein, unless such information is expressly incorporated herein by a reference in such furnished Current Report on Form 8-K or other furnished document.

All documents filed by Citigroup specified in Section 13(a), 13(c), 14 or 15(d) of the Exchange Act after the date of this prospectus and before the date the broker-dealer subsidiaries of Citigroup stop offering securities pursuant to this prospectus shall be incorporated by reference in this prospectus from the date of filing of such documents.

You may request a copy of these filings, at no cost, by writing or telephoning Citigroup at the following address:

Citigroup Document Services

540 Crosspoint Parkway

Getzville, NY 14068

(716) 730-8055 (tel.)

(877) 936-2737 (toll free)

You should rely only on the information provided in this prospectus and the pricing supplement, if any, product supplement, if any, prospectus supplement, if any, and prospectus describing the terms of the specific securities being offered and sold in the secondary market, as well as the information incorporated by reference. Neither Citigroup nor Citigroup Global Markets Holdings Inc. nor any broker-dealer subsidiary of Citigroup is making an offer of any of the securities referenced on the cover of this prospectus in any jurisdiction where the offer is not permitted. You should not assume that the information in this prospectus, any applicable pricing supplement, any applicable product supplement, any applicable prospectus supplement and the prospectus or any documents incorporated by reference is accurate as of any date other than the date of the applicable document.

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