UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

(Rule 14a-101)

INFORMATION REQUIRED IN PROXY STATEMENT

SCHEDULE 14A INFORMATION

Proxy Statement Pursuant To Section 14(a) of the

Securities Exchange Act of 1934 (Amendment No.)

Filed by the Registrant  x

Filed by a Party other than the Registrant  ¨

Check the appropriate box:

¨ Preliminary Proxy Statement

¨ Confidential, for use of the Commission only (as permitted by Rule 14a-6(e)(2))

¨ Definitive Proxy Statement

x Definitive additional materials

¨ Soliciting material under Rule 14a-12

CALPINE CORPORATION

(Name of Registrant as Specified in Charter)

Not applicable

(Name of Person(s) Filing Proxy Statement, if Other than the Registrant)

Payment of filing fee (Check the appropriate box):

x No fee required.

¨ Fee computed on the table below per Exchange Act Rules 14a-6(i)(1) and 0-11.

(1) Title of each class of securities to which transaction applies:

(2) Aggregate number of securities to which transaction applies:

(3) Per unit price or other underlying value of transaction computed pursuant to Exchange Act Rule 0-11:

(4) Proposed maximum aggregate value of transaction:

(5) Total fee paid:

¨ Fee paid previously with preliminary materials.

¨ Check box if any part of the fee is offset as provided by Exchange Act Rule 0-11(a)(2) and identify the filing for which the offsetting fee was paid previously. Identify the previous filing by registration statement number, or the Form or Schedule and the date of its filing.

(1) Amount Previously paid:

(2) Form, Schedule or Registration Statement No.:

(3) Filing Party:

(4) Date Filed:

*** Exercise Your Right to Vote ***

IMPORTANT NOTICE Regarding the Availability of Proxy Materials

CALPINE CORPORATION

Meeting Information
Meeting Type:	Annual
For holders as of:	March 22, 2010
Date: May 19, 2010	Time: 10:00 a.m. Central Time
Location:	The Magnolia Hotel 1100 Texas Avenue Houston, Texas 77002

You are receiving this communication because you hold shares in Calpine Corporation.

This is not a ballot. You cannot use this notice to vote these shares. This communication presents only an overview of the more complete proxy materials that are available to you on the Internet. You may view the proxy materials online at www.proxyvote.com or easily request a paper copy (see reverse side).

We encourage you to access and review all of the important information contained in the proxy materials before voting.

See the reverse side of this notice to obtain proxy materials and voting instructions.

— Before You Vote —

How to Access the Proxy Materials

Proxy Materials Available to VIEW or RECEIVE:

NOTICE AND PROXY STATEMENT            ANNUAL REPORT

How to View Online:

Have the 12-Digit Control Number available (located on the following page) and visit: www.proxyvote.com

How to Request and Receive a PAPER or E-MAIL Copy:

If you want to receive a paper or e-mail copy of these documents, you must request one. There is NO charge for requesting a copy. Please choose one of the following methods to make your request:

1) BY INTERNET:	www.proxyvote.com
2) BY TELEPHONE:	1-800-579-1639
3) BY E-MAIL*:	sendmaterial@proxyvote.com

* If requesting materials by e-mail, please send a blank e-mail with the 12-Digit Control Number (located on the following page) in the subject line.

Requests, instructions and other inquiries sent to this e-mail address will NOT be forwarded to your investment advisor. Please make the request as instructed above on or before May 5, 2010 to facilitate timely delivery.

— How To Vote —

Please Choose One of the Following Voting Methods

Vote In Person: Many shareholder meetings have attendance requirements including, but not limited to, the possession of an attendance ticket issued by the entity holding the meeting. Please check the meeting materials for any special requirements for meeting attendance. At the Meeting you will need to request a ballot to vote these shares.

Vote By Internet: To vote now by Internet, go to www.proxyvote.com. Have the 12-Digit Control Number available (located on the following page) and follow the instructions.

Vote By Mail: You can vote by mail by requesting a paper copy of the materials, which will include a proxy card.

Voting Items

THE BOARD OF DIRECTORS RECOMMENDS THAT YOU VOTE FOR THE FOLLOWING:

1. ELECTION OF DIRECTORS

Nominees:
01) Frank Cassidy	06) Robert A. Mosbacher, Jr.
02) Jack A. Fusco	07) Denise M. O’Leary
03) Robert C. Hinckley	08) William J. Patterson
04) David C. Merritt	09) J. Stuart Ryan
05) W. Benjamin Moreland

THE BOARD OF DIRECTORS RECOMMENDS A VOTE “FOR” THE FOLLOWING PROPOSALS:

2. Ratification of PricewaterhouseCoopers LLP as the Company’s independent registered public accountants for the year ending December 31, 2010.

3. Amendment of the 2008 Director Incentive Plan.

4. Amendment of the 2008 Equity Incentive Plan.

NOTE: If any other matters properly come before the meeting or any adjournment thereof, the Proxies will vote in their discretion.