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<CONFORMED-NAME>CALPINE CORP
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<STREET1>50 WEST SAN FERNANDO ST
<CITY>SAN JOSE
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<FILENAME>o31605.txt
<TEXT>
                                  UNITED STATES                  SEC File Number
                       SECURITIES AND EXCHANGE COMMISSION           1-12079
                             Washington, D.C. 20549                 -------
                                                                  Cusip Number
                                   FORM 12b-25

                           NOTIFICATION OF LATE FILING



 (Check One) [x]Form 10-K [ ]Form 20-F [ ]Form 11-K [ ]Form 10-Q [ ]Form N-SAR
 [ ]Form N-CSR

                       For Period Ended: December 31, 2004
                         -------------------------------


                       [ ] Transition Report on Form 10-K
                       [ ] Transition Report on Form 20-F
                       [ ] Transition Report on Form 11-K
                       [ ] Transition Report on Form 10-Q
                       [ ] Transition Report on Form N-SAR
                        For the Transition Period Ended:

  READ INSTRUCTION (ON BACK PAGE) BEFORE PREPARING FORM. PLEASE PRINT OR TYPE.

     Nothing in this form shall be construed to imply that the Commission has
                   verified any information contained herein.

If the notification  relates to a portion of the filing checked above,  identify
the Item(s) to which the notification relates:

                         PART I - REGISTRANT INFORMATION

Calpine Corporation
Full Name of Registrant

Former Name if Applicable

50 West San Fernando Street
Address of Principal Executive Office (STREET AND NUMBER)

San Jose, CA 95113
City, State and Zip Code

                        PART II - RULES 12b-25(b) and (c)

If the subject report could not be filed without  unreasonable effort or expense
and the registrant seeks relief pursuant to Rule 12b-25(b), the following should
be completed. (Check box if appropriate)

[x] (a) The  reasons  described  in  reasonable  detail in Part III of this form
could not be eliminated without unreasonable effort or expense

[x] (b) The subject annual report, semi-annual report, transition report on Form
10-K, Form 20-F, Form 11-K, Form N-SAR or Form N-CSR, or portion  thereof,  will
be filed on or before the fifteenth  calendar day following the  prescribed  due
date;  or the subject  quarterly  report or  transition  report on Form 10-Q, or
portion thereof, will be filed on or before the fifth calendar day following the
prescribed due date; and

[ ] (c) The  accountant's  statement or other exhibit required by Rule 12b-25(c)
has been attached if applicable.

                              PART III - NARRATIVE

State below in reasonable detail why FormS 10-K, 20-F, 11-K, 10-Q, N-SAR, N-CSR,
or the  transition  report or  portion  thereof,  could not be filed  within the
prescribed time period. (Attach Extra Sheets if Needed)

Calpine Corporation is filing this Form 12b-25 with respect to its annual report
on Form 10-K for the year ended  December 31, 2004  because it needs  additional
time to complete its financial statements.  As of December 31, 2004, the Company
did not maintain  effective  controls over the accounting for the tax effects of
its discontinued  operations as a result of the sale of its Canadian and certain
U.S. oil and gas assets  during the third quarter of 2004 and expects to restate
its Form 10-Q for the period ended September 30, 2004 to correct an error in the
tax provision  recorded in that filing.  Due to the additional  time required to
complete these financial  statements,  Calpine could not file its 2004 Form 10-K
in a timely manner without  unreasonable  effort or expense.  Calpine expects to
file its 2004 Form 10-K on or before  March 31,  2005.  As a result of the third
quarter  control  deficiency  with  respect  to the  recording  of taxes  within
discontinued  operations,  management  determined  that this control  deficiency
constitutes a material weakness.  Because of this material weakness, the Company
has concluded that it did not maintain effective internal control over financial
reporting  as of December  31,  2004.  The  Company  expects  that its  external
auditors  will  issue an  adverse  opinion  on the  Company's  internal  control
environment  as of December  31, 2004  because of this issue.  The Company  will
provide a discussion of its  remediation  actions that have been  implemented to
ensure  effective  controls  over the recording of the tax provision in its 2004
Form 10-K. In accordance with Section 404 of the Sarbanes-Oxley Act, the Company
and its auditors  continue to assess the overall  controls  environment  and its
effectiveness.


                           PART IV - OTHER INFORMATION



     (1)  Name and  telephone  number  of person  to  contact  in regard to this
          notification

               Lisa Bodensteiner             408             995-5115
          ---------------------------    -----------    ------------------
                     (Name)              (Area Code)    (Telephone Number)



(2) Have all other  periodic  reports  required under Section 13 or 15(d) of the
Securities  Exchange Act of 1934 or Section 30 of the Investment  Company Act of
1940  during  the  preceding  12  months  or for such  shorter  period  that the
registrant  was  required to file such  report(s)  been filed?  If answer is no,
identify report(s). [x] Yes [ ] No

(3) Is it anticipated that any significant  change in results of operations from
the  corresponding  period for the last  fiscal  year will be  reflected  by the
earnings statements to be included in the subject report or portion thereof?
[x] Yes  [ ] No

If so, attach an explanation of the  anticipated  change,  both  narratively and
quantitatively, and, if appropriate, state the reasons why a reasonable estimate
of the results cannot be made.

                               Calpine Corporation
                               -------------------
                  (Name of Registrant as Specified in Charter)

has  caused  this  notification  to be signed on its  behalf by the  undersigned
hereunto duly authorized.





   Date  March 16, 2005                 By  /s/ Charles B. Clark, Jr.
         -------------------------          ----------------------------
                                            Senior Vice President and Controller
                                            Chief Accounting Officer


INSTRUCTION: The form may be signed by an executive officer of the registrant or
by any other duly  authorized  representative.  The name and title of the person
signing  the form  shall  be typed or  printed  beneath  the  signature.  If the
statement is signed on behalf of the registrant by an authorized  representative
(other than an executive officer), evidence of the representative's authority to
sign on behalf of the registrant shall be filed with the form.

                                    ATTENTION
Intentional  misstatements  or omissions  of fact  constitute  Federal  Criminal
Violations (See 18 U.S.C. 1001).

                               GENERAL INSTRUCTIONS

1. This form is required by Rule 12b-25 (17 CFR 240.12b-25) of the General Rules
and Regulations under the Securities Exchange Act of 1934.

2. One signed  original and four  conformed  copies of this form and  amendments
thereto must be completed and filed with the Securities and Exchange Commission,
Washington,  D.C.  20549 in  accordance  with Rule 0-3 of the General  Rules and
Regulations  under the Act. The information  contained in or filed with the form
will be made a matter of public record in the Commission files.

3. A manually signed copy of the form and amendments thereto shall be filed with
each  national  securities  exchange  on which  any class of  securities  of the
registrant is registered.

4.  Amendments to the  notifications  must also be filed on form 12b-25 but need
not restate  information  that has been correctly  furnished.  The form shall be
clearly identified as an amendment notification.

5. ELECTRONIC FILERS. This form shall not be used by electronic filers unable to
timely file a report  solely due to  electronic  difficulties.  Filers unable to
submit a report  within  the  time  period  prescribed  due to  difficulties  in
electronic  filing  should comply with either Rule 201 or Rule 202 of Regulation
S-T  (Section  232.201  or  Section  232.202  of this  chapter)  or apply for an
adjustment  in filing date  pursuant to Rule 13(b) of  Regulation  S-T  (Section
232.13(b) of this chapter).

                                   ATTACHMENT


The  registrant  anticipates  that  a  significant  change  in  its  results  of
operations  from  the  last  fiscal  year  will  be  reflected  by the  earnings
statements to be included in its 2004 Form 10-K.  Specifically,  the  registrant
expects to report a loss before benefit for income taxes of approximately $717.4
million for 2004,  compared to income before provision for income taxes of $94.6
million  previously  reported  in 2003.  As  discussed  above,  the  Company  is
evaluating  the tax effects for its third quarter 2004  discontinued  operations
and has not  finalized  its 2004 tax  provision.  The 2004  results,  after  the
effects of the  discontinued  operations  from the sale of  certain  oil and gas
assets in September 2004, include several previously disclosed items,  including
a) a $387.9  million  increase in interest  expense and  distributions  on trust
preferred securities,  as compared to the same period in 2003, b) $202.1 million
of  impairment   charges  for  certain  oil  and  gas  reserves  and  c)  market
fundamentals, which caused total spark spread, despite a total increase of $79.2
million,  or 4%, to not increase  commensurately with additional plant operating
expense,  transmission  purchase expense and depreciation  costs associated with
new power plants coming on-line.  These decreases in income before provision for
income  taxes were  partially  offset by pre-tax  income in the amount of $171.5
million,  net of  transaction  costs and the write-off of  unamortized  deferred
financing costs,  associated with the restructuring of power purchase agreements
for the Newark and Parlin power plants and the sale of an entity holding a power
purchase agreement.
</TEXT>
</DOCUMENT>
</SUBMISSION>
