UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION        SEC File Number
                             WASHINGTON, DC 20549                001-16077

                                   FORM 12b-25
                           NOTIFICATION OF LATE FILING

(Check One):   [X] Form 10-K [ ] Form 11-K [ ] Form 20-F [ ] Form 10-Q
               [ ] Form N-SAR
               For Period Ended: December 31, 2002

               [ ] 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:

     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

Full name of registrant:                    Orion Power Holdings, Inc.
Former name if applicable:                  Not Applicable
Address of principal executive office
(Street and number):                        c/o Reliant Resouces, Inc.
                                            1111 Louisiana Street
City, state and zip code                    Houston, Texas 77002

                                     PART II
                             RULE 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.)

     |    (a)  The reasons described in reasonable detail in Part III of this
     |         form could not be eliminated without unreasonable effort or
     |         expense;
     |
     |    (b)  The subject annual report, semi-annual report, transition report
     |         on Form 10-K, 20-F, 11-K or Form N-SAR, or portion thereof, will
[X]  |         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 the reasons why Forms 10-K, 11-K, 20-F,
10-Q, N-SAR, or the transition report portion thereof, could not be filed within
the prescribed time period:



     The registrant's parent company, Reliant Resources, Inc., is attempting to
complete the refinancing of its $1.6 billion senior revolving credit facilities,
$2.9 billion 364-day acquisition term loan, and $1.425 billion construction
agency financing commitment. The registrant's Annual Report on Form 10-K cannot
be filed within the prescribed time period, without unreasonable effort or
expense, because neither the registrant's consolidated financial statements at
and for the year ended December 31, 2002 nor the narrative portions of the
registrants' Annual Report on Form 10-K have been completed. The registrant is
in the process of updating and completing all such disclosures to appropriately
reflect the registrant's refinancing efforts and anticipates that its Annual
Report on Form 10-K will be filed before the 15th calendar day following its
prescribed due date.

                                     PART IV
                                OTHER INFORMATION

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

          Curtis A. Morgan         (713)                 497-3000
                (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 the 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.

For a discussion of significant changes in the registrant's 2002 results of
operations as compared to its 2001 results of operations, please read the
registrant's Quarterly Report on Form 10-Q for the period ended September 30,
2002 which is incorporated herein by reference.

                           Orion Power Holdings, Inc.
                        --------------------------------
                  (Name of Registrant as Specified in Charter)

Has caused this notification to be signed on its behalf by the undersigned
thereunto duly authorized.

Date:    March 31, 2003                  By:    /s/ Curtis A. Morgan
      ------------------                   ------------------------------------
                                                    Curtis A. Morgan
                                                       President