UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549
                               ___________________

                                   FORM 10-K/A

     [X]  ANNUAL  REPORT  PURSUANT  TO  SECTION  13 OR 15(d)  OF THE  SECURITIES
          EXCHANGE ACT OF 1934 For the Fiscal Year Ended December 31, 2001

                                                                  OR

     [ ]  TRANSITION  REPORT  PURSUANT TO SECTION 13 OR 15(d) OF THE  SECURITIES
          EXCHANGE ACT OF 1934




Commission File            Name of Registrant; State of Incorporation; Address of       IRS Employer
Number                     Principal Executive Offices; and Telephone Number            Identification Number
---------------------      ---------------------------------------------------------    -------------------------
                                                                                  
1-16169                    EXELON CORPORATION                                           23-2990190
                           (a Pennsylvania corporation)
                           10 South Dearborn Street - 37th Floor
                           P.O. Box 805379
                           Chicago, Illinois 60680-5379
                           (312) 394-4321


Securities registered pursuant to Section 12(b) of the Act:

                                                                                    Name of Each Exchange on
Title of Each Class                                                                 Which Registered
------------------------------------------------------------------------------      -----------------------------
EXELON CORPORATION:
     Common Stock, without par value                                                New York, Chicago and
                                                                                    Philadelphia


         Indicate  by check  mark  whether  the  registrants  (1) have filed all
reports  required to be filed by Section 13 or 15(d) of the Securities  Exchange
Act of 1934 during the preceding 12 months (or for such shorter  period that the
registrant was required to file such reports), and (2) have been subject to such
filing requirements for the past 90 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  registrants'  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. [ ]

         The  estimated  aggregate  market  value of the voting  and  non-voting
common  equity  held by  nonaffiliates  of  Exelon as of March 1,  2002,  was as
follows:

         Exelon Corporation Common Stock, without par value     $15,839,570,208

         The number of shares  outstanding of Exelon's  common stock as of March
1, 2002 was as follows:

         Exelon Corporation Common Stock, without par value        321,419,850


                                       i





                      DOCUMENTS INCORPORATED BY REFERENCE:

         Portions of Exelon Corporation's (Exelon) Current Report on Form 8-K/A
dated October 30, 2002 containing consolidated financial statements and related
information for the year ended December 31, 2001, are incorporated by reference
into Parts II and IV of this Annual Report on Form 10-K/A.

Explanatory Note

         This amendment to Exelon Corporation's Annual report on Form 10-K for
the period ended December 31, 2001 reflects a restatement as a result of a $101
million double posting of deferred income taxes recorded associated with
unrealized losses on Exelon Generation Company, LLC's (Generation) nuclear
decommissioning trust fund securities. Additionally, Exelon and Generation
determined that Other Comprehensive Income should be restated for the amount of
$27 million to reflect Generation's ownership interest in the Other
Comprehensive Income of its equity investments in AmerGen Energy Company, LLC
and Sithe Energies Inc. Earnings per share, net income and cash flow for the
periods are not affected by the restatements. However, Other Comprehensive
Income, which is a component of Shareholders' Equity, will be reduced by a total
of approximately $128 million as of December 31, 2001 as a result of the
revision. See Note 2. No attempt has been made in this Form 10-K/A to modify or
update other disclosures as presented in the original Form 10-K except as
required to reflect the effects of the restatements.










                                       ii



                                TABLE OF CONTENTS


                                                                     Page No.
FORWARD LOOKING STATEMENTS                                               1

PART II
     ITEM 6.      SELECTED FINANCIAL DATA                                2
     ITEM 8.      FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA            2

PART IV
     ITEM 14.     EXHIBITS, FINANCIAL STATEMENT SCHEDULES, AND
                           REPORTS ON FORM 8-K                           3

SIGNATURES                                                              15

CERTIFICATIONS                                                          16


                                       iv



                           FORWARD-LOOKING STATEMENTS

         Except for the historical  information contained herein, certain of the
matters discussed in this Report are forward-looking statements that are subject
to risks and  uncertainties.  The  factors  that could cause  actual  results to
differ  materially  from the  forward-looking  statements  made by a  registrant
include  those  discussed  herein as well as those  listed in Note 8 of Notes to
Consolidated Financial Statements,  those discussed in "Management's  Discussion
and  Analysis of  Financial  Condition  and Results of  Operations--Outlook"  in
Exelon  Corporation's  2001 Annual Report,  those discussed in "Risk Factors" in
PECO Energy Company's  Registration  Statement on Form S-3, Reg. No.  333-99361,
those discussed in "Risk Factors" and  "Management's  Discussion and Analysis of
Financial  Condition and Results of  Operations" in Exelon  Generation  Company,
LLC's  Registration  Statement on Form S-4, Reg. No. 333-85496 and other factors
discussed  in  filings  with  the  Securities  and  Exchange  Commission  by the
Registrants.  Readers  are  cautioned  not to  place  undue  reliance  on  these
forward-looking statements, which apply only as of the date of this Report. None
of the Registrants  undertake any obligation to publicly release any revision to
its forward-looking statements to reflect events or circumstances after the date
of this Report.








                                       1



                                     PART II


ITEM 6.  SELECTED FINANCIAL DATA.

Exelon

         The  information  required  by this  Item  is  incorporated  herein  by
reference  to  "Selected  Financial  Data" in Exhibit  99-1 to Exelon's  Current
Report on Form 8-K/A dated October 30, 2002.


ITEM 8.  FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA

Exelon

         The  information  required  by this  Item  is  incorporated  herein  by
reference to the Consolidated  Statements of Income for the years 2001, 2000 and
1999;  Consolidated  Statements of Cash Flows for the years 2001, 2000 and 1999;
Consolidated  Balance  Sheets as of  December  31,  2001 and 2000;  Consolidated
Statements of Changes in Shareholders'  Equity for the years 2001, 2000 and 1999
and Consolidated Statements of Comprehensive Income for the years 2001, 2000 and
1999; and Notes to Consolidated  Financial  Statements appearing in Exhibit 99-2
to Exelon's Current Report on Form 8-K/A dated October 30, 2002.


                                     PART IV

ITEM 14. EXHIBITS, FINANCIAL STATEMENT SCHEDULES, AND REPORTS ON FORM 8-K

                      Report of Independent Accountants on
                          Financial Statement Schedule

To the Shareholders and Board of Directors
 of Exelon Corporation:

Our audits of the consolidated  financial  statements  referred to in our report
dated January 29, 2002,  except for Note 25 for which the date is March 1, 2002,
appearing in the 2001 Annual Report to Shareholders of Exelon Corporation (which
report and  consolidated  financial  statements are incorporated by reference in
this  Annual  Report  on Form  10-K)  also  included  an audit of the  financial
statement  schedule  listed  in Item  14(a)(1)(ii)  of this  Form  10-K.  In our
opinion,  this financial  statement  schedule  presents fairly,  in all material
respects,  the information  set forth therein when read in conjunction  with the
related consolidated financial statements.

PricewaterhouseCoopers LLP

Chicago, Illinois
January 29, 2002


                                       2




(a) Financial Statements and Financial Statement Schedules

          (1)  Exelon

               (i)  Financial Statements

                    Consolidated Statements of Income for the years 2001, 2000
                    and 1999

                    Consolidated Statements of Cash Flows for the years 2001,
                    2000 and 1999

                    Consolidated Balance Sheets as of December 31, 2001 and 2000

                    Consolidated Statements of Changes in Shareholders' Equity
                    for the years 2001, 2000 and 1999

                    Consolidated Statements of Comprehensive Income for the
                    years 2001, 2000 and 1999

                    Notes to Consolidated Financial Statements

               (ii) Financial Statement Schedule






                                       3


                              EXELON CORPORATION AND SUBSIDIARY COMPANIES




                            Schedule II - Valuation and Qualifying Accounts
                                             (in millions)

Column A                                    Column B                Column C     Column D         Column E
--------                                    --------                --------     --------         --------
                                                                   Additions
                                                       ---------------------
                                                        Charged
                                          Balance at    to Cost      Charged
                                           Beginning        and     to Other                    Balance at
Description                                  of Year   Expenses     Accounts    Deductions     End of Year
----------------------------------------------------------------------------------------------------------

For The Year Ended December 31, 2001
------------------------------------
                                                                                     
Allowance for Uncollectible Accounts           $ 200       $145         $ --         $132(a)        $  213

Reserve for:
    Merger-Related Costs                       $ 144       $ --         $ 41         $  71          $  114

    Injuries and Damages                       $  69       $ 17         $  2         $  16(b)       $   72

    Environmental Investigation and
      Remediation                              $ 171       $  1         $ --         $  16(c)       $  156

    Obsolete Materials                         $ 103       $ 16         $ --         $ 101          $   18

For The Year Ended December 31, 2000
------------------------------------

Allowance for Uncollectible Accounts           $ 112       $ 87         $ 59(d)      $  58(a)       $  200

Reserve for:
    Merger-Related Costs                       $  --       $ --         $149(e)      $   5          $  144

    Injuries and Damages                       $  23       $  9         $ 48(f)      $  11(b)       $   69

    Environmental Investigation and
      Remediation                              $  57       $ 26         $ 98(e)      $  10(c)       $  171

    Obsolete Materials                         $  --       $ 48         $ 55(e)      $   3          $  100

For The Year Ended December 31, 1999
------------------------------------

Allowance for Uncollectible Accounts           $ 122       $ 59         $ --         $  69(a)       $  112

Reserve for:
    Injuries and Damages                       $  27       $  7         $ --         $  11(b)       $   23

    Environmental Investigation and
      Remediation                              $  60       $ --         $ --         $   3(c)       $   57
----------------------------------------------------------------------------------------------------------

(a)  Write-off of individual accounts receivable.
(b)  Payments of claims and related costs.
(c)  Expenditures for site investigation and remediation.
(d)  Includes October 20, 2000 opening balance of former Unicom Corporation of
     $48 .
(e)  Reflects October 20, 2000 opening balance of former Unicom Corporation .
(f)  Reflects October 20, 2000 opening balance of former Unicom Corporation of
     $47 million.




                                                  4



                  The individual  financial statements and schedules of Exelon's
         nonconsolidated  wholly owned subsidiaries have been omitted from their
         respective  Annual Reports on Form 10-K/A because the  investments  are
         not  material in relation to their  respective  financial  positions or
         results of  operations.  As of  December  31,  2001,  the assets of the
         nonconsolidated  subsidiaries,  in the aggregate,  were less than 1% of
         Exelon's  consolidated assets. The 2001 revenues of the nonconsolidated
         subsidiaries,   in  the  aggregate,  were  less  than  1%  of  Exelon's
         consolidated annual revenues.

          (b)  Reports on Form 8-K

               (1)  Exelon

                  Exelon filed Current Reports on Form 8-K during the fourth
         quarter of 2001 regarding the following items:

         Date of  Earliest
         Event Reported             Description of Item Reported
         ----------------------------------------------------------------------
         October 23, 2001      "ITEM 5. OTHER EVENTS" regarding Exelon's
                               earnings release for the third quarter of 2001.

         October 23, 2001      "ITEM 9. REGULATION FD DISCLOSURE" regarding
                               highlights and clarifications of the Exelon Third
                               Quarter Earnings Conference Call.

         October 29, 2001      "ITEM 9. REGULATION FD DISCLOSURE" regarding a
                               presentation by John W. Rowe, Co-CEO and
                               President of Exelon, at the Edison Electric
                               Institute Conference. The exhibits under "ITEM 7.
                               FINANCIAL STATEMENTS AND EXHIBITS" include the
                               slide presentation and additional information.

         November 28, 2001     "ITEM 9. REGULATION FD DISCLOSURE" regarding a
                               press release issued by Exelon disclosing its
                               direct net exposure to Enron.

         December 20, 2001     "ITEM 5. OTHER EVENTS" regarding the announcement
                               by Exelon of its intention to purchase two
                               generating plants from TXU Corp. and "ITEM 9.
                               REGULATION FD DISCLOSURE" regarding additional
                               information related to the acquisition.

(c)      Exhibits

         Certain of the following exhibits are incorporated  herein by reference
under Rule  12b-32 of the  Securities  and  Exchange  Act of 1934,  as  amended.
Certain other  instruments  which would otherwise be required to be listed below
have not been so listed because such instruments do not authorize  securities in
an amount which exceeds 10% of the total assets of the applicable registrant and
its subsidiaries on a consolidated  basis and the relevant  registrant agrees to
furnish a copy of any such instrument to the Commission upon request.




                                       5


Exhibit No.         Description
------------------- ------------------------------------------------------------

2-1                 Amended and Restated Agreement and Plan of Merger dated as
                    of October 20, 2000, among PECO Energy Company, Exelon
                    Corporation and Unicom Corporation (File No. 1-01401, PECO
                    Energy Company Form 10-Q for the quarter ended September 30,
                    2000, Exhibit 2-1)

3-1                 Articles of Incorporation of Exelon Corporation
                    (Registration Statement No. 333-37082, Form S-4, Exhibit
                    3-1).

3-2                 Bylaws of Exelon Corporation (Registration Statement No.
                    333-37082, Form S-4, Exhibit 3-2).

3-3                 Amended and Restated Articles of Incorporation of PECO
                    Energy Company (File No. 1-1401, 2000 Form 10-K, Exhibit
                    3-3).

3-4                 Bylaws of PECO Energy Company, adopted February 26, 1990 and
                    amended January 26, 1998 (File No. 1-01401, 1997 Form 10-K,
                    Exhibit 3-2).

3-5                 Restated  Articles of Incorporation  of Commonwealth  Edison
                    Company effective February 20, 1985, including Statements of
                    Resolution    Establishing    Series,    relating   to   the
                    establishment  of three new  series of  Commonwealth  Edison
                    Company  preference  stock  known as the  "$9.00  Cumulative
                    Preference Stock," the "$6.875 Cumulative  Preference Stock"
                    and the  "$2.425  Cumulative  Preference  Stock"  (File  No.
                    1-1839, 1994 Form 10-K, Exhibit 3-2).

3-6                 Bylaws of Commonwealth  Edison Company,  effective September
                    2,  1998,  as amended  through  October  20,  2000 (File No.
                    1-1839, 2000 Form 10-K, Exhibit 3-6).

4-1                 364-day Credit Agreement, dated as of December 12, 2001,
                    among Exelon Corporation, Commonwealth Edison Company, PECO
                    Energy Company and Exelon Generation, LLC as Borrowers,
                    certain banks named therein as Lenders, Bank One, N.A., as
                    Administrative Agent, ABN AMRO Bank, N.V. and Barclays Bank
                    plc, as Co-documentation Agents, Citibank, N.A. and First
                    Union National Bank, as Co-syndication Agents and Banc One
                    Capital Markets, Inc., as Lead Arranger and Sole Book
                    Runner.

4-2                 First and Refunding Mortgage dated May 1, 1923 between The
                    Counties Gas and Electric Company (predecessor to PECO
                    Energy Company) and Fidelity Trust Company, Trustee (First
                    Union National Bank, successor), (Registration No. 2-2281,
                    Exhibit B-1).

4-2-1               Supplemental Indentures to PECO Energy Company's First and
                    Refunding Mortgage:



                    Dated as of                   File Reference                         Exhibit No.
                    ----------------------------- -------------------------------------- --------------------
                                                                                  
                    May 1, 1927                   2-2881                                 B-1(c)
                    March 1, 1937                 2-2881                                 B-1(g)
                    December 1, 1941              2-4863                                 B-1(h)
                    November 1, 1944              2-5472                                 B-1(i)



                                       6


                    December 1, 1946              2-6821                                 7-1(j)
                    September 1, 1957             2-13562                                2(b)-17
                    May 1, 1958                   2-14020                                2(b)-18
                    March 1, 1968                 2-34051                                2(b)-24
                    March 1, 1981                 2-72802                                4-46
                    March 1, 1981                 2-72802                                4-47
                    December 1, 1984              1-01401, 1984 Form 10-K                4-2(b)
                    April 1, 1991                 1-01401, 1991 Form 10-K                4(e)-76
                    December 1, 1991              1-01401, 1991 Form 10-K                4(e)-77
                    April 1, 1992                 1-01401, March 31, 1992                4(e)-79
                                                  Form 10-Q
                    June 1, 1992                  1-01401, June 30, 1992                 4(e)-81
                                                  Form 10-Q
                    July 15, 1992                 1-01401, June 30, 1992                 4(e)-83
                                                  Form 10-Q
                    September 1, 1992             1-01401, 1992 Form 10-K                4(e)-85
                    March 1, 1993                 1-01401, 1992 Form 10-K                4(e)-86
                    May 1, 1993                   1-01401, March 31, 1993                4(e)-88
                                                  Form 10-Q
                    May 1, 1993                   1-01401, March 31, 1993                4(e)-89
                                                  Form 10-Q
                    August 15, 1993               1-01401, Form 8-A dated                4(e)-92
                                                  August 19, 1993

                    May 1, 1995                   1-01401, Form 8-K dated                4(e)-96
                                                  May 24, 1995
                    October 15, 2001              1-01401, Form 10-K dated               4-2-1
                                                  April 1, 2002


4-3                 Exelon Corporation Dividend Reinvestment and Stock Purchase
                    Plan.(Registration Statement No. 333-84446, Form S-3,
                    Prospectus)

4-4                 Mortgage  of   Commonwealth   Edison   Company  to  Illinois
                    Merchants Trust Company, Trustee (BNY Midwest Trust Company,
                    as  current  successor  Trustee),  dated  July 1,  1923,  as
                    supplemented and amended by Supplemental  Indenture  thereto
                    dated August 1, 1944.  (File No. 2-60201,  Form S-7, Exhibit
                    2-1).



                                       7


4-4-1               Supplemental Indentures to aforementioned Commonwealth
                    Edison Mortgage.



                    Dated as of                   File Reference                Exhibit No.
                    ----------------------------- ----------------------------- -----------------
                                                                        
                    August 1, 1946                2-60201, Form S-7             2-1
                    April 1, 1953                 2-60201, Form S-7             2-1
                    March 31, 1967                2-60201, Form S-7             2-1
                    April 1,1967                  2-60201, Form S-7             2-1
                    February 28, 1969             2-60201, Form S-7             2-1
                    May 29, 1970                  2-60201, Form S-7             2-1
                    June 1, 1971                  2-60201, Form S-7             2-1
                    April 1, 1972                 2-60201, Form S-7             2-1
                    May 31, 1972                  2-60201, Form S-7             2-1
                    June 15, 1973                 2-60201, Form S-7             2-1
                    May 31, 1974                  2-60201, Form S-7             2-1
                    June 13, 1975                 2-60201, Form S-7             2-1
                    May 28, 1976                  2-60201, Form S-7             2-1
                    June 3, 1977                  2-60201, Form S-7             2-1
                    May 17, 1978                  2-99665, Form S-3             4-3
                    August 31, 1978               2-99665, Form S-3             4-3
                    June 18, 1979                 2-99665, Form S-3             4-3
                    June 20, 1980                 2-99665, Form S-3             4-3
                    April 16, 1981                2-99665, Form S-3             4-3
                    April 30, 1982                2-99665, Form S-3             4-3
                    April 15, 1983                2-99665, Form S-3             4-3
                    April 13, 1984                2-99665, Form S-3             4-3
                    April 15, 1985                2-99665, Form S-3             4-3
                    April 15, 1986                33-6879, Form S-3             4-9
                    June 15, 1990                 33-38232, Form S-3            4-12
                    June 1, 1991                  33-40018, Form S-3            4-12
                    October 1, 1991               33-40018, Form S-3            4-13
                    October 15, 1991              33-40018, Form S-3            4-14
                    February 1, 1992              1-1839, 1991 Form 10-K        4-18
                    May 15, 1992                  33-48542, Form S-3            4-14
                    July 15, 1992                 33-53766, Form S-3            4-13
                    September 15, 1992            33-53766, Form S-3            4-14
                    February 1, 1993              1-1839, 1992 Form 10-K        4-14
                    April 1, 1993                 33-64028, Form S-3            4-12
                    April 15, 1993                33-64028, Form S-3            4-13
                    June 15, 1993                 1-1839,  Form 8-K  dated May  4-1
                                                  21, 1993
                    July 15, 1993                 1-1839,    Form   10-Q   for  4-1
                                                  quarter ended June 30, 1993.
                    January 15, 1994              1-1839, 1993 Form 10-K        4-15
                    December 1, 1994              1-1839, 1994 Form 10-K        4-16
                    June 1, 1996                  1-1839, 1996 Form 10-K        4-16
                    March 1, 2002                 1-1839, 2001 Form 10-K        4-4-1


4-4-2               Instrument of Resignation,  Appointment and Acceptance dated
                    as of  February  20,  2002,  under  the  provisions  of  the
                    Mortgage  dated July 1, 1923,  and  Indentures  Supplemental
                    thereto, regarding corporate trustee.


                                       8


4-4-3               Instrument   dated  as  of  January  31,  1996,   under  the
                    provisions of the Mortgage dated July 1, 1923 and Indentures
                    Supplemental thereto, regarding individual trustee (File No.
                    1-1839, 1995 Form 10-K, Exhibit 4-29).

4-5                 Indenture dated as of September 1, 1987 between Commonwealth
                    Edison Company and Citibank, N.A., Trustee relating to Notes
                    (File No. 1-1839, Form S-3, Exhibit 4-13).

4-6-1               Supplemental Indentures to aforementioned Indenture.



                    Dated as of                   File Reference                Exhibit No.
                    ----------------------------- ----------------------------- -----------------------------
                                                                         
                    September 1, 1987             33-32929, Form S-3            4-16
                    January 1, 1997               1-1839, 1999 Form 10-K        4-21
                    September 1, 2000             1-1839, 2000 Form 10-K        4-7-3


10-1                Stock Purchase Agreement among Exelon (Fossil) Holdings,
                    Inc., as Buyer and The Stockholders of Sithe Energies, Inc.,
                    as Sellers, and Sithe Energies, Inc. (File No. 0-16844, PECO
                    Energy Company Form 10-Q for the quarter ended September 30,
                    2000, Exhibit 10-1).

10-2                Amended and restated  employment  agreement  between  Exelon
                    Corporation and John W. Rowe dated as of November 26, 2001.*

10-3                Exelon Corporation Deferred Compensation. (File No. 1-16169,
                    2001 Form 10-K, Exhibit 10-3)

10-4                Exelon Corporation Retirement Program. (File No. 1-16169,
                    2001 Form 10-K, Exhibit 10-4)

10-5                PECO Energy Company Unfunded Deferred Compensation Plan for
                    Directors* (Registration Statement No. 333-49780, Form S-8,
                    Exhibit 4-4).

10-6                Exelon Corporation  Long-Term  Incentive Plan As Amended and
                    Restated  effective  January 28,  2002 * (File No.  1-16169,
                    Exelon Proxy Statement dated March 13, 2002, Appendix B).

10-6-1              Forms of Restricted Stock Award Agreement under the Exelon
                    Corporation Long-Term Incentive Plan.* (File No. 1-16169,
                    2001 Form 10-K, Exhibit 10-6-1)

10-6-2              Forms of transferable Stock Option Award Agreement under the
                    Exelon Corporation Long-Term Incentive Plan *

10-6-3              Forms of non-transferable Stock Option Award Agreement under
                    the Exelon Corporation Long-Term Incentive Plan.* (File No.
                    1-16169, 2001 Form 10-K, Exhibit 10-6-3)

10-7                PECO Energy Company Management Incentive Compensation Plan
                    *(File No. 1-01401, 1997 Proxy Statement, Appendix A).



                                       9


10-8                PECO Energy Company 1998 Stock Option Plan *(Registration
                    Statement No. 333-37082, Post-Effective Amendment No. 1 to
                    Form S-4, Exhibit 4-3).

10-9                Exelon Corporation Employee Savings Plan (File No. 1-16169,
                    2001 Form 10-K, Exhibit 10-9)

10-10               Second Amended and Restated Trust  Agreement for PECO Energy
                    Transition Trust (File No. 333-58055, PECO Energy Transition
                    Trust Report on Form 8-K dated May 2, 2000, Exhibit 4.1).

10-11               Indenture  dated as of March 1,  1999  between  PECO  Energy
                    Transition  Trust  and  The  Bank  of New  York.  (File  No.
                    333-58055,  PECO Energy  Transition Trust Report on Form 8-K
                    dated March 25, 1999, Exhibit 4.3.1).

10-11-1             Series  Supplement  dated as of March 25, 1999  between PECO
                    Energy  Transition Trust and The Bank of New York. (File No.
                    333-58055,  PECO Energy  Transition Trust Report on Form 8-K
                    dated March 25, 1999, Exhibit 4.3.2).

10-11-2             Series  Supplement  dated as of March 1, 2001  between  PECO
                    Energy  Transition Trust and The Bank of New York. (File No.
                    333-58055,  PECO Energy  Transition Trust Report on Form 8-K
                    dated March 1, 2001, Exhibit 4.3.2).

10-11-3             Series  Supplement  dated  as of May 2,  2000  between  PECO
                    Energy  Transition  Trust and The Bank of New York (File No.
                    333-58055,  PECO Energy  Transition Trust Report on Form 8-K
                    dated May 2, 2000, Exhibit 4.3.2).

10-12               Intangible  Transition  Property Sale Agreement  dated as of
                    March  25,1999,  as amended and  restated as of May 2, 2000,
                    between  PECO  Energy   Transition  Trust  and  PECO  Energy
                    Company.  (File No. 333-58055,  PECO Energy Transition Trust
                    Report on Form 8-K dated May 2, 2000, Exhibit 10.1).

10-12-1             Amendment  No.  1 to  Intangible  Transition  Property  Sale
                    Agreement  dated  as of  March  25,  1999,  as  amended  and
                    restated  as of May 2, 2000 (File No.  1-01401,  PECO Energy
                    Company and PECO Energy  Transition Trust Report on Form 8-K
                    dated March 1, 2001).

10-13               Master  Servicing  Agreement  dated as of March 25, 1999, as
                    amended and restated as of May 2, 2000,  between PECO Energy
                    Transition   Trust  and  PECO  Energy  Company.   (File  No.
                    333-58055,  PECO Energy  Transition  Trust Current Report on
                    Form 8-K dated May 2, 2000, Exhibit 10.2).

10-13-1             Amendment No. 1 to Master  Servicing  Agreement  dated as of
                    March 25,  1999,  as amended and  restated as of May 2, 2000
                    (File No.  1-01401,  PECO  Energy  Company  and PECO  Energy
                    Transition Trust Report on Form 8-K dated March 1, 2001).

10-14               Exelon Corporation Cash Balance Pension Plan.



                                       10


10-15               Joint Petition for Full Settlement of PECO Energy  Company's
                    Restructuring Plan and Related Appeals and Application for a
                    Qualified  Rate  Order  and   Application  for  Transfer  of
                    Generation  Assets  dated  April  29,  1998.   (Registration
                    Statement No. 333-58055, Exhibit 10.3).

10-16               Joint Petition for Full Settlement of PECO Energy  Company's
                    Application  for  Issuance  of  Qualified  Rate Order  Under
                    Section 2812 of the Public  Utility Code dated March 8, 2000
                    (Amendment No. 1 to  Registration  Statement No.  333-31646,
                    Exhibit 10.4).

10-17               Unicom Corporation  Amended and Restated Long-Term Incentive
                    Plan *(File No. 1-11375,  Unicom Proxy Statement dated April
                    7, 1999, Exhibit A).

10-17-1             First Amendment to Unicom  Corporation  Amended and Restated
                    Long  Term  Incentive  Plan  *(Registration   Statement  No.
                    333-49780, Form S-8, Exhibit 4-8).

10-17-2             Second Amendment to Unicom Corporation  Amended and Restated
                    Long  Term  Incentive  Plan  *(Registration   Statement  No.
                    333-49780, Form S-8, Exhibit 4-9).

10-18               Unicom Corporation General Provisions Regarding 1996 Stock
                    Option Awards Granted under the Unicom Corporation and
                    Long-Term Incentive Plan. *(File Nos. 1-11375 and 1-1839,
                    1996 Form 10-K, Exhibit 10-9).

10-19               Unicom Corporation General Provisions Regarding 1996B Stock
                    Option Awards Granted under the Unicom Corporation Long-Term
                    Incentive Plan. *(File Nos. 1-11375 and 1-1839, 1996 Form
                    10-K, Exhibit 10-8).

10-20               Unicom Corporation General Provisions Regarding Stock Option
                    Awards  Granted  under  the  Unicom  Corporation   Long-Term
                    Incentive Plan (Effective July 10, 1997) (File Nos.  1-11375
                    and 1-1839, 1999 Form 10-K, Exhibit 10-8).

10-21               Unicom Corporation Deferred Compensation Unit Plan, as
                    amended *(File Nos. 1-11375 and 1-1839, 1995 Form 10-K,
                    Exhibit 10-12).

10-22               Exelon Corporation Corporate Stock Referral Plan.* (File No.
                    1-16169, 2001 Form 10-K, Exhibit 10-22)

10-23               Unicom Corporation Retirement Plan for Directors, as amended
                    *(Registration Statement No. 333-49780, Form S-8, Exhibit
                    4-12).

10-24               Commonwealth Edison Company Retirement Plan for Directors,
                    as amended *(Registration Statement No. 333-49780, Form S-8,
                    Exhibit 4-13).

10-25               Unicom  Corporation  1996  Directors'  Fee Plan  *(File  No.
                    1-11375,   Unicom  Proxy  Statement  dated  April  8,  1996,
                    Appendix A).

10-25-1             Second  Amendment to Unicom  Corporation  1996 Directors Fee
                    Plan  *(Registration  Statement  No.  333-49780,  Form  S-8,
                    Exhibit 4-11).


                                       11


10-26               Employment Agreement dated November 1, 1997 between
                    Commonwealth Edison Company and Oliver D. Kingsley, Jr.
                    (File Nos. 1-11375 and 1-1839, 1998 Form 10-K, Exhibit
                    10-22).

10-27               Change in  Control  Agreement  between  Unicom  Corporation,
                    Commonwealth  Edison Company and certain senior executives *
                    (File Nos.  1-11375  and  1-1839,  1998 Form  10-K,  Exhibit
                    10-24).

10-27-1             Forms of Change in Control  Agreement  Between  PECO  Energy
                    Company and Certain Employees * (File No. 1-1401,  2000 Form
                    10-K, Exhibit 10-25-1).

10-28               Commonwealth Edison Company Executive Group Life Insurance
                    Plan *(File No. 1-1839, 1980 Form 10-K, Exhibit 10-3).

10-28-1             Amendment to the Commonwealth Edison Company Executive Group
                    Life Insurance Plan *(File No. 1-1839, 1981 Form 10K,
                    Exhibit 10-4).

10-28-2             Amendment to the Commonwealth Edison Company Executive Group
                    Life Insurance Plan dated December 12, 1986 *(File No.
                    1-1839, 1986 Form 10-K, Exhibit 10-6).

10-28-3             Amendment to the Commonwealth Edison Company Executive Group
                    Life  Insurance  Plan to implement  program of "split dollar
                    life  insurance"  dated December 13, 1990 *(File No. 1-1839,
                    1990 Form 10-K, Exhibit 10-10).

10-28-4             Amendment to  Commonwealth  Edison Company  Executive  Group
                    Life   Insurance   Plan  to  stabilize   the  death  benefit
                    applicable  to  participants  dated July 22, 1992 *(File No.
                    1-1839, 1992 Form 10-K, Exhibit 10-13).

10-29               First Amendment to Exelon Corporation Employee Savings Plan.
                    (File No. 1-16169, 2001 Form 10-K, Exhibit 10-29)

10-29-1             First Amendment to the Commonwealth Edison Company
                    Supplemental Management Retirement Plan. * (File No. 1-1839,
                    2000 Form 10-K, Exhibit 10-27-1)

10-30               Second Amendment and Restated Exelon Corporation Key
                    Management Severance Plan. * (File No. 1-16169, 2001 Form
                    10-K, Exhibit 10-30)

10-31               Forms of Change in Control Agreement between Exelon
                    Corporation and certain senior executives. (File No.
                    1-16169, 2001 Form 10-K, Exhibit 10-31)

10-32               Amendment No. 1 to Exelon Corporation Supplemental Executive
                    Retirement Plan. * (File No. 1-16169, 2001 Form 10-K,
                    Exhibit 10-32)

10-33               Form of Stock Award Agreement under the Unicom Corporation
                    Long-Term Incentive Plan *(File Nos. 1-11375 and 1-1839,
                    1997 Form 10-K, Exhibit 10-37).



                                       12


10-34               Amended  and  Restated  Key  Management  Severance  Plan for
                    Unicom  Corporation  and  Commonwealth  Edison Company dated
                    March 8, 1999 * (File No.  1-1839,  1999 Form 10-K,  Exhibit
                    10-38).

10-34-1             Exelon Corporation Employee Stock Purchase Plan
                    (Registration Statement No. 333-61390, Form S-8, Exhibit
                    4.2).

10-34-2             First Amendment to the Exelon Corporation Employee Stock
                    Purchase Plan. (File No. 1-16169, 2001 Form 10-K, Exhibit
                    10-34-2)

10-35               PECO Energy Company  Supplemental  Pension  Benefit Plan (As
                    Amended and Restated January 1, 2001).*

10-36               Exelon Corporation 2001 Performance Share Awards for Power
                    Team Employees under the Exelon Corporation Long Term
                    Incentive Plan. * (File No. 1-16169, 2001 Form 10-K, Exhibit
                    10-36)

16                  Arthur Andersen Letter to Securities and Exchange Commission
                    regarding the change in certifying accountant (File No.
                    1-01839, Exelon Corporation Report on Form 8-K dated
                    November 28, 2000, Exhibit 16).

18-1                Letter from  PricewaterhouseCoopers  LLP addressed to Exelon
                    Corporation  concerning  a change in  accounting  principles
                    (File No. 1-16169, 2000 Form 10-K, Exhibit 18-1).

18-2                Letter from PricewaterhouseCoopers LLP addressed to PECO
                    Energy Company concerning a change in accounting principles
                    (File No. 1-1401, 2000 Form 10-K, Exhibit 10-30-1).

21                  Subsidiaries

                    21-1 Exelon Corporation (File No. 1-16169, 2001 Form 10-K,
                         Exhibit 21-1)

23                  Consent of Independent Accountants

                    23-1 Exelon Corporation


99-1                Exelon Corporation's Current Report on Form 8-K/A dated
                    October 30, 2002, File No. 1-16169.


                                       13





Certifications  Pursuant to Section 1350 of Chapter 63 of Title 18 United States
Code  (Sarbanes  - Oxley Act of 2002) as to the  amended  annual  report on Form
8-K/A for the period ended December 31, 2001 filed by the following officers for
Exelon Corporation:
--------------------------------------------------------------------------------
99-2              Filed by John W. Rowe
99-3              Filed by Ruth Ann M. Gillis

--------------------------------------------------------------------------------
*  Compensatory  plan or  arrangements  in which  directors  or  officers of the
applicable registrant participate and which are not available to all employees.



                                       14



SIGNATURES

         Pursuant to the  requirements  of Section 13 or 15(d) of the Securities
Exchange Act of 1934, the registrant has duly caused this report to be signed on
its behalf by the undersigned, thereunto duly authorized, in the City of Chicago
and State of Illinois on the 30th day of October, 2002.

                              EXELON CORPORATION

                              By: /S/ John W. Rowe
                                  ---------------------------
                              Name:  John W. Rowe
                              Title:  President and Co-Chief Executive Officer

         Pursuant to the  requirements  of the Securities  Exchange Act of 1934,
this report has been signed by the following persons on behalf of the registrant
and in the capacities indicated on the 30th day of October, 2002.

  Signature                          Title



/S/ John W. Rowe           President and Co-Chief Executive Officer and Director
John W. Rowe               (Co-Chief Executive Officer)

/S/ Ruth Ann M. Gillis     Senior Vice President and Chief Financial Officer
Ruth Ann M. Gillis         (Principal Financial and Accounting Officer)

This  annual  report has also been  signed  below by John W. Rowe and Randall E.
Mehrberg,  Attorneys-in-Fact,  on behalf of the following  Directors on the date
indicated:

                  EDWARD A. BRENNAN                       RICHARD H. GLANTON
                  CARLOS H. CANTU                         ROSEMARIE B. GRECO
                  DANIEL L. COOPER                        EDGAR D. JANNOTTA
                  M. WALTER D'ALESSIO                     JOHN M. PALMS, PH.D.
                  BRUCE DEMARS                            JOHN W. ROGERS, JR.
                  G. FRED DIBONA, JR.                     RONALD RUBIN
                  SUE L. GIN                              RICHARD L. THOMAS

By:  /S/ John W. Rowe                                    October 30, 2002
     -------------------------------
Name:  John W. Rowe
Title:  President and Co-Chief Executive Officer

By:  /S/ Randall E. Mehrberg                             October 30, 2002
     -------------------------------
Name:  Randall E. Mehrberg
Title:  Senior Vice President and General Counsel





                                       15



                                 CERTIFICATIONS
--------------------------------------------------------------------------------

     Certification Pursuant to Rule 13a-14 and 15d-14 of the Securities and
                              Exchange Act of 1934


I, John W. Rowe certify that:


1. I have reviewed this amended report on Form 10-K/A of Exelon Corporation;


2. Based on my knowledge, this report does not contain any untrue statement of a
material fact or omit to state a material fact  necessary to make the statements
made, in light of the  circumstances  under which such statements were made, not
misleading with respect to the period covered by this amended report;


3.  Based  on my  knowledge,  the  financial  statements,  and  other  financial
information included in this report, fairly present in all material respects the
financial  condition,  results of operations and cash flows of the registrant as
of, and for, the periods presented in this amended report;


Date: October 30, 2002


                                /s/ John W. Rowe
                          ----------------------------
                                  John W. Rowe
                                Chairman and CEO



                                       16






     Certification Pursuant to Rule 13a-14 and 15d-14 of the Securities and
                              Exchange Act of 1934
--------------------------------------------------------------------------------




I, Ruth Ann M. Gillis certify that:


1. I have reviewed this amended report on Form10-K/A of Exelon Corporation;


2. Based on my knowledge, this report does not contain any untrue statement of a
material fact or omit to state a material fact  necessary to make the statements
made, in light of the  circumstances  under which such statements were made, not
misleading with respect to the period covered by this report;


3.  Based  on my  knowledge,  the  financial  statements,  and  other  financial
information  included in this  amended  report,  fairly  present in all material
respects the financial  condition,  results of operations  and cash flows of the
registrant as of, and for, the periods presented in this amended report;


Date: October 30, 2002


                             /s/ Ruth Ann M. Gillis
                          ----------------------------
                               Ruth Ann M. Gillis
                Senior Vice President and Chief Financial Officer