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AS FILED WITH THE SECURITIES AND EXCHANGE COMMISSION ON SEPTEMBER 18, 2002

Registration No. 333-            

SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549

FORM S-4
REGISTRATION STATEMENT UNDER
THE SECURITIES ACT OF 1933

COMMONWEALTH EDISON COMPANY
(Exact Name of Registrant as Specified in its Charter)

Illinois
(State or Other Jurisdiction of Incorporation or Organization)

4911
(Primary Standard Industrial Classification Code Number)

36-0938600
(I.R.S. Employer Identification No.)

37th Floor
10 South Dearborn Street
Post Office Box 805379
Chicago, Illinois 60680-5379
(312) 394-4321
(Address and telephone number of Registrant's principal executive offices)

Robert E. Berdelle, Vice President, Finance and Chief Financial Officer
37th Floor
10 South Dearborn Street
Post Office Box 805379
Chicago, Illinois 60680-5379
(312) 394-3117
(Name, address and telephone number of agent for service)

Copies to:

Richard W. Astle, Esq.
Sidley Austin Brown & Wood
Bank One Plaza
10 South Dearborn Street
Chicago, Illinois 60603 		  Carter C. Culver, Esq.
Associate General Counsel—Corporate & Commercial
Exelon Business Services Company
10 South Dearborn Street, 35 th Floor
Chicago, Illinois 60603

        Approximate date of commencement of proposed sale to the public: As soon as practicable after the effective date of this Registration Statement.

        If the securities being registered on this form are being offered in connection with the formation of a holding company and there is a compliance with General Instruction G, check the following box.  o

        If this form is filed to register additional securities for an offering under Rule 462(b) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.  o

        If this form is a post-effective amendment filed under the Rule 462(d) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.  o

Calculation of Registration Fee


Title of Each Class of Securities to Be Registered   Amount to be Registered   Proposed Maximum Offering Price Per Unit   Proposed Maximum Aggregate Offering Price   Amount of Registration Fee(1)
First Mortgage 6.15% Bonds, Series 98 Due March 15, 2012   $600,000,000   100%   $600,000,000   $55,200
(1)
Calculated in compliance with Rule 457(f) under the Securities Act of 1933.

         The Registrant hereby amends this registration statement on such date or dates as may be necessary to delay its effective date until the Registrant shall file a further amendment which specifically states that this registration statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933 or until this registration statement shall become effective on the date as the Commission, acting pursuant to Section 8(a), may determine.

Subject to Completion, Dated September 18, 2002

The information in this prospectus is not complete and may be changed. We may not consummate the exchange offer until the registration statement filed with the Securities and Exchange Commission is effective. This prospectus is not an offer to sell the exchange bonds and it is not soliciting an offer to buy these exchange bonds in any state where the offer or sale is not permitted.

PROSPECTUS

COMED LOGO

$600,000,000
Commonwealth Edison Company
Exchange Offer for $600,000,000 First Mortgage 6.15% Bonds, Series 98 Due March 15, 2012


        See "Risk Factors" beginning on page 7 for a discussion of several matters that should be considered by holders before tendering their outstanding bonds in the exchange offer.

        We refer to the outstanding bonds and the exchange bonds together as the bonds (unless the context requires otherwise).

        There has not previously been any public market for the exchange bonds that will be issued in the exchange offer. We do not intend to list the exchange bonds on any national stock exchange or on the Nasdaq National Market. There can be no assurance that an active market for such exchange bonds will develop.

         Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved the bonds to be issued in the exchange offer or determined that this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

        [    ], 2002

        You should rely only on the information contained in this prospectus and the other information incorporated herein by reference. We have not authorized anyone to provide you with different information. We are not making an offer of these exchange bonds in any state where the offer is not permitted. You should not assume that the information contained in this prospectus or incorporated by reference herein is accurate as of any date other than the date on the front cover of this prospectus or the date of the documents incorporated by reference herein. Our business, financial condition, results of operations and prospects may have changed since that date.


TABLE OF CONTENTS

 
  Page
PROSPECTUS SUMMARY   3
RISK FACTORS   7
SUMMARY FINANCIAL INFORMATION   9
USE OF PROCEEDS   14
THE EXCHANGE OFFER   14
DESCRIPTION OF EXCHANGE BONDS   23
SUMMARY OF UNITED STATES FEDERAL INCOME TAX CONSIDERATIONS   32
PLAN OF DISTRIBUTION   33
LEGAL MATTERS   34
EXPERTS   34
WHERE YOU CAN FIND MORE INFORMATION   35
INCORPORATION OF CERTAIN DOCUMENTS BY REFERENCE   35

        This exchange offer is not being made to, nor will we accept surrenders for exchange from, holders of outstanding bonds in any jurisdiction in which the exchange offer or the acceptance thereof would not be in compliance with the securities or blue sky laws of that jurisdiction.

        Each broker-dealer that receives exchange bonds for its own account pursuant to the exchange offer must acknowledge that it will deliver a prospectus in connection with any resale of those exchange bonds. The letter of transmittal accompanying this prospectus states that by so acknowledging and by delivering a prospectus, a broker-dealer will not be deemed to admit that it is an "underwriter" within the meaning of the Securities Act of 1933. This prospectus, as it may be amended or supplemented from time to time, may be used by a broker-dealer in connection with resales of exchange bonds received in exchange for outstanding bonds where those outstanding bonds were acquired by that broker-dealer as a result of market-making activities or other trading activities. The company has agreed that, starting on the expiration date of the exchange offer and ending on the close of business one year after the expiration date, it will make this prospectus available to any broker-dealer for use in connection with any such resale. See "Plan of Distribution".

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PROSPECTUS SUMMARY

        You should carefully read the information set forth below and the information incorporated by reference herein as set forth under "Incorporation of Certain Documents by Reference" for information with respect to us. Unless the context requires otherwise, the terms "ComEd," "Company," "we," "our," "ours" and "us" refer to Commonwealth Edison Company and its subsidiaries. However, in the section captioned "Description of Exchange Bonds" and related matters, these terms refer solely to Commonwealth Edison Company and not to any of Commonwealth Edison Company's subsidiaries.

Commonwealth Edison Company

        Commonwealth Edison Company is a subsidiary of Exelon Corporation and is engaged principally in the purchase, transmission, distribution and sale of electricity to a diverse base of residential, commercial, industrial and wholesale customers in northern Illinois. ComEd's traditional retail service territory covers approximately 11,300 square miles and an estimated population of approximately 8 million as of December 31, 2001. The service territory includes the City of Chicago, an area of about 225 square miles with an estimated population of approximately 3 million. ComEd delivered electricity to approximately 3.6 million customers as of December 31, 2001.

        During January, 2001, Exelon undertook a corporate restructuring to separate its non-regulated generation and other competitive businesses from its regulated energy delivery businesses. As part of the corporate restructuring, effective January 1, 2001, ComEd's assets and liabilities unrelated to energy delivery were transferred to separate subsidiaries of Exelon. The transferred assets and liabilities are related to nuclear generation and wholesale energy services and administrative functions for other business activities of Exelon and its subsidiaries. In connection with the restructuring, ComEd entered into a power purchase agreement with Exelon Generation Company, LLC, a wholly owned subsidiary of Exelon, to supply ComEd with all of its electric load requirements for customers through 2004. As a result of the restructuring, our transmission and distribution assets are the principal properties subject to the lien of our Mortgage that secures the bonds.

        As a public utility under the Illinois Public Utilities Act, ComEd is subject to regulation by the Illinois Commerce Commission, including regulation as to rates and charges, issuance of most of its securities, services and facilities, classification of accounts, transactions with affiliated interests, as defined in the Illinois Public Utilities Act, and other matters. As a subsidiary of Exelon, a registered holding company under the Public Utility Holding Company Act of 1935, ComEd is subject to a number of restrictions under that Act. As an electric utility under the Federal Power Act, ComEd is also subject to regulation by the Federal Energy Regulatory Commission ("FERC") as to transmission rates and certain other aspects of its business, including interconnections and sales of transmission related assets.

        ComEd's principal executive offices are located at 10 South Dearborn Street, Chicago, Illinois 60603 and its telephone number is (312) 394-4321.

Exelon Corporation

        Exelon Corporation became the parent corporation for each of ComEd and PECO Energy Company ("PECO") as a result of the completion on October 20, 2000 of the transactions contemplated by an Agreement and Plan of Exchange and Merger, as amended, among PECO, Unicom Corporation and Exelon. Unicom was the former parent corporation of ComEd. Exelon, through its subsidiaries, operates in three business segments:

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        Exelon's principal executive offices are located at 10 South Dearborn Street, Chicago, Illinois 60603 and its telephone number is (312) 394-4321.

The Exchange Offer

        For a more complete description of the terms of the exchange offer, see "Exchange Offer" below in this prospectus.

Registration Rights   You are entitled to exchange your outstanding bonds for freely tradable exchange bonds with substantially identical terms to the outstanding bonds. The exchange offer is intended to satisfy your registration rights. After the exchange offer is complete, you will no longer be entitled to any exchange or registration rights with respect to your outstanding bonds. Accordingly, if you do not exchange your outstanding bonds, you will not be able to reoffer, resell or otherwise dispose of your outstanding bonds, unless you comply with the registration and prospectus delivery requirements of the Securities Act, or there is an exemption available.

The Exchange Offer
 
We are offering to exchange $1,000 principal amount of our First Mortgage 6.15% Bonds, Series 98 due March 15, 2012, which have been registered under the Securities Act, for $1,000 principal amount of our outstanding First Mortgage 6.15% Bonds, Series 98 due March 15, 2012, which were issued in private offerings on March 13, 2002 and June 20, 2002. As of the date of this prospectus, there are $600 million principal amount of outstanding bonds. We will issue exchange bonds promptly after the expiration of the exchange offer.

Resales
 
We believe that the exchange bonds issued in the exchange offer may be offered for resale, resold or otherwise transferred by you without compliance with the registration and prospectus delivery requirements of the Securities Act, provided that:

 
 
•
 
you are acquiring the exchange bonds in the ordinary course of your business;

 
 
•
 
you are not participating, do not intend to participate and have no arrangement or understanding with any person to participate in a distribution of the exchange bonds; and

 
 
•
 
you are not an "affiliate" of ours.

 
 
If you do not meet the above criteria, you will have to comply with the registration and prospectus delivery requirements of the Securities Act in connection with any reoffer, resale or other disposition of your exchange bonds.

 
 
 
 
 

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Each broker or dealer that receives exchange bonds for its own account in exchange for outstanding bonds that were acquired as a result of market-making or other trading activities must acknowledge that it will deliver this prospectus in connection with any sale of exchange bonds.

Expiration Date
 
5:00 p.m., New York City time, on                        , 2002, unless we extend the expiration date.

Conditions to the
Exchange Offer
 
The exchange offer is subject to several customary conditions, which may be waived by us. The exchange offer is not conditioned upon any minimum principal amount of outstanding bonds being tendered.

Procedures for
Tendering Outstanding
Bonds
 
If you wish to tender outstanding bonds, you must complete, sign and date the letter of transmittal, or a facsimile of it, in accordance with our instructions and transmit the letter of transmittal, together with your outstanding bonds to be exchanged and any other required documentation, to the exchange agent (see "Exchange Agent" below), at its address set forth in the letter of transmittal to arrive by 5:00 p.m., New York City time, on the expiration date. By executing the letter of transmittal, you will represent to us that you are acquiring the exchange bonds in the ordinary course of your business, that you are not participating, do not intend to participate and have no arrangement or understanding with any person to participate in the distribution of exchange bonds and that you are not an "affiliate" of ours. See "The Exchange Offer—Procedures for Tendering Outstanding Bonds."

Special Procedures for
Beneficial Holders
 
If you are the beneficial holder of outstanding bonds that are registered in the name of your broker, dealer, commercial bank, trust company or other nominee, and you wish to tender in the exchange offer, you should contact the person in whose name your outstanding bonds are registered promptly and instruct such person to tender on your behalf. See "The Exchange Offer—Procedures for Tendering Outstanding Bonds."

Guaranteed Delivery
Procedures
 
If you wish to tender your outstanding bonds and you cannot deliver such outstanding bonds, the letter of transmittal or any other required documents to the exchange agent before the expiration date, you may tender your outstanding bonds according to the guaranteed delivery procedures set forth in "The Exchange Offer—Guaranteed Delivery Procedures."

Withdrawal Rights
 
Tenders may be withdrawn at any time before 5:00 p.m., New York City time, on the expiration date.

Acceptance of
Outstanding Bonds and
Delivery of Exchange
Bonds
 
Subject to certain conditions, we will accept for exchange any and all outstanding bonds which are properly tendered in the exchange offer before 5:00 p.m., New York City time, on the expiration date. The exchange bonds will be delivered promptly after the expiration date. See "The Exchange Offer—Terms of the Exchange Offer."

Summary of Federal
Income Tax
Considerations
 
The exchange of outstanding bonds for exchange bonds will not be a taxable event for United States federal income tax purposes. You will not recognize any taxable gain or loss as a result of exchanging outstanding bonds for exchange bonds and you will have the same tax basis and holding period in the exchange bonds as you had in the outstanding bonds immediately before the exchange. See "Summary of the United States Federal Income Tax Considerations."

 
 
 
 
 

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Use of Proceeds
 
We will not receive any proceeds from the issuance of the exchange bonds.

Exchange Agent
 
BNY Midwest Trust Company is serving as exchange agent in connection with the exchange bonds. The address, telephone number and facsimile number of the exchange agent is set forth in "The Exchange Offer—Exchange Agent."

The Exchange Bonds

        For a more complete description of the terms of the exchange bonds, see "Description of Exchange Bonds" below in this prospectus

Issuer   Commonwealth Edison Company
Bonds Offered   $600,000,000 First Mortgage 6.15% Bonds, Series 98 due March 15, 2012.
Maturity Date   March 15, 2012.
Interest Payment Dates   March 15 and September 15, beginning on September 15, 2002.
Ranking   The outstanding bonds were, and the exchange bonds will be, our secured obligations, equal in right of payment to all other bonds currently outstanding or hereafter issued under our Mortgage. The Mortgage under which the outstanding bonds were, and the exchange bonds will be, issued prohibits us from incurring other debt senior or equal to the bonds (unless certain tests are met).
Optional Redemption   We may redeem all or a part of the bonds at any time and from time to time by paying a "make-whole" premium based on U.S. Treasury rates as described under "Description of Exchange Bonds—Redemption at Our Option."
Risk Factors   You should consider carefully all of the information set forth in this prospectus and, in particular, you should evaluate the specific factors set forth under "Risk Factors" herein and the information contained in our 2001 Form 10-K before deciding whether to invest in the exchange bonds.

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RISK FACTORS

        In addition to the information contained elsewhere in this prospectus and in the documents incorporated by reference herein, the following risk factors should be carefully considered by each prospective investor in deciding to exchange your outstanding bonds for exchange bonds.

Risks Relating to the Exchange Bonds

        The agreements governing our indebtedness contain various covenants that limit our management's discretion in the operation of our businesses and also require us to meet certain financial maintenance tests. Failure to comply with any of these tests could have a material adverse effect on us.

        The agreements governing our indebtedness contain various covenants, including those that restrict our ability to:

Any failure to comply with the restrictions of any of our existing or new credit facilities or any agreement governing our indebtedness, including the Mortgage, may result in a default under such facilities and agreements. Such default may allow the creditors to accelerate the related debt, which acceleration may trigger cross-acceleration or cross-default provisions in other debt. For more information, see "Description of Exchange Bonds."

There is no public market for the exchange bonds.

        Following the completion of this exchange offer, the exchange bonds will be freely tradable by most holders. See "The Exchange Offer." We do not intend to list the exchange bonds on any United States or foreign securities exchange. We can give no assurances concerning the liquidity of any market that may develop for the exchange bonds, the ability of any investor to sell the exchange bonds, or the price at which investors would be able to sell their exchange bonds. If a market for the exchange bonds does not develop, investors may be unable to resell the exchange bonds for an extended period of time, if at all. Consequently, investors may not be able to liquidate their investment readily, and lenders may not readily accept the exchange bonds as collateral for loans.

        It is possible that the market for the outstanding bonds, as well as for the publicly tradable exchange bonds for which they may be exchanged, will be volatile. This volatility may affect your ability to resell your outstanding bonds or the exchange bonds as well as the timing of any such resale or exchange.

Failure to exchange your outstanding bonds will leave them subject to transfer restrictions.

        Any outstanding bonds that remain outstanding after this exchange offer will continue to be subject to restrictions on their transfer. After this exchange offer, holders of outstanding bonds will not have any further rights under the registration rights agreement, with limited exceptions. In general, outstanding bonds may not be offered or sold unless registered under the Securities Act, except pursuant to an exemption from, or in a transaction not subject to, the Securities Act and applicable state securities laws. We currently do not anticipate registering the outstanding bonds under the Securities Act. As outstanding bonds are tendered and accepted in the exchange offer, the aggregate principal amount of outstanding bonds will decrease, which decrease will decrease their liquidity. Any market for outstanding bonds that are not exchanged could be adversely affected by the conclusion of this exchange offer.

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Late deliveries of the outstanding bonds and other required documents could prevent a holder from exchanging its bonds.

        Holders are responsible for complying with all exchange offer procedures. Issuance of exchange bonds in exchange for outstanding bonds will only occur upon completion of the procedures described in this prospectus under the heading "The Exchange Offer—Procedures for Tendering Outstanding Bonds." Therefore, holders of outstanding bonds who wish to exchange them for exchange bonds should allow sufficient time for completion of the exchange procedure. We are not obligated to notify you of any failure to follow the proper procedure.

If you are a broker-dealer, your ability to transfer the bonds may be restricted.

        A broker-dealer that purchased outstanding bonds for its own account as part of market-making or trading activities must deliver a prospectus when it sells the exchange bonds. Our obligation to make this prospectus available to broker-dealers is limited. Consequently, we cannot guarantee that a proper prospectus will be available to broker-dealers wishing to resell their exchange bonds.

Risks Relating to Accounting

        You may have no effective remedy against Arthur Andersen LLP or any of our directors, officers or underwriters in connection with a material misstatement in some of our audited financial statements incorporated by reference in this prospectus.

        Arthur Andersen LLP, the independent public accountants that audited our financial statements incorporated by reference in this prospectus for the year ended December 31, 1999, was convicted on June 15, 2002 on federal obstruction of justice charges arising from the government's investigation of Enron Corp.

        Arthur Andersen LLP did not participate in the preparation of this prospectus or the related registration statement. As a result, we have not been able to obtain, after reasonable efforts, the written consent of Arthur Andersen LLP to include in this prospectus its reports which are incorporated by reference in this prospectus. As permitted under recent Securities Act rule changes, we have not filed the written consent of Arthur Andersen LLP that would otherwise be required by the Securities Act. As a result, your claims against Arthur Andersen LLP under the Securities Act based on these financial statements may be limited. Moreover, even if claims against Arthur Andersen LLP are permitted, Arthur Andersen LLP may not have the financial resources to satisfy any judgment. In addition, notwithstanding that we have not filed the written consent of Arthur Andersen LLP, our directors, officers and underwriters may still be able to establish a due diligence defense to any claim relating to those financial statements on the basis they were made on the authority of an expert, which could limit your ability to assert a claim against them.

8



SUMMARY FINANCIAL INFORMATION

        We have provided the following summary financial information for your reference. We have derived the summary information presented here from the financial statements we have incorporated by reference into this prospectus. You should read it together with our historical consolidated financial statements and the related notes incorporated by reference in this prospectus. See "Where You Can Find More Information" below.

        Our financial statements for the year ended December 31, 2001 and for the periods from January 1, 2000 to October 19, 2000 and October 20, 2000 to December 31, 2000 were audited by PricewaterhouseCoopers LLP. Our consolidated financial statements for the year ended December 31, 1999 were audited by Arthur Andersen LLP. Arthur Andersen LLP has not consented to our incorporation by reference of their reports contained in the filings we have incorporated by reference in this prospectus. See "Experts" below for more information.

        The merger transaction in which we became a subsidiary of Exelon was accounted for using the purchase method of accounting in accordance with generally accepted accounting principles. The effects of the purchase method are reflected in our financial statements as of the merger date, October 20, 2000. Accordingly, our financial information presented for the period after the merger reflects a new basis of accounting. Financial information for 2000, separated by a black line, is presented for periods prior to and subsequent to the merger.

        In addition, effective January 1, 2001, our assets and liabilities unrelated to energy delivery were transferred to separate subsidiaries of Exelon as part of Exelon's restructuring. Thus, beginning in January 2001, our operations consist of our retail electricity distribution and transmission business in northern Illinois. The restructuring has had a significant impact on our assets, liabilities and equity and our results of operations. Our results of operations and assets and liabilities prior to January 2001 do not reflect the restructuring.

 
   
   
   
   
  Six Months Ended June 30,
 
 
  Year Ended
December
31,
1999
   
   
  Year Ended
December
31,
2001
 
 
  Jan 1-
Oct. 19,
2000
  Oct. 20-
Dec. 31,
2000
 
 
  2001
  2002
 
 
  ($ in millions)

 
Income Statement Data                                      
  Operating revenues   $ 6,793   $ 5,702   $ 1,310   $ 6,206   $ 2,976   $ 2,796  
  Operating income     1,549     1,048     338     1,594     840     834  
  Net income on common stock     599     596     133     607     329     360  
  Adjusted net income(a)     599     596     156     733     393     360  

Cash Flow Data
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  EBITDA(b)   $ 2,451   $ 2,060   $ 512   $ 2,259   $ 1,174   $ 1,102  
  Cash interest paid(c)     588     418     88     451     247     217  
  Investment in plant     1,337     1,210     196     839     451     357  
  Cash flows from operations     1,243     1,074     524     1,352     705     740  
  Cash flows (used in) provided by investing activities     1,146     (827 )   (800 )   (441 )   (58 )   (352 )
  Cash flows used in financing activities     (1,161 )   (956 )   (129 )   (1,029 )   (322 )   (57 )

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  As of December 31,
   
 
  As of June 30,
2002
 
  1999
  2000
  2001
 
  ($ in millions)

Balance Sheet Data                        
Property, plant and equipment, net.   $ 11,993   $ 7,657   $ 7,351   $ 7,522
Total assets     22,576     20,198     15,716     16,198
Long-term debt(d).     6,962     6,882     5,850     6,095
Preferred securities     9     7     7     7
Common shareholders' equity     5,303     6,176     5,076     5,253
(a)
We adopted Statement of Accounting Standard (SFAS) No. 142, "Goodwill and Other Intangible Assets," as of January 1, 2002. SFAS No. 142 establishes new accounting and reporting standards for goodwill and intangible assets. We do not have significant other intangible assets recorded on our balance sheet. Under SFAS No. 142, goodwill is no longer subject to amortization; however, goodwill is subject to an assessment for impairment using a two-step fair value based test. We have performed both steps and have determined that there is no impairment of our goodwill

The following table sets forth our net income, adjusted to exclude amortization expense related to goodwill that is no longer being amortized.

 
   
   
   
   
  Six Months Ended
June 30,
 
  Year Ended
December 31,
1999
  Jan 1-
Oct. 19,
2000
  Oct. 20-
Dec. 31,
2000
  Year Ended
December 31,
2001
 
  2001
  2002
 
  ($ in millions)

Reported net income   $ 599   $ 596   $ 133   $ 607   $ 329   $ 360
Goodwill amortization     —     —     23     126     64     —
Adjusted net income   $ 599   $ 596   $ 156   $ 733   $ 393   $ 360
(b)
EBITDA is defined as operating income plus depreciation and amortization as reported in the consolidated statements of cash flows. EBITDA is not a measure of performance under generally accepted accounting principles, or GAAP. While EBITDA should not be considered as a substitute for net income, cash flows from operating activities and other income or cash flow statement data prepared in accordance with GAAP, or as a measure of profitability or liquidity, management understands that EBITDA is customarily used as a measure in evaluating companies.

(c)
Includes cash interest paid of $186 million, $162 million, $143 million, $74 million and $65 million in connection with the ComEd Transitional Funding Trust notes for the years ended December 31, 1999, 2000 and 2001 and for the six months ended June 30, 2001 and 2002, respectively.

(d)
Excludes current maturities of $732 million, $348 million, $849 million and $848 million as of December 31, 1999, 2000 and 2001, and June 30, 2002, respectively.

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Ratio of Earnings to Fixed Charges

 
  12 Months Ended
December 31,
   
   
   
  Six Months
Ended June 30,
 
  Jan. 1-
Oct. 19,
2000
  Oct. 20-
Dec. 31,
2000
  12 Months
Ended Dec. 31,
2001
 
  1997
  1998
  1999
  2001
  2002
Earnings to Fixed Charges(d)   (e ) 2.59   2.45   2.62   2.69   2.89   2.99   3.20
(d)
For purposes of computing the ratios of earnings to fixed charges: (i) earnings consist of net income before deducting net provisions for income taxes (including deferred taxes and current income taxes applicable to nonoperating activities), investment tax credits deferred and fixed charges; and (ii) fixed charges consist of interest on debt, amortization of debt discount, premium and expense, and the estimated interest component of nuclear fuel and other lease payments and rentals.

(e)
Our earnings for 1997 were inadequate to cover fixed charges by approximately $259 million. This inadequacy was principally caused by charges related to the closure of our Zion Nuclear Generating Station and our discontinuation of regulatory accounting practices for the generation portion of our business and other charges recorded as a result of the electric utility restructuring legislation adopted in Illinois in 1997.

Notes to Summary Financial Information

        Under electric utility restructuring legislation known as the Electric Service Customer Choice and Rate Relief Law of 1997, or the Restructuring Legislation, adopted in Illinois, all of our customers have the choice to purchase energy from other suppliers and non-residential customers can also elect a power purchase option. The power purchase option allows the purchase of electric energy from us at market-based prices. On May 1, 2002, all of our residential customers became eligible to choose their supplier of electricity. However, as of June 30, 2002, no alternative electric supplier had sought approval from the ICC to serve residential customers, nor has any electric utility chosen to enter our residential market for the supply of electricity. As of June 30, 2002, approximately 22,600 retail customers, representing approximately 25% of our retail kilowatt-hour sales for the six months ended June 30, 2002, had elected to receive their electric energy from an alternative electric supplier or chose the power purchase option.

        On April 1, 2002, the ICC issued an interim order in our Delivery Services Rate Case. The interim order is subject to an audit of test year expenditures that is anticipated to be completed by the end of 2002, with a final order to be issued in 2003. The purpose of the audit is to analyze and establish the reasonableness of past investments and expenditures, which we believe we have shown and will be shown in the audit. The order sets delivery rates for residential customers choosing a retail electric supplier. The rates became effective on May 1, 2002 when residential customers became eligible to choose their electricity supplier. Traditional bundled rates—rates paid by customers that retain us as their electricity supplier—are not affected by this order. As a result of amendments made on June 6, 2002 to the Restructuring Legislation, bundled rates will remain frozen through 2006. Delivery service rates for non-residential customers are not affected by this order. The potential revenue impact of the interim order is not expected to be material in 2002.

        In addition to retail competition for generation services, the Restructuring Legislation also provided a 15% residential base rate reduction effective August 1, 1998 and an additional 5% residential base rate reduction in October 2001. Our operating revenues were reduced by approximately $78 million for the six months ended June 30, 2002 and $24 million in 2001 due to the 5% residential base rate reduction. Notwithstanding the rate reductions and subject to certain earnings tests, a rate

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freeze will generally be in effect until January 1, 2007. The rate freeze period was extended to January 1, 2007 as a result of amendatory legislation enacted on June 6, 2002. A utility may request a base rate increase during the rate freeze period only when necessary to ensure the utility's financial viability.

        On July 19, 2002, we filed a request with the ICC to revise the provider of last resort obligation we have in Illinois to be the back-up energy supplier to certain businesses. We are seeking permission from the ICC to limit availability by June 2006 of Rate 6L for 370 of our largest energy customers with energy demands of at least three megawatts, totaling approximately 2,500 megawatts. Rate 6L is a bundled fixed rate offered to large customers including heavy industrial plants, large office buildings, government facilities and a variety of other businesses. The ICC has 120 days from the date of the filing to act on our request or it will be deemed approved.

        Under the Restructuring Legislation, if the earned return on common equity of a utility during the rate freeze period exceeds an established threshold, one-half of the excess earnings must be refunded to customers. The threshold rate of return on common equity is currently based on the 30-year Treasury Bond rate plus 8.5% in the years 2000 through 2006; although the Monthly Treasury Long-Term Average (25 years and above) will be used when the 30-year Treasury Bond rate is no longer included in the Federal Reserve System's H.15 Statistical Release. Earnings for purposes of our threshold include our net income calculated in accordance with GAAP and reflect the amortization of regulatory assets and goodwill. At December 31, 2001, we had a regulatory asset with an unamortized balance of $277 million that we expect to fully recover and amortize through the transition period. Consistent with the provisions of the Restructuring Legislation, regulatory assets may be recovered at amounts which provide us an earned return on common equity within the threshold. The utility's earned return on common equity and our threshold return on common equity are each calculated on a two-year average basis. We did not trigger the earnings sharing provision in 2000. Subject to the satisfactory resolution of the matter discussed in the next paragraph, we did not trigger the earnings sharing provision in 2001 and do not currently expect to trigger that provision in the years 2002 through 2006.

        On August 27, 2002, we received a letter order from the Staff of the Federal Energy Regulatory Commission directing us to remove from our FERC-required books the amount of goodwill associated with the generating assets and power marketing business that we transferred in January 2001 as part of an Exelon corporate restructuring to separate generation assets from transmission and distribution assets. At the time of the transfer, we had on our books approximately $4.8 billion of goodwill that was recognized in connection with the October 2000 merger transaction that resulted in the formation of Exelon. The letter order was in response to a request that we made in July 2001 for approval by FERC of our accounting entries related to that corporate restructuring. We filed a petition with FERC requesting a stay and rehearing on the matter. If the FERC letter order stands and it is ultimately determined that a significant portion of our recorded goodwill is attributable to the transferred assets, then we could be required to amend our financial statements filed with FERC accordingly. Although we believe that none of the $4.8 billion of goodwill relates to the transferred generation or power marketing assets, the FERC letter order does not indicate how much goodwill FERC believes should be removed from our books, or how such an amount should be determined, and as a result we cannot estimate what the impact of such an amendment might be. Because the above-described earnings sharing provision is based on our FERC financial statements, an amendment to those financial statements could have a material adverse effect on our financial results, including refunds to our customers in respect of our earnings during 2001, and could affect our cost of capital.

        The Restructuring Legislation also provided for the collection of a competitive transition charge, or CTC, from customers who choose to purchase electric energy from an alternative supplier or elect the power purchase option during a transition period that extends through 2006. The CTC was established as of October 1, 1999 and is applied on a cents per kilowatt-hour basis. It considers the

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revenue that would have been collected from a customer under tariffed rates, reduced by the revenue the utility will receive for providing delivery services to the customer, the market price for electricity and a defined mitigation factor, which represents the utility's opportunity to develop new revenue sources and achieve cost savings. The CTC allows us to recover some of our costs that might otherwise be unrecoverable under market-based rates.

        As part of a settlement agreement between us and the City of Chicago relating to our Chicago franchise agreement, we agreed with the City of Chicago to a revised combination of ongoing work under the franchise agreement and new initiatives that total approximately $1 billion in defined transmission and distribution expenditures by us to improve electric service in Chicago. The Illinois legislation also committed us to spend at least $2 billion during the period 1999 through 2004 on transmission and distribution facilities outside of Chicago. We have substantially completed these expenditures inside and outside of Chicago. In addition, we conducted an extensive evaluation of the reliability of our transmission and distribution systems in response to several outages in the summer of 1999. As a result of the evaluation, we increased our capital and operating and maintenance expenditures on our transmission and distribution facilities in order to improve their reliability.

        As a result of our commitments to improve the reliability of our transmission and distribution system, we expect our capital expenditures will exceed depreciation on our rate base assets through at least 2003. The base rate freeze will generally preclude rate recovery of and on those investments prior to January 1, 2007 from customers who receive service from us under bundled rates. Unless we can offset the additional carrying costs against cost savings, our return on investment will be reduced during the period of the rate freeze and until rate increases are approved authorizing a return of and on this new investment.

        In addition, the Restructuring Legislation provides that an electric utility, such as us, will be liable for actual damages suffered by customers in the event of a continuous power outage of four hours or more affecting 30,000 or more customers and provides for reimbursement of governmental emergency and contingency expenses incurred in connection with any such outage. That legislation bars recovery of consequential damages. The Restructuring Legislation also allows an affected utility to seek relief from these provisions from the ICC where the utility can show that the cause of the outage was unpreventable damage due to weather events or conditions, customer tampering or third party causes.

        The Restructuring Legislation also allows a portion of our future revenues to be segregated and used to support the issuance of securities by ComEd or a special purpose financing subsidiary. The proceeds, net of transaction costs, from those securities issuances must be used to refinance outstanding debt or equity or for certain other limited purposes. The total amount of those securities that may be issued is approximately $6.8 billion. In December 1998, our special purpose financing subsidiaries issued $3.4 billion of notes.

        In December 1999, FERC issued Order No. 2000 requiring jurisdictional utilities, such as ComEd, to file a proposal to form a regional transmission organization, or RTO, meeting certain governance, operational, and scope and scale requirements articulated in the order or, alternatively, to describe efforts to participate in or work toward participating in an RTO or explain why they were not participating in an RTO. Order No. 2000 is generally designed to separate the governance and operation of the transmission system from generation companies and other market participants. PECO is already a member of PJM Interconnection, LLC, an existing independent system operator that is seeking to be approved as an RTO. We initially joined the Midwest Independent System Operator, but withdrew in order to help form the proposed Alliance RTO. FERC rejected the Alliance RTO proposal in December 2001 and directed the Alliance companies to reconsider their RTO development plans.

        On May 28, 2002, we filed a notice with FERC indicating our intention to join PJM. FERC conditionally approved our decision to join PJM in late July 2002. On August 30, 2002, we, along with several subsidiaries of American Electric Power Service Corporation (AEP), Dayton Power and Light

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Company and National Grid USA (Grid), filed a non-binding letter of intent and transaction term sheet with FERC regarding the proposed formation of an independent transmission company, or ITC, within PJM. Grid is a subsidiary of National Grid plc, a company which owns and operates transmission assets in Great Britain. Under the letter of intent, Grid will make specified capital contributions to the ITC and will, for an initial term of three years, be the ITC's managing member responsible for directing its business and affairs. Grid will receive an annual management fee for serving as managing member together with incentive compensation tied to the efficiency of operations and enhanced transmission operations. We, along with AEP and Dayton, will transfer operation of our respective transmission systems to the ITC and PJM. The ITC and PJM will allocate responsibilities between them consistent with FERC requirements. The transmission owners participating in the ITC will have the right to contribute transmission facilities to the ITC in exchange for passive ownership interests in the ITC. Grid, AEP, Dayton and we have rights to withdraw from or dissolve the ITC or to terminate Grid as managing member at the end of the initial three year term of the managing member or any renewal period.


USE OF PROCEEDS

        We will not receive any cash proceeds from the issuance of the exchange bonds offered by this prospectus. In consideration for issuing the exchange bonds as contemplated by this prospectus, we will receive a like principal amount of outstanding bonds. The terms of the exchange bonds will be identical in all material respects to the terms of the outstanding bonds for which they are exchanged, except that the transfer restrictions and registration rights applicable to the outstanding bonds will not be applicable to the exchange bonds. The outstanding bonds tendered in exchange for the exchange bonds will be retired and canceled. Accordingly, the issuance of the exchange bonds will not result in any increase in our indebtedness.


THE EXCHANGE OFFER

Purpose and Effect of the Exchange Offer

        Exchange Offer Registration Statement.     We issued the outstanding bonds in two separate offerings on March 13, 2002 and June 20, 2002. The initial purchasers have advised us that they subsequently resold the outstanding bonds to "qualified institutional buyers" in reliance on Rule 144A under the Securities Act. As a condition to the offerings of the outstanding bonds, we entered into registration rights agreements dated March 13, 2002 and June 20, 2002, pursuant to which we agreed, for the benefit of all holders of the outstanding bonds, at our own expense, to use our best efforts to consummate the exchange offer within 270 days after the initial issue date of the outstanding bonds.

        Further, we agreed to keep the exchange offer open for acceptance for not less than 20 nor more than 30 business days (or longer if required by applicable law). For each outstanding bond validly tendered pursuant to the exchange offer and not withdrawn, the holder of that bond will receive an exchange bond having a principal amount equal to that of the tendered outstanding bond. Interest on each exchange bond will accrue from the last date on which interest was paid on the tendered outstanding bond in exchange therefor or, if no interest was paid on that outstanding bond, from the issue date.

        The following is a summary of the registration rights agreements relating to the outstanding bonds. As a summary, it does not contain all of the information you might find useful. For further information, you should read the registration rights agreements, copies of which have been filed as exhibits to the registration statement. The exchange offer is intended to satisfy certain of our obligations under the registration rights agreements.

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        Transferability.     We issued the outstanding bonds on March 13, 2002 and June 20, 2002 in two separate transactions exempt from the registration requirements of the Securities Act and applicable state securities laws. Accordingly, the outstanding bonds may not be offered or sold in the United States unless registered or pursuant to an applicable exemption under the Securities Act and applicable state securities laws. Based on no-action letters issued by the staff of the Commission with respect to similar transactions, we believe that the exchange bonds issued pursuant to the exchange offer in exchange for outstanding bonds may be offered for resale, resold and otherwise transferred by holders of bonds who are not our affiliates without further compliance with the registration and prospectus delivery requirements of the Securities Act, provided that:

        However, we have not sought a no-action letter with respect to the exchange offer and we cannot assure you that the staff of the Commission would make a similar determination with respect to the exchange offer. Any holder who tenders its outstanding bonds in the exchange offer with any intention of participating in a distribution of exchange bonds (1) cannot rely on the interpretation by the staff of the Commission, (2) will not be able to validly tender outstanding bonds in the exchange offer and (3) must comply with the registration and prospectus delivery requirements of the Securities Act in connection with any secondary resale transactions.

        In addition, each broker-dealer that receives exchange bonds for its own account pursuant to the exchange offer must acknowledge that it will deliver a prospectus in connection with any resale of those exchange bonds. The letter of transmittal accompanying this prospectus states that by so acknowledging and by delivering a prospectus, a broker-dealer will not be deemed to admit that it is an "underwriter" within the meaning of the Securities Act. This prospectus, as it may be amended or supplemented from time to time, may be used by a broker-dealer in connection with resales of exchange bonds received in exchange for outstanding bonds where those outstanding bonds were acquired by that broker-dealer as a result of market-making activities or other trading activities. We have agreed that, starting on the expiration date of the exchange offer and ending on the close of business one year after the expiration date, we will make this prospectus available to any broker-dealer for use in connection with any such resale. See "Plan of Distribution."

        Each broker-dealer that receives exchange bonds for its own account in exchange for outstanding bonds, where those bonds were acquired by such broker dealer as a result of market-making activities or other trading activities, must acknowledge that it will deliver a prospectus in connection with any resale of those exchange bonds. See "Plan of Distribution."

        Shelf Registration Statement.     If applicable interpretations of the staff of the SEC do not permit us to effect the exchange offer or, for any other reason, this exchange offer is not consummated within 270 days after the date of original issue of the outstanding bonds, we will, at our cost:

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        We will, in the event a shelf registration statement is filed, among other things, provide to each holder for whom the shelf registration statement was filed copies of the prospectus that is a part of the shelf registration statement, notify each such holder when the shelf registration statement has become effective and take other actions as are required to permit unrestricted resales of the outstanding bonds or the exchange bonds, as the case may be. A holder selling outstanding bonds or exchange bonds pursuant to the shelf registration statement generally will be required to be named as a selling security holder in the related prospectus and to deliver a prospectus to purchasers, will be subject to applicable civil liability provisions under the Securities Act in connection with sales of that kind and will be bound by the provisions of the registration rights agreement that are applicable to that holder, including specified indemnification obligations. A holder will not be permitted to sell bonds pursuant to the shelf registration statement unless the holder has returned to us a completed and signed notice electing to be included and furnishing the holder's name and other information required to be included in the related prospectus. We will send the form of notice and questionnaire to holders at least 30 calendar days before the effectiveness of the shelf registration statement and holders will have 28 calendar days to return it.

        Special Interest.     If

additional interest will accrue on the principal amount of the outstanding bonds and the exchange bonds (in addition to the stated interest on the outstanding bonds and the exchange bonds) from and including the date on which the event referred to in clauses (a) and (b) shall occur to the date on which all such events have been cured or if earlier, the date on which the outstanding bonds and exchange bonds may first be resold in reliance on Rule 144(k). The additional interest will accrue at a rate of 0.50% per annum.

Terms of the Exchange Offer

        Upon satisfaction or waiver of all the conditions of the exchange offer, we will accept any and all outstanding bonds properly tendered and not withdrawn prior to the expiration date and will issue the exchange bonds promptly after acceptance of the outstanding bonds. See "—Conditions to the Exchange Offer" and "Procedures for Tendering Outstanding Bonds." We will issue $1,000 principal amount of exchange bonds in exchange for each $1,000 principal amount of outstanding bonds accepted in the exchange offer. As of the date of this prospectus, there are $600,000,000 aggregate principal amount of outstanding bonds. Holders may tender some or all of their outstanding bonds pursuant to the exchange offer. However, outstanding bonds may be tendered only in integral multiples of $1,000.

        The exchange bonds are identical to the outstanding bonds except for the elimination of certain transfer restrictions and registration rights pertaining to the outstanding bonds. The exchange bonds will evidence the same debt as the outstanding bonds and will be issued pursuant to, and entitled to the

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benefits of, the Mortgage pursuant to which the outstanding bonds were issued and will be deemed one issue of bonds, together with the outstanding bonds.

        This prospectus, together with the letter of transmittal, is being sent to all registered holders and to others believed to have beneficial interests in the outstanding bonds. Holders of outstanding bonds do not have any appraisal or dissenters' rights under the Mortgage in connection with the exchange offer. We intend to conduct the exchange offer in accordance with the applicable requirements of the Securities Act, the Exchange Act and the rules and regulations of the Commission promulgated thereunder.

        For purposes of the exchange offer, we will be deemed to have accepted validly tendered outstanding bonds when, and if, we have given oral or written notice thereof to the exchange agent. The exchange agent will act as our agent for the purpose of distributing the appropriate exchange bonds from us to the tendering holders. If we do not accept any tendered outstanding bonds because of an invalid tender, the occurrence of certain other events set forth in this prospectus or otherwise, we will return the unaccepted outstanding bonds, without expense, to the tendering holder thereof as promptly as practicable after the expiration date.

        Holders who tender outstanding bonds in the exchange offer will not be required to pay brokerage commissions or fees or, except as set forth below under "—Transfer Taxes," transfer taxes with respect to the exchange of outstanding bonds pursuant to the exchange offer. We will pay all charges and expenses, other than certain applicable taxes, in connection with the exchange offer. See "—Fees and Expenses."

Expiration Date; Extensions; Amendments

        The term "expiration date" shall mean 5:00 p.m., New York City time, on                        , 2002, for the exchange offer unless we, in our sole discretion, extend the exchange offer, in which case the term "expiration date" shall mean the latest date and time to which the exchange offer is extended. In order to extend the exchange offer, we will notify the exchange agent by oral or written notice and each appropriate registered holder by means of press release or other public announcement of any extension, in each case, prior to 9:00 a.m., New York City time, on the next business day after the previously scheduled expiration date. We reserve the right, in our sole discretion,

We will notify the exchange agent of any delay, extension, termination or amendment by oral or written notice. We will also notify each registered holder of any amendment. We will give to the exchange agent written confirmation of any oral notice.

Exchange Date

        As soon as practicable after the close of the exchange offer, we will accept for exchange all outstanding bonds properly tendered and not validly withdrawn prior to 5:00 p.m., New York City time, on the expiration date in accordance with the terms of this prospectus and the letter of transmittal.

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Conditions to the Exchange Offer

        Notwithstanding any other provisions of the exchange offer, and subject to our obligations under the registration rights agreement, we

if, at any time before the acceptance of outstanding bonds for exchange, any of the following events shall occur:

The foregoing conditions are for our sole benefit and may be asserted by us regardless of the circumstances giving rise to any such condition or may be waived by us in whole or in part at any time and from time to time in our sole discretion. Our failure at any time to exercise any of the foregoing rights shall not be deemed a waiver of any such right, and such right shall be deemed an ongoing right which may be asserted at any time and from time to time.

        In addition, we will not accept for exchange any outstanding bonds tendered, and no exchange bonds will be issued in exchange for any such outstanding bonds, if at such time any stop order shall be threatened by the Commission or be in effect with respect to the registration statement of which this prospectus is a part or the qualification of the Mortgage for the bonds under the Trust Indenture Act of 1939, as amended.

        The exchange offer is not conditioned on any minimum aggregate principal amount of outstanding bonds being tendered for exchange.

Consequences of Failure to Exchange

        Any outstanding bonds not tendered pursuant to the exchange offer will remain outstanding and continue to accrue interest. The outstanding bonds will remain "restricted securities" within the meaning of the Securities Act. Accordingly, prior to the date that is one year after the later of the issue date and the last date on which we or any of our affiliates was the owner of the outstanding bonds, the outstanding bonds may be resold only:

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subject, in each of the foregoing cases, to compliance with applicable state securities laws. As a result, the liquidity of the market for non-tendered outstanding bonds could be adversely affected upon completion of the exchange offer.

Fees and Expenses

        We will not make any payments to brokers, dealers or others soliciting acceptances of the exchange offer. The principal solicitation is being made by mail; however, additional solicitations may be made in person or by telephone by our officers and employees.

        Expenses incurred in connection with the exchange offer will be paid by us. Such expenses include, among others, the fees and expenses of the trustee and the exchange agent, accounting and legal fees, printing costs and other miscellaneous fees and expenses.

Accounting Treatment

        We will not recognize any gain or loss for accounting purposes upon the consummation of the exchange offer. We will amortize the expenses of the exchange offer as additional interest expense over the term of the exchange bonds.

Procedures for Tendering Outstanding Bonds

        The tender of outstanding bonds pursuant to any of the procedures set forth in this prospectus and in the letter of transmittal will constitute a binding agreement between the tendering holder and us in accordance with the terms and subject to the conditions set forth in this prospectus and in the letter of transmittal. The tender of outstanding bonds will constitute an agreement to deliver good and marketable title to all tendered outstanding bonds prior to the expiration date free and clear of all liens, charges, claims, encumbrances, interests and restrictions of any kind.

        Except as provided in "—Guaranteed Delivery Procedures," unless the outstanding bonds being tendered are deposited by you with the exchange agent prior to the expiration date and are accompanied by a properly completed and duly executed letter of transmittal, we may, at our option, reject the tender. Issuance of exchange bonds will be made only against deposit of tendered outstanding bonds and delivery of all other required documents. Notwithstanding the foregoing, DTC participants tendering through its Automated Tender Offer Program, or "ATOP," will be deemed to have made valid delivery where the exchange agent receives an agent's message, as defined below, prior to the expiration date.

        Accordingly, to properly tender outstanding bonds, the following procedures must be followed:

        Bonds held through a Custodian.     Each beneficial owner holding outstanding bonds through a DTC participant must instruct the DTC participant to cause its outstanding bonds to be tendered in accordance with the procedures set forth in this prospectus.

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        Bonds held through DTC.     Pursuant to an authorization given by DTC to the DTC participants, each DTC participant holding outstanding bonds through DTC must

        Promptly after the date of this prospectus, the exchange agent will establish an account at DTC for purposes of the exchange offer with respect to outstanding bonds held through DTC. Any financial institution that is a DTC participant may make book-entry delivery of interests in outstanding bonds into the exchange agent's account through ATOP. However, although delivery of interests in the outstanding bonds may be effected through book-entry transfer into the exchange agent's account through ATOP, an agent's message in connection with such book-entry transfer, and any other required documents, must be, in any case, transmitted to and received by the exchange agent at its address set forth under "—Exchange Agent," or the guaranteed delivery procedures set forth below must be complied with, in each case, prior to the expiration date. Delivery of documents to DTC does not constitute delivery to the exchange agent. The confirmation of a book-entry transfer into the exchange agent's account at DTC as described above is referred to herein as a "Book-Entry Confirmation."

        The term "agent's message" means a message transmitted by DTC to, and received by, the exchange agent and forming a part of the book-entry confirmation, which states that DTC has received an express acknowledgment from each DTC participant tendering through ATOP that such DTC participant has received a letter of transmittal and agrees to be bound by the terms of the letter of transmittal and that we may enforce such agreement against such DTC participants.

        Cede & Co., as the holder of the global bond, will tender a portion of the global bond equal to the aggregate principal amount due at the stated maturity for which instructions to tender are given by DTC participants.

        By tendering, each holder and each DTC participant will represent to us that, among other things:

        Unless waived by us, we will not accept any alternative, conditional, irregular or contingent tenders. By transmitting an acceptance through ATOP, each tendering holder waives any right to receive any notice of the acceptance for purchase of its outstanding bonds.

        We will resolve all questions as to the validity, form, eligibility (including time of receipt) and acceptance of tendered outstanding bonds, and that determination will be final and binding. We reserve the absolute right to reject any or all tenders that are not in proper form or the acceptance of which may, in the opinion of our counsel, be unlawful. We also reserve the absolute right to waive any condition to the exchange offer and any irregularities or conditions of tender as to particular outstanding bonds. Our interpretation of the terms and conditions of the exchange offer (including the instructions in the letter of transmittal) will be final and binding. Unless waived, any irregularities in connection with tenders must be cured within such time as we shall determine. We, along with the exchange agent, shall be under no duty to give notification of defects in such tenders and shall not

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incur liabilities for failure to give such notification. Tenders of outstanding bonds will not be deemed to have been made until those irregularities have been cured or waived. Any outstanding bonds received by the exchange agent that are not properly tendered and as to which the irregularities have not been cured or waived will be returned by the exchange agent to the tendering holder, unless otherwise provided in the letter of transmittal, as soon as practicable following the expiration date.

         Letters of transmittal and outstanding bonds must be sent only to the exchange agent. Do not send letters of transmittal or outstanding bonds to us or DTC.

        The method of delivery of outstanding bonds, letters of transmittal, any required signature guarantees and all other required documents, including delivery through DTC and any acceptance through ATOP, is at the election and risk of the persons tendering and delivering acceptances or letters of transmittal and, except as otherwise provided in the letter of transmittal, delivery will be deemed made only when actually received by the exchange agent. If delivery is by mail, it is suggested that the holder use properly insured, registered mail with return receipt requested, and that the mailing be made sufficiently in advance of the expiration date to permit delivery to the exchange agent prior to the expiration date.

Guaranteed Delivery Procedures

        DTC participants holding outstanding bonds through DTC who wish to cause their outstanding bonds to be tendered, but who cannot transmit their acceptances through ATOP prior to the expiration date, may cause a tender to be effected if:

Withdrawal Rights

        You may withdraw tenders of outstanding bonds, or any portion of your outstanding bonds, in integral multiples of $1,000 principal amount due at the stated maturity, at any time prior to 5:00 p.m., New York City time, on the expiration date. Any outstanding bonds properly withdrawn will be deemed to be not validly tendered for purposes of the exchange offer.

        DTC participants holding outstanding bonds who have transmitted their acceptances through ATOP may, prior to 5:00 p.m., New York City time, on the expiration date, withdraw the instruction

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given thereby by delivering to the exchange agent, at its address set forth under "—Exchange Agent," a written, telegraphic or facsimile notice of withdrawal of such instruction. Such notice of withdrawal must contain the name and number of the DTC participant, the principal amount of outstanding bonds to which such withdrawal relates and the signature of the DTC participant. Receipt of such written notice of withdrawal by the exchange agent effectuates a withdrawal.

        A withdrawal of a tender of outstanding bonds by a DTC participant or a holder, as the case may be, may be rescinded only by a new transmission of an acceptance through ATOP or execution and delivery of a new letter of transmittal, as the case may be, in accordance with the procedures described herein.

        A withdrawal of an instruction must be executed by a DTC participant in the same manner as the person's name appears on its transmission through ATOP to which such withdrawal relates. If a notice of withdrawal is signed by a trustee, partner, executor, administrator, guardian, attorney-in-fact, agent, officer of a corporation or other person acting in a fiduciary or representative capacity, such person must so indicate when signing and must submit with the revocation appropriate evidence of authority to execute the notice of withdrawal. A DTC participant may withdraw an instruction only if such withdrawal complies with the provisions of this prospectus.

        A withdrawal of a tender of outstanding bonds by a DTC participant may be rescinded only by a new transmission of an acceptance through ATOP in accordance with the procedures described herein.

Exchange Agent

        BNY Midwest Trust Company has been appointed as exchange agent for the exchange bonds. Questions, requests for assistance and requests for additional copies of this prospectus or of the letter of transmittal in connection with the exchange bonds should be directed to BNY Midwest Trust Company addressed as follows:

By Registered or Certified Mail :

The Bank of New York,
as Exchange Agent
The Bank of New York
Corporate Trust Operations Reorganization Unit
15 Broad Street, 16th Floor
New York, New York 10007

By Hand before 4:30 p.m. :

The Bank of New York
Corporate Trust Operations Reorganization Unit
15 Broad Street, 16th Floor
New York, NY 10007

By Hand after 4:30 p.m. or by Overnight Courier :

The Bank of New York
Corporate Trust Operations Reorganization Unit
15 Broad Street, 16/th/ Floor
New York, New York 10007
Facsimile: 212-235-[        ]
Telephone: 212-235-[        ]
Attention: [                                        ]

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Transfer Taxes

        Holders of outstanding bonds who tender their outstanding bonds for exchange bonds will not be obligated to pay any transfer taxes in connection therewith, except that holders who instruct us to register exchange bonds in the name of, or request that outstanding bonds not tendered or not accepted in the exchange offer be returned to, a person other than the registered tendering holder will be responsible for the payment of any applicable transfer tax thereon.


DESCRIPTION OF EXCHANGE BONDS

        In this description, the terms "ComEd," "Company," "we," "our," "ours" and "us" refer solely to Commonwealth Edison Company and not to any of our subsidiaries.

General

        The following statements are brief summaries of specified provisions of our Mortgage. The terms "lien of Mortgage," "mortgage date of acquisition," "permitted lien," "prior lien," "prior lien bonds," "property additions," and "utilized under the Mortgage" are used in this offering memorandum with the meanings given to those terms in the Mortgage. The term "bonds" means any first mortgage bonds issued under the Mortgage. The Mortgage contains provisions under which substantially all of the properties of our electric utility subsidiary, Commonwealth Edison Company of Indiana, Inc. (the "Indiana Company"), might be subjected to the lien of the Mortgage, if we should so determine, as additional security for our bonds, whereupon that subsidiary would become a "mortgaged subsidiary," as defined in the Mortgage. Since we have not as yet made any determination as to causing the Indiana Company to become a mortgaged subsidiary, those provisions of the Mortgage that are summarized below that discuss a mortgaged subsidiary as well as us, relate to us only.

Principal, Maturity and Interest

        The exchange bonds will initially be limited in aggregate principal amount to $600,000,000. The exchange bonds will be issued in book-entry form only in denominations of $1,000 and integral multiples thereof.

        The exchange bonds will mature on March 15, 2012. Interest will be payable on the exchange bonds semiannually on March 15 and September 15 of each year, commencing on September 15, 2002, until the principal is paid or made available for payment. Interest on the exchange bonds will accrue from the most recent date to which interest has been paid or, if no interest has been paid, from the date of issuance. Interest will be computed on the basis of a 360-day year comprised of twelve 30-day months.

        For so long as the exchange bonds are issued in book-entry form, payments of principal and interest will be made in immediately available funds by wire transfer to DTC or its nominee. If the exchange bonds are issued in certificated form to a holder other than DTC, payments of principal and interest will be made by check mailed to that holder at that holder's registered address. Payment of principal of the exchange bonds in certificated form will be made against surrender of those bonds at the office or agency of our company in the City of Chicago, Illinois and an office or agency in the Borough of Manhattan, City of New York. Payment of interest on the exchange bonds will be made to the person in whose name those exchange bonds are registered at the close of business on the record date for the relevant interest payment date, which shall be March 1 and September 1 for the interest payment dates on March 15 and September 15, respectively. Default interest will be paid in the same manner to holders as of a special record date established in accordance with the Mortgage.

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Redemption at Our Option

        We may, at our option, redeem the exchange bonds in whole or in part at any time at a redemption price equal to the greater of:

The redemption price will be calculated assuming a 360-day year consisting of twelve 30-day months.

        We will mail notice of any redemption at least 30 days but not more than 45 days before the redemption date to each registered holder of the exchange bonds to be redeemed.

        Unless we default in payment of the redemption price, on and after the redemption date, interest will cease to accrue on the exchange bonds or portions of the exchange bonds called for redemption.

        "Adjusted Treasury Rate" means, with respect to any redemption date, the rate per year equal to the semiannual equivalent yield to maturity of the Comparable Treasury Issue, assuming a price for the Comparable Treasury Issue (expressed as a percentage of its principal amount) equal to the Comparable Treasury Price for the redemption date.

        "Business Day" means any day that is not a day on which banking institutions in New York City are authorized or required by law or regulation to close.

        "Comparable Treasury Issue" means the United State Treasury security selected by the Quotation Agent as having a maturity comparable to the remaining term of the exchange bonds that would be used, at the time of selection and in accordance with customary financial practice, in pricing new issues of corporate debt securities of comparable maturity to the remaining term of the exchange bonds.

        "Comparable Treasury Price" means, with respect to any redemption date:

        "Quotation Agent" means the Reference Treasury Dealer appointed by us.

        "Reference Treasury Dealer" means

        "Reference Treasury Dealer Quotations" means, with respect to each Reference Treasury Dealer and any redemption date, the average, as determined by the trustee, of the bid and asked prices for the Comparable Treasury Issue (expressed in each case as a percentage of its principal amount) quoted in writing to the trustee by that Reference Treasury Dealer at 5:00 p.m., New York City time, on the third Business Day preceding that redemption date.

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Security

        The exchange bonds will rank equally with all bonds, irrespective of series, now or hereafter outstanding under our Mortgage. The Mortgage is a direct first mortgage lien on substantially all property and franchises currently owned by us, subject only to permitted liens (other than expressly excepted property and property which may be acquired by us subsequent to the filing of a bankruptcy proceeding with respect to us under the Bankruptcy Reform Act of 1978). Our transmission and distribution assets are the principal properties subject to the lien of the Mortgage. In addition, any property and franchises hereafter acquired by us (other than expressly excepted property and property which may be acquired by us subsequent to the filing of a bankruptcy proceeding with respect to us under the Bankruptcy Reform Act of 1978) will also become subject to the lien of the Mortgage, subject only to permitted liens and liens, if any, existing or placed on such after-acquired property at the time of acquisition thereof.

        There are expressly excepted from the lien of our Mortgage, whether now owned or hereafter acquired, specified real estate not used in the public utility business, real estate held by us in the name of a nominee, cash and securities not specifically pledged under the Mortgage, receivables, contracts (other than leases), materials and supplies not included in utility plant accounts, merchandise, automobiles, trucks and other transportation equipment and office furniture and equipment.

Acquisitions of Property Subject to Prior Liens

        We covenant in the Mortgage that we will not acquire any property subject to a prior lien:

        We also covenant that we will not transfer all or substantially all of our property to any other corporation, the property of which is subject to a prior lien, unless the property of such other corporation could be acquired by us under the provisions of such covenant with respect to the acquisition of property subject to a prior lien.

        We covenant in the Mortgage that we will not issue additional prior lien bonds under any prior lien, and that as soon as all prior lien bonds shall cease to be outstanding under any prior lien, we will promptly procure or cause to be procured the cancellation and discharge of that prior lien. We further covenant that upon the discharge of a prior lien we will cause any cash on deposit with the prior lien trustee (other than cash deposited for the payment or redemption of outstanding prior lien bonds) to be deposited with the Mortgage trustee, except to the extent required to be deposited with the trustee under another prior lien.

Release of Property from Mortgage

        Provided that we are not in default under the Mortgage, the Mortgage allows us to release property from the lien of the Mortgage in connection with its sale or other disposition. Under these provisions, we may obtain the release of mortgaged property by:

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        "Fair value" is defined as the fair value to us of the property in question. Fair value is determined by one of our engineers; however, a determination by an independent engineer is also required if the fair value of the property in question exceeds 1% or more of the outstanding principal amount of the bonds under the Mortgage. The required cash deposit may be reduced, or eliminated entirely, by utilizing net property additions or bondable bond retirements not previously utilized under the Mortgage.

        We have used these provisions from time to time to release substantial amounts of property from the lien of the Mortgage. In December 1999, we obtained the release of our fossil generation assets in connection with their sale to a third party. In January 2001, we obtained the release of, among other things, our nuclear generation assets in connection with their transfer to our affiliate, Exelon Generation Company, LLC, as part of the restructuring undertaken by Exelon. In both cases, the releases were accomplished without the deposit of cash due to the availability of sufficient amounts of unutilized bondable bond retirements and net property additions. In the event that our transmission assets were to be divested as part of our RTO efforts, we would expect to use these provisions to obtain the release of those assets from the lien of the Mortgage.

Issuance of Additional Bonds

        The Mortgage provides that no bonds may be issued which, as to security, will rank ahead of the exchange bonds but, as hereinafter indicated, we may, subject to certain limitations, acquire property subject to prior liens. Nonetheless, subject to the limitations discussed below, we may issue additional bonds under the Mortgage with the same priority as the exchange bonds, including bonds having the same series designation and terms as the exchange bonds, without the approval of the holders of bonds outstanding under the Mortgage, including the holders of the exchange bonds outstanding.

        The aggregate principal amount of other bonds that may be issued under the Mortgage and that, as to security, will rank equally with the exchange is not limited except as indicated below. Additional bonds of any series may be issued, subject to the provisions of the Mortgage, in principal amount equal to:

provided, however, that no bonds may be issued on the basis of net property additions or deposited cash, or on the basis of bondable bond retirements if the bonds to be issued bear a higher rate of interest than that borne by the bonds retired or being retired (except when the bonds retired or being retired mature within two years), unless our net earnings for any twelve-month period within the immediately preceding fifteen-month period shall have been equal to at least two and one-half times the annual interest on all bonds then outstanding under the Mortgage, including the bonds then proposed to be issued but not including any bonds then being retired. The net earnings calculation under the Mortgage is not affected by certain accounting write-offs related to plant costs.

        The Mortgage provides that cash deposited with the Mortgage trustee as a basis for the issuance of bonds shall be:

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        "Net Earnings" means our earnings as defined in the Mortgage after deducting all charges except:

Any net profit or net loss from merchandising and jobbing is to be deducted from operating expenses or added to operating expenses, as the case may be. Net nonoperating income from property and securities not subject to the lien of the Mortgage may be included in revenues but only to the extent of not more than 10% of the total of such net earnings. No profits or losses on the disposition of property or securities or on the reacquisition of securities shall be included in net earnings. The net earnings calculation under the Mortgage is not affected by certain accounting write-offs related to plant costs.

        Except as set forth above, the Mortgage does not limit the amount of additional bonds which can be issued and it does not contain any restrictions on the issuance of unsecured indebtedness. In addition, the Mortgage does not prohibit a merger or sale of substantially all of our assets or a comparable transaction, unless the lien of the Mortgage is impaired, and does not address the effect on bondholders of a highly leveraged transaction.

Property Additions/Bondable Bond Retirements

        The amount of net property additions not utilized under the Mortgage is currently approximately $2.141 billion. The amount of bondable bond retirements not previously utilized under the Mortgage is currently approximately $0.997 billion. We expect to issue the exchange bonds on the basis of bondable bond retirements.

        "Bondable bond retirements" means an amount equal to the principal amount of bonds retired by application of funds deposited with the Mortgage trustee for cancellation, whether or not such deposit of funds or surrender of bonds is pursuant to a sinking fund or purchase fund.

        "Net property additions" means the amount of $50,000,000, plus the cost or fair market value as of the mortgage date of acquisition thereof, whichever is less, of property additions, less all "current provisions for depreciation" made by us after December 1, 1944, after deducting from those current provisions for depreciation the amount of the "renewal fund requirement," if any, for the year 1945 and subsequent years.

        "Current provisions for depreciation" for any period means the greater of:

    •
    the total of the amounts appropriated by us for depreciation during that period on all property of the character of property additions not subject to a prior lien, increased or decreased, as the case may be, by net salvage value for that period, such amounts not to include, however, provisions for depreciation charged to surplus, charges to income or surplus for the amortization, write-down or write-off of acquisition adjustments or intangibles, property losses charged to operations or surplus, or charges to income in lieu of income and excess or other profits taxes; and

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    •
    an amount equal to one-twelfth of 2% for each calendar month of that period (or such lesser percentage, as may, at stated intervals, be certified by an independent engineer as adequate) of the original cost, as of the beginning of that month, of all depreciable property of the character of property additions not subject to a prior lien.

Renewal Fund Requirement

        We covenant in the Mortgage that we will, for each year, pay or cause to be paid to the Mortgage trustee an amount of cash, as and for a renewal fund, equal to the excess, if any, of current provisions for depreciation for that year over the cost or fair market value as of the mortgage date of acquisition thereof, whichever is less, of property additions for that year, that amount, which will be the renewal fund requirement for that year, to be subject to reduction by an amount equal to the amount, certified to the Mortgage trustee, of net property additions or bondable bond retirements, or both, not previously utilized under the Mortgage. There was no renewal fund requirement for any of the years 1945 through 1988, 1991, 1992 or 1997 through 2001. There was a $140.7 million renewal fund requirement for 1989, a $1 million requirement for 1990, a $50.9 million requirement for 1993, a $193.6 million requirement for 1994, a $15.0 million requirement for 1995 and a $139.9 million requirement for 1996. In 1989, 1990, 1993 and 1994, the renewal fund requirement was satisfied by certifying an equivalent amount of net property additions. In 1995 and 1996, the renewal fund requirement was satisfied by certifying an equivalent amount of bondable bond retirements.

Modification of Mortgage

        In general, modifications or alterations of the Mortgage and of the rights and obligations of us and of the bondholders, and waivers of compliance with the Mortgage, may, with our approval, be made at a meeting of bondholders upon the affirmative vote of 80% of the bonds entitled to vote at the meeting with respect to the matter involved, but no such modifications or alterations or waivers of compliance shall be made which will permit the extension of time or times of payment of the principal of or the interest or the premium, if any, on any bonds or the reduction in the principal amount thereof or in the rate of interest or the amount of any premium thereon, or any other modification in the terms of such principal, interest or premium, which terms of payment are unconditional, or, otherwise than as permitted by the Mortgage, the creation of any lien ranking prior to or on a parity with the lien of the Mortgage with respect to any of the mortgaged property, all as more fully provided in the Mortgage.

Concerning the Mortgage Trustee and the Co-Trustee

        An affiliate of the Mortgage trustee, BNY Midwest Trust Company, provides general banking services, including those as a depository, for us and certain of our subsidiaries and was one of the initial purchasers in the initial issuance of the outstanding bonds on March 13, 2002. D. G. Donovan, co-trustee under the Mortgage, is an officer of the Mortgage trustee.

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Rights Upon Default

        The Mortgage provides that in case any one or more of certain specified events (defined as "completed defaults") shall occur and be continuing, the Mortgage trustee or the holders of not less than 25% in principal amount of the bonds may declare the principal of all bonds, if not already due, together with all accrued and unpaid interest thereon, to be immediately due and payable. The Mortgage trustee upon request of the holders of a majority in principal amount of the bonds outstanding, shall waive such default and rescind any such declaration if such default is cured.

        The Mortgage further provides that upon the occurrence of one or more completed defaults, the Mortgage trustee and the co-trustee may proceed by such suits of law or in equity to foreclose the lien of the Mortgage or to enforce any other appropriate remedy as the Mortgage trustee and the co-trustee, being advised by counsel, shall determine.

        Holders of bonds have no right to enforce any remedy under the Mortgage unless the Mortgage trustee and the co-trustee have first had a reasonable opportunity to do so following notice of default to the Mortgage trustee and request by the holders of not less than 25% in principal amount of the bonds for action by the Mortgage trustee and the co-trustee with offer of indemnity satisfactory to the Mortgage trustee and the co-trustee against costs, expenses and liabilities that may be incurred thereby, but such provision does not impair the absolute right of any bondholder to enforce payment of the principal of and interest on such bondholder's bonds when due.

Default and Notice Thereof to Bondholders

        The Mortgage provides that the following shall constitute completed defaults:

    •
    default shall be made by us in the payment of any installment of interest on any of the bonds when due and such default shall continue for 60 days;

    •
    default shall be made by us in the payment of the principal of any of the bonds when due, whether at maturity or by declaration or otherwise;

    •
    default shall be made by us in the payment of any installment of interest on any prior lien bonds when due, and such default shall continue for 30 days after written notice given to us (following the expiration of the period of grace, if any, specified in the prior lien securing such prior lien bonds) by the Mortgage trustee or to us and the Mortgage trustee by the holders of not less than 5% in principal amount of the bonds;

    •
    default shall be made by us in the payment of the principal of any prior lien bonds when due, whether at maturity or by declaration or otherwise, and such default shall continue for 30 days after written notice to us by the Mortgage trustee or to us and the Mortgage trustee by the holders of not less than 5% in principal of the bonds;

    •
    bankruptcy, receivership or similar proceedings shall be initiated by us, or any judgment entered in such proceedings initiated against us shall not have been vacated, set aside or stayed within 45 days after the entry thereof; and

    •
    default shall be made in the observance or performance of any other of our covenants, conditions or agreements contained in the Mortgage or in the bonds or in any prior lien or prior lien bonds, and such default shall continue for 90 days after written notice to us and the Mortgage trustee by the holders of not less than 25% in principal amount of the bonds.

        Within 90 days after the occurrence of any default which is known to the Mortgage trustee and the co-trustee, the Mortgage trustee and the co-trustee shall give to the bondholders notice of such default unless it shall have been cured; except that, in case of defaults in the payment of principal of or interest on the bonds, or in the payment of any sinking fund or purchase fund installment, the

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Mortgage trustee shall in good faith determine that the withholding of such notice is in the interests of the bondholders and the co-trustee shall in good faith determine that the withholding of such notice is in the interests of the bondholders.

Certificates and Opinions

        Officers' certificates evidencing compliance with the covenants in the Mortgage relating to the payment of taxes and the maintenance of insurance on our properties subject to the lien of the Mortgage must be filed as exhibits to our certificate filed annually with the Mortgage trustee. In connection with the taking of various actions by the Mortgage trustee and the co-trustee, or the Mortgage trustee upon our application, including the authentication and delivery of additional bonds, the release of property, the reduction or withdrawal of cash and other matters, the Mortgage requires that we furnish to the Mortgage trustee orders, requests, resolutions, certificates of the officers, engineers, accountants and appraisers, and opinions of counsel and other documents, the particular documents to be furnished in each case being dependant upon the nature of the application.

Form, Denomination and Registration

        DTC will act as securities depository for the exchange bonds. The exchange bonds will be issued as fully registered bonds registered in the name of Cede & Co. (DTC's partnership nominee) or such other nominee as may be requested by an authorized representative of DTC. One fully registered bond certificate will be issued in the aggregate principal amount of the exchange bonds and will be deposited with DTC. So long as the nominee of DTC is the registered owner of the exchange bonds, such nominee will be considered the sole owner or holder of the exchange bonds for all purposes under the Mortgage and any applicable laws. Except as otherwise provided below, a beneficial owner of interests in the exchange bonds will not be entitled to have the exchange bonds registered in such owner's name, will not be entitled to receive a physical certificate representing such ownership interest and will not be considered an owner or holder of the exchange bonds under the Mortgage. Accordingly, each person owning a beneficial interest in an exchange bond must rely on the procedures of DTC and, if such person is not a participant, those of the participant through which that person owns its interest, in order to exercise any rights of a holder of the exchange bonds.

        The descriptions of the operations and procedures of DTC that follow are provided solely as a matter of convenience. These operations and procedures are solely within DTC's control and are subject to changes by DTC from time to time. We take no responsibility for these operations and procedures and urge you to contact DTC or its participants directly to discuss these matters. DTC has advised us as follows:

    •
    DTC is a limited-purpose trust company organized under the laws of the State of New York, a "banking organization" within the meaning of the New York Banking Law, a member of the Federal Reserve System, a "clearing corporation" within the meaning of the New York Uniform Commercial Code and a "clearing agency" registered pursuant to the provisions of Section 17A of the Exchange Act.

    •
    DTC was created to hold securities for its participants and to facilitate the clearance and settlement of securities transactions, such as transfers and pledges, among participants in deposited securities through electronic book-entry charges to accounts of its participants, thereby eliminating the need for physical movement of securities certificates.

    •
    Participants include securities brokers and dealers, banks, trust companies, clearing corporations and certain other organizations.

    •
    DTC is owned by a number of its participants and by the New York Stock Exchange, Inc., the American Stock Exchange LLC and the National Association of Securities Dealers, Inc.

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    •
    Access to the DTC system is also available to others such as securities brokers and dealers, banks and trust companies that clear through or maintain a custodial relationship with a participant, either directly or indirectly.

    •
    The rules applicable to DTC and its participants are on file with the SEC.

        Purchases of exchange bonds under the DTC system must be made by or through participants, who will receive a credit for the exchange bonds on DTC's records. The ownership interest of each actual purchaser of each exchange bond is in turn to be recorded on the participants' and indirect participants' records. Beneficial owners will not receive written confirmation from DTC of their purchase, but beneficial owners are expected to receive written confirmations providing details of the transactions, as well as periodic statements of their holdings, from the participant or indirect participant through which the beneficial owner entered into the transaction. Transfers of ownership interest in the exchange bonds are to be accomplished by entries made on the books of participants acting on behalf of beneficial owners. Beneficial owners will not receive certificates representing their ownership interests in the exchange bonds, except in the event that use of the book-entry system for the exchange bonds is discontinued.

        The deposit of the exchange bonds with a custodian for DTC and their registration in the name of Cede & Co. effect no change in beneficial ownership. DTC has no knowledge of the actual beneficial owners of the exchange bonds. DTC's records reflect only the identity of the participants to whose accounts such exchange bonds are credited, which may or may not be the beneficial owners. The participants will remain responsible for keeping account of their holdings on behalf of their customers.

        On each relevant payment date, we will wire transfer funds to DTC or its nominee, as the case may be, as the registered owner of the exchange bonds. Accordingly, neither we, the Mortgage trustee nor the initial purchasers will have any direct responsibility or liability to pay amounts due on the exchange bonds to owners of beneficial interests in the exchange bonds.

        DTC has advised us that its current practice, upon receipt of any payment of principal, premium, interest or the redemption or repurchase price, is to credit participants' accounts on the payment date in amounts proportionate to their respective beneficial interests in the global note as shown on DTC's records. In addition, it is DTC's current practice to assign any consenting or voting rights to participants whose accounts are credited with exchange bonds on a record date, by using an omnibus proxy. Payments by participants to owners of beneficial interests in the exchange bonds and voting by participants will be governed by standing instructions and customary practices between the participants and owners of beneficial interests, as is the case with securities held for the account of customers registered in "street name." But payments will be the responsibility of the participants and not of DTC, the Mortgage trustee or us.

        DTC may discontinue providing its services as securities depositary with respect to the exchange bonds at any time by giving us reasonable notice.

        We will be obligated to issue certificated exchange bonds with the same terms in authorized denominations only if:

    •
    DTC notifies us that it is unwilling or unable to continue as depositary or if DTC ceases to be a clearing agency registered under applicable law and a successor depositary is not appointed by us within 90 days;

    •
    we determine not to require all of the exchange bonds to be represented by one fully registered bond certificate and notify the Mortgage trustee of our decision; or

    •
    there shall have occurred and be continuing an event of default or any event which after notice or lapse of time or both would be an event of default with respect to the exchange bonds.

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        Although DTC has agreed to the foregoing procedures in order to facilitate transfers of beneficial ownership interests in the exchange bonds among participants, it is under no obligation to perform or to continue to perform those procedures, and those procedures may be discounted at any time.

        None of us, the Mortgage trustee or any of our respective agents will have any responsibility for the performance by DTC or its participants of their respective obligations under the rules and procedures governing its operations, including maintaining, supervising or reviewing the records relating to, or payments made on account of, beneficial ownership interests in exchange bonds.


SUMMARY OF UNITED STATES FEDERAL INCOME TAX CONSIDERATIONS

General

        The following discussion is a summary of United States federal income tax considerations relevant to the acquisition, ownership and disposition of the exchange bonds by beneficial owners thereof, or Bondholders, acquiring the exchange bonds in the exchange offer. This summary does not purport to be a complete discussion of all the potential United States federal income tax consequences relating to the acquisition, ownership and disposition of the exchange bonds by Bondholders. This summary does not address any tax consequences to holders of exchange bonds other than Bondholders who acquired the exchange bonds in the exchange offer. There can be no assurance that the Internal Revenue Service will take a similar view of those consequences. Further, the discussion does not address all aspects of taxation that may be relevant to particular Bondholders in light of their individual circumstances (including the effect of any foreign, state or local laws) or to certain types of purchasers subject to special treatment under United States federal income tax laws (including dealers in securities, insurance companies, financial institutions, pass-through entities, persons that hold securities that are a hedge or that are hedged against currency risks or that are part of a straddle or conversion transaction, persons whose functional currency is not the U.S. dollar, persons other than "United States persons," as defined for United States federal income tax purposes, and tax-exempt entities). The discussion below assumes that the exchange bonds are held as capital assets, and that the outstanding bonds given up in the exchange offer were acquired at original issue for their original "issue price."

        The discussion of the United States federal income tax consequences below is based on currently existing provisions of the Internal Revenue Code, judicial decisions, and administrative interpretations. Because individual circumstances may differ, each beneficial owner of outstanding bonds is strongly urged to consult its own tax advisor with respect to its particular tax situation and the particular tax effects of any state, local, non-U.S. or other tax laws and possible changes in the tax laws.

Treatment of Exchanges under Exchange Offer

        The exchange of the outstanding bonds for exchange bonds will not be a taxable event for United States federal income tax purposes. A Bondholder will not recognize any taxable gain or loss as a result of exchanging outstanding bonds for exchange bonds, and the holder will have the same tax basis and holding period in the exchange bonds as he had in the outstanding bonds immediately before exchange.

Payments of Interest

        Interest on an exchange bond generally will be taxable to a Bondholder as ordinary income at the time it accrues or is received, in accordance with the Bondholder's method of accounting for United States federal income tax purposes.

        If special interest is paid, although not free from doubt, such payment should be taxable to a beneficial owner as ordinary income at the time it accrues or is received in accordance with such owner's regular method of accounting. It is possible, however, that the Internal Revenue Service may take a different position, in which case the timing and amount of income inclusion may be different.

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        Under certain circumstances, we may be entitled to redeem all or a portion of the exchange bonds. Treasury Regulations contain special rules for determining the yield to maturity or maturity date of a debt instrument in the event the debt instrument provides for a contingency that could result in the acceleration or deferral of one or more payments. We do not believe that these rules are likely to apply to our right to redeem the exchange bonds. Therefore, we do not intend to treat such redemption provisions as affecting the computation of the yield to maturity or maturity date of the exchange bonds.

Sale, Exchange or Retirement of Bonds

        Upon the sale, exchange or retirement of an exchange bond, a Bondholder will recognize taxable gain or loss equal to the difference between the amount realized on the sale, exchange or retirement (not including any amount attributable to accrued but unpaid interest) and such Bondholder's adjusted tax basis in the exchange bond. A Bondholder's adjusted tax basis in an exchange bond generally will be equal to the cost of the exchange bond to such Bondholder.

        In general, gain or loss realized on the sale, exchange or retirement of an exchange bond by a Bondholder will be capital gain or loss, and will be long-term capital gain or loss if at the time of the sale, exchange or retirement, the Bondholder has held the exchange bond for more than one year. For a Bondholder who is an individual, long-term capital gain generally is taxed at a federal maximum rate of 20%. The distinction between capital gain or loss and ordinary income or loss is also relevant for purposes of, among other things, limitations on the deductibility of capital losses.

Information Reporting and Backup Withholding

        We will, where required, report to the holders of the exchange bonds and the Internal Revenue Service the amount of any interest paid on the exchange bonds in each calendar year and the amounts of federal income tax withheld, if any, with respect to payments. A noncorporate Bondholder may be subject to information reporting and to backup withholding with respect to payments of principal, premium, if any, and interest made on the exchange bonds, or on proceeds of the disposition of the exchange bonds before maturity, unless such Bondholder provides a correct taxpayer identification number or proof of an applicable exemption, and otherwise complies with applicable requirements of the information and backup withholding rules.

        Backup withholding is not an additional tax. Any amount withheld under the backup withholding rules will be refunded or credited against the Bondholder's federal income tax liability, provided that the required information is furnished to the Internal Revenue Service.

         The foregoing discussion is for general information only and is not tax advice. Accordingly, each prospective beneficial owner of an exchange bond should consult its own tax advisor as to the particular tax consequences to the prospective holder of purchasing, holding and disposing of the exchange bonds, including the applicability and effect of any state, local or non-United States income tax laws and any recent or prospective changes in applicable tax laws.


PLAN OF DISTRIBUTION

        Each broker-dealer that receives exchange bonds for its own account pursuant to the exchange offer must acknowledge that it will deliver a prospectus in connection with any resale of those exchange bonds. This prospectus, as it may be amended or supplemented from time to time, may be used by a broker-dealer in connection with resales of exchange bonds received in exchange for outstanding bonds where those outstanding bonds were acquired by such broker-dealer as a result of market-making activities or other trading activities. We have agreed that, starting on the expiration date and ending on the close of business one year after the expiration date, we will make this prospectus, as amended or supplemented, available to any broker-dealer for use in connection with any such resale. In addition, until [                                , 20    ], all dealers effecting transactions in the exchange bonds may be

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required to deliver a prospectus. Broker-dealers who acquired outstanding bonds directly from us may not rely on the staff's interpretations and must comply with the registration and prospectus delivery requirements of the Securities Act, including being named as a selling security holder, in order to resell the outstanding bonds or the exchange bonds.

        We will not receive any proceeds from any sale of exchange bonds by broker-dealers. Exchange bonds received by broker-dealers for their own account pursuant to the exchange offer may be sold from time to time in one or more transactions in the over-the-counter market, in negotiated transactions, through the writing of options on the exchange bonds or a combination of such methods of resale, at market prices prevailing at the time of resale, at prices related to such prevailing market prices or at negotiated prices. Any such resale may be made directly to purchasers or to or through brokers or dealers who may receive compensation in the form of commissions or concessions from any such broker-dealer and/or the purchasers of any such exchange bonds. Any broker-dealer that resells exchange bonds that were received by it for its own account pursuant to the exchange offer and any broker or dealer that participates in a distribution of such exchange bonds may be deemed to be an "underwriter" within the meaning of the Securities Act and any profit of any such resale of exchange bonds and any commissions or concessions received by any such persons may be deemed to be underwriting compensation under the Securities Act. The letter of transmittal states that, by acknowledging that it will deliver and by delivering a prospectus, a broker-dealer will not be deemed to admit that it is an "underwriter" within the meaning of the Securities Act.

        For a period of one year after the expiration date, we will promptly send additional copies of this prospectus and any amendment or supplement thereto to any broker-dealer that requests such documents in the letter of transmittal. We have agreed to pay all expenses incident to the exchange offer other than commissions or concessions of any brokers or dealers and will indemnify the holders of the bonds participating in the exchange offer against certain liabilities, including liabilities under the Securities Act.


LEGAL MATTERS

        Legal matters as to the validity of the exchange bonds offered by this prospectus will be passed upon for us by Sidley Austin Brown & Wood, Chicago, Illinois.


EXPERTS

        The financial statements of ComEd for the year ended December 31, 2001 and for the periods from January 1, 2000 to October 19, 2000 and October 20, 2000 to December 31, 2000 incorporated in this prospectus by reference to the Annual Report on Form 10-K of ComEd for the year ended December 31, 2001 have been so incorporated in reliance on the report of PricewaterhouseCoopers LLP, independent accountants, given on the authority of said firm as experts in auditing and accounting.

        The consolidated financial statements of income, cash flows, comprehensive income and changes in shareholders' equity of ComEd and consolidated subsidiaries, included in the Annual Report on Form 10-K for the year ended December 31, 1999 incorporated herein by reference, have been audited by Arthur Andersen LLP, independent accountants as stated in their report included in that Annual Report. Arthur Andersen LLP has not consented to the incorporation by reference of their report in this prospectus, and we have dispensed with the requirement to file their consent in reliance on Rule 437a promulgated under the Securities Act. Because Arthur Andersen LLP has not consented to the inclusion of its report in this prospectus, your ability to assert claims against Arthur Andersen LLP may be limited. In particular, because of this lack of consent, you will not be able to sue Arthur Andersen LLP under Section 11 of the Securities Act for any untrue statements of a material fact contained in the financial statements audited by Arthur Andersen LLP or any omissions to state a

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material fact required to be stated in those financial statements and therefore your right of recovery under that section may be limited.


WHERE YOU CAN FIND MORE INFORMATION

        We file annual, quarterly and current reports, information statements and other information with the Securities Exchange Commission. You may read and copy any document we file at the SEC's public reference room at 450 Fifth Street, N.W., Room 1024, Washington, D.C. 20549. You may obtain additional information about the public reference room by calling the SEC at 1-800-SEC-0330. In addition, the SEC maintains a site on the Internet ( http://www.sec.gov ) that contains reports, proxy statements and other information regarding issuers that file electronically with the SEC, including us.


INCORPORATION OF CERTAIN DOCUMENTS BY REFERENCE

        We are "incorporating by reference" information into this offering memorandum. This statement means that we are disclosing important information to you by referring you to another document that we have filed with the SEC. The information incorporated by reference is considered to be part of this offering memorandum. Information that we file with the SEC after the date of this offering memorandum will automatically modify and supersede the information included or incorporated by reference in this offering memorandum to the extent that the subsequently filed information modifies or supersedes the existing information. We incorporate by reference the following documents:

    •
    Our Annual Report on Form 10-K for the fiscal year ended December 31, 2001;

    •
    Our Quarterly Reports on Form 10-Q for the fiscal quarters ended March 31, 2002 and June 30, 2002; and

    •
    Our Current Reports on Form 8-K dated January 29, 2002, April 2, 2002, April 22, 2002, May 17, 2002, July 16, 2002, July 31, 2002, August 27, 2002 and September 3, 2002.

We also incorporate by reference all future filings we make with the SEC under sections 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934 until the termination of the exchange offer.

        In addition to the resources maintained by the SEC, you may also access these filings by contacting us at Commonwealth Edison Company, 10 South Dearborn Street, 37th Floor, P.O. Box 805379, Chicago, Illinois 60680-5379; Attention: Director, Investor Relations.

35


Exchange Offer for

$600,000,000
First Mortgage 6.15% Bonds, Series 98
Due March 15, 2012

COMED LOGO

PROSPECTUS

                        , 2002


PART II

INFORMATION NOT REQUIRED IN THE PROSPECTUS

ITEM 20. INDEMNIFICATION OF DIRECTORS AND OFFICERS.

        Certain provisions of the Illinois Business Corporation Act of 1983, as amended (the "BCA"), provide that the Registrant may, and in some circumstances must, indemnify the directors and officers of the Registrant and of each subsidiary company against liabilities and expenses incurred by such person by reason of the fact that such person was serving in such capacity, subject to certain limitations and conditions set forth in the statute. The Registrant's Restated Articles of Incorporation and By-Laws provide that the Registrant will indemnify its directors and officers, and may indemnify any person serving as director or officer of another business entity at the Registrant's request, to the extent permitted by the statute. In addition, the Registrant's Restated Articles of Incorporation provide, as permitted by the BCA, that directors shall not be personally liable for monetary damages for breach of fiduciary duty as a director, except (i) for breaches of their duty of loyalty to the Registrant or its shareholders, (ii) for acts or omissions not in good faith or which involve intentional misconduct or a knowing violation of law, (iii) under Section 8.65 of the BCA, and (iv) for transactions from which a director derived an improper personal benefit.

        The Registrant maintains liability insurance policies which indemnify the Registrant's directors and officers, the directors and officers of subsidiaries of the Registrant, and the trustees of the Commonwealth Edison Company Service Annuity Fund and the Commonwealth Edison Company of Indiana, Inc. Service Annuity Fund, against loss arising from claims by reason of their legal liability for acts as such directors, officers or trustees, subject to limitations and conditions as set forth in the policies.


ITEM 21. EXHIBITS AND FINANCIAL STATEMENTS INDEX.

    (a)
    Exhibits:

Exhibits No.
  Description
3-1   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).

3-2
 
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
 
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).

4-1-1
 
Supplemental Indentures to the aforementioned Commonwealth Edison Mortgage are incorporated herein by reference or filed herewith as follows:

 

 
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

II-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 21, 1993   4-1
    July 15, 1993   1-1839, Form 10-Q for quarter ended June 30, 1993   4-1
    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
    May 20, 2002   333-99363, Form S-3   4-4-1
    June 1, 2002   333-99363, Form S-3   4-4-1

II-2

4-1-2   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 is incorporated by reference to Exhibit 4-4-2 to Commonwealth Edison Company's 2001 Form 10-K (File No. 1-1839).

4-1-3*
 
Form of Supplemental Mortgage Indenture for the Exchange Bonds.

4-2*
 
Purchase Agreement dated March 6, 2002 among ComEd and the representatives of the Initial Purchasers.

4-3*
 
Purchase Agreement dated June 13, 2002 among ComEd and the representatives of the Initial Purchasers.

4-4*
 
Registration Rights Agreement dated March 13, 2002 among ComEd and the representatives of the Initial Purchasers.

4-5*
 
Registration Rights Agreement dated June 20, 2002 among ComEd and the representatives of the Initial Purchasers.

4-6*
 
Form of Exchange Bond.

5-1*
 
Opinion of Sidley Austin Brown & Wood.

8-1*
 
Opinion of Sidley Austin Brown & Wood.

23-1*
 
Consent of PricewaterhouseCoopers LLP

24-1*
 
Power of Attorney (set forth on the signature pages to this Registration Statement).

25-1*
 
Statement regarding eligibility of Trustee on Form T-1 of BNY Midwest Trust Company.

25-2*
 
Statement regarding eligibility of Trustee on Form T-2 of D.G. Donovan.

99-1*
 
Form of Letter of Transmittal.

99-2*
 
Form of Notice of Guaranteed Delivery.
*
Filed Herewith

(b)
Financial Schedules:

        None


ITEM 22. UNDERTAKINGS.

        The undersigned Registrants hereby undertake that:

            (a)  For purposes of determining any liability under the Securities Act of 1933, each filing of the registrant's annual report pursuant to section 13(a) or section 15(d) of the Securities Exchange Act of 1934 that is incorporated by reference in this registration statement shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

            (b)  To deliver or cause to be delivered with the prospectus, to each person to whom the prospectus is sent or given, the latest annual report to security holders that is incorporated by reference in the prospectus and furnished pursuant to and meeting the requirements of Rule 14a-3 or Rule 14c-3 under the Securities Exchange Act of 1934; and, where interim financial information required to be presented by Article 3 of Regulation S-X are not set forth in the prospectus, to deliver, or cause to be delivered to each person to whom the prospectus is sent or given, the latest

II-3


    quarterly report that is specifically incorporated by reference in the prospectus to provide such interim financial information.

            (c)  Insofar as indemnification for liabilities arising under the Securities Act of 1933 may be permitted to directors, officers and controlling persons of the registrant pursuant to the foregoing provisions, or otherwise, the registrant has been advised that in the opinion of the Securities and Exchange Commission such indemnification is against public policy as expressed in the Securities Act and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the registrant of expenses incurred or paid by a director, officer or controlling person of the registrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the registrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Act and will be governed by the final adjudication of such issue.

            (d)  To respond to requests for information that is incorporated by reference into the prospectus pursuant to Item 4, 10(b), 11 or 13 of this Form, within one business day of receipt of such request, and to send the incorporated documents by first class mail or other equally prompt means. This undertaking includes information contained in documents filed subsequent to the effective date of this registration statement through the date of responding to the request.

            (e)  To supply by means of a post-effective amendment all information concerning a transaction and the company being acquired involved therein, that was not the subject of and included in this registration statement when it became effective.

II-4


SIGNATURES

        Pursuant to the requirements of the Securities Act of 1933, the Registrant has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized in the City of Chicago, State of Illinois, on the 18 th day of September, 2002.

    COMMONWEALTH EDISON COMPANY

 
 
By:
 
/s/   ROBERT E. BERDELLE       
    Name:   Robert E. Berdelle
    Title:   Vice President, Finance and
Chief Financial Officer

Power of Attorney

        Each person whose signature appears below hereby constitutes and appoints John W. Rowe and Robert E. Berdelle and each acting alone, his or her true and lawful attorneys-in-fact and agents, with full power of substitution and resubstitution, for him or her and in his or her name, place and stead, in any and all capacities, to sign any or all amendments or supplements to this Registration Statement and to file the same with all exhibits thereto and other documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorneys-in-fact and agents full power and authority to do and perform each and every act and thing necessary or appropriate to be done with this Registration Statement and any amendments or supplements hereto, as fully to all intents and purposes as he might or could do in person, hereby ratifying and confirming all that said attorneys-in-fact and agents, or their substitute or substitutes, may lawfully do or cause to be done by virtue hereof.

        Pursuant to the requirements of the Securities Act of 1933, this Registration Statement has been signed by the following persons in the capacities and on the dates indicated.

Signature
  Title
  Date

 
 
 
 
 
/s/   ROBERT E. BERDELLE       
Robert E. Berdelle 		  Vice President and Chief
Financial Officer (principal
financial and accounting officer) 		  September 18, 2002

/s/   FRANK M. CLARK       
Frank M. Clark
 
President and Director
 
September 18, 2002

/s/   RUTH ANN M. GILLIS       
Ruth Ann M. Gillis
 
Director
 
September 18, 2002

/s/   KENNETH G. LAWRENCE       
Kenneth G. Lawrence
 
Director
 
September 18, 2002

/s/   JOHN W. ROWE       
John W. Rowe
 
Director
 
September 18, 2002

/s/   PAMELA B. STROBEL       
Pamela B. Strobel
 
Chairman of the Board and Director
 
September 18, 2002

II-5



QuickLinks

TABLE OF CONTENTS
PROSPECTUS SUMMARY
RISK FACTORS
SUMMARY FINANCIAL INFORMATION
USE OF PROCEEDS
THE EXCHANGE OFFER
DESCRIPTION OF EXCHANGE BONDS
SUMMARY OF UNITED STATES FEDERAL INCOME TAX CONSIDERATIONS
PLAN OF DISTRIBUTION
LEGAL MATTERS
EXPERTS
WHERE YOU CAN FIND MORE INFORMATION
INCORPORATION OF CERTAIN DOCUMENTS BY REFERENCE
PART II INFORMATION NOT REQUIRED IN THE PROSPECTUS
SIGNATURES

EXHIBIT 4.1.3.

This instrument was prepared by,
and when recorded should be
returned to:

Richard W. Astle
Sidley Austin Brown & Wood
Bank One Plaza
10 South Dearborn Street
Chicago, Illinois 60603

SUPPLEMENTAL INDENTURE

Dated as of ________________, 2002

COMMONWEALTH EDISON COMPANY

to

BNY MIDWEST TRUST COMPANY

and

D. G. DONOVAN

Trustees under Mortgage Dated July 1, 1923, and Certain Indentures Supplemental Thereto

Providing for Issuance of

FIRST MORTGAGE 6.15% BONDS, SERIES 98
DUE MARCH 15, 2012

THIS SUPPLEMENTAL INDENTURE, dated as of _____________, 2002, between COMMONWEALTH EDISON COMPANY, a corporation organized and existing under the laws of the State of Illinois (hereinafter called the "COMPANY") having an address at 10 South Dearborn Street, 37th floor, Chicago, Illinois 60603, party of the first part, and BNY MIDWEST TRUST COMPANY, a trust company organized and existing under the laws of the State of Illinois having an address at 2 North LaSalle Street, Suite 1020, Chicago, Illinois 60602, and D.G. DONOVAN, an individual having an address at 2 North LaSalle Street, Suite 1020, Chicago, Illinois 60602, as Trustee and Co-Trustee, respectively, under the Mortgage of the Company dated July 1, 1923, as amended and supplemented by Supplemental Indenture dated August 1, 1944 and the subsequent supplemental indentures hereinafter mentioned, parties of the second part (said Trustee being hereinafter called the "TRUSTEE", the Trustee and said Co-Trustee being hereinafter together called the "TRUSTEES", and said Mortgage dated July 1, 1923, as amended and supplemented by said Supplemental Indenture dated August 1, 1944 and subsequent supplemental indentures, being hereinafter called the "MORTGAGE"),

W I T N E S S E T H:

WHEREAS, the Company duly executed and delivered the Mortgage to provide for the issue of, and to secure, its bonds, issuable in series and without limit as to principal amount except as provided in the Mortgage; and

WHEREAS, the Company from time to time has executed and delivered supplemental indentures to the Mortgage to provide for (i) the creation of additional series of bonds secured by the Mortgage, (ii) the amendment of certain of the terms and provisions of the Mortgage and (iii) the confirmation of the lien of the Mortgage upon property of the Company, such supplemental indentures that are currently effective and the respective dates, parties thereto and purposes thereof, being as follows: 

SUPPLEMENTAL INDENTURE
DATE                       PARTIES                                         PROVIDING FOR
August 1, 1944             Company to Continental Illinois National Bank   Amendment and restatement of
                           and Trust Company of Chicago and Edmond B.      Mortgage dated July 1, 1923
                           Stofft, as Trustee and Co-Trustee

August 1, 1946             Company to Continental Illinois National Bank   Confirmation of mortgage lien
                           and Trust Company of Chicago and Edmond B.
                           Stofft, as Trustee and Co-Trustee

April 1, 1953              Company to Continental Illinois National Bank   Confirmation of mortgage lien
                           and Trust Company of Chicago and Edmond B.
                           Stofft, as Trustee and Co-Trustee

March 31, 1967             Company to Continental Illinois National Bank   Confirmation of mortgage lien
                           and Trust Company of Chicago and Edward J.
                           Friedrich, as Trustee and Co-Trustee

April 1, 1967              Company to Continental Illinois National Bank   Amendment of Sections 3.01, 3.02,
                           and Trust Company of Chicago and                3.05 and 3.14 of the


                                   -1-

                           Edward J. Friedrich, as Trustee and             Mortgage and issuance of First
                           Co-Trustee                                      Mortgage 5-3/8% Bonds, Series Y

February 28, 1969          Company to Continental Illinois National Bank   Confirmation of mortgage lien
                           and Trust Company of Chicago and Donald W.
                           Alfvin, as Trustee and Co-Trustee

May 29, 1970               Company to Continental Illinois National Bank   Confirmation of mortgage lien
                           and Trust Company of Chicago and Donald W.
                           Alfvin, as Trustee and Co-Trustee

June 1, 1971               Company to Continental Illinois National Bank   Confirmation of mortgage lien
                           and Trust Company of Chicago and Donald W.
                           Alfvin, as Trustee and Co-Trustee

April 1, 1972              Company to Continental Illinois National Bank   Confirmation of mortgage lien
                           and Trust Company of Chicago and Donald W.
                           Alfvin, as Trustee and Co-Trustee

May 31, 1972               Company to Continental Illinois National Bank   Confirmation of mortgage lien
                           and Trust Company of Chicago and Donald W.
                           Alfvin, as Trustee and Co-Trustee

June 15, 1973              Company to Continental Illinois National Bank   Confirmation of mortgage lien
                           and Trust Company of Chicago and Donald W.
                           Alfvin, as Trustee and Co-Trustee

May 31, 1974               Company to Continental Illinois National Bank   Confirmation of mortgage lien
                           and Trust Company of Chicago and Donald W.
                           Alfvin, as Trustee and Co-Trustee

June 13, 1975              Company to Continental Illinois National Bank   Confirmation of mortgage lien
                           and Trust Company of Chicago and Donald W.
                           Alfvin, as Trustee and Co-Trustee

May 28, 1976               Company to Continental Illinois National Bank   Confirmation of mortgage lien
                           and Trust Company of Chicago and Donald W.
                           Alfvin, as Trustee and Co-Trustee

June 3, 1977               Company to Continental Illinois National Bank   Confirmation of mortgage lien
                           and Trust Company of Chicago and Donald W.
                           Alfvin, as Trustee and Co-Trustee

May 17, 1978               Company to Continental Illinois National Bank   Confirmation of mortgage lien
                           and Trust Company of Chicago and Donald W.
                           Alfvin, as Trustee and Co-Trustee

August 31, 1978            Company to Continental Illinois National Bank   Confirmation of mortgage lien
                           and Trust Company of Chicago and Donald W.
                           Alfvin, as Trustee and Co-Trustee

June 18, 1979              Company to Continental Illinois National Bank   Confirmation of mortgage lien
                           and Trust Company of Chicago and Donald W.
                           Alfvin, as Trustee and Co-Trustee


                                   -2-

June 20, 1980              Company to Continental Illinois National Bank   Confirmation of mortgage lien
                           and Trust Company of Chicago and Donald W.
                           Alfvin, as Trustee and Co-Trustee

April 16, 1981             Company to Continental Illinois National Bank   Confirmation of mortgage lien
                           and Trust Company of Chicago and Donald W.
                           Alfvin, as Trustee and Co-Trustee

April 30, 1982             Company to Continental Illinois National Bank   Confirmation of mortgage lien
                           and Trust Company of Chicago and Donald W.
                           Alfvin, as Trustee and Co-Trustee

April 15, 1983             Company to Continental Illinois National Bank   Confirmation of mortgage lien
                           and Trust Company of Chicago and Donald W.
                           Alfvin, as Trustee and Co-Trustee

April 13, 1984             Company to Continental Illinois National Bank   Confirmation of mortgage lien
                           and Trust Company of Chicago and Donald W.
                           Alfvin, as Trustee and Co-Trustee

April 15, 1985             Company to Continental Illinois National Bank   Confirmation of mortgage lien
                           and Trust Company of Chicago and Donald W.
                           Alfvin, as Trustee and Co-Trustee

April 15, 1986             Company to Continental Illinois National Bank   Confirmation of mortgage lien
                           and Trust Company of Chicago and M.J. Kruger,
                           as Trustee and Co-Trustee

June 15, 1990              Company to Continental Bank, National           Issuance of First Mortgage 9-7/8%
                           Association and M.J. Kruger, as Trustee and     Bonds, Series 75
                           Co-Trustee

June 1, 1991               Company to Continental Bank, National           Issuance of First Mortgage Bonds,
                           Association and M.J. Kruger, as Trustee and     Pollution Control Series 1991
                           Co-Trustee

October 1, 1991            Company to Continental Bank, National           Issuance of First Mortgage 8-1/4%
                           Association and M.J. Kruger, as Trustee and     Bonds, Series 76 and First
                           Co-Trustee                                      Mortgage 8-7/8% Bonds, Series 77

October 15, 1991           Company to Continental Bank, National           Issuance of First Mortgage 8-3/8%
                           Association and M.J. Kruger, as Trustee and     Bonds, Series 78 and First
                           Co-Trustee                                      Mortgage 9-1/8% Bonds, Series 79

February 1, 1992           Company to Continental Bank, National           Issuance of First Mortgage 7%
                           Association and M.J. Kruger, as Trustee and     Bonds, Series 80 and First
                           Co-Trustee                                      Mortgage 8-5/8% Bonds, Series 81

May 15, 1992               Company to Continental Bank, National           Issuance of First Mortgage 6-1/8%
                           Association and M.J. Kruger, as Trustee and     Bonds, Series 82 and First
                           Co-Trustee                                      Mortgage 8% Bonds, Series 83


                                   -3-

July 15, 1992              Company to Continental Bank, National           Issuance of First Mortgage 8-1/2%
                           Association and M.J. Kruger, as Trustee and     Bonds, Series 84
                           Co-Trustee

September 15, 1992         Company to Continental Bank, National           Issuance of First Mortgage 7-3/8%
                           Association and M.J. Kruger, as Trustee and     Bonds, Series 85 and First
                           Co-Trustee                                      Mortgage 8-3/8% Bonds, Series 86

February 1, 1993           Company to Continental Bank, National           Issuance of First Mortgage 8-3/8%
                           Association and M.J. Kruger, as Trustee and     Bonds, Series 88
                           Co-Trustee

April 1, 1993              Company to Continental Bank, National           Issuance of First Mortgage 6-1/2%
                           Association and M.J. Kruger, as Trustee and     Bonds, Series 90 and First
                           Co-Trustee                                      Mortgage 8% Bonds, Series 91

April 15, 1993             Company to Continental Bank, National           Issuance of First Mortgage 7-5/8%
                           Association and M.J. Kruger, as Trustee and     Bonds, Series 92
                           Co-Trustee

June 15, 1993              Company to Continental Bank, National           Issuance of First Mortgage 7%
                           Association and M.J. Kruger, as Trustee and     Bonds, Series 93 and First
                           Co-Trustee                                      Mortgage 7-1/2% Bonds, Series 94

July 15, 1993              Company to Continental Bank, National           Issuance of First Mortgage 6-5/8%
                           Association and M.J. Kruger, as Trustee and     Bonds, Series 96 and First
                           Co-Trustee                                      Mortgage 7-3/4% Bonds, Series 97

January 15, 1994           Company to Continental Bank, National           Issuance of First Mortgage Bonds,
                           Association and M.J. Kruger, as Trustee and     Pollution Control Series 1994A,
                           Co-Trustee                                      1994B and 1994C

December 1, 1994           Company to Bank of America Illinois and         Issuance of First Mortgage Bonds,
                           Robert J. Donahue, as Trustee and Co-Trustee    Pollution Control Series 1994D

June 1, 1996               Company to Harris Trust and Savings Bank and    Issuance of First Mortgage Bonds,
                           D.G. Donovan, as Trustee and Co-Trustee         Pollution Control Series 1996A and
                                                                           1996B

March 1, 2002              Company to BNY Midwest Trust Company and D.G.   Issuance of First Mortgage 6.15%
                           Donovan, as Trustee and Co-Trustee              Bonds, Series 98

May 20, 2002               Company to BNY Midwest Trust Company and D.G.   Issuance of First Mortgage Bonds,
                           Donovan, as Trustee and Co-Trustee              Pollution Control Series 2002

June 1, 2002               Company to BNY Midwest Trust Company and D.G.   Issuance of additional First
                           Donovan, as Trustee and Co-Trustee              Mortgage 6.15% Bonds, Series 98

-4-

WHEREAS, the respective designations, maturity dates and principal amounts of the bonds of each series presently outstanding under, and secured by, the Mortgage and the several supplemental indentures above referred to, are as follows: 

               DESIGNATION                               MATURITY DATE                        PRINCIPAL AMOUNT

First Mortgage 9-7/8% Bonds, Series 75                 June 15, 2020                           $   54,171,000

First Mortgage 8-1/4% Bonds, Series 76                 October 1, 2006                            100,000,000

First Mortgage 8-3/8% Bonds, Series 78                 October 15, 2006                           125,000,000

First Mortgage 8-5/8% Bonds, Series 81                 February 1, 2022                           200,000,000

First Mortgage 8% Bonds, Series 83                     May 15, 2008                               140,000,000

First Mortgage 8-1/2% Bonds, Series 84                 July 15, 2022                              200,000,000

First Mortgage 7-3/8% Bonds, Series 85                 September 15, 2002                         200,000,000

First Mortgage 8-3/8% Bonds, Series 86                 September 15, 2022                         200,000,000

First Mortgage 8-3/8% Bonds, Series 88                 February 15, 2023                          235,950,000

First Mortgage 8% Bonds, Series 91                     April 15, 2023                             160,000,000

First Mortgage 7-5/8% Bonds, Series 92                 April 15, 2013                             220,000,000

First Mortgage 7% Bonds, Series 93                     July 1, 2005                               225,000,000

First Mortgage 7-1/2% Bonds, Series 94                 July 1, 2013                               150,000,000

First Mortgage 6-5/8% Bonds, Series 96                 July 15, 2003                              100,000,000

First Mortgage 7-3/4% Bonds, Series 97                 July 15, 2023                              150,000,000

First Mortgage 5.3% Bonds, Pollution Control Series    June 1, 2011                               100,000,000
1991

First Mortgage 5.3% Bonds, Pollution Control Series    January 15, 2004                            26,000,000
1994A

First Mortgage 5.7% Bonds, Pollution Control Series    January 15, 2009                            20,000,000
1994B

First Mortgage 5.85% Bonds, Pollution Control Series   January 15, 2014                            20,000,000
1994C

First Mortgage 6.75% Bonds, Pollution Control Series   March 1, 2015                               91,000,000
1994D

First Mortgage 4.4% Bonds, Pollution Control Series    December 1, 2006                           110,000,000
1996A

First Mortgage 4.4% Bonds, Pollution Control Series    December 1, 2006                            89,400,000
1996B

First Mortgage 6.15% Bonds, Series 98                  March 15, 2012                             400,000,000


                                       -5-

First Mortgage Bonds, Pollution Control Series 2002    April 15, 2013                             100,000,000

First Mortgage 6.15% Bonds, Series 98                  March 15, 2012                             200,000,000
                                                                                     -------------------------
                                                       Total                                   $3,516,521,000
                                                                                     =========================

WHEREAS, on March 13, 2002, the Company issued $400,000,000 aggregate principal amount of its First Mortgage 6.15% Bonds, Series 98, due March 15, 2012 pursuant to the provisions of a Supplemental Indenture dated as of March 1, 2002, and on June 20, 2002, the Company issued an additional $200,000,000 aggregate principal amount of its First Mortgage 6.15% Bonds, Series 98, due March 15, 2012 pursuant to the provisions of a Supplemental Indenture dated as of June 1, 2002 (such bonds are collectively referred to herein as the "ORIGINAL BONDS"); and

WHEREAS, in connection with the issuances of the Original Bonds, the Company entered into Registration Rights Agreements dated as of March 13, 2002 and June 20, 2002, between the Company and the representatives of the initial purchasers of the Original Bonds, pursuant to which the Company agreed (i) to register $600,000,000 aggregate principal amount of its First Mortgage 6.15% Bonds, Series 98, due March 15, 2012 (the "EXCHANGE BONDS") and (ii) to exchange the Original Bonds for the Exchange Bonds in an exchange offer (the "EXCHANGE OFFER"); and

WHEREAS, the Exchange Offer having been completed, the Company wishes to issue the Exchange Bonds issuable in connection with said Exchange Offer; and

WHEREAS, the Company desires, by this Supplemental Indenture, to provide for the issuance of the Exchange Bonds under the Mortgage, such bonds to be designated "First Mortgage 6.15% Bonds, Series 98" and the terms and provisions to be contained in the Exchange Bonds or to be otherwise applicable thereto to be as set forth in this Supplemental Indenture; and

WHEREAS, the Exchange Bonds and the Trustee's certificate to be endorsed thereon shall be substantially in the form of the General Form of Registered Bond Without Coupons and the form of the General Form of Trustee's Certificate set forth in Section 3.05 of the Supplemental Indenture dated August 1, 1944 to the Mortgage with such appropriate insertions, omissions and variations in order to express the designation, date, maturity date, annual interest rate, record dates for, and dates of, payment of interest, denominations, terms of redemption and redemption prices, and other terms and characteristics authorized or permitted by the Mortgage or not inconsistent therewith; and

WHEREAS, the Company is legally empowered and has been duly authorized by the necessary corporate action and by order of the Illinois Commerce Commission to make, execute and deliver this Supplemental Indenture, and to provide for the issuance of the Exchange Bonds, and all acts and things whatsoever necessary to make this Supplemental Indenture, when

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executed and delivered by the Company and the Trustees, a valid, binding and legal instrument, and to make the Exchange Bonds, when authenticated by the Trustee and issued as in the Mortgage and in this Supplemental Indenture provided, the valid, binding and legal obligations of the Company, entitled in all respects to the security of the Mortgage, as amended and supplemented, have been done and performed;

NOW, THEREFORE, in consideration of the premises and of the sum of one dollar duly paid by the Trustees to the Company, and for other good and valuable consideration, the receipt of which is hereby acknowledged, the parties hereto do hereby agree as follows:

SECTION 1. DESIGNATION AND ISSUANCE OF EXCHANGE BONDS. The Exchange Bonds shall, as hereinbefore recited, be designated as the Company's "First Mortgage 6.15% Bonds, Series 98." Subject to the provisions of the Mortgage, the Exchange Bonds shall be issuable without limitation as to the aggregate principal amount thereof. The Exchange Bonds are identical in all material respects to the Original Bonds (except that the interest rate step-up provisions and the transfer restrictions shall be modified or eliminated, as appropriate) and shall constitute a single series of bonds under the Mortgage.

SECTION 2. FORM, DATE, MATURITY DATE, INTEREST RATE AND INTEREST PAYMENT DATES OF EXCHANGE BONDS. (a) The definitive Exchange Bonds shall be in engraved, lithographed, printed or typewritten form and shall be registered bonds without coupons; and such bonds and the Trustee's certificate to be endorsed thereon shall be substantially in the forms hereinbefore recited, respectively. The Exchange Bonds shall be dated as provided in Section 3.01 of the Mortgage, as amended by Supplemental Indenture dated April 1, 1967.

(b) The Exchange Bonds shall mature on March 15, 2012.

(c) The Exchange Bonds shall bear interest at the rate of 6.15% per annum until the principal thereof shall be paid.

(d) Interest on the Exchange Bonds shall be payable semi-annually on the fifteenth day of March and the fifteenth day of September in each year, commencing ________, 200__. March 1 and September 1 in each year are hereby established as record dates for the payment of interest payable on the next succeeding interest payment dates, respectively. The interest on each Exchange Bond so payable on any interest payment date shall, subject to the exceptions provided in Section 3.01 of the Mortgage, as amended by said Supplemental Indenture dated April 1, 1967, be paid to the person in whose name such bond is registered at the close of business on the March 1 or September 1, as the case may be, next preceding such interest payment date.

SECTION 3. EXECUTION OF EXCHANGE BONDS. The Exchange Bonds shall be executed on behalf of the Company by its President or one of its Vice Presidents, manually or by facsimile signature, and shall have its corporate seal affixed thereto or a facsimile of such seal imprinted thereon, attested by its Secretary or one of its Assistant Secretaries, manually or by facsimile signature, all as may be provided by resolution of the Board of Directors of the Company. In

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case any officer or officers whose signature or signatures, manual or facsimile, shall appear upon any Exchange Bond shall cease to be such officer or officers before such bond shall have been actually authenticated and delivered, such bond nevertheless may be issued, authenticated and delivered with the same force and effect as though the person or persons whose signature or signatures, manual or facsimile, appear thereon had not ceased to be such officer or officers of the Company.

SECTION 4. MEDIUM AND PLACES OF PAYMENT OF PRINCIPAL OF AND INTEREST ON EXCHANGE BONDS; TRANSFERABILITY AND EXCHANGEABILITY. Both the principal of and interest on the Exchange Bonds shall be payable in any coin or currency of the United States of America which at the time of payment is legal tender for the payment of public and private debts, and both such principal and interest shall be payable at the office or agency of the Company in the City of Chicago, State of Illinois, or, at the option of the registered owner, at the office or agency of the Company in the Borough of Manhattan, The City of New York, State of New York, and such bonds shall be transferable and exchangeable, in the manner provided in Sections 3.09 and 3.10 of the Mortgage, at said office or agency. No charge shall be made by the Company to the registered owner of any Exchange Bond for the transfer of such bond or for the exchange thereof for bonds of other authorized denominations, except, in the case of transfer, a charge sufficient to reimburse the Company for any stamp or other tax or governmental charge required to be paid by the Company or the Trustee.

SECTION 5. DENOMINATIONS AND NUMBERING OF EXCHANGE BONDS. The Exchange Bonds shall be issued in the denomination of $1,000 and in such multiples of $1,000 as shall from time to time hereafter be determined and authorized by the Board of Directors of the Company or by any officer or officers of the Company authorized to make such determination, the authorization of the denomination of any Exchange Bond to be conclusively evidenced by the execution thereof on behalf of the Company. Exchange Bonds shall be numbered R-1 and consecutively upwards.

SECTION 6. TEMPORARY EXCHANGE BONDS. Until definitive Exchange Bonds are ready for delivery, there may be authenticated and issued in lieu of any thereof and subject to all of the provisions, limitations and conditions set forth in Section 3.11 of the Mortgage, temporary registered bonds without coupons.

SECTION 7. REDEMPTION OF EXCHANGE BONDS. (a) The Exchange Bonds shall be redeemable, at the option of the Company, as a whole or in part, at any time upon notice sent by the Company through the mail, postage prepaid, at least thirty (30) days and not more than forty-five (45) days prior to the date fixed for redemption, to the registered holder of each bond to be redeemed in whole or in part, addressed to such holder at his address appearing upon the registration books, at a redemption price equal to the greater of

(1) 100% of the principal amount of the Exchange Bonds to be redeemed, plus accrued interest to the redemption date, or

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(2) as determined by the Quotation Agent (as hereinafter defined), the sum of the present values of the remaining scheduled payments of principal and interest on the Exchange Bonds to be redeemed (not including any portion of payments of interest accrued as of the redemption date) discounted to the redemption date on a semi-annual basis (assuming a 360-day year consisting of twelve 30-day months) at the Adjusted Treasury Rate (as hereinafter defined) plus twenty-five
(25) basis points, plus accrued interest to the redemption date.

Unless the Company defaults in payment of the redemption price, on and after the redemption date, interest will cease to accrue on the Exchange Bonds or portions of the Exchange Bonds called for redemption.

For purposes of the foregoing, the following terms shall have the respective meanings set forth below:

"ADJUSTED TREASURY RATE" means, with respect to any redemption date, the rate per year equal to the semi-annual equivalent yield to maturity of the Comparable Treasury Issue, assuming a price for the Comparable Treasury Issue (expressed as a percentage of its principal amount) equal to the Comparable Treasury Price for the redemption date.

"BUSINESS DAY" means any day that is not a day on which banking institutions in New York City are authorized or required by law or regulation to close.

"COMPARABLE TREASURY ISSUE" means the United States Treasury security selected by the Quotation Agent as having a maturity comparable to the remaining term of the Exchange Bonds that would be used, at the time of selection and in accordance with customary financial practice, in pricing new issues of corporate debt securities of comparable maturity to the remaining term of the Exchange Bonds.

"COMPARABLE TREASURY PRICE" means, with respect to any redemption date:

(i) the average of the Reference Treasury Dealer Quotations for that redemption date, after excluding the highest and lowest of the Reference Treasury Dealer Quotations; or

(ii) if the Trustee obtains fewer than three Reference Treasury Dealer Quotations, the average of all Reference Treasury Dealer Quotations so received.

"QUOTATION AGENT" means the Reference Treasury Dealer appointed by the Company.

"REFERENCE TREASURY DEALER" means (1) each of J.P. Morgan Securities Inc. and Salomon Smith Barney Inc. and their respective successors, unless any of them ceases to be a primary U.S. Government securities dealer in New York City (a "PRIMARY TREASURY

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DEALER"), in which case the Company shall substitute another Primary Treasury Dealer; and (2) any other Primary Treasury Dealer selected by the Company.

"REFERENCE TREASURY DEALER QUOTATIONS" means, with respect to each Reference Treasury Dealer and any redemption date, the average, as determined by the Trustee, of the bid and asked prices for the Comparable Treasury Issue (expressed in each case as a percentage of its principal amount) quoted in writing to the Trustee by that Reference Treasury Dealer at 5:00 p.m., New York City time, on the third Business Day preceding that redemption date.

(b) In case the Company shall desire to exercise such right to redeem and pay off all or any part of such Exchange Bonds as hereinbefore provided, it shall comply with all the terms and provisions of Article V of the Mortgage applicable thereto, and such redemption shall be made under and subject to the terms and provisions of Article V and in the manner and with the effect therein provided, but at the time or times and upon mailing of notice, all as hereinbefore set forth in this Section 7. No publication of notice of any redemption of any Exchange Bonds shall be required under Section 5.03(a) of the Mortgage.

SECTION 8. BOOK-ENTRY ONLY SYSTEM. It is intended that the Exchange Bonds be registered so as to participate in the securities depository system (the "DTC SYSTEM") with The Depository Trust Company ("DTC"), as set forth herein. The Exchange Bonds shall be initially issued in the form of a fully registered bond or bonds in the name of Cede & Co., or any successor thereto, as nominee for DTC. The Company and the Trustees are authorized to execute and deliver such letters to or agreements with DTC as shall be necessary to effectuate the DTC System, including the Letter of Representations from the Company and the Trustees to DTC relating to the Exchange Bonds (the "REPRESENTATION LETTER"). In the event of any conflict between the terms of the Representation Letter and the Mortgage, the terms of the Mortgage shall control. DTC may exercise the rights of a bondholder only in accordance with the terms hereof applicable to the exercise of such rights.

With respect to Exchange Bonds registered in the name of DTC or its nominee, the Company and the Trustees shall have no responsibility or obligation to any broker-dealer, bank or other financial institution for which DTC holds such bonds from time to time as securities depository (each such broker-dealer, bank or other financial institution being referred to herein as a "DEPOSITORY PARTICIPANT") or to any person on behalf of whom such a Depository Participant holds an interest in such bonds (each such person being herein referred to as an "INDIRECT PARTICIPANT"). Without limiting the immediately preceding sentence, the Company and the Trustees shall have no responsibility or obligation with respect to:

(i) the accuracy of the records of DTC, its nominee or any Depository Participant with respect to any ownership interest in the Exchange Bonds,

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(ii) the delivery to any Depository Participant or any Indirect Participant or any other person, other than a registered owner of an Exchange Bond, of any notice with respect to the Exchange Bonds, including any notice of redemption,

(iii) the payment to any Depository Participant or Indirect Participant or any other person, other than a registered owner of an Exchange Bond, of any amount with respect to principal of, redemption premium, if any, on, or interest on, the Exchange Bonds, or

(iv) any consent given by DTC as registered owner.

So long as certificates for the Exchange Bonds are not issued as hereinafter provided, the Company and the Trustees may treat DTC or any successor securities depository as, and deem DTC or any successor securities depository to be, the absolute owner of such bonds for all purposes whatsoever, including, without limitation, (1) the payment of principal and interest on such bonds, (2) giving notice of matters (including redemption) with respect to such bonds and (3) registering transfers with respect to such bonds. While an Exchange Bond is in the DTC System, no person other than DTC or its nominee shall receive a certificate with respect to such bond.

In the event that:

(a) DTC notifies the Company that it is unwilling or unable to continue as depositary or if DTC ceases to be a clearing agency registered under applicable law and a successor depositary is not appointed by the Company within 90 days,

(b) the Company determines that the beneficial owners of the Exchange Bonds should be able to obtain certificated bonds and so notifies the Trustees in writing or

(c) there shall have occurred and be continuing a completed default or any event which after notice or lapse of time or both would be a completed default with respect to the Exchange Bonds,

the Exchange Bonds shall no longer be restricted to being registered in the name of DTC or its nominee. In the case of clause (a) of the preceding sentence, the Company may determine that the Exchange Bonds shall be registered in the name of and deposited with a successor depository operating a securities depository system, as may be acceptable to the Company and the Trustees, or such depository's agent or designee, and if the Company does not appoint a successor securities depository system within 90 days, then the bonds may be registered in whatever name or names registered owners of bonds transferring or exchanging such bonds shall designate, in accordance with the provisions hereof.

Notwithstanding any other provision of the Mortgage to the contrary, so long as any Exchange Bond is registered in the name of DTC or its nominee, all payments with respect to

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principal of and interest on such bond and all notices with respect to such bond shall be made and given, respectively, in the manner provided in the Representation Letter.

SECTION 9. LEGENDS. So long as the Exchange Bonds are held by the Depository Trust Company, such Exchange Bonds shall bear the following legend:

Unless this bond is presented by an authorized representative of the Depository Trust Company, a New York corporation ("DTC"), to the Company or its agent for registration of transfer, exchange or payment, and any bond issued is registered in the name of Cede & Co. or in such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), any transfer, pledge or other use hereof for value or otherwise by a person is wrongful inasmuch as the registered owner hereof, Cede & Co., has an interest herein.

SECTION 10. CONFIRMATION OF LIEN. The Company, for the equal and proportionate benefit and security of the holders of all bonds at any time issued under the Mortgage, hereby confirms the lien of the Mortgage upon, and hereby grants, bargains, sells, transfers, assigns, pledges, mortgages, warrants and conveys unto the Trustees, all property of the Company and all property hereafter acquired by the Company, other than (in each case) property which, by virtue of any of the provisions of the Mortgage, is excluded from such lien, and hereby confirms the title of the Trustees (as set forth in the Mortgage) in and to all such property. Without in any way limiting or restricting the generality of the foregoing, there is specifically included within the confirmation of lien and title hereinabove expressed the property of the Company legally described on EXHIBIT A attached hereto and made a part hereof.

SECTION 11. MISCELLANEOUS. The terms and conditions of this Supplemental Indenture shall be deemed to be a part of the terms and conditions of the Mortgage for any and all purposes. The Mortgage, as supplemented by said indentures supplemental thereto dated subsequent to August 1, 1944 and referred to in the recitals of this Supplemental Indenture, and as further supplemented by this Supplemental Indenture, is in all respects hereby ratified and confirmed.

This Supplemental Indenture shall bind and, subject to the provisions of Article XIV of the Mortgage, inure to the benefit of the respective successors and assigns of the parties hereto.

Although this Supplemental Indenture is dated as of ___________, 2002, it shall be effective only from and after the actual time of its execution and delivery by the Company and the Trustees on the date indicated by their respective acknowledgments hereto annexed.

This Supplemental Indenture may be simultaneously executed in any number of counterparts, and all such counterparts executed and delivered, each as an original, shall constitute but one and the same instrument.

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IN WITNESS WHEREOF, Commonwealth Edison Company has caused this Supplemental Indenture to be executed in its name by its Vice President and Treasurer, and attested by one of its Assistant Secretaries, and BNY Midwest Trust Company, as Trustee under the Mortgage, has caused this Supplemental Indenture to be executed in its name by one of its Vice Presidents, and attested by one of its Assistant Secretaries, and D. G. Donovan, as Co-Trustee under the Mortgage, has hereunto affixed his signature, all as of the day and year first above written.

COMMONWEALTH EDISON COMPANY

By
J. Barry Mitchell
VICE PRESIDENT AND TREASURER

ATTEST:

Scott N. Peters
ASSISTANT SECRETARY

BNY MIDWEST TRUST COMPANY

By
J. Bartolini
VICE PRESIDENT

ATTEST:

C. Potter
ASSISTANT SECRETARY

D. G. DONOVAN

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STATE OF ILLINOIS )

) SS.

COUNTY OF COOK )

I, _____________________, a Notary Public in and for said County, in the State aforesaid, DO HEREBY CERTIFY that J. BARRY MITCHELL, Vice President and Treasurer of Commonwealth Edison Company, an Illinois corporation, one of the parties described in and which executed the foregoing instrument, and SCOTT N. PETERS, an Assistant Secretary of said corporation, who are both personally known to me to be the same persons whose names are subscribed to the foregoing instrument as such Vice President and Treasurer and Assistant Secretary, respectively, and who are both personally known to me to be Vice President and Treasurer and an Assistant Secretary, respectively, of said corporation, appeared before me this day in person and severally acknowledged that they signed, executed and delivered said instrument as their free and voluntary act as such Vice President and Treasurer and Assistant Secretary, respectively, of said corporation, and as the free and voluntary act of said corporation, for the uses and purposes therein set forth.

GIVEN under my hand and notarial seal this __ day of _________, A.D. 2002.

NOTARY PUBLIC

(NOTARIAL SEAL)

My Commission expires ______________________.

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STATE OF ILLINOIS )

) SS.

COUNTY OF COOK )

I, _________________, a Notary Public in and for said County, in the State aforesaid, DO HEREBY CERTIFY that J. BARTOLINI, a Vice President of BNY Midwest Trust Company, an Illinois trust company, one of the parties described in and which executed the foregoing instrument, and C. POTTER, an Assistant Secretary of said trust company, who are both personally known to me to be the same persons whose names are subscribed to the foregoing instrument as such Vice President and Assistant Secretary, respectively, and who are both personally known to me to be a Vice President and an Assistant Secretary, respectively, of said trust company, appeared before me this day in person and severally acknowledged that they signed, executed and delivered said instrument as their free and voluntary act as such Vice President and Assistant Secretary, respectively, of said trust company, and as the free and voluntary act of said trust company, for the uses and purposes therein set forth.

GIVEN under my hand and notarial seal this ___ day of ______, A.D. 2002.

NOTARY PUBLIC

(NOTARIAL SEAL)

My Commission expires _______________.

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STATE OF ILLINOIS )

) SS.

COUNTY OF COOK )

I, _____________________, a Notary Public in and for said County, in the State aforesaid, DO HEREBY CERTIFY that D. G. DONOVAN, one of the parties described in and which executed the foregoing instrument, who is personally known to me to be the same person whose name is subscribed to the foregoing instrument, appeared before me this day in person and acknowledged that he signed, executed and delivered said instrument as his free and voluntary act for the uses and purposes therein set forth.

GIVEN under my hand and notarial seal this ___ day of _____, A.D. 2002.

NOTARY PUBLIC

(NOTARIAL SEAL)

My Commission expires ____________________.

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EXHIBIT A

LEGAL DESCRIPTIONS

See attached.

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EXHIBIT 4.2

COMMONWEALTH EDISON COMPANY

$400,000,000

First Mortgage 6.15% Bonds, Series 98 Due 2012

PURCHASE AGREEMENT

New York, New York
March 6, 2002

Salomon Smith Barney Inc.
J.P. Morgan Securities Inc.
As Representatives of the Initial Purchasers c/o Salomon Smith Barney Inc.
388 Greenwich Street
New York, New York 10013

Ladies and Gentlemen:

Commonwealth Edison Company, a corporation organized under the laws of the State of Illinois (the "Company"), proposes to issue and sell to the several parties named in Schedule I hereto (the "Initial Purchasers"), for whom you (the "Representatives") are acting as representatives, $400,000,000 principal amount of the Company's First Mortgage 6.15% Bonds, Series 98 Due 2012 (the "Securities"). The Securities are to be issued under the Company's Mortgage, dated as of July 1, 1923, as amended and supplemented through the date hereof, and as further supplemented by the Supplemental Indenture dated as of March 1, 2002 (the "Supplement") from the Company to BNY Midwest Trust Company, as trustee (the "Trustee") and D.G. Donovan as co-trustee (the "Co-Trustee"). As used herein, the term "Mortgage" refers to the Company's Mortgage referred to above together with any and all amendments or supplements thereto, including the Supplement. The Securities will have the benefit of a Registration Rights Agreement, dated as of the Closing Date (the "Registration Rights Agreement"), between the Company and the Initial Purchasers, pursuant to which the Company has agreed to register the Securities under the Act subject to the terms and conditions therein specified. Certain terms used herein are defined in Section 17 hereof.

The sale of the Securities to the Initial Purchasers will be made without registration of the Securities under the Act in reliance upon an exemption from the registration requirements of the Act.

In connection with the sale of the Securities, the Company has prepared a preliminary offering memorandum, dated March 6, 2002 (as amended or supplemented at the Execution Time, including any information incorporated by reference therein, the "Preliminary Memorandum"), and a final offering memorandum, dated March 6, 2002 (as amended or supplemented at the Execution Time, including any information incorporated by reference therein as of its date, the "Final Memorandum"). Each of the Preliminary Memorandum and the Final Memorandum sets forth certain information concerning the Company and the Securities. The Company hereby confirms that it has authorized the use of the Preliminary Memorandum

and the Final Memorandum, and any amendment or supplement thereto, in connection with the offer and sale of the Securities by the Initial Purchasers.

1. REPRESENTATIONS AND WARRANTIES. The Company represents and warrants to each Initial Purchaser as set forth below in this Section 1.

(a) The Preliminary Memorandum, at the date thereof, did not contain any untrue statement of a material fact or omit to state any material fact necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading. At the Execution Time and on the Closing Date, the Final Memorandum did not, and will not (and any amendment or supplement thereto, at the date thereof and at the Closing Date, will not), contain any untrue statement of a material fact or omit to state any material fact necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading; PROVIDED, HOWEVER, that the Company makes no representation or warranty as to the information contained in or omitted from the Preliminary Memorandum or the Final Memorandum, or any amendment or supplement thereto, in reliance upon and in conformity with information furnished in writing to the Company by or on behalf of the Initial Purchasers through the Representatives specifically for inclusion therein.

(b) Neither the Company, nor any of its Affiliates, nor any person acting on its or their behalf (it being understood that the Company makes no representation or warranty with respect to the Representatives or any Initial Purchaser) has, directly or indirectly, made offers or sales of any security, or solicited offers to buy any security, under circumstances that would require the registration of the Securities under the Act.

(c) Neither the Company, nor any of its Affiliates, nor any person acting on its or their behalf (it being understood that the Company makes no representation or warranty with respect to the Representatives or any Initial Purchaser) has engaged in any form of general solicitation or general advertising (within the meaning of Regulation D) in connection with any offer or sale of the Securities in the United States.

(d) The Securities satisfy the eligibility requirements of Rule 144A(d)(3) under the Act.

(e) The Company has not paid or agreed to pay to any person any compensation for soliciting another to purchase any Securities of the Company (except as contemplated by this Agreement).

(f) The Company has not taken, directly or indirectly, any action designed to cause or which has constituted or which might reasonably be expected to cause or result, under the Exchange Act or otherwise, in the stabilization or manipulation of the price of any security of the Company to facilitate the sale or resale of the Securities.

(g) The statements in the Final Memorandum under the headings "Description of Bonds" and "Exchange Offer; Registration Rights" fairly summarize the matters therein described.

(h) This Agreement has been duly authorized, executed and delivered by the Company; the Mortgage has been duly authorized and, assuming due authorization, execution and delivery of the Supplement by the Trustee and due execution and delivery of the Supplement by the Co-Trustee, when executed and delivered by the Company, will constitute a legal, valid, binding instrument enforceable against the Company in accordance with its terms (subject, as to the enforcement of remedies, to applicable bankruptcy, reorganization, insolvency, moratorium or other laws affecting creditors' rights generally from time to time in effect and to general principles of equity); the Securities have been duly authorized, and, when executed and authenticated in accordance with the provisions of the Mortgage and delivered to and paid for by the Initial Purchasers, will have been duly executed and delivered by the Company and will constitute the legal, valid and binding obligations of the Company entitled to the benefits of the Mortgage (subject, as to the enforcement of remedies, to applicable bankruptcy, insolvency, moratorium or other laws affecting creditors' rights generally from time to time in effect and to general principles of equity); and the Registration Rights Agreement has been duly authorized and, when executed and delivered by the Company, will constitute the legal, valid, binding and enforceable instrument of the Company (subject, as to the enforcement of remedies, to applicable bankruptcy, reorganization, insolvency, moratorium or other laws affecting creditors' rights generally from time to time in effect and to general principles of equity).

(i) The Company has filed with the Illinois Commerce Commission a petition with respect to the issuance and sale of the Securities and said Commission has issued its order authorizing and approving such issuance and sale. No consent of or approval by any other public board or body or administrative agency, federal or state, is necessary in connection with the transactions contemplated by this Agreement, the Mortgage or the Registration Rights Agreement, except as may be required under the blue sky laws of any jurisdiction in connection with the purchase and distribution of the Securities by the Initial Purchasers in the manner contemplated herein and in the Final Memorandum and as may be required under the Act in connection with the transactions contemplated by the Registration Rights Agreement.

(j) Neither the Company nor any significant subsidiary, as defined in Rule 1-02 of Regulation S-X of the Securities and Exchange Commission ("significant subsidiary") is in violation of its articles of incorporation, or in default in the performance or observance of any material obligation, agreement, covenant or condition contained in any mortgage or any material contract, lease, note or other instrument to which it is a party or by which it may be bound, or materially in violation of any law, administrative regulation or administrative, arbitration or court order to which it is subject or bound, except in each case to such extent as may be set forth in the Final Memorandum; and the execution and delivery of this Agreement, the incurrence of the obligations herein set forth and the consummation of the transactions herein contemplated will not conflict with or constitute a breach of, or default under, the articles of incorporation or by-laws of the Company or any mortgage, contract, lease, note or other instrument to which the Company or any significant subsidiary is a party or by which it or any significant subsidiary may be bound, or any law, administrative regulation or administrative, arbitration or court order to which it is subject or bound.

(k) The Company has good and sufficient title to all property described or referred to in the Mortgage and purported to be conveyed thereby, subject only to the lien of the Mortgage and permitted liens as therein defined (except as to property released from the lien of

the Mortgage in connection with the sale or other disposition thereof, and certain other exceptions which are not material in the aggregate). The Mortgage has been duly filed for recordation in such manner and in such places as is required by law in order to give constructive notice of, establish, preserve and protect the lien of the Mortgage. The Mortgage constitutes a valid, direct first mortgage lien on substantially all property (including franchises) now owned by the Company, except property expressly excepted by the terms of the Mortgage, subject to permitted liens as defined therein. The Mortgage will constitute a valid, direct first mortgage lien on all property of the character of that now subject to the lien of the Mortgage hereafter acquired by the Company, subject to permitted liens as defined in the Mortgage, and to liens, if any, existing or placed on such after-acquired property at the time of the acquisition thereof.

(l) The financial statements included or incorporated by reference in the Final Memorandum present fairly in all material respects the financial position, results of operations and cash flows of the Company at the respective dates and for the respective periods specified and, except as otherwise stated in the Final Memorandum, said financial statements have been prepared in conformity with generally accepted accounting principles applied on a consistent basis during the periods involved. The Company has no material contingent obligation which is not disclosed in the Final Memorandum.

(m) Except as set forth in or contemplated by the Final Memorandum, no material transaction has been entered into by the Company otherwise than in the ordinary course of business and no materially adverse change has occurred in the condition, financial or otherwise, of the Company, in each case since the respective dates as of which information is given in the Final Memorandum.

(n) The Company has been duly incorporated and is validly existing as a corporation in good standing under the laws of the State of Illinois with corporate power and authority to own its properties and conduct its business as described in the Final Memorandum.

(o) Each significant subsidiary of the Company has been duly incorporated and is validly existing as a corporation in good standing under the laws of the jurisdiction of its incorporation; all of the issued and outstanding capital stock of each significant subsidiary has been duly and validly issued and is fully paid and nonassessable; and all of the capital stock of each significant subsidiary is owned by the Company free and clear of any pledge, lien, encumbrance, claim or equity.

(p) There is no pending or threatened suit or proceeding before any court or governmental agency, authority or body or any arbitration involving the Company or any of its significant subsidiaries required to be disclosed in the Final Memorandum which is not adequately disclosed in the Final Memorandum.

(q) The franchise granted to the Company by the City Council of the City of Chicago under an ordinance effective January 1, 1992, is valid and subsisting and duly authorizes the Company to engage in the electric utility business conducted by it in such City. The several franchises of the Company outside the City of Chicago are valid and subsisting and authorize the Company to carry on its utility business in the several communities, capable of granting franchises, located in the territory served by the Company outside the City of Chicago (with immaterial exceptions).

(r) PricewaterhouseCoopers LLP, the accountants who certified certain of the financial statements included or incorporated by reference in the Final Memorandum, are independent public accountants as required by the Act and the applicable published rules and regulations thereunder.

Any certificate signed by any officer of the Company and delivered to the Representatives or counsel for the Representatives in connection with the offering of the Securities shall be deemed a representation and warranty by the Company, as to matters covered thereby, to each Initial Purchaser.

2. PURCHASE AND SALE. Subject to the terms and conditions and in reliance upon the representations and warranties herein set forth, the Company agrees to sell to each Initial Purchaser, and each Initial Purchaser agrees, severally and not jointly, to purchase from the Company, at a purchase price of 99.261% of the principal amount thereof, plus accrued interest, if any, from March 13, 2002 to the Closing Date, the principal amount of Securities set forth opposite such Initial Purchaser's name in Schedule I hereto.

3. DELIVERY AND PAYMENT. Delivery of and payment for the Securities shall be made at 10:00 A.M., New York City time, on March 13, 2002, or at such time on such later date as the Representatives shall designate, which date and time may be postponed by agreement between the Representatives and the Company or as provided in Section 9 hereof (such date and time of delivery and payment for the Securities being herein called the "Closing Date"). Delivery of the Securities shall be made to the Representatives for the respective accounts of the several Initial Purchasers against payment by the several Initial Purchasers through the Representatives of the purchase price thereof to or upon the order of the Company by wire transfer payable in same-day funds to the account specified by the Company. Delivery of the Securities shall be made through the facilities of The Depository Trust Company.

4. OFFERING BY INITIAL PURCHASERS. Each Initial Purchaser, severally and not jointly, represents and warrants to and agrees with the Company, which agreement shall be confirmed by such Initial Purchaser's purchase of the Securities, that:

(a) It has not offered or sold, and will not offer or sell, any Securities except to those persons it reasonably believes to be qualified institutional buyers (as defined in Rule 144A under the Act) and that, in connection with each such sale, it has taken or will take reasonable steps to ensure that the purchaser of such Securities is aware that such sale is being made in reliance on Rule 144A.

(b) Neither it nor any person acting on its behalf has made or will make offers or sales of the Securities by means of any form of general solicitation or general advertising (within the meaning of Regulation D) in the United States.

5. AGREEMENTS. The Company agrees with each Initial Purchaser that:

(a) The Company will furnish to each Initial Purchaser, without charge, during the period referred to in paragraph (c) below, as many copies of the Final Memorandum and any amendments and supplements thereto as it may reasonably request.

(b) The Company will advise each Initial Purchaser promptly of any proposal to amend or supplement the Final Memorandum and will not effect such amendment or supplement without the consent of the Initial Purchasers, which consent shall not be unreasonably withheld. Neither the consent of the Initial Purchasers, nor the Initial Purchasers' delivery of any such amendment or supplement, shall constitute a waiver of any of the conditions set forth in
Section 6.

(c) If at any time prior to the completion of the sale of the Securities by the Initial Purchasers (as determined by the Representatives), any event occurs as a result of which the Final Memorandum, as then amended or supplemented, would include any untrue statement of a material fact or omit to state any material fact necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading, or if it should be necessary to amend or supplement the Final Memorandum to comply with applicable law, the Company promptly (i) will notify the Representatives of any such event; (ii) subject to the requirements of paragraph (b) of this Section 5, will prepare an amendment or supplement that will correct such statement or omission or effect such compliance; and (iii) will supply any supplemented or amended Final Memorandum to the several Initial Purchasers without charge in such quantities as you may reasonably request.

(d) The Company will arrange, if necessary, for the qualification of the Securities for sale by the Initial Purchasers under the laws of such jurisdictions as the Initial Purchasers may designate and will maintain such qualifications in effect so long as required for the sale of the Securities; PROVIDED that in no event shall the Company be obligated to qualify to do business in any jurisdiction where it is not now so qualified or to take any action that would subject it to service of process in suits (other than those arising out of the offering or sale of the Securities) in any jurisdiction where it is not now so subject. The Company will promptly advise the Representatives of the receipt by the Company of any notification with respect to the suspension of the qualification of the Securities for sale in any jurisdiction or the initiation or threatening of any proceeding for such purpose.

(e) From the date hereof through the third anniversary of the Closing Date, the Company will not, and will not permit any of its Affiliates to, resell any Securities that have been acquired by any of them.

(f) None of the Company, any of its Affiliates, or any person acting on its or their behalf will, directly or indirectly, make offers or sales of any security, or solicit offers to buy any security, under circumstances that would require the registration of the Securities under the Act.

(g) None of the Company, any of its Affiliates, or any person acting on its or their behalf will engage in any form of general solicitation or general advertising (within the meaning of Regulation D) in connection with any offer or sale of the Securities in the United States.

(h) So long as any of the Securities are "restricted securities" within the meaning of Rule 144(a)(3) under the Act, the Company will, during any period in which it is not subject to and in compliance with Section 13 or 15(d) of the Exchange Act or it is not exempt from such reporting requirements pursuant to and in compliance with Rule 12g3-2(b) under the

Exchange Act, provide to each holder of such restricted securities and to each prospective purchaser (as designated by such holder) of such restricted securities, upon the request of such holder or prospective purchaser, any information required to be provided by Rule 144A(d)(4) under the Act. This covenant is intended to be for the benefit of the holders, and the prospective purchasers designated by such holders, from time to time of such restricted securities.

(i) None of the Company, any of its Affiliates or any person acting on its or their behalf will engage in any directed selling efforts with respect to the Securities.

(j) The Company will cooperate with the Representatives and use its best efforts to permit the Securities to be eligible for clearance and settlement through The Depository Trust Company.

(k) The Company will not for a period of 14 days following the Execution Time, without the prior written consent of Salomon Smith Barney Inc., offer, sell or contract to sell, or otherwise dispose of (or enter into any transaction which is designed to, or might reasonably be expected to, result in the disposition (whether by actual disposition or effective economic disposition due to cash settlement or otherwise) by the Company, directly or indirectly, or announce the offering of, any long-term debt securities issued or guaranteed by the Company (other than the Securities) provided, however, that the foregoing shall not be deemed to prevent the Company from entering into a loan agreement with the Illinois Development Finance Authority ("IDFA"), and issuing a first mortgage bond as collateral security for its obligations under such loan agreement, in connection with the contemplated offering and sale of $100,000,000 aggregate principal amount of Pollution Control Revenue Refunding Bonds (Commonwealth Edison Company Project) Series 2002 due April 15, 2013.

(l) The Company will not take, directly or indirectly, any action designed to or which has constituted or which might reasonably be expected to cause or result, under the Exchange Act or otherwise, in stabilization or manipulation of the price of any security of the Company to facilitate the sale or resale of the Securities.

(m) The Company agrees to pay the costs and expenses relating to the following matters: (i) the preparation of the Supplement and the Registration Rights Agreement, the issuance of the Securities and the fees of the Trustee;
(ii) the preparation, printing or reproduction of the Preliminary Memorandum and Final Memorandum and each amendment or supplement to either of them; (iii) the printing (or reproduction) and delivery (including postage, air freight charges and charges for counting and packaging) of such copies of the Final Memorandum, and all amendments or supplements to it, as may, be reasonably requested for use in connection with the offering and sale of the Securities; (iv) the preparation, printing, authentication, issuance and delivery of certificates for the Securities, including any stamp or transfer taxes in connection with the original issuance and sale of the Securities; (v) the printing (or reproduction) and delivery of this Agreement, any blue sky memorandum and all other agreements or documents printed (or reproduced) and delivered in connection with the offering of the Securities; (vi) any registration or qualification of the Securities for offer and sale under the securities or blue sky laws of the several states (including filing fees and the reasonable fees and expenses of counsel for the Initial Purchasers relating to such registration and qualification); (vii) the transportation and other expenses incurred by or on behalf of Company representatives in connection with presentations to prospective purchasers of the Securities; (viii) the fees and

expenses of the Company's accountants and counsel (including local and special counsel); (ix) the fees and expenses of any rating agencies rating the Securities and (x) all other costs and expenses incident to the performance by the Company of its obligations hereunder.

6. CONDITIONS TO THE OBLIGATIONS OF THE INITIAL PURCHASERS. The obligations of the Initial Purchasers to purchase the Securities shall be subject to the accuracy of the representations and warranties on the part of the Company contained herein at the Execution Time and the Closing Date, to the accuracy of the statements of the Company made in any certificates pursuant to the provisions hereof, to the performance by the Company of its obligations hereunder and to the following additional conditions:

(a) Sidley Austin Brown & Wood, counsel for the Company, shall have furnished to the Representatives its opinion, dated the Closing Date and addressed to the Representatives, in form and substance satisfactory to each of the Representatives and its counsel.

(b) The Representatives shall have received from Winston & Strawn, counsel for the Initial Purchasers, such opinion or opinions, dated the Closing Date and addressed to the Representatives, with respect to the issuance and sale of the Securities, the Mortgage, the Registration Rights Agreement, the Final Memorandum (as amended or supplemented at the Closing Date) and other related matters as the Representatives may reasonably require, and the Company shall have furnished to such counsel such documents as they request for the purpose of enabling them to pass upon such matters.

(c) The Company shall have furnished to the Representatives a certificate of the Company, signed by the Treasurer of the Company, dated the Closing Date, to the effect that the signer of such certificate has carefully examined the Final Memorandum, any amendment or supplement to the Final Memorandum and this Agreement and that:

(i) the representations and warranties of the Company in this Agreement are true and correct in all material respects on and as of the Closing Date with the same effect as if made on the Closing Date, and the Company has complied with all the agreements and satisfied all the conditions on its part to be performed or satisfied hereunder at or prior to the Closing Date; and

(ii) since the date of the most recent financial statements included in the Final Memorandum (exclusive of any amendment or supplement thereto), there has been no material adverse change in the financial condition, business or properties of the Company and its subsidiaries, taken as a whole, whether or not arising from transactions in the ordinary course of business, except as set forth in or contemplated by the Final Memorandum (exclusive of any amendment or supplement thereto).

(d) At the Execution Time and at the Closing Date, the Company shall have requested and caused PricewaterhouseCoopers LLP to furnish to the Representatives letters, dated respectively as of the Execution Time and as of the Closing Date, in form and substance satisfactory to the Representatives.

(e) Subsequent to the Execution Time or, if earlier, the dates as of which information is given in the Final Memorandum (exclusive of any amendment or supplement thereto), there shall not have been (i) any change or decrease specified in the letter or letters referred to in paragraph (d) of this Section 6; or (ii) any change, or any development involving a prospective change, in or affecting the financial condition, business or properties of the Company and its subsidiaries, taken as a whole, whether or not arising from transactions in the ordinary course of business, except as set forth in or contemplated in the Final Memorandum (exclusive of any amendment or supplement thereto) the effect of which, in any case referred to in clause (i) or (ii) above, is, in the sole judgment of the Representatives, so material and adverse as to make it impractical or inadvisable to market the Securities as contemplated by the Final Memorandum (exclusive of any amendment or supplement thereto).

(f) On the Closing Date, (i) the Securities shall be rated "A3" by Moody's Investors Service, Inc. and "A-" by Standard & Poor's Rating Services, and the Company shall have delivered to the Representatives evidence satisfactory to the Representatives confirming that the Securities have such ratings, and (ii) since the Execution Time, there shall not have occurred a downgrading in the rating assigned to the Securities or any of the Company's first mortgage bonds or commercial paper by any "nationally recognized statistical rating agency", as that term is defined by the Commission for purposes of Rule 436(g)(2) under the Act, and no such securities rating agency shall have publicly announced that it has under surveillance or review, with possible negative implications, its rating of the Securities or any of the Company's other debt securities.

(g) On the Closing Date, the Initial Purchasers shall have received the Registration Rights Agreement duly executed and delivered by the Company and such agreement shall be in full force and effect according to its terms at all times from and after the Closing Date.

(h) Prior to the Closing Date, the Company shall have furnished to the Representatives such further information, certificates and documents as the Representatives may reasonably request.

(i) If any of the conditions specified in this Section 6 shall not have been fulfilled in all material respects when and as provided in this Agreement, or if any of the opinions and certificates mentioned above or elsewhere in this Agreement shall not be in all material respects reasonably satisfactory in form and substance to the Representatives and counsel for the Initial Purchasers, this Agreement and all obligations of the Initial Purchasers hereunder may be cancelled at, or at any time prior to, the Closing Date by the Representatives. Notice of such cancellation shall be given to the Company in writing or by telephone or facsimile confirmed in writing.

The documents required to be delivered by this Section 6 will be delivered at the office of counsel for the Company, at Sidley Austin Brown & Wood, 10 South Dearborn Street, Suite 5500, Chicago, Illinois 60603, on the Closing Date.

7. REIMBURSEMENT OF EXPENSES. If the sale of the Securities provided for herein is not consummated because any condition to the obligations of the Initial Purchasers set forth in Section 6 hereof is not satisfied, because of any termination pursuant to Section 10 hereof or because of any refusal, inability or failure on the part of the Company to perform any agreement

herein or comply with any provision hereof other than by reason of a default by any of the Initial Purchasers, the Company will reimburse the Initial Purchasers severally through Salomon Smith Barney Inc. on demand for all out-of-pocket expenses (including reasonable fees and disbursements of counsel) that shall have been incurred by them in connection with the proposed purchase and sale of the Securities.

8. INDEMNIFICATION AND CONTRIBUTION. (a) The Company agrees to indemnify and hold harmless each Initial Purchaser, the directors, officers, employees and agents of each Initial Purchaser and each person who controls any Initial Purchaser within the meaning of either the Act or the Exchange Act against any and all losses, claims, damages or liabilities, joint or several, to which they or any of them may become subject under the Act, the Exchange Act or other Federal or state statutory law or regulation, at common law or otherwise, insofar as such losses, claims, damages or liabilities (or actions in respect thereof) arise out of or are based upon any untrue statement or alleged untrue statement of a material fact contained in the Preliminary Memorandum, the Final Memorandum (or in any supplement or amendment thereto) or any information provided by the Company to any holder or prospective purchaser of Securities pursuant to Section 5(h), or in any amendment thereof or supplement thereto, or arise out of or are based upon the omission or alleged omission to state therein a material fact required to be stated therein or necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading, and agrees to reimburse each such indemnified party, as incurred, for any legal or other expenses reasonably incurred by them in connection with investigating or defending any such loss, claim, damage, liability or action; PROVIDED, HOWEVER, that the Company will not be liable in any such case to the extent that any such loss, claim, damage or liability arises out of or is based upon any such untrue statement or alleged untrue statement or omission or alleged omission made in the Preliminary Memorandum or the Final Memorandum, or in any amendment thereof or supplement thereto, in reliance upon and in conformity with written information furnished to the Company by or on behalf of any Initial Purchasers through the Representatives specifically for inclusion therein; PROVIDED, FURTHER, that the foregoing indemnity with respect to any untrue statement contained in or omission from the Preliminary Memorandum shall not inure to the benefit of any Initial Purchaser (or any of the directors, officers, employees and agents of such Initial Purchaser or any person controlling such Initial Purchaser) from whom the person asserting any such loss, claim, damage or liability purchased the Securities which are the subject thereof if such person did not receive a copy of the Final Memorandum (or the Final Memorandum as then amended or supplemented if the Company shall have furnished any amendments or supplements thereto) at or prior to the confirmation of the sale of such Securities to such person in any case where such delivery is required by the Act and the untrue statement or omission of a material fact contained in such Preliminary Memorandum was corrected in the Final Memorandum (or the Final Memorandum as so amended or supplemented if the Company shall have furnished any amendments or supplements thereto), and it is finally judicially determined that such delivery was required to be made under the Act and was not so made. This indemnity agreement will be in addition to any liability which the Company may otherwise have.

(b) Each Initial Purchaser severally and not jointly agrees to indemnify and hold harmless the Company, and each of its directors, officers, employees and agents, and each person who controls the Company within the meaning of either the Act or the Exchange Act, to the same extent as the foregoing indemnity from the Company to each Initial Purchaser, but only

with reference to written information relating to such Initial Purchaser furnished to the Company by or on behalf of such Initial Purchaser through the Representatives specifically for inclusion in the Preliminary Memorandum or the Final Memorandum (or in any amendment or supplement thereto). This indemnity agreement will be in addition to any liability which any Initial Purchaser may otherwise have. The Company acknowledges that the statements set forth in the last paragraph of the cover page regarding the delivery of the Securities, and, under the heading "Plan of Distribution" in the Preliminary Memorandum and the Final Memorandum, (i) the fourth sentence of the fifth paragraph related to market-making activities; (ii) the sixth paragraph related to stabilization, syndicate covering transactions and penalty bids; (iii) the seventh paragraph related to Internet distributions; and (iv) the eighth paragraph related to affiliates of one of the Initial Purchasers, constitute the only information furnished in writing by or on behalf of the Initial Purchasers for inclusion in the Preliminary Memorandum or the Final Memorandum (or in any amendment or supplement thereto).

(c) Promptly after receipt by an indemnified party under this Section 8 of notice of the commencement of any action, such indemnified party will, if a claim in respect thereof is to be made against the indemnifying party under this
Section 8, notify the indemnifying party in writing of the commencement thereof; but the failure so to notify the indemnifying party (i) will not relieve it from liability under paragraph (a) or (b) above unless and to the extent it did not otherwise learn of such action and such failure results in the forfeiture by the indemnifying party of substantial rights and defenses; and (ii) will not, in any event, relieve the indemnifying party from any obligations to any indemnified party other than the indemnification obligation provided in paragraph (a) or (b) above. The indemnifying party shall be entitled to appoint counsel of the indemnifying party's choice at the indemnifying party's expense to represent the indemnified party in any action for which indemnification is sought (in which case the indemnifying party shall not thereafter be responsible for the fees and expenses of any separate counsel retained by the indemnified party or parties except as set forth below); PROVIDED, HOWEVER, that such counsel shall be satisfactory to the indemnified party. Notwithstanding the indemnifying party's election to appoint counsel to represent the indemnified party in an action, the indemnified party shall have the right to employ separate counsel (including local counsel), and the indemnifying party shall bear the reasonable fees, costs and expenses of such separate counsel if (i) the use of counsel chosen by the indemnifying party to represent the indemnified party would present such counsel with a conflict of interest; (ii) the actual or potential defendants in, or targets of, any such action include both the indemnified party and the indemnifying party and the indemnified party shall have reasonably concluded that there may be legal defenses available to it and/or other indemnified parties which are different from or additional to those available to the indemnifying party; (iii) the indemnifying party shall not have employed counsel satisfactory to the indemnified party to represent the indemnified party within a reasonable time after notice of the institution of such action; or (iv) the indemnifying party shall authorize the indemnified party to employ separate counsel at the expense of the indemnifying party. An indemnifying party will not, without the prior written consent of the indemnified parties, settle or compromise or consent to the entry of any judgment with respect to any pending or threatened claim, action, suit or proceeding in respect of which indemnification or contribution may be sought hereunder (whether or not the indemnified parties are actual or potential parties to such claim or action) unless such settlement, compromise or consent includes an unconditional release of each indemnified party from all liability arising out of such claim, action, suit or proceeding.

(d) In the event that the indemnity provided in paragraph (a) or (b) of this Section 8 is for any reason held to be unenforceable by an indemnified party although applicable in accordance with its terms, the Company and the Initial Purchasers agree to contribute to the aggregate losses, claims, damages and liabilities (including legal or other expenses reasonably incurred in connection with investigating or defending same) (collectively "Losses") to which the Company and one or more of the Initial Purchasers may be subject in such proportion as is appropriate to reflect the relative benefits received by the Company on the one hand and by the Initial Purchasers on the other from the offering of the Securities; PROVIDED, HOWEVER, that in no case shall any Initial Purchaser (except as may be provided in any agreement among the Initial Purchasers relating to the offering of the Securities) be responsible for any amount in excess of the purchase discount or commission applicable to the Securities purchased by such Initial Purchaser hereunder; PROVIDED, FURTHER, that each Initial Purchaser's obligation to contribute to Losses hereunder shall be several and not joint. If the allocation provided by the immediately preceding sentence is unavailable for any reason, the Company and the Initial Purchasers shall contribute in such proportion as is appropriate to reflect not only such relative benefits but also the relative fault of the Company on the one hand and of the Initial Purchasers on the other in connection with the statements or omissions which resulted in such Losses, as well as any other relevant equitable considerations. Benefits received by the Company shall be deemed to be equal to the total net proceeds from the offering (before deducting expenses) received by it, and benefits received by the Initial Purchasers shall be deemed to be equal to the total purchase discounts and commissions in each case set forth on the cover of the Final Memorandum. Relative fault shall be determined by reference to, among other things, whether any untrue or any alleged untrue statement of a material fact or the omission or alleged omission to state a material fact relates to information provided by the Company on the one hand or the Initial Purchasers on the other, the intent of the parties and their relative knowledge, information and opportunity to correct or prevent such untrue statement or omission. The Company and the Initial Purchasers agree that it would not be just and equitable if contribution were determined by pro rata allocation or any other method of allocation which does not take account of the equitable considerations referred to above. Notwithstanding the provisions of this paragraph (d), no person guilty of fraudulent misrepresentation (within the meaning of Section 11(f) of the Act) shall be entitled to contribution from any person who was not guilty of such fraudulent misrepresentation. For purposes of this Section 8, each person who controls an Initial Purchaser within the meaning of either the Act or the Exchange Act and each director, officer, employee and agent of an Initial Purchaser shall have the same rights to contribution as such Initial Purchaser, and each person who controls the Company within the meaning of either the Act or the Exchange Act and each officer, director, employee or agent of the Company shall have the same rights to contribution as the Company, subject in each case to the applicable terms and conditions of this paragraph (d).

9. DEFAULT BY AN INITIAL PURCHASER. If any one or more Initial Purchasers shall fail to purchase and pay for any of the Securities agreed to be purchased by such Initial Purchaser hereunder and such failure to purchase shall constitute a default in the performance of its or their obligations under this Agreement, the remaining Initial Purchasers shall be obligated severally to take up and pay for (in the respective proportions which the amount of Securities set forth opposite their names in Schedule I hereto bears to the aggregate amount of Securities set forth opposite the names of all the remaining Initial Purchasers) the Securities which the defaulting Initial Purchaser or Initial Purchasers agreed but failed to purchase; PROVIDED, HOWEVER, that in

the event that the aggregate amount of Securities which the defaulting Initial Purchaser or Initial Purchasers agreed but failed to purchase shall exceed 10% of the aggregate amount of Securities set forth in Schedule I hereto, the remaining Initial Purchasers shall have the right to purchase all, but shall not be under any obligation to purchase any, of the Securities, and if such nondefaulting Initial Purchasers do not purchase all the Securities, this Agreement will terminate without liability to any nondefaulting Initial Purchaser or the Company. In the event of a default by any Initial Purchaser as set forth in this Section 9, the Closing Date shall be postponed for such period, not exceeding five Business Days, as the Representatives shall determine in order that the required changes in the Final Memorandum or in any other documents or arrangements may be effected. Nothing contained in this Agreement shall relieve any defaulting Initial Purchaser of its liability, if any, to the Company or any nondefaulting Initial Purchaser for damages occasioned by its default hereunder.

10. TERMINATION. This Agreement shall be subject to termination in the absolute discretion of the Representatives, by notice given to the Company prior to delivery of and payment for the Securities, if at any time after the date hereof and prior to the delivery of and payment for the Securities (i) trading in Exelon Corporation's common stock shall have been suspended by the Commission or the New York Stock Exchange or trading in securities generally on the New York Stock Exchange shall have been suspended or limited or minimum prices shall have been established on such Exchange; (ii) a banking moratorium shall have been declared either by Federal or New York State authorities; or (iii) there shall have occurred any outbreak or escalation of hostilities, declaration by the United States of a national emergency or war or other calamity or crisis the effect of which on financial markets is such as to make it, in the sole judgment of the Representatives, impracticable or inadvisable to proceed with the offering or delivery of the Securities as contemplated by the Final Memorandum (exclusive of any amendment or supplement thereto).

11. INDEMNITIES TO SURVIVE. The respective agreements, representations, warranties, indemnities and other statements of the Company or its officers and of the Initial Purchasers set forth in or made pursuant to this Agreement will remain in full force and effect, regardless of any investigation made by or on behalf of the Initial Purchasers or the Company or any of the officers, directors or controlling persons referred to in Section 8 hereof, and will survive delivery of and payment for the Securities. The provisions of Sections 7 and 8 hereof shall survive the termination or cancellation of this Agreement.

12. NOTICES. All communications hereunder will be in writing and effective only on receipt, and, if sent to the Representatives, will be mailed, delivered or telefaxed to the Salomon Smith Barney General Counsel (fax no.:
(212) 816-7912) and confirmed to Salomon Smith Barney at 388 Greenwich Street, New York, New York 10013 Attention: General Counsel; or, if sent to the Company, will be mailed, delivered or telefaxed to Exelon Corporation, 10 South Dearborn Street, 37th Floor, P.O. Box 805379, Chicago, Illinois 60680-5379, Attention:
Vice President and Treasurer (fax no.: (312) 394-5440) and confirmed to the General Counsel of Exelon Corporation (fax no.: (312) 394-2900).

13. SUCCESSORS. This Agreement will inure to the benefit of and be binding upon the parties hereto and their respective successors and the officers and directors and controlling persons referred to in Section 8 hereof, and, except as expressly set forth in Section 5(h) hereof, no other person will have any right or obligation hereunder.

14. APPLICABLE LAW. This Agreement will be governed by and construed in accordance with the laws of the State of New York applicable to contracts made and to be performed within the State of New York.

15. COUNTERPARTS. This Agreement may be executed in one or more counterparts, each of which shall constitute an original and all of which together shall constitute one and the same instrument.

16. HEADINGS. The section headings used herein are for convenience only and shall not affect the construction hereof.

17. DEFINITIONS. The terms which follow, when used in this Agreement, shall have the meanings indicated.

"Act" shall mean the Securities Act of 1933, as amended, and the rules and regulations of the Commission promulgated thereunder.

"Affiliate" shall have the meaning specified in Rule 501(b) of Regulation D.

"Business Day" shall mean any day other than a Saturday, a Sunday or a legal holiday or a day on which banking institutions or trust companies are authorized or obligated by law to close in the City of New York.

"Commission" shall mean the Securities and Exchange Commission.

"Exchange Act" shall mean the Securities Exchange Act of 1934, as amended, and the rules and regulations of the Commission promulgated thereunder.

"Execution Time" shall mean the date and time that this Agreement is executed and delivered by the parties hereto.

"NASD" shall mean the National Association of Securities Dealers, Inc.

"Regulation D" shall mean Regulation D under the Act.

If the foregoing is in accordance with your understanding of our agreement, please sign and return to us the enclosed duplicate hereof, whereupon this Agreement and your acceptance shall represent a binding agreement between the Company and the several Initial Purchasers.

Very truly yours,

COMMONWEALTH EDISON COMPANY

By:

Name:
Title:

The foregoing Agreement is hereby
confirmed and accepted as of the
date first above written.

SALOMON SMITH BARNEY INC.
J.P. MORGAN SECURITIES INC.

By: SALOMON SMITH BARNEY INC.

By:
Name:
Title:

For themselves and the other several
Initial Purchasers named in
Schedule I to the foregoing
Agreement.

SCHEDULE I 

                                                                  Principal
                                                                  Amount of
                                                                  Securities
                                                                    to be
Initial Purchasers                                                Purchased
------------------                                                ---------
J.P. Morgan Securities Inc................................     $ 140,000,000
Salomon Smith Barney Inc..................................       140,000,000
ABN AMRO Incorporated.....................................        24,000,000
BNP Paribas Securities Corp. .............................        24,000,000
BNY Capital Markets, Inc. ................................        24,000,000
First Union Securities, Inc. .............................        24,000,000
Scotia Capital (USA) Inc. ................................        24,000,000
                                                               -------------
               Total......................................     $ 400,000,000

EXHIBIT 4.3

COMMONWEALTH EDISON COMPANY

$200,000,000

First Mortgage 6.15% Bonds, Series 98 Due 2012

PURCHASE AGREEMENT

New York, New York
June 13, 2002

Barclays Capital Inc.
First Union Securities, Inc.
As Representatives of the Initial Purchasers c/o Barclays Capital Inc.
222 Broadway
New York, New York 10038

Ladies and Gentlemen:

Commonwealth Edison Company, a corporation organized under the laws of the State of Illinois (the "Company"), proposes to issue and sell to the several parties named in Schedule I hereto (the "Initial Purchasers"), for whom you (the "Representatives") are acting as representatives, an additional $200,000,000 principal amount of the Company's outstanding First Mortgage 6.15% Bonds, Series 98 Due 2012 (the "Securities"). The Securities are to be issued under the Company's Mortgage, dated as of July 1, 1923, as amended and supplemented through the date hereof, and as further supplemented by the Supplemental Indenture dated as of June 1, 2002 (the "Supplement") from the Company to BNY Midwest Trust Company, as trustee (the "Trustee") and D.G. Donovan as co-trustee (the "Co-Trustee"). As used herein, the term "Mortgage" refers to the Company's Mortgage referred to above together with any and all amendments or supplements thereto, including the Supplement. The Securities will have the benefit of a Registration Rights Agreement, dated as of the Closing Date (the "Registration Rights Agreement"), between the Company and the Initial Purchasers, pursuant to which the Company has agreed to register the Securities under the Act subject to the terms and conditions therein specified. Certain terms used herein are defined in Section 17 hereof.

The sale of the Securities to the Initial Purchasers will be made without registration of the Securities under the Act in reliance upon an exemption from the registration requirements of the Act.

In connection with the sale of the Securities, the Company has prepared a preliminary offering memorandum, dated June 13, 2002 (as amended or supplemented at the Execution Time, including any information incorporated by reference therein, the "Preliminary Memorandum"), and a final offering memorandum, dated June 13, 2002 (as amended or supplemented at the Execution Time, including any information incorporated by reference therein as of its date, the "Final Memorandum"). Each of the Preliminary Memorandum and the Final Memorandum sets forth certain information concerning the Company and the Securities. The Company hereby confirms that it has authorized the use of the Preliminary Memorandum

and the Final Memorandum, and any amendment or supplement thereto, in connection with the offer and sale of the Securities by the Initial Purchasers.

1. REPRESENTATIONS AND WARRANTIES. The Company represents and warrants to each Initial Purchaser as set forth below in this Section 1.

(a) The Preliminary Memorandum, at the date thereof, did not contain any untrue statement of a material fact or omit to state any material fact necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading. At the Execution Time and on the Closing Date, the Final Memorandum did not, and will not (and any amendment or supplement thereto, at the date thereof and at the Closing Date, will not), contain any untrue statement of a material fact or omit to state any material fact necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading; PROVIDED, HOWEVER, that the Company makes no representation or warranty as to the information contained in or omitted from the Preliminary Memorandum or the Final Memorandum, or any amendment or supplement thereto, in reliance upon and in conformity with information furnished in writing to the Company by or on behalf of the Initial Purchasers through the Representatives specifically for inclusion therein.

(b) Neither the Company, nor any of its Affiliates, nor any person acting on its or their behalf (it being understood that the Company makes no representation or warranty with respect to the Representatives or any Initial Purchaser) has, directly or indirectly, made offers or sales of any security, or solicited offers to buy any security, under circumstances that would require the registration of the Securities under the Act.

(c) Neither the Company, nor any of its Affiliates, nor any person acting on its or their behalf (it being understood that the Company makes no representation or warranty with respect to the Representatives or any Initial Purchaser) has engaged in any form of general solicitation or general advertising (within the meaning of Regulation D) in connection with any offer or sale of the Securities in the United States.

(d) The Securities satisfy the eligibility requirements of Rule 144A(d)(3) under the Act.

(e) The Company has not paid or agreed to pay to any person any compensation for soliciting another to purchase any Securities of the Company (except as contemplated by this Agreement).

(f) The Company has not taken, directly or indirectly, any action designed to cause or which has constituted or which might reasonably be expected to cause or result, under the Exchange Act or otherwise, in the stabilization or manipulation of the price of any security of the Company to facilitate the sale or resale of the Securities.

(g) The statements in the Final Memorandum under the headings "Description of Bonds" and "Exchange Offer; Registration Rights" fairly summarize the matters therein described.

(h) This Agreement has been duly authorized, executed and delivered by the Company; the Mortgage has been duly authorized and, assuming due authorization, execution and delivery of the Supplement by the Trustee and due execution and delivery of the Supplement by the Co-Trustee, when executed and delivered by the Company, will constitute a legal, valid, binding instrument enforceable against the Company in accordance with its terms (subject, as to the enforcement of remedies, to applicable bankruptcy, reorganization, insolvency, moratorium or other laws affecting creditors' rights generally from time to time in effect and to general principles of equity); the Securities have been duly authorized, and, when executed and authenticated in accordance with the provisions of the Mortgage and delivered to and paid for by the Initial Purchasers, will have been duly executed and delivered by the Company and will constitute the legal, valid and binding obligations of the Company entitled to the benefits of the Mortgage (subject, as to the enforcement of remedies, to applicable bankruptcy, insolvency, moratorium or other laws affecting creditors' rights generally from time to time in effect and to general principles of equity); and the Registration Rights Agreement has been duly authorized and, when executed and delivered by the Company, will constitute the legal, valid, binding and enforceable instrument of the Company (subject, as to the enforcement of remedies, to applicable bankruptcy, reorganization, insolvency, moratorium or other laws affecting creditors' rights generally from time to time in effect and to general principles of equity).

(i) The Company has filed with the Illinois Commerce Commission a petition with respect to the issuance and sale of the Securities and said Commission has issued its order authorizing and approving such issuance and sale. No consent of or approval by any other public board or body or administrative agency, federal or state, is necessary in connection with the transactions contemplated by this Agreement, the Mortgage or the Registration Rights Agreement, except as may be required under the blue sky laws of any jurisdiction in connection with the purchase and distribution of the Securities by the Initial Purchasers in the manner contemplated herein and in the Final Memorandum and as may be required under the Act in connection with the transactions contemplated by the Registration Rights Agreement.

(j) Neither the Company nor any significant subsidiary, as defined in Rule 1-02 of Regulation S-X of the Securities and Exchange Commission ("significant subsidiary") is in violation of its articles of incorporation, or in default in the performance or observance of any material obligation, agreement, covenant or condition contained in any mortgage or any material contract, lease, note or other instrument to which it is a party or by which it may be bound, or materially in violation of any law, administrative regulation or administrative, arbitration or court order to which it is subject or bound, except in each case to such extent as may be set forth in the Final Memorandum; and the execution and delivery of this Agreement, the incurrence of the obligations herein set forth and the consummation of the transactions herein contemplated will not conflict with or constitute a breach of, or default under, the articles of incorporation or by-laws of the Company or any mortgage, contract, lease, note or other instrument to which the Company or any significant subsidiary is a party or by which it or any significant subsidiary may be bound, or any law, administrative regulation or administrative, arbitration or court order to which it is subject or bound.

(k) The Company has good and sufficient title to all property described or referred to in the Mortgage and purported to be conveyed thereby, subject only to the lien of the Mortgage and permitted liens as therein defined (except as to property released from the lien of

the Mortgage in connection with the sale or other disposition thereof, and certain other exceptions which are not material in the aggregate). The Mortgage has been duly filed for recordation in such manner and in such places as is required by law in order to give constructive notice of, establish, preserve and protect the lien of the Mortgage. The Mortgage constitutes a valid, direct first mortgage lien on substantially all property (including franchises) now owned by the Company, except property expressly excepted by the terms of the Mortgage, subject to permitted liens as defined therein. The Mortgage will constitute a valid, direct first mortgage lien on all property of the character of that now subject to the lien of the Mortgage hereafter acquired by the Company, subject to permitted liens as defined in the Mortgage, and to liens, if any, existing or placed on such after-acquired property at the time of the acquisition thereof.

(l) The financial statements included or incorporated by reference in the Final Memorandum present fairly in all material respects the financial position, results of operations and cash flows of the Company at the respective dates and for the respective periods specified and, except as otherwise stated in the Final Memorandum, said financial statements have been prepared in conformity with generally accepted accounting principles applied on a consistent basis during the periods involved. The Company has no material contingent obligation which is not disclosed in the Final Memorandum.

(m) Except as set forth in or contemplated by the Final Memorandum, no material transaction has been entered into by the Company otherwise than in the ordinary course of business and no materially adverse change has occurred in the condition, financial or otherwise, of the Company, in each case since the respective dates as of which information is given in the Final Memorandum.

(n) The Company has been duly incorporated and is validly existing as a corporation in good standing under the laws of the State of Illinois with corporate power and authority to own its properties and conduct its business as described in the Final Memorandum.

(o) Each significant subsidiary of the Company has been duly incorporated and is validly existing as a corporation in good standing under the laws of the jurisdiction of its incorporation; all of the issued and outstanding capital stock of each significant subsidiary has been duly and validly issued and is fully paid and nonassessable; and all of the capital stock of each significant subsidiary is owned by the Company free and clear of any pledge, lien, encumbrance, claim or equity.

(p) There is no pending or threatened suit or proceeding before any court or governmental agency, authority or body or any arbitration involving the Company or any of its significant subsidiaries required to be disclosed in the Final Memorandum which is not adequately disclosed in the Final Memorandum.

(q) The franchise granted to the Company by the City Council of the City of Chicago under an ordinance effective January 1, 1992, is valid and subsisting and duly authorizes the Company to engage in the electric utility business conducted by it in such City. The several franchises of the Company outside the City of Chicago are valid and subsisting and authorize the Company to carry on its utility business in the several communities, capable of granting franchises, located in the territory served by the Company outside the City of Chicago (with immaterial exceptions).

(r) PricewaterhouseCoopers LLP, the accountants who certified certain of the financial statements included or incorporated by reference in the Final Memorandum, are independent public accountants as required by the Act and the applicable published rules and regulations thereunder.

Any certificate signed by any officer of the Company and delivered to the Representatives or counsel for the Representatives in connection with the offering of the Securities shall be deemed a representation and warranty by the Company, as to matters covered thereby, to each Initial Purchaser.

2. PURCHASE AND SALE. Subject to the terms and conditions and in reliance upon the representations and warranties herein set forth, the Company agrees to sell to each Initial Purchaser, and each Initial Purchaser agrees, severally and not jointly, to purchase from the Company, at a purchase price of 101.489% of the principal amount thereof, plus accrued interest from March 13, 2002 to the Closing Date, the principal amount of Securities set forth opposite such Initial Purchaser's name in Schedule I hereto.

3. DELIVERY AND PAYMENT. Delivery of and payment for the Securities shall be made at 10:00 A.M., New York City time, on June 20, 2002, or at such time on such later date as the Representatives shall designate, which date and time may be postponed by agreement between the Representatives and the Company or as provided in Section 9 hereof (such date and time of delivery and payment for the Securities being herein called the "Closing Date"). Delivery of the Securities shall be made to the Representatives for the respective accounts of the several Initial Purchasers against payment by the several Initial Purchasers through the Representatives of the purchase price thereof to or upon the order of the Company by wire transfer payable in same-day funds to the account specified by the Company. Delivery of the Securities shall be made through the facilities of The Depository Trust Company.

4. OFFERING BY INITIAL PURCHASERS. Each Initial Purchaser, severally and not jointly, represents and warrants to and agrees with the Company, which agreement shall be confirmed by such Initial Purchaser's purchase of the Securities, that:

(a) It has not offered or sold, and will not offer or sell, any Securities except to those persons it reasonably believes to be qualified institutional buyers (as defined in Rule 144A under the Act) and that, in connection with each such sale, it has taken or will take reasonable steps to ensure that the purchaser of such Securities is aware that such sale is being made in reliance on Rule 144A.

(b) Neither it nor any person acting on its behalf has made or will make offers or sales of the Securities by means of any form of general solicitation or general advertising (within the meaning of Regulation D) in the United States.

5. AGREEMENTS. The Company agrees with each Initial Purchaser that:

(a) The Company will furnish to each Initial Purchaser, without charge, during the period referred to in paragraph (c) below, as many copies of the Final Memorandum and any amendments and supplements thereto as it may reasonably request.

(b) The Company will advise each Initial Purchaser promptly of any proposal to amend or supplement the Final Memorandum and will not effect such amendment or supplement without the consent of the Initial Purchasers, which consent shall not be unreasonably withheld. Neither the consent of the Initial Purchasers, nor the Initial Purchasers' delivery of any such amendment or supplement, shall constitute a waiver of any of the conditions set forth in
Section 6.

(c) If at any time prior to the completion of the sale of the Securities by the Initial Purchasers (as determined by the Representatives), any event occurs as a result of which the Final Memorandum, as then amended or supplemented, would include any untrue statement of a material fact or omit to state any material fact necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading, or if it should be necessary to amend or supplement the Final Memorandum to comply with applicable law, the Company promptly (i) will notify the Representatives of any such event; (ii) subject to the requirements of paragraph (b) of this Section 5, will prepare an amendment or supplement that will correct such statement or omission or effect such compliance; and (iii) will supply any supplemented or amended Final Memorandum to the several Initial Purchasers without charge in such quantities as you may reasonably request.

(d) The Company will arrange, if necessary, for the qualification of the Securities for sale by the Initial Purchasers under the laws of such jurisdictions as the Initial Purchasers may designate and will maintain such qualifications in effect so long as required for the sale of the Securities; PROVIDED that in no event shall the Company be obligated to qualify to do business in any jurisdiction where it is not now so qualified or to take any action that would subject it to service of process in suits (other than those arising out of the offering or sale of the Securities) in any jurisdiction where it is not now so subject. The Company will promptly advise the Representatives of the receipt by the Company of any notification with respect to the suspension of the qualification of the Securities for sale in any jurisdiction or the initiation or threatening of any proceeding for such purpose.

(e) From the date hereof through the third anniversary of the Closing Date, the Company will not, and will not permit any of its Affiliates to, resell any Securities that have been acquired by any of them.

(f) None of the Company, any of its Affiliates, or any person acting on its or their behalf will, directly or indirectly, make offers or sales of any security, or solicit offers to buy any security, under circumstances that would require the registration of the Securities under the Act.

(g) None of the Company, any of its Affiliates, or any person acting on its or their behalf will engage in any form of general solicitation or general advertising (within the meaning of Regulation D) in connection with any offer or sale of the Securities in the United States.

(h) So long as any of the Securities are "restricted securities" within the meaning of Rule 144(a)(3) under the Act, the Company will, during any period in which it is not subject to and in compliance with Section 13 or 15(d) of the Exchange Act or it is not exempt from such reporting requirements pursuant to and in compliance with Rule 12g3-2(b) under the

Exchange Act, provide to each holder of such restricted securities and to each prospective purchaser (as designated by such holder) of such restricted securities, upon the request of such holder or prospective purchaser, any information required to be provided by Rule 144A(d)(4) under the Act. This covenant is intended to be for the benefit of the holders, and the prospective purchasers designated by such holders, from time to time of such restricted securities.

(i) None of the Company, any of its Affiliates or any person acting on its or their behalf will engage in any directed selling efforts with respect to the Securities.

(j) The Company will cooperate with the Representatives and use its best efforts to permit the Securities to be eligible for clearance and settlement through The Depository Trust Company.

(k) The Company will not for a period of 14 days following the Execution Time, without the prior written consent of Barclays Capital Inc., offer, sell or contract to sell, or otherwise dispose of (or enter into any transaction which is designed to, or might reasonably be expected to, result in the disposition (whether by actual disposition or effective economic disposition due to cash settlement or otherwise) by the Company, directly or indirectly, or announce the offering of, any long-term debt securities issued or guaranteed by the Company (other than the Securities).

(l) The Company will not take, directly or indirectly, any action designed to or which has constituted or which might reasonably be expected to cause or result, under the Exchange Act or otherwise, in stabilization or manipulation of the price of any security of the Company to facilitate the sale or resale of the Securities.

(m) The Company agrees to pay the costs and expenses relating to the following matters: (i) the preparation of the Supplement and the Registration Rights Agreement, the issuance of the Securities and the fees of the Trustee;
(ii) the preparation, printing or reproduction of the Preliminary Memorandum and Final Memorandum and each amendment or supplement to either of them; (iii) the printing (or reproduction) and delivery (including postage, air freight charges and charges for counting and packaging) of such copies of the Final Memorandum, and all amendments or supplements to it, as may, be reasonably requested for use in connection with the offering and sale of the Securities; (iv) the preparation, printing, authentication, issuance and delivery of certificates for the Securities, including any stamp or transfer taxes in connection with the original issuance and sale of the Securities; (v) the printing (or reproduction) and delivery of this Agreement, any blue sky memorandum and all other agreements or documents printed (or reproduced) and delivered in connection with the offering of the Securities; (vi) any registration or qualification of the Securities for offer and sale under the securities or blue sky laws of the several states (including filing fees and the reasonable fees and expenses of counsel for the Initial Purchasers relating to such registration and qualification); (vii) the transportation and other expenses incurred by or on behalf of Company representatives in connection with presentations to prospective purchasers of the Securities; (viii) the fees and expenses of the Company's accountants and counsel (including local and special counsel); (ix) the fees and expenses of any rating agencies rating the Securities and (x) all other costs and expenses incident to the performance by the Company of its obligations hereunder.

6. CONDITIONS TO THE OBLIGATIONS OF THE INITIAL PURCHASERS. The obligations of the Initial Purchasers to purchase the Securities shall be subject to the accuracy of the representations and warranties on the part of the Company contained herein at the Execution Time and the Closing Date, to the accuracy of the statements of the Company made in any certificates pursuant to the provisions hereof, to the performance by the Company of its obligations hereunder and to the following additional conditions:

(a) Sidley Austin Brown & Wood, counsel for the Company, shall have furnished to the Representatives its opinion, dated the Closing Date and addressed to the Representatives, in form and substance satisfactory to each of the Representatives and its counsel.

(b) The Representatives shall have received from Winston & Strawn, counsel for the Initial Purchasers, such opinion or opinions, dated the Closing Date and addressed to the Representatives, with respect to the issuance and sale of the Securities, the Mortgage, the Registration Rights Agreement, the Final Memorandum (as amended or supplemented at the Closing Date) and other related matters as the Representatives may reasonably require, and the Company shall have furnished to such counsel such documents as they request for the purpose of enabling them to pass upon such matters.

(c) The Company shall have furnished to the Representatives a certificate of the Company, signed by the Treasurer of the Company, dated the Closing Date, to the effect that the signer of such certificate has carefully examined the Final Memorandum, any amendment or supplement to the Final Memorandum and this Agreement and that:

(i) the representations and warranties of the Company in this Agreement are true and correct in all material respects on and as of the Closing Date with the same effect as if made on the Closing Date, and the Company has complied with all the agreements and satisfied all the conditions on its part to be performed or satisfied hereunder at or prior to the Closing Date; and

(ii) since the date of the most recent financial statements included in the Final Memorandum (exclusive of any amendment or supplement thereto), there has been no material adverse change in the financial condition, business or properties of the Company and its subsidiaries, taken as a whole, whether or not arising from transactions in the ordinary course of business, except as set forth in or contemplated by the Final Memorandum (exclusive of any amendment or supplement thereto).

(d) At the Execution Time and at the Closing Date, the Company shall have requested and caused PricewaterhouseCoopers LLP to furnish to the Representatives letters, dated respectively as of the Execution Time and as of the Closing Date, in form and substance satisfactory to the Representatives.

(e) Subsequent to the Execution Time or, if earlier, the dates as of which information is given in the Final Memorandum (exclusive of any amendment or supplement thereto), there shall not have been (i) any change or decrease specified in the letter or letters referred to in paragraph (d) of this Section 6; or (ii) any change, or any development involving a

prospective change, in or affecting the financial condition, business or properties of the Company and its subsidiaries, taken as a whole, whether or not arising from transactions in the ordinary course of business, except as set forth in or contemplated in the Final Memorandum (exclusive of any amendment or supplement thereto) the effect of which, in any case referred to in clause (i) or (ii) above, is, in the sole judgment of the Representatives, so material and adverse as to make it impractical or inadvisable to market the Securities as contemplated by the Final Memorandum (exclusive of any amendment or supplement thereto).

(f) On the Closing Date, (i) the Securities shall be rated "A3" by Moody's Investors Service, Inc. and "A-" by Standard & Poor's Rating Services, and the Company shall have delivered to the Representatives evidence satisfactory to the Representatives confirming that the Securities have such ratings, and (ii) since the Execution Time, there shall not have occurred a downgrading in the rating assigned to the Securities or any of the Company's first mortgage bonds or commercial paper by any "nationally recognized statistical rating agency", as that term is defined by the Commission for purposes of Rule 436(g)(2) under the Act, and no such securities rating agency shall have publicly announced that it has under surveillance or review, with possible negative implications, its rating of the Securities or any of the Company's other debt securities.

(g) On the Closing Date, the Initial Purchasers shall have received the Registration Rights Agreement duly executed and delivered by the Company and such agreement shall be in full force and effect according to its terms at all times from and after the Closing Date.

(h) Prior to the Closing Date, the Company shall have furnished to the Representatives such further information, certificates and documents as the Representatives may reasonably request.

(i) If any of the conditions specified in this Section 6 shall not have been fulfilled in all material respects when and as provided in this Agreement, or if any of the opinions and certificates mentioned above or elsewhere in this Agreement shall not be in all material respects reasonably satisfactory in form and substance to the Representatives and counsel for the Initial Purchasers, this Agreement and all obligations of the Initial Purchasers hereunder may be cancelled at, or at any time prior to, the Closing Date by the Representatives. Notice of such cancellation shall be given to the Company in writing or by telephone or facsimile confirmed in writing.

The documents required to be delivered by this Section 6 will be delivered at the office of counsel for the Company, at Sidley Austin Brown & Wood, 10 South Dearborn Street, Suite 5500, Chicago, Illinois 60603, on the Closing Date.

7. REIMBURSEMENT OF EXPENSES. If the sale of the Securities provided for herein is not consummated because any condition to the obligations of the Initial Purchasers set forth in Section 6 hereof is not satisfied, because of any termination pursuant to Section 10 hereof or because of any refusal, inability or failure on the part of the Company to perform any agreement herein or comply with any provision hereof other than by reason of a default by any of the Initial Purchasers, the Company will reimburse the Initial Purchasers severally through Barclays Capital Inc. on demand for all out-of-pocket expenses (including reasonable fees and

disbursements of counsel) that shall have been incurred by them in connection with the proposed purchase and sale of the Securities.

8. INDEMNIFICATION AND CONTRIBUTION. (a) The Company agrees to indemnify and hold harmless each Initial Purchaser, the directors, officers, employees and agents of each Initial Purchaser and each person who controls any Initial Purchaser within the meaning of either the Act or the Exchange Act against any and all losses, claims, damages or liabilities, joint or several, to which they or any of them may become subject under the Act, the Exchange Act or other Federal or state statutory law or regulation, at common law or otherwise, insofar as such losses, claims, damages or liabilities (or actions in respect thereof) arise out of or are based upon any untrue statement or alleged untrue statement of a material fact contained in the Preliminary Memorandum, the Final Memorandum (or in any supplement or amendment thereto) or any information provided by the Company to any holder or prospective purchaser of Securities pursuant to Section 5(h), or in any amendment thereof or supplement thereto, or arise out of or are based upon the omission or alleged omission to state therein a material fact required to be stated therein or necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading, and agrees to reimburse each such indemnified party, as incurred, for any legal or other expenses reasonably incurred by them in connection with investigating or defending any such loss, claim, damage, liability or action; PROVIDED, HOWEVER, that the Company will not be liable in any such case to the extent that any such loss, claim, damage or liability arises out of or is based upon any such untrue statement or alleged untrue statement or omission or alleged omission made in the Preliminary Memorandum or the Final Memorandum, or in any amendment thereof or supplement thereto, in reliance upon and in conformity with written information furnished to the Company by or on behalf of any Initial Purchasers through the Representatives specifically for inclusion therein; PROVIDED, FURTHER, that the foregoing indemnity with respect to any untrue statement contained in or omission from the Preliminary Memorandum shall not inure to the benefit of any Initial Purchaser (or any of the directors, officers, employees and agents of such Initial Purchaser or any person controlling such Initial Purchaser) from whom the person asserting any such loss, claim, damage or liability purchased the Securities which are the subject thereof if such person did not receive a copy of the Final Memorandum (or the Final Memorandum as then amended or supplemented if the Company shall have furnished any amendments or supplements thereto) at or prior to the confirmation of the sale of such Securities to such person in any case where such delivery is required by the Act and the untrue statement or omission of a material fact contained in such Preliminary Memorandum was corrected in the Final Memorandum (or the Final Memorandum as so amended or supplemented if the Company shall have furnished any amendments or supplements thereto), and it is finally judicially determined that such delivery was required to be made under the Act and was not so made. This indemnity agreement will be in addition to any liability which the Company may otherwise have.

(b) Each Initial Purchaser severally and not jointly agrees to indemnify and hold harmless the Company, and each of its directors, officers, employees and agents, and each person who controls the Company within the meaning of either the Act or the Exchange Act, to the same extent as the foregoing indemnity from the Company to each Initial Purchaser, but only with reference to written information relating to such Initial Purchaser furnished to the Company by or on behalf of such Initial Purchaser through the Representatives specifically for inclusion in the Preliminary Memorandum or the Final Memorandum (or in any amendment or supplement

thereto). This indemnity agreement will be in addition to any liability which any Initial Purchaser may otherwise have. The Company acknowledges that the statements set forth in the last paragraph of the cover page regarding the delivery of the Securities, and, under the heading "Plan of Distribution" in the Preliminary Memorandum and the Final Memorandum, (i) the fourth sentence of the fifth paragraph related to market-making activities; (ii) the sixth paragraph related to stabilization, syndicate covering transactions and penalty bids; and
(iii) the eighth paragraph related to one of the Representatives and its affiliates, constitute the only information furnished in writing by or on behalf of the Initial Purchasers for inclusion in the Preliminary Memorandum or the Final Memorandum (or in any amendment or supplement thereto).

(c) Promptly after receipt by an indemnified party under this Section 8 of notice of the commencement of any action, such indemnified party will, if a claim in respect thereof is to be made against the indemnifying party under this
Section 8, notify the indemnifying party in writing of the commencement thereof; but the failure so to notify the indemnifying party (i) will not relieve it from liability under paragraph (a) or (b) above unless and to the extent it did not otherwise learn of such action and such failure results in the forfeiture by the indemnifying party of substantial rights and defenses; and (ii) will not, in any event, relieve the indemnifying party from any obligations to any indemnified party other than the indemnification obligation provided in paragraph (a) or (b) above. The indemnifying party shall be entitled to appoint counsel of the indemnifying party's choice at the indemnifying party's expense to represent the indemnified party in any action for which indemnification is sought (in which case the indemnifying party shall not thereafter be responsible for the fees and expenses of any separate counsel retained by the indemnified party or parties except as set forth below); PROVIDED, HOWEVER, that such counsel shall be satisfactory to the indemnified party. Notwithstanding the indemnifying party's election to appoint counsel to represent the indemnified party in an action, the indemnified party shall have the right to employ separate counsel (including local counsel), and the indemnifying party shall bear the reasonable fees, costs and expenses of such separate counsel if (i) the use of counsel chosen by the indemnifying party to represent the indemnified party would present such counsel with a conflict of interest; (ii) the actual or potential defendants in, or targets of, any such action include both the indemnified party and the indemnifying party and the indemnified party shall have reasonably concluded that there may be legal defenses available to it and/or other indemnified parties which are different from or additional to those available to the indemnifying party; (iii) the indemnifying party shall not have employed counsel satisfactory to the indemnified party to represent the indemnified party within a reasonable time after notice of the institution of such action; or (iv) the indemnifying party shall authorize the indemnified party to employ separate counsel at the expense of the indemnifying party. An indemnifying party will not, without the prior written consent of the indemnified parties, settle or compromise or consent to the entry of any judgment with respect to any pending or threatened claim, action, suit or proceeding in respect of which indemnification or contribution may be sought hereunder (whether or not the indemnified parties are actual or potential parties to such claim or action) unless such settlement, compromise or consent includes an unconditional release of each indemnified party from all liability arising out of such claim, action, suit or proceeding.

(d) In the event that the indemnity provided in paragraph (a) or (b) of this Section 8 is for any reason held to be unenforceable by an indemnified party although applicable in accordance with its terms, the Company and the Initial Purchasers agree to contribute to the

aggregate losses, claims, damages and liabilities (including legal or other expenses reasonably incurred in connection with investigating or defending same) (collectively "Losses") to which the Company and one or more of the Initial Purchasers may be subject in such proportion as is appropriate to reflect the relative benefits received by the Company on the one hand and by the Initial Purchasers on the other from the offering of the Securities; PROVIDED, HOWEVER, that in no case shall any Initial Purchaser (except as may be provided in any agreement among the Initial Purchasers relating to the offering of the Securities) be responsible for any amount in excess of the purchase discount or commission applicable to the Securities purchased by such Initial Purchaser hereunder; PROVIDED, FURTHER, that each Initial Purchaser's obligation to contribute to Losses hereunder shall be several and not joint. If the allocation provided by the immediately preceding sentence is unavailable for any reason, the Company and the Initial Purchasers shall contribute in such proportion as is appropriate to reflect not only such relative benefits but also the relative fault of the Company on the one hand and of the Initial Purchasers on the other in connection with the statements or omissions which resulted in such Losses, as well as any other relevant equitable considerations. Benefits received by the Company shall be deemed to be equal to the total net proceeds from the offering (before deducting expenses) received by it, and benefits received by the Initial Purchasers shall be deemed to be equal to the total purchase discounts and commissions in each case set forth on the cover of the Final Memorandum. Relative fault shall be determined by reference to, among other things, whether any untrue or any alleged untrue statement of a material fact or the omission or alleged omission to state a material fact relates to information provided by the Company on the one hand or the Initial Purchasers on the other, the intent of the parties and their relative knowledge, information and opportunity to correct or prevent such untrue statement or omission. The Company and the Initial Purchasers agree that it would not be just and equitable if contribution were determined by pro rata allocation or any other method of allocation which does not take account of the equitable considerations referred to above. Notwithstanding the provisions of this paragraph (d), no person guilty of fraudulent misrepresentation (within the meaning of Section 11(f) of the Act) shall be entitled to contribution from any person who was not guilty of such fraudulent misrepresentation. For purposes of this Section 8, each person who controls an Initial Purchaser within the meaning of either the Act or the Exchange Act and each director, officer, employee and agent of an Initial Purchaser shall have the same rights to contribution as such Initial Purchaser, and each person who controls the Company within the meaning of either the Act or the Exchange Act and each officer, director, employee or agent of the Company shall have the same rights to contribution as the Company, subject in each case to the applicable terms and conditions of this paragraph (d).

9. DEFAULT BY AN INITIAL PURCHASER. If any one or more Initial Purchasers shall fail to purchase and pay for any of the Securities agreed to be purchased by such Initial Purchaser hereunder and such failure to purchase shall constitute a default in the performance of its or their obligations under this Agreement, the remaining Initial Purchasers shall be obligated severally to take up and pay for (in the respective proportions which the amount of Securities set forth opposite their names in Schedule I hereto bears to the aggregate amount of Securities set forth opposite the names of all the remaining Initial Purchasers) the Securities which the defaulting Initial Purchaser or Initial Purchasers agreed but failed to purchase; PROVIDED, HOWEVER, that in the event that the aggregate amount of Securities which the defaulting Initial Purchaser or Initial Purchasers agreed but failed to purchase shall exceed 10% of the aggregate amount of Securities set forth in Schedule I hereto, the remaining Initial Purchasers shall have the right to purchase

all, but shall not be under any obligation to purchase any, of the Securities, and if such nondefaulting Initial Purchasers do not purchase all the Securities, this Agreement will terminate without liability to any nondefaulting Initial Purchaser or the Company. In the event of a default by any Initial Purchaser as set forth in this Section 9, the Closing Date shall be postponed for such period, not exceeding five Business Days, as the Representatives shall determine in order that the required changes in the Final Memorandum or in any other documents or arrangements may be effected. Nothing contained in this Agreement shall relieve any defaulting Initial Purchaser of its liability, if any, to the Company or any nondefaulting Initial Purchaser for damages occasioned by its default hereunder.

10. TERMINATION. This Agreement shall be subject to termination in the absolute discretion of the Representatives, by notice given to the Company prior to delivery of and payment for the Securities, if at any time after the date hereof and prior to the delivery of and payment for the Securities (i) trading in Exelon Corporation's common stock shall have been suspended by the Commission or the New York Stock Exchange or trading in securities generally on the New York Stock Exchange shall have been suspended or limited or minimum prices shall have been established on such Exchange; (ii) a banking moratorium shall have been declared either by Federal or New York State authorities; or (iii) there shall have occurred any outbreak or escalation of hostilities, declaration by the United States of a national emergency or war or other calamity or crisis the effect of which on financial markets is such as to make it, in the sole judgment of the Representatives, impracticable or inadvisable to proceed with the offering or delivery of the Securities as contemplated by the Final Memorandum (exclusive of any amendment or supplement thereto).

11. INDEMNITIES TO SURVIVE. The respective agreements, representations, warranties, indemnities and other statements of the Company or its officers and of the Initial Purchasers set forth in or made pursuant to this Agreement will remain in full force and effect, regardless of any investigation made by or on behalf of the Initial Purchasers or the Company or any of the officers, directors or controlling persons referred to in Section 8 hereof, and will survive delivery of and payment for the Securities. The provisions of Sections 7 and 8 hereof shall survive the termination or cancellation of this Agreement.

12. NOTICES. All communications hereunder will be in writing and effective only on receipt, and, if sent to the Representatives, will be mailed, delivered or telefaxed to the Barclays Capital Inc. Syndicate Desk (fax no.:
(212) 412-1623) and confirmed to Barclays Capital Inc. at 222 Broadway, New York, New York 10038 Attention: Syndicate Desk; or, if sent to the Company, will be mailed, delivered or telefaxed to Exelon Corporation, 10 South Dearborn Street, 37th Floor, P.O. Box 805379, Chicago, Illinois 60680-5379, Attention:
Vice President and Treasurer (fax no.: (312) 394-5440) and confirmed to the General Counsel of Exelon Corporation (fax no.: (312) 394-2900).

13. SUCCESSORS. This Agreement will inure to the benefit of and be binding upon the parties hereto and their respective successors and the officers and directors and controlling persons referred to in Section 8 hereof, and, except as expressly set forth in Section 5(h) hereof, no other person will have any right or obligation hereunder.

14. APPLICABLE LAW. This Agreement will be governed by and construed in accordance with the laws of the State of New York applicable to contracts made and to be performed within the State of New York.

15. COUNTERPARTS. This Agreement may be executed in one or more counterparts, each of which shall constitute an original and all of which together shall constitute one and the same instrument.

16. HEADINGS. The section headings used herein are for convenience only and shall not affect the construction hereof.

17. DEFINITIONS. The terms which follow, when used in this Agreement, shall have the meanings indicated.

"Act" shall mean the Securities Act of 1933, as amended, and the rules and regulations of the Commission promulgated thereunder.

"Affiliate" shall have the meaning specified in Rule 501(b) of Regulation D.

"Business Day" shall mean any day other than a Saturday, a Sunday or a legal holiday or a day on which banking institutions or trust companies are authorized or obligated by law to close in the City of New York.

"Commission" shall mean the Securities and Exchange Commission.

"Exchange Act" shall mean the Securities Exchange Act of 1934, as amended, and the rules and regulations of the Commission promulgated thereunder.

"Execution Time" shall mean the date and time that this Agreement is executed and delivered by the parties hereto.

"NASD" shall mean the National Association of Securities Dealers, Inc.

"Regulation D" shall mean Regulation D under the Act.

[signature page follows]

If the foregoing is in accordance with your understanding of our agreement, please sign and return to us the enclosed duplicate hereof, whereupon this Agreement and your acceptance shall represent a binding agreement between the Company and the several Initial Purchasers.

Very truly yours,

COMMONWEALTH EDISON COMPANY

By:

Name:
Title:

The foregoing Agreement is hereby
confirmed and accepted as of the
date first above written.

Barclays CAPITAL INC.
FIRST UNION SECURITIES, INC.

By: Barclays Capital Inc.

By:
Name:
Title:

For themselves and the other several
Initial Purchasers named in
Schedule I to the foregoing
Agreement.

SCHEDULE I 

                                                                                 Principal
                                                                                 Amount of
                                                                                 Securities
                                                                                   to be
Initial Purchasers                                                               Purchased
------------------                                                             -------------
Barclays Capital Inc......................................................     $  70,000,000
First Union Securities, Inc...............................................        70,000,000
ABN AMRO Incorporated.....................................................        18,000,000
Dresdner Kleinwort Wasserstein-Grantchester, Inc..........................        18,000,000
J. P. Morgan Securities Inc...............................................        18,000,000
Loop Capital Markets, LLC.................................................         6,000,000
                                                                               -------------
              Total.......................................................     $ 200,000,000

EXECUTION COPY
EXHIBIT 4.4

COMMONWEALTH EDISON COMPANY

$400,000,000

First Mortgage 6.15% Bonds, Series 98 Due 2012

REGISTRATION RIGHTS AGREEMENT

New York, New York
March 13, 2002

Salomon Smith Barney Inc.
J.P. Morgan Securities Inc.
As Representatives of the Initial Purchasers c/o Salomon Smith Barney Inc.
388 Greenwich Street
New York, New York 10013

Ladies and Gentlemen:

Commonwealth Edison Company, a corporation organized under the laws of the State of Illinois (the "Company"), proposes to issue and sell to certain purchasers (the "Initial Purchasers") the Company's First Mortgage 6.15% Bonds, Series Due 2012 (the "Securities"), upon the terms set forth in a purchase agreement dated as of March 6, 2002 (the "Purchase Agreement"), relating to the initial placement of the Securities (the "Initial Placement"). To induce the Initial Purchasers to enter into the Purchase Agreement and to satisfy a condition of your obligations thereunder, the Company agrees with you for your benefit and the benefit of the holders from time to time of the Securities (including the Initial Purchasers) (each a "Holder" and, together, the "Holders"), as follows:

1. DEFINITIONS. Each of the capitalized terms used herein without definition shall have the meaning set forth in the Purchase Agreement. As used in this Agreement, the following capitalized defined terms shall have the following meanings:

"Act" shall mean the Securities Act of 1933, as amended, and the rules and regulations of the Commission promulgated thereunder.

"Affiliate" of any specified Person shall mean any other Person that, directly or indirectly, is in control of, is controlled by, or is under common control with, such specified Person. For purposes of this definition, control of a Person shall mean the power, direct or indirect, to direct or cause the direction of the management and policies of such Person whether by contract or otherwise; and the terms "controlling" and "controlled" shall have meanings correlative to the foregoing.

"Broker-Dealer" shall mean any broker or dealer registered as such under the Exchange Act.

"Business Day" shall mean any day other than a Saturday, a Sunday or a legal holiday or a day on which banking institutions or trust companies are authorized or obligated by law to close in New York City.

"Commission" shall mean the Securities and Exchange Commission.

"Exchange Act" shall mean the Securities Exchange Act of 1934, as amended, and the rules and regulations of the Commission promulgated thereunder.

"Exchange Offer Registration Period" shall mean the one-year period following the consummation of the Registered Exchange Offer, exclusive of any period during which any stop order shall be in effect suspending the effectiveness of the Exchange Offer Registration Statement.

"Exchange Offer Registration Statement" shall mean a registration statement of the Company on an appropriate form under the Act with respect to the Registered Exchange Offer, all amendments and supplements to such registration statement, including post-effective amendments thereto, in each case including the Prospectus contained therein, all exhibits thereto and all material incorporated by reference therein.

"Exchanging Dealer" shall mean any Holder (which may include any Initial Purchaser) that is a Broker-Dealer and elects to exchange for New Securities any Securities that it acquired for its own account as a result of market-making activities or other trading activities (but not directly from the Company or any Affiliate of the Company) for New Securities.

"Final Memorandum" shall have the meaning set forth in the Purchase Agreement.

"Holder" shall have the meaning set forth in the preamble hereto.

"Initial Placement" shall have the meaning set forth in the preamble hereto.

"Initial Purchaser" shall have the meaning set forth in the preamble hereto.

"Losses" shall have the meaning set forth in Section 6(d) hereof.

"Majority Holders" shall mean the Holders of a majority of the aggregate principal amount of Securities registered under a Registration Statement.

"Managing Underwriters" shall mean the investment banker or investment bankers and manager or managers that shall administer an underwritten offering of the Securities offered pursuant to a Shelf Registration Statement.

"Mortgage" shall mean the Company's Mortgage relating to the Securities, dated as of July 1, 1923, as amended and supplemented through the date hereof, including by the Supplemental Indenture dated as of March 1, 2002 from the Company to BNY Midwest Trust Company, as trustee, and D.G. Donovan, as co-trustee, as the same may be further amended from time to time in accordance with the terms thereof.

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"New Securities" shall mean debt securities of the Company identical in all material respects to the Securities (except that the interest rate step-up provisions and the transfer restrictions shall be modified or eliminated, as appropriate) and to be issued under the Mortgage.

"Prospectus" shall mean the prospectus included in any Registration Statement (including, without limitation, a prospectus that discloses information previously omitted from a prospectus filed as part of an effective registration statement in reliance upon Rule 430A under the Act), as amended or supplemented by any prospectus supplement, with respect to the terms of the offering of any portion of the Securities or the New Securities covered by such Registration Statement, and all amendments and supplements thereto and all material incorporated by reference therein.

"Purchase Agreement" shall have the meaning set forth in the preamble hereto.

"Registered Exchange Offer" shall mean the proposed offer of the Company to issue and deliver to the Holders of the Securities that are not prohibited by any law or policy of the Commission from participating in such offer, in exchange for the Securities, a like aggregate principal amount of the New Securities.

"Registration Statement" shall mean any Exchange Offer Registration Statement or Shelf Registration Statement that covers any of the Securities or the New Securities pursuant to the provisions of this Agreement, any amendments and supplements to such registration statement, including post-effective amendments (in each case including the Prospectus contained therein), all exhibits thereto and all material incorporated by reference therein.

"Securities" shall have the meaning set forth in the preamble hereto.

"Shelf Registration" shall mean a registration effected pursuant to
Section 3 hereof.

"Shelf Registration Period" has the meaning set forth in Section 3(b) hereof.

"Shelf Registration Statement" shall mean a "shelf" registration statement of the Company pursuant to the provisions of Section 3 hereof which covers some or all of the Securities or New Securities, as applicable, on an appropriate form under Rule 415 under the Act, or any similar rule that may be adopted by the Commission, amendments and supplements to such registration statement, including post-effective amendments, in each case including the Prospectus contained therein, all exhibits thereto and all material incorporated by reference therein.

"Trustee" shall mean the corporate trustee with respect to the Securities under the Mortgage.

"Underwriter" shall mean any underwriter of Securities in connection with an offering thereof under a Shelf Registration Statement.

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2. REGISTERED EXCHANGE OFFER.

(a) To the extent not prohibited by any applicable law or applicable interpretation of the Staff of the Commission, the Company shall use its best efforts to consummate the Registered Exchange Offer within 270 days of the date of the original issuance of the Securities (or if such 270th day is not a Business Day, the next succeeding Business Day).

(b) Upon the effectiveness of the Exchange Offer Registration Statement, the Company shall promptly commence the Registered Exchange Offer, it being the objective of such Registered Exchange Offer to enable each Holder electing to exchange Securities for New Securities (assuming that such Holder is not an Affiliate of the Company, acquires the New Securities in the ordinary course of such Holder's business, has no arrangements with any Person to participate in the distribution of the New Securities and is not prohibited by any law or policy of the Commission from participating in the Registered Exchange Offer) to trade such New Securities from and after their receipt without any limitations or restrictions under the Act and without material restrictions under the securities laws of a substantial proportion of the several states of the United States.

(c) In connection with the Registered Exchange Offer, the Company shall:

(i) mail to each Holder a copy of the Prospectus forming part of the Exchange Offer Registration Statement, together with an appropriate letter of transmittal and related documents;

(ii) keep the Registered Exchange Offer open for not less than 20 Business Days and not more than 30 Business Days after the date notice thereof is mailed to the Holders (or, in each case, longer if required by applicable law);

(iii) use its best efforts to keep the Exchange Offer Registration Statement continuously effective under the Act, supplemented and amended as required, under the Act to ensure that it is available for sales of New Securities by Exchanging Dealers during the Exchange Offer Registration Period;

(iv) utilize the services of a depositary for the Registered Exchange Offer with an address in the Borough of Manhattan in New York City, which may be the Trustee or an Affiliate of the Trustee;

(v) permit Holders to withdraw tendered Securities at any time prior to the close of business, New York time, on the last Business Day on which the Registered Exchange Offer is open;

(vi) prior to effectiveness of the Exchange Offer Registration Statement, provide a supplemental letter to the Commission (A) stating that the Company is conducting the Registered Exchange Offer in reliance on the position of the Commission in EXXON CAPITAL HOLDINGS CORPORATION (pub. avail. May 13, 1988), and MORGAN STANLEY AND CO., INC. (pub. avail. June 5, 1991); and (B) including a representation that the Company has not entered into any arrangement or understanding with any Person to distribute the New Securities to be received

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in the Registered Exchange Offer and that, to the best of the Company's information and belief, each Holder participating in the Registered Exchange Offer is acquiring the New Securities in the ordinary course of business and has no arrangement or understanding with any Person to participate in the distribution of the New Securities; and

(vii) comply in all respects with all applicable laws.

(d) As soon as practicable after the close of the Registered Exchange Offer, the Company shall:

(i) accept for exchange all Securities tendered and not validly withdrawn pursuant to the Registered Exchange Offer;

(ii) deliver to the Trustee for cancellation in accordance with
Section 4(s) all Securities so accepted for exchange; and

(iii) cause the Trustee promptly to authenticate and deliver to each Holder of Securities a principal amount of New Securities equal to the principal amount of the Securities of such Holder so accepted for exchange.

(e) Each Holder hereby acknowledges and agrees that any Broker-Dealer and any such Holder using the Registered Exchange Offer to participate in a distribution of the New Securities (x) could not under Commission policy as in effect on the date of this Agreement rely on the position of the Commission in MORGAN STANLEY AND CO., INC. (pub. avail. June 5, 1991) and EXXON CAPITAL HOLDINGS CORPORATION (pub. avail. May 13, 1988), as interpreted in the Commission's letter to SHEARMAN & STERLING dated July 2, 1993 and similar no-action letters; (y) must comply with the registration and prospectus delivery requirements of the Act in connection with any secondary resale transaction; and
(z) must be covered by an effective registration statement containing the selling security holder information required by Item 507 or 508, as applicable, of Regulation S-K under the Act if the resales are of New Securities obtained by such Holder in exchange for Securities acquired by such Holder directly from the Company or one of its Affiliates. Accordingly, each Holder participating in the Registered Exchange Offer shall be required to represent to the Company that, at the time of the consummation of the Registered Exchange Offer:

(i) any New Securities received by such Holder will be acquired in the ordinary course of business;

(ii) such Holder will have no arrangement or understanding with any Person to participate in the distribution of the Securities or the New Securities within the meaning of the Act; and

(iii) such Holder is not an Affiliate of the Company.

(f) If any Initial Purchaser determines that it is not eligible to participate in the Registered Exchange Offer with respect to the exchange of Securities constituting any portion of an unsold allotment, at the request of such Initial Purchaser, the Company shall issue

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and deliver to such Initial Purchaser or the Person purchasing New Securities registered under a Shelf Registration Statement as contemplated by Section 3 hereof from such Initial Purchaser, in exchange for such Securities, a like principal amount of New Securities. The Company shall use its best efforts to cause the CUSIP Service Bureau to issue the same CUSIP number for such New Securities as for New Securities issued pursuant to the Registered Exchange Offer.

3. SHELF REGISTRATION.

(a) If (i) due to any change in law or applicable interpretations thereof by the Commission's staff, the Company determines upon advice of its outside counsel that it is not permitted to effect the Registered Exchange Offer as contemplated by Section 2 hereof;

(ii) for any other reason the Registered Exchange Offer is not consummated within 270 days of the date hereof;

(iii) any Initial Purchaser so requests with respect to Securities that are not eligible to be exchanged for New Securities in the Registered Exchange Offer and that are held by it following consummation of the Registered Exchange Offer;

(iv) any Holder (other than an Initial Purchaser) is not eligible to participate in the Registered Exchange Offer; or

(v) in the case of any Initial Purchaser that participates in the Registered Exchange Offer or acquires New Securities pursuant to
Section 2(f) hereof, such Initial Purchaser does not receive freely tradeable New Securities in exchange for Securities constituting any portion of an unsold allotment (it being understood that (x) the requirement that an Initial Purchaser deliver a Prospectus containing the information required by Item 507 or 508 of Regulation S-K under the Act in connection with sales of New Securities acquired in exchange for such Securities shall result in such New Securities being not "freely tradeable"; and (y) the requirement that an Exchanging Dealer deliver a Prospectus in connection with sales of New Securities acquired in the Registered Exchange Offer in exchange for Securities acquired as a result of market-making activities or other trading activities shall not result in such New Securities being not "freely tradeable"), the Company shall effect a Shelf Registration Statement in accordance with subsection (b) below.

(b) (i) To the extent not prohibited by any applicable law or applicable interpretation of the Staff of the Commission, the Company shall as promptly as practicable (but in no event more than 60 days after so required or requested pursuant to this Section 3), file with the Commission and thereafter shall use its best efforts to cause to be declared effective under the Act a Shelf Registration Statement relating to the offer and sale of the Securities or the New Securities, as applicable, by the Holders thereof from time to time in accordance with the methods of distribution elected by such Holders and set forth in such Shelf Registration Statement; PROVIDED, HOWEVER, that no Holder (other than an Initial Purchaser) shall be entitled to have the Securities held by it covered by such Shelf Registration Statement unless such Holder agrees in writing to be bound by all of the provisions of this Agreement applicable to such

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Holder; and provided further, that with respect to New Securities received by an Initial Purchaser in exchange for Securities constituting any portion of an unsold allotment, the Company may, if permitted by current interpretations by the Commission's staff, file a post-effective amendment to the Exchange Offer Registration Statement containing the information required by Item 507 or 508 of Regulation S-K, as applicable, in satisfaction of its obligations under this subsection with respect thereto, and any such Exchange Offer Registration Statement, as so amended, shall be referred to herein as, and governed by the provisions herein applicable to, a Shelf Registration Statement.

(ii) The Company shall use its best efforts to keep the Shelf Registration Statement continuously effective, supplemented and amended as required by the Act, in order to permit the Prospectus forming part thereof to be usable by Holders for a period of two years from the date the Shelf Registration Statement is declared effective by the Commission or such shorter period that will terminate when all the Securities or New Securities, as applicable, covered by the Shelf Registration Statement have been sold pursuant to the Shelf Registration Statement (in any such case, such period being called the "Shelf Registration Period"). The Company shall be deemed not to have used its best efforts to keep the Shelf Registration Statement effective during the requisite period if it voluntarily takes any action that would result in Holders of Securities covered thereby not being able to offer and sell such Securities during that period, unless (A) such action is required by applicable law; or (B) such action is taken by the Company in good faith and for valid business reasons (not including avoidance of the Company's obligations hereunder), including the acquisition or divestiture of assets, business combinations or similar significant corporate transactions involving the Company or Exelon Corporation so long as the Company promptly thereafter complies with the requirements of Section 4(j) hereof, if applicable.

4. ADDITIONAL REGISTRATION PROCEDURES. In connection with any Shelf Registration Statement and, to the extent applicable, any Exchange Offer Registration Statement, the following provisions shall apply.

(a) The Company shall:

(i) furnish to you, not less than five Business Days prior to the filing thereof with the Commission, a copy of any Exchange Offer Registration Statement and any Shelf Registration Statement, and each amendment thereof and each amendment or supplement, if any, to the Prospectus included therein (including all documents incorporated by reference therein after the initial filing) and shall use its best efforts to reflect in each such document, when so filed with the Commission, such comments as you reasonably propose;

(ii) include the information set forth in Annex A hereto on the facing page of the Exchange Offer Registration Statement, in Annex B hereto in the forepart of the Exchange Offer Registration Statement in a section setting forth details of the Exchange Offer, in Annex C hereto in the underwriting or plan of distribution section of the Prospectus contained in the Exchange Offer

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Registration Statement, and in Annex D hereto in the letter of transmittal delivered pursuant to the Registered Exchange Offer;

(iii) if requested by an Initial Purchaser, include the information required by Item 507 or 508 of Regulation S-K, as applicable, in the Prospectus contained in the Exchange Offer Registration Statement or Shelf Registration Statement; and

(iv) in the case of a Shelf Registration Statement, include the names of the Holders that propose to sell Securities pursuant to the Shelf Registration Statement as selling security holders.

(b) The Company shall advise you, the Holders of Securities covered by any Shelf Registration Statement and any Exchanging Dealer under any Exchange Offer Registration Statement that has provided in writing to the Company a telephone or facsimile number and address for notices, and, if requested by you or any such Holder or Exchanging Dealer, shall confirm such advice in writing (which notice pursuant to clauses (ii)-(v) hereof shall be accompanied by an instruction to suspend the use of the Prospectus until the Company shall have remedied the basis for such suspension):

(i) when a Registration Statement and any amendment thereto has been filed with the Commission and when the Registration Statement or any post-effective amendment thereto has become effective;

(ii) of any request by the Commission for any amendment or supplement to the Registration Statement or the Prospectus or for additional information;

(iii) of the issuance by the Commission of any stop order suspending the effectiveness of the Registration Statement or the initiation of any proceedings for that purpose;

(iv) of the receipt by the Company of any notification with respect to the suspension of the qualification of the securities included therein for sale in any jurisdiction or the initiation of any proceeding for such purpose; and

(v) of the happening of any event that requires any change in the Registration Statement or the Prospectus so that, as of such date, the statements therein are not misleading and do not omit to state a material fact required to be stated therein or necessary to make the statements therein (in the case of the Prospectus, in the light of the circumstances under which they were made) not misleading.

(c) The Company shall use its best efforts to obtain the withdrawal of any order suspending the effectiveness of any Registration Statement or the qualification of the securities therein for sale in any jurisdiction at the earliest possible time.

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(d) The Company shall furnish to each Holder of Securities covered by any Shelf Registration Statement, without charge, at least one copy of such Shelf Registration Statement and any post-effective amendment thereto, including all material incorporated therein by reference, and, if the Holder so requests in writing, all exhibits thereto (including exhibits incorporated by reference therein).

(e) The Company shall, during the Shelf Registration Period, deliver to each Holder of Securities covered by any Shelf Registration Statement, without charge, as many copies of the Prospectus (including each preliminary Prospectus) included in such Shelf Registration Statement and any amendment or supplement thereto as such Holder may reasonably request. The Company consents to the use of the Prospectus or any amendment or supplement thereto by each of the selling Holders of Securities in connection with the offering and sale of the Securities covered by the Prospectus, or any amendment or supplement thereto, included in the Shelf Registration Statement.

(f) The Company shall furnish to each Exchanging Dealer which so requests, without charge, at least one copy of the Exchange Offer Registration Statement and any post-effective amendment thereto, including all material incorporated by reference therein, and, if the Exchanging Dealer so requests in writing, all exhibits thereto (including exhibits incorporated by reference therein).

(g) The Company shall promptly deliver to each Initial Purchaser, each Exchanging Dealer and each other Person required to deliver a Prospectus during the Exchange Offer Registration Period, without charge, as many copies of the Prospectus included in such Exchange Offer Registration Statement and any amendment or supplement thereto as any such Person may reasonably request. The Company consents to the use of the Prospectus or any amendment or supplement thereto by any Initial Purchaser, any Exchanging Dealer and any such other Person that may be required to deliver a Prospectus following the Registered Exchange Offer in connection with the offering and sale of the New Securities covered by the Prospectus, or any amendment or supplement thereto, included in the Exchange Offer Registration Statement.

(h) Prior to the Registered Exchange Offer or any other offering of Securities pursuant to any Registration Statement, the Company shall arrange, if necessary, for the qualification of the Securities or the New Securities for sale under the laws of such jurisdictions as any Holder shall reasonably request and will maintain such qualification in effect so long as required; provided that in no event shall the Company be obligated to qualify to do business in any jurisdiction where it is not then so qualified or to take any action that would subject it to service of process in suits, other than those arising out of the Initial Placement, the Registered Exchange Offer or any offering pursuant to a Shelf Registration Statement, in any such jurisdiction where it is not then so subject.

(i) The Company shall cooperate with the Holders of Securities to facilitate the timely preparation and delivery of certificates representing New Securities or Securities to be issued or sold pursuant to any Registration Statement free of any restrictive legends and in such denominations and registered in such names as Holders may request.

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(j) Upon the occurrence of any event contemplated by subsections
(b)(ii) through (v) above, the Company shall promptly prepare a post-effective amendment to the applicable Registration Statement or an amendment or supplement to the related Prospectus or file any other required document so that, as thereafter delivered to Initial Purchasers of the Securities included therein, the Prospectus will not include an untrue statement of a material fact or omit to state any material fact necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading. In such circumstances, the period of effectiveness of the Exchange Offer Registration Statement provided for in Section 2 and the Shelf Registration Statement provided for in Section 3(b) shall each be extended by the number of days from and including the date of the giving of a notice of suspension pursuant to
Section 4(b) to and including the date when the Initial Purchasers, the Holders of the Securities and any known Exchanging Dealer shall have received such amended or supplemented Prospectus pursuant to this Section.

(k) Not later than the effective date of any Registration Statement, the Company shall provide a CUSIP number for the Securities or the New Securities, as the case may be, registered under such Registration Statement and provide the Trustee with certificates for such Securities or New Securities, in a form eligible for deposit with The Depository Trust Company.

(l) The Company shall make generally available to its security holders as soon as practicable after the effective date of the applicable Registration Statement an earnings statement satisfying the provisions of
Section 11(a) of the Act.

(m) The Company shall cause the Mortgage to be qualified under the Trust Indenture Act in a timely manner.

(n) The Company may require each Holder of Securities to be sold pursuant to any Shelf Registration Statement to furnish to the Company such information regarding the Holder and the distribution of such Securities as the Company may from time to time reasonably require for inclusion in such Registration Statement. The Company may exclude from such Shelf Registration Statement the Securities of any Holder that unreasonably fails to furnish such information within a reasonable time after receiving such request and the Company shall be under no further obligations to such Holder to include such Holder in a Shelf Registration Statement.

(o) In the case of any Shelf Registration Statement, the Company shall enter into such and take all other appropriate actions (including if requested an underwriting agreement in customary form) in order to expedite or facilitate the registration or the disposition of the Securities, and in connection therewith, if an underwriting agreement is entered into, cause the same to contain indemnification provisions and procedures no less favorable than those set forth in Section 6 (or such other provisions and procedures acceptable to the Majority Holders and the Managing Underwriters, if any, with respect to all parties to be indemnified pursuant to Section 6.

(p) In the case of any Shelf Registration Statement, the Company shall:

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(i) subject to execution of a confidentiality agreement in form and substance reasonably acceptable to the Company and the Holders, make reasonably available for inspection by the Holders of Securities to be registered thereunder, any underwriter participating in any disposition pursuant to such Registration Statement, and any attorney, accountant or other agent retained by the Holders or any such underwriter all relevant financial and other records, pertinent corporate documents and properties of the Company and its subsidiaries;

(ii) cause the Company's officers, directors and employees to supply all relevant information reasonably requested by the Holders or any such underwriter, attorney, accountant or agent in connection with any such Registration Statement as is customary for similar due diligence examinations; provided, however, that any information that is designated in writing by the Company, in good faith, as confidential at the time of delivery of such information shall be kept confidential by the Holders or any such underwriter, attorney, accountant or agent, unless such disclosure is made in connection with a court proceeding or required by law, or such information becomes available to the public generally or through a third party without an accompanying obligation of confidentiality;

(iii) make such representations and warranties to the Holders of Securities registered thereunder and the underwriters, if any, in form, substance and scope as are customarily made by issuers to underwriters in underwritten offerings and covering those matters set forth in the Purchase Agreement;

(iv) obtain opinions of counsel to the Company and updates thereof (which counsel and opinions (in form, scope and substance) shall be reasonably satisfactory to the Managing Underwriters, if any) addressed to each selling Holder and the underwriters, if any, covering the matters covered in the opinion delivered under the Purchase Agreement and matters related to registration of the Securities under the Act and the qualification of the Mortgage under the Trust Indenture Act of 1940, as amended;

(v) obtain "cold comfort" letters and updates thereof from the independent certified public accountants of the Company (and, if necessary, any other independent certified public accountants of any subsidiary of the Company or of any business acquired by the Company for which financial statements and financial data are, or are required to be, included in the Registration Statement), addressed to each selling Holder of Securities registered thereunder and the underwriters, if any, in customary form and covering matters of the type customarily covered in "cold comfort" letters in connection with primary underwritten offerings; and

(vi) deliver such documents and certificates as may be reasonably requested by the Majority Holders and the Managing Underwriters, if any, including those to evidence compliance with
Section 4(k) and with any customary

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conditions contained in the underwriting agreement or other agreement entered into by the Company.

The actions set forth in clauses (iii), (iv), (v) and (vi) of this Section shall be performed at each closing under any underwriting or similar agreement as and to the extent required thereunder.

(q) If a Registered Exchange Offer is to be consummated, upon delivery of the Securities by Holders to the Company (or to such other Person as directed by the Company) in exchange for the New Securities, the Company shall mark, or caused to be marked, on the Securities so exchanged that such Securities are being canceled in exchange for the New Securities. In no event shall the Securities be marked as paid or otherwise satisfied.

(r) The Company will use its best efforts (i) if the Securities have been rated prior to the initial sale of such Securities pursuant to the Purchase Agreement, to confirm such ratings will apply to the Securities or the New Securities, as the case may be, covered by a Registration Statement; or (ii) if the Securities were not previously rated, to cause the Securities covered by a Registration Statement to be rated with at least one nationally recognized statistical rating agency, if so requested by Majority Holders with respect to the related Registration Statement or by any Managing Underwriters.

(s) In the event that any Broker-Dealer shall underwrite any Securities or participate as a member of an underwriting syndicate or selling group or "assist in the distribution" (within the meaning of the Rules of Fair Practice and the By-Laws of the National Association of Securities Dealers, Inc.) thereof, whether as a Holder of such Securities or as an underwriter, a placement or sales agent or a broker or dealer in respect thereof, or otherwise, assist such Broker-Dealer in complying with the requirements of such Rules and By-Laws, including, without limitation, by:

(i) if such Rules or By-Laws shall so require, engaging a "qualified independent underwriter" (as defined in such Rules) to participate in the preparation of the Registration Statement, to exercise usual standards of due diligence with respect thereto and, if any portion of the offering contemplated by such Registration Statement is an underwritten offering or is made through a placement or sales agent, to recommend the yield of such Securities;

(ii) indemnifying any such qualified independent underwriter to the extent of the indemnification of underwriters provided in Section 6 hereof; and

(iii) providing such information to such Broker-Dealer as may be required in order for such Broker-Dealer to comply with the requirements of such Rules.

(t) The Company shall use its best efforts to take all other steps necessary to effect the registration of the Securities or the New Securities, as the case may be, covered by a Registration Statement.

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5. REGISTRATION EXPENSES. The Company shall bear all expenses incurred in connection with the performance of its obligations under Sections 2, 3 and 4 hereof and, in the event of any Shelf Registration Statement, will reimburse the Holders for the reasonable fees and disbursements of one firm or counsel designated by the Majority Holders to act as counsel for the Holders in connection therewith, and, in the case of any Exchange Offer Registration Statement, will reimburse the Initial Purchasers for the reasonable fees and disbursements of their counsel incurred in connection with their review of the Exchange Offer Registration Statement.

6. INDEMNIFICATION AND CONTRIBUTION.

(a) The Company agrees to indemnify and hold harmless each Holder of Securities or New Securities, as the case may be, covered by any Registration Statement (including each Initial Purchaser and, with respect to any Prospectus delivery as contemplated in Section 4(h) hereof, each Exchanging Dealer), the directors, officers, employees and agents of each such Holder and each Person who controls any such Holder within the meaning of either the Act or the Exchange Act against any and all losses, claims, damages or liabilities, joint or several, to which they or any of them may become subject under the Act, the Exchange Act or other Federal or state statutory law or regulation, at common law or otherwise, insofar as such losses, claims, damages or liabilities (or actions in respect thereof) arise out of or are based upon any untrue statement or alleged untrue statement of a material fact contained in the Registration Statement as originally filed or in any amendment thereof, or in any preliminary Prospectus or the Prospectus, or in any amendment thereof or supplement thereto, or arise out of or are based upon the omission or alleged omission to state therein a material fact required to be stated therein or necessary to make the statements therein not misleading, and agrees to reimburse each such indemnified party, as incurred, for any legal or other expenses reasonably incurred by them in connection with investigating or defending any such loss, claim, damage, liability or action; provided, however, that the Company will not be liable in any case to the extent that any such loss, claim, damage or liability arises out of or is based upon any such untrue statement or alleged untrue statement or omission or alleged omission made therein in reliance upon and in conformity with written information furnished to the Company by or on behalf of any such Holder specifically for inclusion therein; provided, further, that such indemnity with respect to any untrue statement contained in or omission from the preliminary Prospectus shall not inure to the benefit of any Holder (or any person controlling such holder) from whom the person asserting such loss, claim, damage or liability purchased any of the Securities or New Securities which are the subject thereof if such person did not receive a copy of the Prospectus (or, if the Prospectus shall have been amended or supplemented, the Prospectus as then amended or supplemented), excluding incorporated documents, at or prior to the confirmation of sale of such securities or New Securities to such person in any case where such delivery is required by the Act and the untrue statement or omission of a material fact contained in such preliminary Prospectus was corrected in the Prospectus as then amended or supplemented), and it is finally judicially determined that such delivery was required to be made under the Act and was no so made. This indemnity agreement will be in addition to any liability which the Company may otherwise have.

The Company also agrees to indemnify or contribute as provided in Section 6(d) to Losses of each and any person deemed an "underwriter", under the Act or the rules and regulations thereunder, of Securities or New Securities, as the case may be, registered under a

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Shelf Registration Statement, their directors, officers, employees or agents and each Person who controls such underwriter on substantially the same basis as that of the indemnification of the Initial Purchasers and the selling Holders provided in this Section 6(a) and shall, if requested by any Holder, enter into an underwriting agreement reflecting such agreement, as provided in Section 4(p) hereof.

(b) Each Holder of securities covered by a Registration Statement (including each Initial Purchaser and, with respect to any Prospectus delivery as contemplated in Section 4(h) hereof, each Exchanging Dealer) severally agrees to indemnify and hold harmless the Company each of its directors each of its officers who signs such Registration Statement and each Person who controls the Company within the meaning of either the Act or the Exchange Act, to the same extent as the foregoing indemnity from the Company to each such Holder, but only with reference to written information relating to such Holder furnished to the Company by or on behalf of such Holder specifically for inclusion in the documents referred to in the foregoing indemnity. This indemnity agreement will be in addition to any liability which any such Holder may otherwise have.

(c) Promptly after receipt by an indemnified party under this Section 6 of notice of the commencement of any action, such indemnified party will, if a claim in respect thereof is to be made against the indemnifying party under this Section, notify the indemnifying party in writing of the commencement thereof; but the failure so to notify the indemnifying party (i) will not relieve it from liability under paragraph (a) or (b) above unless and to the extent it did not otherwise learn of such action and such failure results in the forfeiture by the indemnifying party of substantial rights and defenses; and (ii) will not, in any event, relieve the indemnifying party from any obligations to any indemnified party other than the indemnification obligation provided in paragraph (a) or (b) above. The indemnifying party shall be entitled to appoint counsel of the indemnifying party's choice at the indemnifying party's expense to represent the indemnified party in any action for which indemnification is sought (in which case the indemnifying party shall not thereafter be responsible for the fees and expenses of any separate counsel retained by the indemnified party or parties except as set forth below); provided, however, that such counsel shall be satisfactory to the indemnified party. Notwithstanding the indemnifying party's election to appoint counsel to represent the indemnified party in an action, the indemnified party shall have the right to employ separate counsel, and the indemnifying party shall bear the reasonable fees, costs and expenses of such separate counsel if (i) the use of counsel chosen by the indemnifying party to represent the indemnified party would present such counsel with a conflict of interest; (ii) the actual or potential defendants in, or targets of, any such action include both the indemnified party and the indemnifying party and the indemnified party shall have reasonably concluded that there may be legal defenses available to it and/or other indemnified parties which are different from or additional to those available to the indemnifying party; (iii) the indemnifying party shall not have employed counsel satisfactory to the indemnified party to represent the indemnified party within a reasonable time after notice of the institution of such action; or (iv) the indemnifying party shall authorize the indemnified party to employ separate counsel at the expense of the indemnifying party; provided, however, that the indemnifying party shall not be responsible for the fees and expenses of more than one separate firm representing indemnified parties described in clauses (i) or (ii) of this sentence. An indemnifying party will not, without the prior written consent of the indemnified parties, settle or compromise or consent to the entry of any judgment with respect to any pending or threatened

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claim, action, suit or proceeding in respect of which indemnification or contribution may be sought hereunder (whether or not the indemnified parties are actual or potential parties to such claim or action) unless such settlement, compromise or consent includes an unconditional release of each indemnified party from all liability arising out of such claim, action, suit or proceeding.

(d) In the event that the indemnity provided in paragraph (a) or (b) of this Section is for any reason held to be unenforceable by an indemnified party although applicable in accordance with its terms, then each applicable indemnifying party shall have a several and not joint obligation to contribute to the aggregate losses, claims, damages and liabilities (including legal or other expenses reasonably incurred in connection with investigating or defending same) (collectively "Losses") to which such indemnified party may be subject in such proportion as is appropriate to reflect the relative benefits received by such indemnifying party, on the one hand, and such indemnified party, on the other hand, from the Initial Placement and the Registration Statement which resulted in such Losses; provided, however, that in no case shall any Initial Purchaser or any subsequent Holder of any Security or New Security be responsible, in the aggregate, for any amount in excess of the purchase discount or commission applicable to such Security, or in the case of a New Security, applicable to the Security that was exchangeable into such New Security, as set forth on the cover page of the Final Memorandum, nor shall any underwriter be responsible for any amount in excess of the underwriting discount or commission applicable to the securities purchased by such underwriter under the Registration Statement which resulted in such Losses. If the allocation provided by the immediately preceding sentence is unavailable for any reason, the indemnifying party and the indemnified party shall contribute in such proportion as is appropriate to reflect not only such relative benefits but also the relative fault of such indemnifying party, on the one hand, and such indemnified party, on the other hand, in connection with the statements or omissions which resulted in such Losses as well as any other relevant equitable considerations. Benefits received by the Company shall be deemed to be equal to the sum of (x) the total net proceeds from the Initial Placement (before deducting expenses) as set forth on the cover page of the Final Memorandum and (y) the total amount of additional interest which the Company was not required to pay as a result of registering the securities covered by the Registration Statement which resulted in such Losses. Benefits received by the Initial Purchasers shall be deemed to be equal to the total purchase discounts and commissions as set forth on the cover page of the Final Memorandum, and benefits received by any other Holders shall be deemed to be equal to the value of receiving Securities or New Securities, as applicable, registered under the Act. Benefits received by any underwriter shall be deemed to be equal to the total underwriting discounts and commissions, as set forth on the cover page of the Prospectus forming a part of the Registration Statement which resulted in such Losses. Relative fault shall be determined by reference to, among other things, whether any alleged untrue statement or omission relates to information provided by the indemnifying party, on the one hand, or by the indemnified party, on the other hand, the intent of the parties and their relative knowledge, access to information and opportunity to correct or prevent such untrue statement or omission. The parties agree that it would not be just and equitable if contribution were determined by pro rata allocation (even if the Holders were treated as one entity for such purpose) or any other method of allocation which does not take account of the equitable considerations referred to above. Notwithstanding the provisions of this paragraph (d), no Person guilty of fraudulent misrepresentation (within the meaning of Section 11(f) of the Act) shall be entitled to contribution from any Person who was not guilty of such fraudulent misrepresentation. For purposes of this Section, each Person who controls a Holder within the

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meaning of either the Act or the Exchange Act and each director, officer, employee and agent of such Holder shall have the same rights to contribution as such Holder, and each Person who controls the Company within the meaning of either the Act or the Exchange Act, each officer of the Company who shall have signed the Registration Statement and each director of the Company shall have the same rights to contribution as the Company, subject in each case to the applicable terms and conditions of this paragraph (d).

(e) The provisions of this Section will remain in full force and effect, regardless of any investigation made by or on behalf of any Holder or the Company or any of the officers, directors or controlling Persons referred to in this Section hereof, and will survive the sale by a Holder of securities covered by a Registration Statement.

7. UNDERWRITTEN REGISTRATIONS.

(a) If any of the Securities or New Securities, as the case may be, covered by any Shelf Registration Statement are to be sold in an underwritten offering, the Managing Underwriters shall be selected by the Majority Holders.

(b) No Person may participate in any underwritten offering pursuant to any Shelf Registration Statement, unless such Person (i) agrees to sell such Person's Securities or New Securities, as the case may be, on the basis reasonably provided in any underwriting arrangements approved by the Persons entitled hereunder to approve such arrangements; and (ii) completes and executes all questionnaires, powers of attorney, indemnities, underwriting agreements and other documents reasonably required under the terms of such underwriting arrangements.

8. NO INCONSISTENT AGREEMENTS. The Company has not, as of the date hereof, entered into, nor shall it, on or after the date hereof, enter into, any agreement with respect to its securities that is inconsistent with the rights granted to the Holders herein or otherwise conflicts with the provisions hereof.

9. AMENDMENTS AND WAIVERS. The provisions of this Agreement, including the provisions of this sentence, may not be amended, qualified, modified or supplemented, and waivers or consents to departures from the provisions hereof may not be given, unless the Company has obtained the written consent of the Majority Holders (or, after the consummation of any Registered Exchange Offer in accordance with Section 2 hereof, of New Securities); provided that, with respect to any matter that directly or indirectly affects the rights of any Initial Purchaser hereunder, the Company shall obtain the written consent of each such Initial Purchaser against which such amendment, qualification, supplement, waiver or consent is to be effective. Notwithstanding the foregoing (except the foregoing proviso), a waiver or consent to departure from the provisions hereof with respect to a matter that relates exclusively to the rights of Holders whose Securities or New Securities, as the case may be, are being sold pursuant to a Registration Statement and that does not directly or indirectly affect the rights of other Holders may be given by the Majority Holders, determined on the basis of Securities or New Securities, as the case may be, being sold rather than registered under such Registration Statement.

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10. NOTICES. All notices and other communications provided for or permitted hereunder shall be made in writing by hand-delivery, first-class mail, telex, telecopier or air courier guaranteeing overnight delivery:

(a) if to a Holder, at the most current address given by such holder to the Company in accordance with the provisions of this Section, which address initially is, with respect to each Holder, the address of such Holder maintained by the Registrar under the Mortgage, with a copy in like manner to Salomon Smith Barney Inc. at its address set forth in the Purchase Agreement;

(b) if to you, initially at the respective addresses set forth in the Purchase Agreement; and

(c) if to the Company, initially at its address set forth in the Purchase Agreement.

All such notices and communications shall be deemed to have been duly given when received.

The Initial Purchasers or the Company by notice to the other parties may designate additional or different addresses for subsequent notices or communications.

11. SUCCESSORS. This Agreement shall inure to the benefit of and be binding upon the successors and assigns of each of the parties, including, without the need for an express assignment or any consent by the Company thereto, subsequent Holders of Securities and the New Securities. The Company hereby agrees to extend the benefits of this Agreement to any Holder of Securities and the New Securities, and any such Holder may specifically enforce the provisions of this Agreement as if an original party hereto.

12. COUNTERPARTS. This agreement may be in signed counterparts, each of which shall an original and all of which together shall constitute one and the same agreement.

13. HEADINGS. The headings used herein are for convenience only and shall not affect the construction hereof.

14. APPLICABLE LAW. This Agreement shall be governed by and construed in accordance with the laws of the State of New York applicable to contracts made and to be performed in the State of New York.

15. SEVERABILITY. In the event that any one of more of the provisions contained herein, or the application thereof in any circumstances, is held invalid, illegal or unenforceable in any respect for any reason, the validity, legality and enforceability of any such provision in every other respect and of the remaining provisions hereof shall not be in any way impaired or affected thereby, it being intended that all of the rights and privileges of the parties shall be enforceable to the fullest extent permitted by law.

16. SECURITIES HELD BY THE COMPANY, ETC. Whenever the consent or approval of Holders of a specified percentage of principal amount of Securities or New Securities is required

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hereunder, Securities or New Securities, as applicable, held by the Company or its Affiliates (other than subsequent Holders of Securities or New Securities if such subsequent Holders are deemed to be Affiliates solely by reason of their holdings of such Securities or New Securities) shall not be counted in determining whether such consent or approval was given by the Holders of such required percentage.

[signature page follows]

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If the foregoing is in accordance with your understanding of our agreement, please sign and return to us the enclosed duplicate hereof, whereupon this letter and your acceptance shall represent a binding agreement among the Company and the several Initial Purchasers.

Very truly yours,

COMMONWEALTH EDISON COMPANY

By:

Name:
Title:

The foregoing Agreement is hereby confirmed and accepted as of the date first above written.

SALOMON SMITH BARNEY INC.
J.P. MORGAN SECURITIES INC.

By: SALOMON SMITH BARNEY INC.

By:
Name:
Title:

For themselves and the other
several Initial Purchasers
named in Schedule I to the
Purchase Agreement.

ANNEX A

Each Broker-Dealer that receives New Securities for its own account pursuant to the Exchange Offer must acknowledge that it will deliver a prospectus in connection with any resale of such New Securities. The Letter of Transmittal states that by so acknowledging and by delivering a prospectus, a Broker-Dealer will not be deemed to admit that it is an "underwriter" within the meaning of the Securities Act. This Prospectus, as it may be amended or supplemented from time to time, may be used by a Broker-Dealer in connection with resales of New Securities received in exchange for Securities where such Securities were acquired by such Broker-Dealer as a result of market-making activities or other trading activities. The Company has agreed that, starting on the Expiration Date (as defined herein) and ending on the close of business one year after the Expiration Date, it will make this Prospectus available to any Broker-Dealer for use in connection with any such resale. See "Plan of Distribution".

ANNEX B

Each Broker-Dealer that receives New Securities for its own account in exchange for Securities, where such Securities were acquired by such Broker-Dealer as a result of market-making activities or other trading activities, must acknowledge that it will deliver a prospectus in connection with any resale of such New Securities. See "Plan of Distribution".

ANNEX C

PLAN OF DISTRIBUTION

Each Broker-Dealer that receives New Securities for its own account pursuant to the Exchange Offer must acknowledge that it will deliver a prospectus in connection with any resale of such New Securities. This Prospectus, as it may be amended or supplemented from time to time, may be used by a Broker-Dealer in connection with resales of New Securities received in exchange for Securities where such Securities were acquired as a result of market-making activities or other trading activities. The Company has agreed that, starting on the Expiration Date and ending on the close of business one year after the Expiration Date, it will make this Prospectus, as amended or supplemented, available to any Broker-Dealer for use in connection with any such resale. In addition, until __________, 20___, all dealers effecting transactions in the New Securities may be required to deliver a prospectus.

The Company will not receive any proceeds from any sale of New Securities by brokers-dealers. New Securities received by Broker-Dealers for their own account pursuant to the Exchange Offer may be sold from time to time in one or more transactions in the over-the-counter market, in negotiated transactions, through the writing of options on the New Securities or a combination of such methods of resale, at market prices prevailing at the time of resale, at prices related to such prevailing market prices or negotiated prices. Any such resale may be made directly to purchasers or to or through brokers or dealers who may receive compensation in the form of commissions or concessions from any such Broker-Dealer and/or the purchasers of any such New Securities. Any Broker-Dealer that resells New Securities that were received by it for its own account pursuant to the Exchange Offer and any broker or dealer that participates in a distribution of such New Securities may be deemed to be an "underwriter" within the meaning of the Securities Act and any profit of any such resale of New Securities and any commissions or concessions received by any such Persons may be deemed to be underwriting compensation under the Securities Act. The Letter of Transmittal states that by acknowledging that it will deliver and by delivering a prospectus, a Broker-Dealer will not be deemed to admit that it is an "underwriter" within the meaning of the Securities Act.

For a period of one year after the Expiration Date, the Company will promptly send additional copies of this Prospectus and any amendment or supplement to this Prospectus to any Broker-Dealer that requests such documents in the Letter of Transmittal. The Company has agreed to pay all expenses incident to the Exchange Offer (including the expenses of one counsel for the holder of the Securities) other than commissions or concessions of any brokers or dealers and will indemnify the holders of the Securities (including any Broker-Dealers) against certain liabilities, including liabilities under the Securities Act.

ANNEX D

RIDER A

CHECK HERE IF YOU ARE A BROKER-DEALER AND WISH TO RECEIVE 10 ADDITIONAL COPIES OF THE PROSPECTUS AND 10 COPIES OF ANY AMENDMENTS OR SUPPLEMENTS THERETO. 

Name:       _________________________________
Address:    _________________________________
            _________________________________

RIDER B

If the undersigned is not a Broker-Dealer, the undersigned represents that it acquired the New Securities in the ordinary course of its business, it is not engaged in, and does not intend to engage in, a distribution of New Securities and it has not arrangements or understandings with any Person to participate in a distribution of the New Securities. If the undersigned is a Broker-Dealer that will receive New Securities for its own account in exchange for Securities, it represents that the Securities to be exchanged for New Securities were acquired by it as a result of market-making activities or other trading activities and acknowledges that it will deliver a prospectus in connection with any resale of such New Securities; however, by so acknowledging and by delivering a prospectus, the undersigned will not be deemed to admit that it is an "underwriter" within the meaning of the Securities Act.

EXHIBIT 4.5

COMMONWEALTH EDISON COMPANY

$200,000,000

First Mortgage 6.15% Bonds, Series 98 Due 2012

REGISTRATION rights agreement

New York, New York
June 20, 2002

Barclays Capital Inc.
First Union Securities, Inc.
As Representatives of the Initial Purchasers c/o Barclays Capital Inc.
222 Broadway
New York, New York 10038

Ladies and Gentlemen:

Commonwealth Edison Company, a corporation organized under the laws of the State of Illinois (the "Company"), proposes to issue and sell to certain purchasers (the "Initial Purchasers") an additional $200,000,000 (the "Securities") of the Company's outstanding First Mortgage 6.15% Bonds, Series Due 2012 (the "Outstanding Securities"), upon the terms set forth in a purchase agreement dated as of June 13, 2002 (the "Purchase Agreement"), relating to the initial placement of the Securities (the "Initial Placement"). To induce the Initial Purchasers to enter into the Purchase Agreement and to satisfy a condition of your obligations thereunder, the Company agrees with you for your benefit and the benefit of the holders from time to time of the Securities (including the Initial Purchasers) (each a "Holder" and, together, the "Holders"), as follows:

1. DEFINITIONS. Each of the capitalized terms used herein without definition shall have the meaning set forth in the Purchase Agreement. As used in this Agreement, the following capitalized defined terms shall have the following meanings:

"Act" shall mean the Securities Act of 1933, as amended, and the rules and regulations of the Commission promulgated thereunder.

"Affiliate" of any specified Person shall mean any other Person that, directly or indirectly, is in control of, is controlled by, or is under common control with, such specified Person. For purposes of this definition, control of a Person shall mean the power, direct or indirect, to direct or cause the direction of the management and policies of such Person whether by contract or otherwise; and the terms "controlling" and "controlled" shall have meanings correlative to the foregoing.

"Broker-Dealer" shall mean any broker or dealer registered as such under the Exchange Act.

"Business Day" shall mean any day other than a Saturday, a Sunday or a legal holiday or a day on which banking institutions or trust companies are authorized or obligated by law to close in New York City.

"Commission" shall mean the Securities and Exchange Commission.

"Exchange Act" shall mean the Securities Exchange Act of 1934, as amended, and the rules and regulations of the Commission promulgated thereunder.

"Exchange Offer Registration Period" shall mean the one-year period following the consummation of the Registered Exchange Offer, exclusive of any period during which any stop order shall be in effect suspending the effectiveness of the Exchange Offer Registration Statement.

"Exchange Offer Registration Statement" shall mean a registration statement of the Company on an appropriate form under the Act with respect to the Registered Exchange Offer, all amendments and supplements to such registration statement, including post-effective amendments thereto, in each case including the Prospectus contained therein, all exhibits thereto and all material incorporated by reference therein.

"Exchanging Dealer" shall mean any Holder (which may include any Initial Purchaser) that is a Broker-Dealer and elects to exchange for New Securities any Securities that it acquired for its own account as a result of market-making activities or other trading activities (but not directly from the Company or any Affiliate of the Company) for New Securities.

"Final Memorandum" shall have the meaning set forth in the Purchase Agreement.

"Holder" shall have the meaning set forth in the preamble hereto.

"Initial Placement" shall have the meaning set forth in the preamble hereto.

"Initial Purchaser" shall have the meaning set forth in the preamble hereto.

"Losses" shall have the meaning set forth in Section 6(d) hereof.

"Majority Holders" shall mean the Holders of a majority of the aggregate principal amount of Securities registered under a Registration Statement.

"Managing Underwriters" shall mean the investment banker or investment bankers and manager or managers that shall administer an underwritten offering of the Securities offered pursuant to a Shelf Registration Statement.

"Mortgage" shall mean the Company's Mortgage relating to the Securities, dated as of July 1, 1923, as amended and supplemented through the date hereof, including by the Supplemental Indenture dated as of June 1, 2002 from the Company to BNY Midwest Trust Company, as trustee, and D.G. Donovan, as co-trustee, as the same may be further amended from time to time in accordance with the terms thereof.

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"New Securities" shall mean debt securities of the Company identical in all material respects to the Securities (except that the interest rate step-up provisions and the transfer restrictions shall be modified or eliminated, as appropriate) and to be issued under the Mortgage.

"Prospectus" shall mean the prospectus included in any Registration Statement (including, without limitation, a prospectus that discloses information previously omitted from a prospectus filed as part of an effective registration statement in reliance upon Rule 430A under the Act), as amended or supplemented by any prospectus supplement, with respect to the terms of the offering of any portion of the Securities or the New Securities covered by such Registration Statement, and all amendments and supplements thereto and all material incorporated by reference therein.

"Purchase Agreement" shall have the meaning set forth in the preamble hereto.

"Registered Exchange Offer" shall mean the proposed offer of the Company to issue and deliver to the Holders of the Securities that are not prohibited by any law or policy of the Commission from participating in such offer, in exchange for the Securities, a like aggregate principal amount of the New Securities.

"Registration Statement" shall mean any Exchange Offer Registration Statement or Shelf Registration Statement that covers any of the Securities or the New Securities pursuant to the provisions of this Agreement, any amendments and supplements to such registration statement, including post-effective amendments (in each case including the Prospectus contained therein), all exhibits thereto and all material incorporated by reference therein.

"Securities" shall have the meaning set forth in the preamble hereto.

"Shelf Registration" shall mean a registration effected pursuant to
Section 3 hereof.

"Shelf Registration Period" has the meaning set forth in Section 3(b) hereof.

"Shelf Registration Statement" shall mean a "shelf" registration statement of the Company pursuant to the provisions of Section 3 hereof which covers some or all of the Securities or New Securities, as applicable, on an appropriate form under Rule 415 under the Act, or any similar rule that may be adopted by the Commission, amendments and supplements to such registration statement, including post-effective amendments, in each case including the Prospectus contained therein, all exhibits thereto and all material incorporated by reference therein.

"Trustee" shall mean the corporate trustee with respect to the Securities under the Mortgage.

"Underwriter" shall mean any underwriter of Securities in connection with an offering thereof under a Shelf Registration Statement.

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2. REGISTERED EXCHANGE OFFER.

(a) To the extent not prohibited by any applicable law or applicable interpretation of the Staff of the Commission, the Company shall use its best efforts to consummate the Registered Exchange Offer no later than December 8, 2002 (or if such day is not a Business Day, the next succeeding Business Day).

(b) Upon the effectiveness of the Exchange Offer Registration Statement, the Company shall promptly commence the Registered Exchange Offer, it being the objective of such Registered Exchange Offer to enable each Holder electing to exchange Securities for New Securities (assuming that such Holder is not an Affiliate of the Company, acquires the New Securities in the ordinary course of such Holder's business, has no arrangements with any Person to participate in the distribution of the New Securities and is not prohibited by any law or policy of the Commission from participating in the Registered Exchange Offer) to trade such New Securities from and after their receipt without any limitations or restrictions under the Act and without material restrictions under the securities laws of a substantial proportion of the several states of the United States.

(c) In connection with the Registered Exchange Offer, the Company shall:

(i) mail to each Holder a copy of the Prospectus forming part of the Exchange Offer Registration Statement, together with an appropriate letter of transmittal and related documents;

(ii) keep the Registered Exchange Offer open for not less than 20 Business Days and not more than 30 Business Days after the date notice thereof is mailed to the Holders (or, in each case, longer if required by applicable law);

(iii) use its best efforts to keep the Exchange Offer Registration Statement continuously effective under the Act, supplemented and amended as required, under the Act to ensure that it is available for sales of New Securities by Exchanging Dealers during the Exchange Offer Registration Period;

(iv) utilize the services of a depositary for the Registered Exchange Offer with an address in the Borough of Manhattan in New York City, which may be the Trustee or an Affiliate of the Trustee;

(v) permit Holders to withdraw tendered Securities at any time prior to the close of business, New York time, on the last Business Day on which the Registered Exchange Offer is open;

(vi) prior to effectiveness of the Exchange Offer Registration Statement, provide a supplemental letter to the Commission (A) stating that the Company is conducting the Registered Exchange Offer in reliance on the position of the Commission in EXXON CAPITAL HOLDINGS CORPORATION (pub. avail. May 13, 1988), and MORGAN STANLEY AND CO., INC. (pub. avail. June 5, 1991); and (B) including a representation that the Company has not entered into any arrangement or understanding with any Person to distribute the New Securities to be received

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in the Registered Exchange Offer and that, to the best of the Company's information and belief, each Holder participating in the Registered Exchange Offer is acquiring the New Securities in the ordinary course of business and has no arrangement or understanding with any Person to participate in the distribution of the New Securities; and

(vii) comply in all respects with all applicable laws.

(d) As soon as practicable after the close of the Registered Exchange Offer, the Company shall:

(i) accept for exchange all Securities tendered and not validly withdrawn pursuant to the Registered Exchange Offer;

(ii) deliver to the Trustee for cancellation in accordance with
Section 4(s) all Securities so accepted for exchange; and

(iii) cause the Trustee promptly to authenticate and deliver to each Holder of Securities a principal amount of New Securities equal to the principal amount of the Securities of such Holder so accepted for exchange.

(e) Each Holder hereby acknowledges and agrees that any Broker-Dealer and any such Holder using the Registered Exchange Offer to participate in a distribution of the New Securities (x) could not under Commission policy as in effect on the date of this Agreement rely on the position of the Commission in MORGAN STANLEY AND CO., INC. (pub. avail. June 5, 1991) and EXXON CAPITAL HOLDINGS CORPORATION (pub. avail. May 13, 1988), as interpreted in the Commission's letter to SHEARMAN & STERLING dated July 2, 1993 and similar no-action letters; (y) must comply with the registration and prospectus delivery requirements of the Act in connection with any secondary resale transaction; and
(z) must be covered by an effective registration statement containing the selling security holder information required by Item 507 or 508, as applicable, of Regulation S-K under the Act if the resales are of New Securities obtained by such Holder in exchange for Securities acquired by such Holder directly from the Company or one of its Affiliates. Accordingly, each Holder participating in the Registered Exchange Offer shall be required to represent to the Company that, at the time of the consummation of the Registered Exchange Offer:

(i) any New Securities received by such Holder will be acquired in the ordinary course of business;

(ii) such Holder will have no arrangement or understanding with any Person to participate in the distribution of the Securities or the New Securities within the meaning of the Act; and

(iii) such Holder is not an Affiliate of the Company.

(f) If any Initial Purchaser determines that it is not eligible to participate in the Registered Exchange Offer with respect to the exchange of Securities constituting any portion of an unsold allotment, at the request of such Initial Purchaser, the Company shall issue

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and deliver to such Initial Purchaser or the Person purchasing New Securities registered under a Shelf Registration Statement as contemplated by Section 3 hereof from such Initial Purchaser, in exchange for such Securities, a like principal amount of New Securities. The Company shall use its best efforts to cause the CUSIP Service Bureau to issue the same CUSIP number for such New Securities as for New Securities issued pursuant to the Registered Exchange Offer.

3. SHELF REGISTRATION.

(a) If (i) due to any change in law or applicable interpretations thereof by the Commission's staff, the Company determines upon advice of its outside counsel that it is not permitted to effect the Registered Exchange Offer as contemplated by Section 2 hereof;

(ii) for any other reason the Registered Exchange Offer is not consummated within 270 days of the date hereof;

(iii) any Initial Purchaser so requests with respect to Securities that are not eligible to be exchanged for New Securities in the Registered Exchange Offer and that are held by it following consummation of the Registered Exchange Offer;

(iv) any Holder (other than an Initial Purchaser) is not eligible to participate in the Registered Exchange Offer; or

(v) in the case of any Initial Purchaser that participates in the Registered Exchange Offer or acquires New Securities pursuant to
Section 2(f) hereof, such Initial Purchaser does not receive freely tradeable New Securities in exchange for Securities constituting any portion of an unsold allotment (it being understood that (x) the requirement that an Initial Purchaser deliver a Prospectus containing the information required by Item 507 or 508 of Regulation S-K under the Act in connection with sales of New Securities acquired in exchange for such Securities shall result in such New Securities being not "freely tradeable"; and (y) the requirement that an Exchanging Dealer deliver a Prospectus in connection with sales of New Securities acquired in the Registered Exchange Offer in exchange for Securities acquired as a result of market-making activities or other trading activities shall not result in such New Securities being not "freely tradeable"), the Company shall effect a Shelf Registration Statement in accordance with subsection (b) below.

(b) (i) To the extent not prohibited by any applicable law or applicable interpretation of the Staff of the Commission, the Company shall as promptly as practicable (but in no event more than 60 days after so required or requested pursuant to this Section 3), file with the Commission and thereafter shall use its best efforts to cause to be declared effective under the Act a Shelf Registration Statement relating to the offer and sale of the Securities or the New Securities, as applicable, by the Holders thereof from time to time in accordance with the methods of distribution elected by such Holders and set forth in such Shelf Registration Statement; PROVIDED, HOWEVER, that no Holder (other than an Initial Purchaser) shall be entitled to have the Securities held by it covered by such Shelf Registration Statement unless such Holder agrees in writing to be bound by all of the provisions of this Agreement applicable to such

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Holder; and provided further, that with respect to New Securities received by an Initial Purchaser in exchange for Securities constituting any portion of an unsold allotment, the Company may, if permitted by current interpretations by the Commission's staff, file a post-effective amendment to the Exchange Offer Registration Statement containing the information required by Item 507 or 508 of Regulation S-K, as applicable, in satisfaction of its obligations under this subsection with respect thereto, and any such Exchange Offer Registration Statement, as so amended, shall be referred to herein as, and governed by the provisions herein applicable to, a Shelf Registration Statement.

(ii) The Company shall use its best efforts to keep the Shelf Registration Statement continuously effective, supplemented and amended as required by the Act, in order to permit the Prospectus forming part thereof to be usable by Holders for a period of two years from the date the Shelf Registration Statement is declared effective by the Commission or such shorter period that will terminate when all the Securities or New Securities, as applicable, covered by the Shelf Registration Statement have been sold pursuant to the Shelf Registration Statement (in any such case, such period being called the "Shelf Registration Period"). The Company shall be deemed not to have used its best efforts to keep the Shelf Registration Statement effective during the requisite period if it voluntarily takes any action that would result in Holders of Securities covered thereby not being able to offer and sell such Securities during that period, unless (A) such action is required by applicable law; or (B) such action is taken by the Company in good faith and for valid business reasons (not including avoidance of the Company's obligations hereunder), including the acquisition or divestiture of assets, business combinations or similar significant corporate transactions involving the Company or Exelon Corporation so long as the Company promptly thereafter complies with the requirements of Section 4(j) hereof, if applicable.

4. ADDITIONAL REGISTRATION PROCEDURES. In connection with any Shelf Registration Statement and, to the extent applicable, any Exchange Offer Registration Statement, the following provisions shall apply.

(a) The Company shall:

(i) furnish to you, not less than five Business Days prior to the filing thereof with the Commission, a copy of any Exchange Offer Registration Statement and any Shelf Registration Statement, and each amendment thereof and each amendment or supplement, if any, to the Prospectus included therein (including all documents incorporated by reference therein after the initial filing) and shall use its best efforts to reflect in each such document, when so filed with the Commission, such comments as you reasonably propose;

(ii) include the information set forth in Annex A hereto on the facing page of the Exchange Offer Registration Statement, in Annex B hereto in the forepart of the Exchange Offer Registration Statement in a section setting forth details of the Exchange Offer, in Annex C hereto in the underwriting or plan of distribution section of the Prospectus contained in the Exchange Offer

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Registration Statement, and in Annex D hereto in the letter of transmittal delivered pursuant to the Registered Exchange Offer;

(iii) if requested by an Initial Purchaser, include the information required by Item 507 or 508 of Regulation S-K, as applicable, in the Prospectus contained in the Exchange Offer Registration Statement or Shelf Registration Statement; and

(iv) in the case of a Shelf Registration Statement, include the names of the Holders that propose to sell Securities pursuant to the Shelf Registration Statement as selling security holders.

(b) The Company shall advise you, the Holders of Securities covered by any Shelf Registration Statement and any Exchanging Dealer under any Exchange Offer Registration Statement that has provided in writing to the Company a telephone or facsimile number and address for notices, and, if requested by you or any such Holder or Exchanging Dealer, shall confirm such advice in writing (which notice pursuant to clauses (ii)-(v) hereof shall be accompanied by an instruction to suspend the use of the Prospectus until the Company shall have remedied the basis for such suspension):

(i) when a Registration Statement and any amendment thereto has been filed with the Commission and when the Registration Statement or any post-effective amendment thereto has become effective;

(ii) of any request by the Commission for any amendment or supplement to the Registration Statement or the Prospectus or for additional information;

(iii) of the issuance by the Commission of any stop order suspending the effectiveness of the Registration Statement or the initiation of any proceedings for that purpose;

(iv) of the receipt by the Company of any notification with respect to the suspension of the qualification of the securities included therein for sale in any jurisdiction or the initiation of any proceeding for such purpose; and

(v) of the happening of any event that requires any change in the Registration Statement or the Prospectus so that, as of such date, the statements therein are not misleading and do not omit to state a material fact required to be stated therein or necessary to make the statements therein (in the case of the Prospectus, in the light of the circumstances under which they were made) not misleading.

(c) The Company shall use its best efforts to obtain the withdrawal of any order suspending the effectiveness of any Registration Statement or the qualification of the securities therein for sale in any jurisdiction at the earliest possible time.

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(d) The Company shall furnish to each Holder of Securities covered by any Shelf Registration Statement, without charge, at least one copy of such Shelf Registration Statement and any post-effective amendment thereto, including all material incorporated therein by reference, and, if the Holder so requests in writing, all exhibits thereto (including exhibits incorporated by reference therein).

(e) The Company shall, during the Shelf Registration Period, deliver to each Holder of Securities covered by any Shelf Registration Statement, without charge, as many copies of the Prospectus (including each preliminary Prospectus) included in such Shelf Registration Statement and any amendment or supplement thereto as such Holder may reasonably request. The Company consents to the use of the Prospectus or any amendment or supplement thereto by each of the selling Holders of Securities in connection with the offering and sale of the Securities covered by the Prospectus, or any amendment or supplement thereto, included in the Shelf Registration Statement.

(f) The Company shall furnish to each Exchanging Dealer which so requests, without charge, at least one copy of the Exchange Offer Registration Statement and any post-effective amendment thereto, including all material incorporated by reference therein, and, if the Exchanging Dealer so requests in writing, all exhibits thereto (including exhibits incorporated by reference therein).

(g) The Company shall promptly deliver to each Initial Purchaser, each Exchanging Dealer and each other Person required to deliver a Prospectus during the Exchange Offer Registration Period, without charge, as many copies of the Prospectus included in such Exchange Offer Registration Statement and any amendment or supplement thereto as any such Person may reasonably request. The Company consents to the use of the Prospectus or any amendment or supplement thereto by any Initial Purchaser, any Exchanging Dealer and any such other Person that may be required to deliver a Prospectus following the Registered Exchange Offer in connection with the offering and sale of the New Securities covered by the Prospectus, or any amendment or supplement thereto, included in the Exchange Offer Registration Statement.

(h) Prior to the Registered Exchange Offer or any other offering of Securities pursuant to any Registration Statement, the Company shall arrange, if necessary, for the qualification of the Securities or the New Securities for sale under the laws of such jurisdictions as any Holder shall reasonably request and will maintain such qualification in effect so long as required; provided that in no event shall the Company be obligated to qualify to do business in any jurisdiction where it is not then so qualified or to take any action that would subject it to service of process in suits, other than those arising out of the Initial Placement, the Registered Exchange Offer or any offering pursuant to a Shelf Registration Statement, in any such jurisdiction where it is not then so subject.

(i) The Company shall cooperate with the Holders of Securities to facilitate the timely preparation and delivery of certificates representing New Securities or Securities to be issued or sold pursuant to any Registration Statement free of any restrictive legends and in such denominations and registered in such names as Holders may request.

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(j) Upon the occurrence of any event contemplated by subsections
(b)(ii) through (v) above, the Company shall promptly prepare a post-effective amendment to the applicable Registration Statement or an amendment or supplement to the related Prospectus or file any other required document so that, as thereafter delivered to Initial Purchasers of the Securities included therein, the Prospectus will not include an untrue statement of a material fact or omit to state any material fact necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading. In such circumstances, the period of effectiveness of the Exchange Offer Registration Statement provided for in Section 2 and the Shelf Registration Statement provided for in Section 3(b) shall each be extended by the number of days from and including the date of the giving of a notice of suspension pursuant to
Section 4(b) to and including the date when the Initial Purchasers, the Holders of the Securities and any known Exchanging Dealer shall have received such amended or supplemented Prospectus pursuant to this Section.

(k) Not later than the effective date of any Registration Statement, the Company shall obtain the CUSIP number assigned to the Outstanding Securities for the Securities or the New Securities, as the case may be, registered under such Registration Statement and provide the Trustee with certificates for such Securities or New Securities, in a form eligible for deposit with The Depository Trust Company.

(l) The Company shall make generally available to its security holders as soon as practicable after the effective date of the applicable Registration Statement an earnings statement satisfying the provisions of
Section 11(a) of the Act.

(m) The Company shall cause the Mortgage to be qualified under the Trust Indenture Act in a timely manner.

(n) The Company may require each Holder of Securities to be sold pursuant to any Shelf Registration Statement to furnish to the Company such information regarding the Holder and the distribution of such Securities as the Company may from time to time reasonably require for inclusion in such Registration Statement. The Company may exclude from such Shelf Registration Statement the Securities of any Holder that unreasonably fails to furnish such information within a reasonable time after receiving such request and the Company shall be under no further obligations to such Holder to include such Holder in a Shelf Registration Statement.

(o) In the case of any Shelf Registration Statement, the Company shall enter into such and take all other appropriate actions (including if requested an underwriting agreement in customary form) in order to expedite or facilitate the registration or the disposition of the Securities, and in connection therewith, if an underwriting agreement is entered into, cause the same to contain indemnification provisions and procedures no less favorable than those set forth in Section 6 (or such other provisions and procedures acceptable to the Majority Holders and the Managing Underwriters, if any, with respect to all parties to be indemnified pursuant to Section 6.

(p) In the case of any Shelf Registration Statement, the Company shall:

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(i) subject to execution of a confidentiality agreement in form and substance reasonably acceptable to the Company and the Holders, make reasonably available for inspection by the Holders of Securities to be registered thereunder, any underwriter participating in any disposition pursuant to such Registration Statement, and any attorney, accountant or other agent retained by the Holders or any such underwriter all relevant financial and other records, pertinent corporate documents and properties of the Company and its subsidiaries;

(ii) cause the Company's officers, directors and employees to supply all relevant information reasonably requested by the Holders or any such underwriter, attorney, accountant or agent in connection with any such Registration Statement as is customary for similar due diligence examinations; provided, however, that any information that is designated in writing by the Company, in good faith, as confidential at the time of delivery of such information shall be kept confidential by the Holders or any such underwriter, attorney, accountant or agent, unless such disclosure is made in connection with a court proceeding or required by law, or such information becomes available to the public generally or through a third party without an accompanying obligation of confidentiality;

(iii) make such representations and warranties to the Holders of Securities registered thereunder and the underwriters, if any, in form, substance and scope as are customarily made by issuers to underwriters in underwritten offerings and covering those matters set forth in the Purchase Agreement;

(iv) obtain opinions of counsel to the Company and updates thereof (which counsel and opinions (in form, scope and substance) shall be reasonably satisfactory to the Managing Underwriters, if any) addressed to each selling Holder and the underwriters, if any, covering the matters covered in the opinion delivered under the Purchase Agreement and matters related to registration of the Securities under the Act and the qualification of the Mortgage under the Trust Indenture Act of 1940, as amended;

(v) obtain "cold comfort" letters and updates thereof from the independent certified public accountants of the Company (and, if necessary, any other independent certified public accountants of any subsidiary of the Company or of any business acquired by the Company for which financial statements and financial data are, or are required to be, included in the Registration Statement), addressed to each selling Holder of Securities registered thereunder and the underwriters, if any, in customary form and covering matters of the type customarily covered in "cold comfort" letters in connection with primary underwritten offerings; and

(vi) deliver such documents and certificates as may be reasonably requested by the Majority Holders and the Managing Underwriters, if any, including those to evidence compliance with
Section 4(k) and with any customary

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conditions contained in the underwriting agreement or other agreement entered into by the Company.

The actions set forth in clauses (iii), (iv), (v) and (vi) of this Section shall be performed at each closing under any underwriting or similar agreement as and to the extent required thereunder.

(q) If a Registered Exchange Offer is to be consummated, upon delivery of the Securities by Holders to the Company (or to such other Person as directed by the Company) in exchange for the New Securities, the Company shall mark, or caused to be marked, on the Securities so exchanged that such Securities are being canceled in exchange for the New Securities. In no event shall the Securities be marked as paid or otherwise satisfied.

(r) The Company will use its best efforts (i) if the Securities have been rated prior to the initial sale of such Securities pursuant to the Purchase Agreement, to confirm such ratings will apply to the Securities or the New Securities, as the case may be, covered by a Registration Statement; or (ii) if the Securities were not previously rated, to cause the Securities covered by a Registration Statement to be rated with at least one nationally recognized statistical rating agency, if so requested by Majority Holders with respect to the related Registration Statement or by any Managing Underwriters.

(s) In the event that any Broker-Dealer shall underwrite any Securities or participate as a member of an underwriting syndicate or selling group or "assist in the distribution" (within the meaning of the Rules of Fair Practice and the By-Laws of the National Association of Securities Dealers, Inc.) thereof, whether as a Holder of such Securities or as an underwriter, a placement or sales agent or a broker or dealer in respect thereof, or otherwise, assist such Broker-Dealer in complying with the requirements of such Rules and By-Laws, including, without limitation, by:

(i) if such Rules or By-Laws shall so require, engaging a "qualified independent underwriter" (as defined in such Rules) to participate in the preparation of the Registration Statement, to exercise usual standards of due diligence with respect thereto and, if any portion of the offering contemplated by such Registration Statement is an underwritten offering or is made through a placement or sales agent, to recommend the yield of such Securities;

(ii) indemnifying any such qualified independent underwriter to the extent of the indemnification of underwriters provided in Section 6 hereof; and

(iii) providing such information to such Broker-Dealer as may be required in order for such Broker-Dealer to comply with the requirements of such Rules.

(t) The Company shall use its best efforts to take all other steps necessary to effect the registration of the Securities or the New Securities, as the case may be, covered by a Registration Statement.

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5. REGISTRATION EXPENSES. The Company shall bear all expenses incurred in connection with the performance of its obligations under Sections 2, 3 and 4 hereof and, in the event of any Shelf Registration Statement, will reimburse the Holders for the reasonable fees and disbursements of one firm or counsel designated by the Majority Holders to act as counsel for the Holders in connection therewith, and, in the case of any Exchange Offer Registration Statement, will reimburse the Initial Purchasers for the reasonable fees and disbursements of their counsel incurred in connection with their review of the Exchange Offer Registration Statement.

6. INDEMNIFICATION AND CONTRIBUTION.

(a) The Company agrees to indemnify and hold harmless each Holder of Securities or New Securities, as the case may be, covered by any Registration Statement (including each Initial Purchaser and, with respect to any Prospectus delivery as contemplated in Section 4(h) hereof, each Exchanging Dealer), the directors, officers, employees and agents of each such Holder and each Person who controls any such Holder within the meaning of either the Act or the Exchange Act against any and all losses, claims, damages or liabilities, joint or several, to which they or any of them may become subject under the Act, the Exchange Act or other Federal or state statutory law or regulation, at common law or otherwise, insofar as such losses, claims, damages or liabilities (or actions in respect thereof) arise out of or are based upon any untrue statement or alleged untrue statement of a material fact contained in the Registration Statement as originally filed or in any amendment thereof, or in any preliminary Prospectus or the Prospectus, or in any amendment thereof or supplement thereto, or arise out of or are based upon the omission or alleged omission to state therein a material fact required to be stated therein or necessary to make the statements therein not misleading, and agrees to reimburse each such indemnified party, as incurred, for any legal or other expenses reasonably incurred by them in connection with investigating or defending any such loss, claim, damage, liability or action; provided, however, that the Company will not be liable in any case to the extent that any such loss, claim, damage or liability arises out of or is based upon any such untrue statement or alleged untrue statement or omission or alleged omission made therein in reliance upon and in conformity with written information furnished to the Company by or on behalf of any such Holder specifically for inclusion therein; provided, further, that such indemnity with respect to any untrue statement contained in or omission from the preliminary Prospectus shall not inure to the benefit of any Holder (or any person controlling such holder) from whom the person asserting such loss, claim, damage or liability purchased any of the Securities or New Securities which are the subject thereof if such person did not receive a copy of the Prospectus (or, if the Prospectus shall have been amended or supplemented, the Prospectus as then amended or supplemented), excluding incorporated documents, at or prior to the confirmation of sale of such securities or New Securities to such person in any case where such delivery is required by the Act and the untrue statement or omission of a material fact contained in such preliminary Prospectus was corrected in the Prospectus as then amended or supplemented), and it is finally judicially determined that such delivery was required to be made under the Act and was no so made. This indemnity agreement will be in addition to any liability which the Company may otherwise have.

The Company also agrees to indemnify or contribute as provided in Section 6(d) to Losses of each and any person deemed an "underwriter", under the Act or the rules and regulations thereunder, of Securities or New Securities, as the case may be, registered under a

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Shelf Registration Statement, their directors, officers, employees or agents and each Person who controls such underwriter on substantially the same basis as that of the indemnification of the Initial Purchasers and the selling Holders provided in this Section 6(a) and shall, if requested by any Holder, enter into an underwriting agreement reflecting such agreement, as provided in Section 4(p) hereof.

(b) Each Holder of securities covered by a Registration Statement (including each Initial Purchaser and, with respect to any Prospectus delivery as contemplated in Section 4(h) hereof, each Exchanging Dealer) severally agrees to indemnify and hold harmless the Company each of its directors each of its officers who signs such Registration Statement and each Person who controls the Company within the meaning of either the Act or the Exchange Act, to the same extent as the foregoing indemnity from the Company to each such Holder, but only with reference to written information relating to such Holder furnished to the Company by or on behalf of such Holder specifically for inclusion in the documents referred to in the foregoing indemnity. This indemnity agreement will be in addition to any liability which any such Holder may otherwise have.

(c) Promptly after receipt by an indemnified party under this Section 6 of notice of the commencement of any action, such indemnified party will, if a claim in respect thereof is to be made against the indemnifying party under this Section, notify the indemnifying party in writing of the commencement thereof; but the failure so to notify the indemnifying party (i) will not relieve it from liability under paragraph (a) or (b) above unless and to the extent it did not otherwise learn of such action and such failure results in the forfeiture by the indemnifying party of substantial rights and defenses; and (ii) will not, in any event, relieve the indemnifying party from any obligations to any indemnified party other than the indemnification obligation provided in paragraph (a) or (b) above. The indemnifying party shall be entitled to appoint counsel of the indemnifying party's choice at the indemnifying party's expense to represent the indemnified party in any action for which indemnification is sought (in which case the indemnifying party shall not thereafter be responsible for the fees and expenses of any separate counsel retained by the indemnified party or parties except as set forth below); provided, however, that such counsel shall be satisfactory to the indemnified party. Notwithstanding the indemnifying party's election to appoint counsel to represent the indemnified party in an action, the indemnified party shall have the right to employ separate counsel, and the indemnifying party shall bear the reasonable fees, costs and expenses of such separate counsel if (i) the use of counsel chosen by the indemnifying party to represent the indemnified party would present such counsel with a conflict of interest; (ii) the actual or potential defendants in, or targets of, any such action include both the indemnified party and the indemnifying party and the indemnified party shall have reasonably concluded that there may be legal defenses available to it and/or other indemnified parties which are different from or additional to those available to the indemnifying party; (iii) the indemnifying party shall not have employed counsel satisfactory to the indemnified party to represent the indemnified party within a reasonable time after notice of the institution of such action; or (iv) the indemnifying party shall authorize the indemnified party to employ separate counsel at the expense of the indemnifying party; provided, however, that the indemnifying party shall not be responsible for the fees and expenses of more than one separate firm representing indemnified parties described in clauses (i) or (ii) of this sentence. An indemnifying party will not, without the prior written consent of the indemnified parties, settle or compromise or consent to the entry of any judgment with respect to any pending or threatened

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claim, action, suit or proceeding in respect of which indemnification or contribution may be sought hereunder (whether or not the indemnified parties are actual or potential parties to such claim or action) unless such settlement, compromise or consent includes an unconditional release of each indemnified party from all liability arising out of such claim, action, suit or proceeding.

(d) In the event that the indemnity provided in paragraph (a) or (b) of this Section is for any reason held to be unenforceable by an indemnified party although applicable in accordance with its terms, then each applicable indemnifying party shall have a several and not joint obligation to contribute to the aggregate losses, claims, damages and liabilities (including legal or other expenses reasonably incurred in connection with investigating or defending same) (collectively "Losses") to which such indemnified party may be subject in such proportion as is appropriate to reflect the relative benefits received by such indemnifying party, on the one hand, and such indemnified party, on the other hand, from the Initial Placement and the Registration Statement which resulted in such Losses; provided, however, that in no case shall any Initial Purchaser or any subsequent Holder of any Security or New Security be responsible, in the aggregate, for any amount in excess of the purchase discount or commission applicable to such Security, or in the case of a New Security, applicable to the Security that was exchangeable into such New Security, as set forth on the cover page of the Final Memorandum, nor shall any underwriter be responsible for any amount in excess of the underwriting discount or commission applicable to the securities purchased by such underwriter under the Registration Statement which resulted in such Losses. If the allocation provided by the immediately preceding sentence is unavailable for any reason, the indemnifying party and the indemnified party shall contribute in such proportion as is appropriate to reflect not only such relative benefits but also the relative fault of such indemnifying party, on the one hand, and such indemnified party, on the other hand, in connection with the statements or omissions which resulted in such Losses as well as any other relevant equitable considerations. Benefits received by the Company shall be deemed to be equal to the sum of (x) the total net proceeds from the Initial Placement (before deducting expenses) as set forth on the cover page of the Final Memorandum and (y) the total amount of additional interest which the Company was not required to pay as a result of registering the securities covered by the Registration Statement which resulted in such Losses. Benefits received by the Initial Purchasers shall be deemed to be equal to the total purchase discounts and commissions as set forth on the cover page of the Final Memorandum, and benefits received by any other Holders shall be deemed to be equal to the value of receiving Securities or New Securities, as applicable, registered under the Act. Benefits received by any underwriter shall be deemed to be equal to the total underwriting discounts and commissions, as set forth on the cover page of the Prospectus forming a part of the Registration Statement which resulted in such Losses. Relative fault shall be determined by reference to, among other things, whether any alleged untrue statement or omission relates to information provided by the indemnifying party, on the one hand, or by the indemnified party, on the other hand, the intent of the parties and their relative knowledge, access to information and opportunity to correct or prevent such untrue statement or omission. The parties agree that it would not be just and equitable if contribution were determined by pro rata allocation (even if the Holders were treated as one entity for such purpose) or any other method of allocation which does not take account of the equitable considerations referred to above. Notwithstanding the provisions of this paragraph (d), no Person guilty of fraudulent misrepresentation (within the meaning of Section 11(f) of the Act) shall be entitled to contribution from any Person who was not guilty of such fraudulent misrepresentation. For purposes of this Section, each Person who controls a Holder within the

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meaning of either the Act or the Exchange Act and each director, officer, employee and agent of such Holder shall have the same rights to contribution as such Holder, and each Person who controls the Company within the meaning of either the Act or the Exchange Act, each officer of the Company who shall have signed the Registration Statement and each director of the Company shall have the same rights to contribution as the Company, subject in each case to the applicable terms and conditions of this paragraph (d).

(e) The provisions of this Section will remain in full force and effect, regardless of any investigation made by or on behalf of any Holder or the Company or any of the officers, directors or controlling Persons referred to in this Section hereof, and will survive the sale by a Holder of securities covered by a Registration Statement.

7. UNDERWRITTEN REGISTRATIONS.

(a) If any of the Securities or New Securities, as the case may be, covered by any Shelf Registration Statement are to be sold in an underwritten offering, the Managing Underwriters shall be selected by the Majority Holders.

(b) No Person may participate in any underwritten offering pursuant to any Shelf Registration Statement, unless such Person (i) agrees to sell such Person's Securities or New Securities, as the case may be, on the basis reasonably provided in any underwriting arrangements approved by the Persons entitled hereunder to approve such arrangements; and (ii) completes and executes all questionnaires, powers of attorney, indemnities, underwriting agreements and other documents reasonably required under the terms of such underwriting arrangements.

8. NO INCONSISTENT AGREEMENTS. The Company has not, as of the date hereof, entered into, nor shall it, on or after the date hereof, enter into, any agreement with respect to its securities that is inconsistent with the rights granted to the Holders herein or otherwise conflicts with the provisions hereof.

9. AMENDMENTS AND WAIVERS. The provisions of this Agreement, including the provisions of this sentence, may not be amended, qualified, modified or supplemented, and waivers or consents to departures from the provisions hereof may not be given, unless the Company has obtained the written consent of the Majority Holders (or, after the consummation of any Registered Exchange Offer in accordance with Section 2 hereof, of New Securities); provided that, with respect to any matter that directly or indirectly affects the rights of any Initial Purchaser hereunder, the Company shall obtain the written consent of each such Initial Purchaser against which such amendment, qualification, supplement, waiver or consent is to be effective. Notwithstanding the foregoing (except the foregoing proviso), a waiver or consent to departure from the provisions hereof with respect to a matter that relates exclusively to the rights of Holders whose Securities or New Securities, as the case may be, are being sold pursuant to a Registration Statement and that does not directly or indirectly affect the rights of other Holders may be given by the Majority Holders, determined on the basis of Securities or New Securities, as the case may be, being sold rather than registered under such Registration Statement.

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10. NOTICES. All notices and other communications provided for or permitted hereunder shall be made in writing by hand-delivery, first-class mail, telex, telecopier or air courier guaranteeing overnight delivery:

(a) if to a Holder, at the most current address given by such holder to the Company in accordance with the provisions of this Section, which address initially is, with respect to each Holder, the address of such Holder maintained by the Registrar under the Mortgage, with a copy in like manner to Barclays Capital Inc. at its address set forth in the Purchase Agreement;

(b) if to you, initially at the respective addresses set forth in the Purchase Agreement; and

(c) if to the Company, initially at its address set forth in the Purchase Agreement.

All such notices and communications shall be deemed to have been duly given when received.

The Initial Purchasers or the Company by notice to the other parties may designate additional or different addresses for subsequent notices or communications.

11. SUCCESSORS. This Agreement shall inure to the benefit of and be binding upon the successors and assigns of each of the parties, including, without the need for an express assignment or any consent by the Company thereto, subsequent Holders of Securities and the New Securities. The Company hereby agrees to extend the benefits of this Agreement to any Holder of Securities and the New Securities, and any such Holder may specifically enforce the provisions of this Agreement as if an original party hereto.

12. COUNTERPARTS. This agreement may be in signed counterparts, each of which shall an original and all of which together shall constitute one and the same agreement.

13. HEADINGS. The headings used herein are for convenience only and shall not affect the construction hereof.

14. APPLICABLE LAW. This Agreement shall be governed by and construed in accordance with the laws of the State of New York applicable to contracts made and to be performed in the State of New York.

15. SEVERABILITY. In the event that any one of more of the provisions contained herein, or the application thereof in any circumstances, is held invalid, illegal or unenforceable in any respect for any reason, the validity, legality and enforceability of any such provision in every other respect and of the remaining provisions hereof shall not be in any way impaired or affected thereby, it being intended that all of the rights and privileges of the parties shall be enforceable to the fullest extent permitted by law.

16. SECURITIES HELD BY THE COMPANY, ETC. Whenever the consent or approval of Holders of a specified percentage of principal amount of Securities or New Securities is required

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hereunder, Securities or New Securities, as applicable, held by the Company or its Affiliates (other than subsequent Holders of Securities or New Securities if such subsequent Holders are deemed to be Affiliates solely by reason of their holdings of such Securities or New Securities) shall not be counted in determining whether such consent or approval was given by the Holders of such required percentage.

[signature page follows]

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If the foregoing is in accordance with your understanding of our agreement, please sign and return to us the enclosed duplicate hereof, whereupon this letter and your acceptance shall represent a binding agreement among the Company and the several Initial Purchasers.

Very truly yours,

COMMONWEALTH EDISON COMPANY

By:

Name:
Title:

The foregoing Agreement is hereby confirmed and accepted as of the date first above written.

BARCLAYS CAPITAL INC.
FIRST UNION SECURITIES, INC.

By: Barclays Capital Inc.

By:
Name:
Title:

For themselves and the other
several Initial Purchasers
named in Schedule I to the
Purchase Agreement.

ANNEX A

Each Broker-Dealer that receives New Securities for its own account pursuant to the Exchange Offer must acknowledge that it will deliver a prospectus in connection with any resale of such New Securities. The Letter of Transmittal states that by so acknowledging and by delivering a prospectus, a Broker-Dealer will not be deemed to admit that it is an "underwriter" within the meaning of the Securities Act. This Prospectus, as it may be amended or supplemented from time to time, may be used by a Broker-Dealer in connection with resales of New Securities received in exchange for Securities where such Securities were acquired by such Broker-Dealer as a result of market-making activities or other trading activities. The Company has agreed that, starting on the Expiration Date (as defined herein) and ending on the close of business one year after the Expiration Date, it will make this Prospectus available to any Broker-Dealer for use in connection with any such resale. See "Plan of Distribution".

ANNEX B

Each Broker-Dealer that receives New Securities for its own account in exchange for Securities, where such Securities were acquired by such Broker-Dealer as a result of market-making activities or other trading activities, must acknowledge that it will deliver a prospectus in connection with any resale of such New Securities. See "Plan of Distribution".

ANNEX C

PLAN OF DISTRIBUTION

Each Broker-Dealer that receives New Securities for its own account pursuant to the Exchange Offer must acknowledge that it will deliver a prospectus in connection with any resale of such New Securities. This Prospectus, as it may be amended or supplemented from time to time, may be used by a Broker-Dealer in connection with resales of New Securities received in exchange for Securities where such Securities were acquired as a result of market-making activities or other trading activities. The Company has agreed that, starting on the Expiration Date and ending on the close of business one year after the Expiration Date, it will make this Prospectus, as amended or supplemented, available to any Broker-Dealer for use in connection with any such resale. In addition, until __________, 20___, all dealers effecting transactions in the New Securities may be required to deliver a prospectus.

The Company will not receive any proceeds from any sale of New Securities by brokers-dealers. New Securities received by Broker-Dealers for their own account pursuant to the Exchange Offer may be sold from time to time in one or more transactions in the over-the-counter market, in negotiated transactions, through the writing of options on the New Securities or a combination of such methods of resale, at market prices prevailing at the time of resale, at prices related to such prevailing market prices or negotiated prices. Any such resale may be made directly to purchasers or to or through brokers or dealers who may receive compensation in the form of commissions or concessions from any such Broker-Dealer and/or the purchasers of any such New Securities. Any Broker-Dealer that resells New Securities that were received by it for its own account pursuant to the Exchange Offer and any broker or dealer that participates in a distribution of such New Securities may be deemed to be an "underwriter" within the meaning of the Securities Act and any profit of any such resale of New Securities and any commissions or concessions received by any such Persons may be deemed to be underwriting compensation under the Securities Act. The Letter of Transmittal states that by acknowledging that it will deliver and by delivering a prospectus, a Broker-Dealer will not be deemed to admit that it is an "underwriter" within the meaning of the Securities Act.

For a period of one year after the Expiration Date, the Company will promptly send additional copies of this Prospectus and any amendment or supplement to this Prospectus to any Broker-Dealer that requests such documents in the Letter of Transmittal. The Company has agreed to pay all expenses incident to the Exchange Offer (including the expenses of one counsel for the holder of the Securities) other than commissions or concessions of any brokers or dealers and will indemnify the holders of the Securities (including any Broker-Dealers) against certain liabilities, including liabilities under the Securities Act.

ANNEX D

RIDER A

CHECK HERE IF YOU ARE A BROKER-DEALER AND WISH TO RECEIVE 10 ADDITIONAL COPIES OF THE PROSPECTUS AND 10 COPIES OF ANY AMENDMENTS OR SUPPLEMENTS THERETO.

Name:
Address:

RIDER B

If the undersigned is not a Broker-Dealer, the undersigned represents that it acquired the New Securities in the ordinary course of its business, it is not engaged in, and does not intend to engage in, a distribution of New Securities and it has not arrangements or understandings with any Person to participate in a distribution of the New Securities. If the undersigned is a Broker-Dealer that will receive New Securities for its own account in exchange for Securities, it represents that the Securities to be exchanged for New Securities were acquired by it as a result of market-making activities or other trading activities and acknowledges that it will deliver a prospectus in connection with any resale of such New Securities; however, by so acknowledging and by delivering a prospectus, the undersigned will not be deemed to admit that it is an "underwriter" within the meaning of the Securities Act.

EXHIBIT 4.6

FIRST MORTGAGE 6.15% BOND, FIRST MORTGAGE 6.15% BOND,
SERIES 98 DUE MARCH 15, 2012 SERIES 98 DUE MARCH 15, 2012

COMMONWEALTH EDISON COMPANY

Commonwealth Edison Company, an Illinois corporation (hereinafter called the "COMPANY"), for value received, hereby promises to pay to

CUSIP 202795 ____

SEE REVERSE FOR
CERTAIN DEFINITIONS

or registered assigns, the sum of DOLLARS

on the fifteenth day of March, 2012, and to pay interest on said sum from the date hereof until said sum shall be paid, at the rate of six and fifteen hundredths per centum (6.15%) per annum, payable semi-annually on the fifteenth day of March and the fifteenth day of September in each year. The interest so payable on any interest payment date will, subject to certain exceptions provided in the Mortgage hereinafter referred to, be paid to the person in whose name this bond is registered at the close of business on the March 1 or the September 1, as the case may be, next preceding such interest payment date. Both the principal of and the interest on this bond shall be payable at the office or agency of the Company in the City of Chicago, State of Illinois, or, at the option of the registered owner, at the office or agency of the Company in the Borough of Manhattan, The City of New York, State of New York, in any coin or currency of the United States of America which at the time of payment is legal tender for the payment of public and private debts.

(Additional provisions of this bond are set forth on the reverse hereof.)

This Bond shall not be entitled to any security or benefit under the Mortgage or be valid or become obligatory for any purpose unless and until it shall have been authenticated by the execution by the corporate Trustee, or its successor in trust under the Mortgage, of the certificate endorsed hereon.

Witness the due execution hereof by the Company under its corporate seal.

COMMONWEALTH EDISON COMPANY 

Dated

    TRUSTEE'S CERTIFICATE                    By:
This bond is one of the bonds of the
series designated therein, referred to
and described in the within mentioned
Supplemental Indenture dated as
of __________, 2002
                                                                   President

BNY MIDWEST TRUST COMPANY

By                                           Attest:
  ------------------------
    Authorized Signatory

                                                                   Secretary

ILLINOIS COMMERCE COMMISSION IDENTIFICATION NO. _______

COMMONWEALTH EDISON COMPANY

This bond is one of the bonds of the Company, issued and to be issued in series from time to time under and in accordance with and, irrespective of the time of issue, equally and ratably secured by the Mortgage of the Company dated July 1, 1923, and indentures supplemental thereto, under which BNY Midwest Trust Company and D. G. Donovan are now the Trustees, and is one of the First Mortgage 6.15% Bonds, Series 98, of the Company the issuance of which is provided for by a Supplemental Indenture dated as of ________, 2002 (the "SUPPLEMENTAL INDENTURE"), executed and delivered by the Company to such Trustees, to which Mortgage and all indentures supplemental thereto reference is hereby made for a description of the property mortgaged and pledged, the nature and extent of the security, the rights of the registered owners of said bonds, of the Company and of the Trustees in respect of the security, and the terms and conditions governing the issuance and security of said bonds. The term "Mortgage," as hereinafter used, shall mean said Mortgage dated July 1, 1923, and all indentures supplemental thereto.

With the consent of the Company and to the extent permitted by and as provided in the Mortgage, modifications or alterations of the Mortgage or of any indenture supplemental thereto and of the rights and obligations of the Company and of the holders and registered owners of the bonds may be made, and compliance with any provision of the Mortgage or any such supplemental indenture may be waived, by the affirmative vote of the holders and registered owners of not less than eighty per centum (80%) in principal amount of the bonds then outstanding under the Mortgage, and by the affirmative vote of the holders and registered owners of not less then eighty per centum (80%) in principal amount of the bonds of any series then outstanding under the Mortgage and affected by such modification or alteration, in case one or more but less than all of the series of bonds then outstanding under the Mortgage are so affected, but in any case excluding bonds, disqualified from voting by reason of the Company's interest therein as provided in the Mortgage; subject, however, to the condition, among other conditions stated in the Mortgage, that no such modification or alteration shall be made which will permit the extension of the time or times of payment of the principal of or the interest or the premium, if any, on this bond, or the reduction in the principal amount hereof or in the rate of interest or the amount of any premium hereon, or any other modification in the terms of payment of such principal, interest or premium, which terms of payment are unconditional, or otherwise than as permitted by the Mortgage, the creation of any lien ranking prior to or on a parity with the lien of the Mortgage with respect to any of the mortgaged property, all as more fully provided in the Mortgage.

The bonds of Series 98 shall be redeemable, at the option of the Company, as a whole or in part, at any time upon notice sent by the Company through the mail, postage prepaid, at least thirty (30) days and not more than forty-five
(45) days prior to the date fixed for redemption, to the registered holder of each bond to be redeemed in whole or in part, addressed to such holder at his address appearing upon the registration books, at the redemption price specified in Section 7 of the Supplemental Indenture. In case the Company shall desire to exercise such right to redeem and pay off all or any part of the bonds of Series 98, it shall comply with all the terms and provisions of Article V of the Mortgage applicable thereto, and such redemption shall be made under and subject to the terms and provisions of Article V and in the manner and with the effect therein provided, but at the time or times and upon mailing of notice, as set forth in Section 7 of the Supplemental Indenture. No publication of notice of any redemption of any bonds of Series 98 shall be required under Section 5.03(a) of the Mortgage.

No recourse shall be had for the payment of the principal of or the interest on this bond, or from any claim based hereon, or otherwise in respect hereof or of the Mortgage, to or against any incorporator, stockholder, officer or director, past, present or future, of the Company or of any successor corporation, either directly or through the Company or such successor corporation, under any constitution or statute or rule of law, or by the enforcement of any assessment or penalty, or otherwise, all such liability of incorporators, stockholders, directors and officers being waived and released by the registered owner hereof by the acceptance of this bond and being likewise waived and released by the terms of the Mortgage, all as more fully provided therein.

This bond is transferable by the registered owner hereof, in person or by duly authorized attorney, at the office or agency of the Company in the City of Chicago, State of Illinois, or, at the option of the registered owner, at the office or agency of the Company in the Borough of Manhattan, The City of New York, State of New York, upon surrender and cancellation of this bond; and thereupon a new registered bond or bonds without coupons of the same aggregate principal amount and series will be issued to the transferee in exchange hereof.

Bonds of this Series 98 are issuable only in registered form without coupons and in the denomination of $1,000 each and any authorized multiple thereof. As provided in the Mortgage, such bonds are exchangeable as between authorized denominations. Any such exchange may be made by the registered owner of any such bond or bonds upon presentation thereof for that purpose at the office or agency of the Company in the City of Chicago, State of Illinois, or, at the option of the registered owner, at the office or agency of the Company in the Borough of Manhattan, The City of New York, State of New York.

No charge will be made by the Company to the registered owner of this bond for the transfer hereof or for the exchange hereof for bonds of this Series 98 of other authorized denominations, except, in the case of transfer, a charge sufficient to reimburse the Company for any stamp or other tax or governmental charge required to be paid by the Company or the corporate Trustee.

ABBREVIATIONS

The following abbreviations, when used in the inscription on the face of this instrument, shall be construed as though they were written out in full according to applicable laws or regulations: 

TEN COM - as tenants in common                                UNIF GIFT MIN ACT - _____________ Custodian ____________
TEN ENT - as tenants by the entireties                                               (Cust)                  (Minor)
JT TEN - as joint tenants with rights of survivorship         under ___________________________Uniform Gifts to Minors Act
         survivorship and not as tenants in common                          (State)

Additional abbreviations may also be used though not in the above list.

FOR VALUE RECEIVED the undersigned hereby sell(s), assigns and transfer(s) unto

PLEASE INSERT SOCIAL SECURITY OR OTHER
IDENTIFYING NUMBER OF ASSIGNEE _______________________________

Please print or typewrite name and address including postal zip code of assignee

the within Bond and all rights thereunder, hereby irrevocably constituting and appointing

attorney to transfer said Bond on the books of the Company, with full power of substitution in the premises.

Dated:

UNLESS THIS BOND IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY, A NEW YORK CORPORATION ("DTC"), TO THE COMPANY OR ITS AGENT FOR REGISTRATION OF TRANSFER, EXCHANGE OR PAYMENT, AND ANY BOND ISSUED IS REGISTERED IN THE NAME OF CEDE & CO. OR IN SUCH OTHER NAME AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC (AND ANY PAYMENT IS MADE TO CEDE & CO. OR TO SUCH OTHER ENTITY AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY A PERSON IS WRONGFUL INASMUCH AS THE REGISTERED OWNER HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.

THIS BOND (OR ITS PREDECESSOR) WAS ORIGINALLY ISSUED IN A TRANSACTION EXEMPT FROM REGISTRATION UNDER THE UNITED STATES SECURITIES ACT OF 1933, AS AMENDED ("SECURITIES ACT"), AND MAY NOT BE OFFERED, SOLD, PLEDGED OR OTHERWISE TRANSFERRED IN THE ABSENCE OF SUCH REGISTRATION OR AN APPLICABLE EXEMPTION THEREFROM AND IN ANY EVENT MAY BE SOLD OR OTHERWISE TRANSFERRED ONLY IN ACCORDANCE WITH THE MORTGAGE, COPIES OF WHICH ARE AVAILABLE FOR INSPECTION AT THE OFFICE OF THE MORTGAGE TRUSTEE IN THE CITY OF CHICAGO, ILLINOIS.

EACH PURCHASER OF THIS BOND IS HEREBY NOTIFIED THAT THE SELLER MAY BE RELYING ON THE EXEMPTION FROM THE PROVISIONS OF SECTION 5 OF THE SECURITIES ACT PROVIDED BY RULE 144A THEREUNDER. EACH HOLDER OF THIS BOND REPRESENTS TO COMMONWEALTH EDISON COMPANY THAT (A) SUCH HOLDER WILL NOT SELL, PLEDGE OR OTHERWISE TRANSFER THIS BOND (WITHOUT THE CONSENT OF COMMONWEALTH EDISON COMPANY) OTHER THAN (1) TO A QUALIFIED INSTITUTIONAL BUYER IN A TRANSACTION COMPLYING WITH RULE 144A UNDER THE SECURITIES ACT, (2) IN ACCORDANCE WITH RULE 144 UNDER THE SECURITIES ACT,
(3) OUTSIDE THE UNITED STATES IN A TRANSACTION MEETING THE REQUIREMENTS OF REGULATION S UNDER THE SECURITIES ACT, (4) PURSUANT TO ANOTHER AVAILABLE EXEMPTION FROM REGISTRATION UNDER THE SECURITIES ACT, SUBJECT, IN THE CASE OF CLAUSES (2), (3) OR (4), TO THE RECEIPT BY COMMONWEALTH EDISON COMPANY OF AN OPINION OF COUNSEL OR SUCH OTHER EVIDENCE ACCEPTABLE TO COMMONWEALTH EDISON COMPANY THAT SUCH RESALE, PLEDGE OR TRANSFER IS EXEMPT FROM THE REGISTRATION REQUIREMENTS OF THE SECURITIES ACT OR (5) PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT AND THAT (B) THE HOLDER WILL, AND EACH SUBSEQUENT HOLDER IS REQUIRED TO, NOTIFY ANY PURCHASER OF THIS BOND OF THE RESALE RESTRICTIONS REFERRED TO HEREIN AND DELIVER TO THE TRANSFEREE (OTHER THAN A QUALIFIED INSTITUTIONAL BUYER) PRIOR TO THE SALE A COPY OF THE TRANSFER RESTRICTIONS APPLICABLE HERETO (COPIES OF WHICH MAY BE OBTAINED FROM THE MORTGAGE TRUSTEE).

Exhibit 5.1

Sidley Austin Brown & Wood
Bank One Plaza
10 South Dearborn Street
Chicago, Illinois 60603

September 18, 2002

Commonwealth Edison Company
37th Floor
10 South Dearborn Street
Chicago, Illinois 60680-5379

Re: $600,000,000 First Mortgage 6.15% Bonds, Series 98 Due March 15, 2012 of Commonwealth Edison Company

Ladies and Gentlemen:

We refer to the Registration Statement on Form S-4 (the "Registration Statement") being filed by Commonwealth Edison Company, an Illinois corporation
(the "Company"), with the Securities and Exchange Commission (the "Commission")
under the Securities Act of 1933, as amended (the "Securities Act"), relating to the registration of $600,000,000 principal amount of the Company's First Mortgage 6.15% Bonds, Series 98 Due March 15, 2012 (the "Exchange Bonds"), which are to be offered in exchange for an equivalent principal amount of currently outstanding First Mortgage 6.15% Bonds, Series 98 Due March 15, 2012 (the "Outstanding Bonds"), all as more fully described in the Registration Statement. The Exchange Bonds will be issued under the Company's Mortgage (the "Mortgage") dated July 1, 1923, as amended and supplemented, between the Company and Illinois Merchants Trust Company, as trustee (BNY Midwest Trust Company, as current successor trustee) and D.G. Donovan as Co-Trustee (collectively the "Bonds Trustees").

We are familiar with the proceedings to date with respect to the proposed issuance of the Exchange Bonds contemplated by the Registration Statement and have examined such records, documents and questions of law, and satisfied ourselves as to such matters of fact, as we have considered relevant and necessary as a basis for this opinion letter.

Based on the foregoing, we are of the opinion that:

1. The Company is a corporation duly organized and validly existing under the laws of the state of Illinois.

2. The Company has corporate power to execute and deliver indentures supplemental to the Mortgage and to authorize and issue the Exchange Bonds in exchange for the Outstanding Bonds.

Commonwealth Edison Company
September 18, 2002

Page 2

3. The Exchange Bonds will be legally issued and binding obligations of the Company (except to the extent enforceability may be limited by applicable bankruptcy, insolvency, reorganization, moratorium, fraudulent transfer or other similar laws affecting the enforcement of creditors' rights generally and by the effect of general principles of equity, regardless of whether considered in a proceeding in equity or at law) when: (i) the Registration Statement, as finally amended (including any necessary post-effective amendments), shall have become effective under the Securities Act; (ii) a supplemental indenture related to the Exchange Bonds meeting the requirements of the Mortgage has been duly executed and delivered by the Company and the Bonds Trustees; (iii) the Company's Board of Directors or a duly authorized committee thereof shall have duly adopted final resolutions authorizing the issuance and sale of the Exchange Bonds, as contemplated by the Registration Statement and the Mortgage; and (iv) the Exchange Bonds shall have been duly executed and authenticated as provided in the Mortgage and such resolutions and shall have been duly delivered to the purchasers thereof against surrender and cancellation of a like principal amount of Outstanding Bonds in the manner described in the Registration Statement.

The opinions expressed herein are limited to the laws of the State of Illinois and the federal laws of the United States of America.

We do not find it necessary for the purposes of this opinion letter to cover, and accordingly we express no opinion as to, the application of the securities or blue sky laws of the various states or the District of Columbia to the exchange of the Exchange Bonds.

We hereby consent to the filing of this opinion as an Exhibit to the Registration Statement and to all references to our firm included in or made a part of the Registration Statement.

Very truly yours,

Sidley Austin Brown & Wood

Exhibit 8.1

Sidley Austin Brown & Wood
Bank One Plaza
10 South Dearborn Street
Chicago, Illinois 60603

September 18, 2002

Commonwealth Edison Company
37th Floor
10 South Dearborn Street
Chicago, Illinois 60680-5379

Re: $600,000,000 First Mortgage 6.15% Bonds, Series 98 Due March 15, 2012 of Commonwealth Edison Company

Ladies and Gentlemen:

We have acted as United States tax counsel to Commonwealth Edison Company, an Illinois corporation (the "Company"), in connection with the Registration Statement on Form S-4 (the "Registration Statement") being filed by the Company with the Securities and Exchange Commission (the "Commission") under the Securities Act of 1933, as amended (the "Securities Act"), relating to the registration of $600,000,000 principal amount of the Company's First Mortgage 6.15% Bonds, Series 98 Due March 15, 2012 (the "Exchange Bonds"), which are to be offered in exchange for an equivalent principal amount of currently outstanding First Mortgage 6.15% Bonds, Series 98 Due March 15, 2012 (the "Outstanding Bonds"), all as more fully described in the Registration Statement.

We are familiar with the proceedings to date with respect to the proposed issuance of the Exchange Bonds contemplated by the Registration Statement and have examined such records, documents and questions of law, and satisfied ourselves as to such matters of fact, as we have considered relevant and necessary as a basis for this opinion. In addition, we have assumed that there will be no change in the laws currently applicable to the Company and that such laws will be the only laws applicable to the Company.

Based upon and subject to the foregoing, we are of the opinion that the statements set forth in the Registration Statement under the heading "Summary of United States Federal Income Tax Considerations" to the extent they constitute matters of federal income tax law or legal conclusions with respect thereto are correct in all material respects.

In giving the foregoing opinion, we express no opinion as to the laws of any jurisdiction other than the law of the United States of America.

Commonwealth Edison Company
September 18, 2002

Page 2

We are furnishing this opinion to the Company for its benefit in connection with the filing of the Registration Statement with the Commission, and this opinion is not to be used, circulated, quoted or otherwise referred to for any other purpose without our prior written permission.

This opinion letter is limited to the matters stated herein and no opinion is implied or may be inferred beyond the matters expressly stated herein. This opinion is rendered as of the date hereof based on the law and facts in existence on the date hereof, and we do not undertake, and hereby disclaim, any obligation to advise you of any changes in law or fact, whether or not material, which may be brought to our attention at a later date.

We consent to the filing of this opinion as Exhibit 8.1 to the Registration Statement. In giving this consent, we do not hereby admit that we are within the category of persons whose consent is required under Section 7 of the Securities Act of 1933, as amended, or the rules or regulations of the Commission promulgated thereunder.

Very truly yours,

Sidley Austin Brown & Wood

EXHIBIT 23.1

CONSENT OF INDEPENDENT ACCOUNTANTS

We hereby consent to the incorporation by reference in this Registration Statement on Form S-4 of Commonwealth Edison Company of our report dated January 29, 2002, except for Note 19 for which the date is March 21, 2002, relating to the financial statements and financial statement schedule, which appears in Commonwealth Edison Company's Annual Report on Form 10-K for the year ended December 31, 2001. We also consent to the references to us under the headings "Experts" and "Summary Financial Information" in such Registration Statement.

PricewaterhouseCoopers LLP

Chicago, Illinois
September 17, 2002

EXHIBIT 25.1

FORM T-1

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF ELIGIBILITY
UNDER THE TRUST INDENTURE ACT OF 1939 OF A
CORPORATION DESIGNATED TO ACT AS TRUSTEE

CHECK IF AN APPLICATION TO DETERMINE
ELIGIBILITY OF A TRUSTEE PURSUANT TO
SECTION 305(b)(2) / /

BNY MIDWEST TRUST COMPANY
(formerly known as CTC Illinois Trust Company)

(Exact name of trustee as specified in its charter) 

Illinois                                                     36-3800435
(State of incorporation                                      (I.R.S. employer
if not a U.S. national bank)                                 identification no.)

2 North LaSalle Street
Suite 1020
Chicago, Illinois                                            60602
(Address of principal executive offices)                     (Zip code)

                          ---------------------------

COMMONWEALTH EDISON COMPANY
(Exact name of obligor as specified in its charter) 

Illinois                                                     36-0938600
(State or other jurisdiction of                              (I.R.S. employer
incorporation or organization)                               identification no.)

37th Floor
10 South Dearborn Street
Post Office Box 805379
Chicago, Illinois                                            60680
(Address of principal executive offices)                     (Zip code)

                          ---------------------------

First Mortgage 6.15% Bonds, Series 98 due March 15, 2012
(Title of the indenture securities)

1. GENERAL INFORMATION. FURNISH THE FOLLOWING INFORMATION AS TO THE TRUSTEE:
(a) NAME AND ADDRESS OF EACH EXAMINING OR SUPERVISING AUTHORITY TO WHICH IT IS SUBJECT. 

--------------------------------------------------------------------------------
                    Name                                     Address
-------------------------------------------   ----------------------------------
     Office of Banks & Trust Companies of       500 E. Monroe Street
     the State of Illinois                      Springfield, Illinois 62701-1532

     Federal Reserve Bank of Chicago            230 S. LaSalle Street
                                                Chicago, Illinois 60603

(b) WHETHER IT IS AUTHORIZED TO EXERCISE CORPORATE TRUST POWERS.

Yes.

2. AFFILIATIONS WITH OBLIGOR.

IF THE OBLIGOR IS AN AFFILIATE OF THE TRUSTEE, DESCRIBE EACH SUCH
AFFILIATION.

None.

16. LIST OF EXHIBITS.

EXHIBITS IDENTIFIED IN PARENTHESES BELOW, ON FILE WITH THE COMMISSION, ARE INCORPORATED HEREIN BY REFERENCE AS AN EXHIBIT HERETO, PURSUANT TO RULE 7a-29 UNDER THE TRUST INDENTURE ACT OF 1939 (THE "ACT") AND 17 C.F.R. 229.10(d).

1. A copy of Articles of Incorporation of BNY Midwest Trust Company (formerly CTC Illinois Trust Company, formerly Continental Trust Company) as now in effect. (Exhibit 1 to Form T-1 filed with the Registration Statement No. 333-47688.)

2,3. A copy of the Certificate of Authority of the Trustee as now in effect, which contains the authority to commence business and a grant of powers to exercise corporate trust powers. (Exhibit 2 to Form T-1 filed with the Registration Statement No. 333-47688.)

4. A copy of the existing By-laws of the Trustee. (Exhibit 4 to Form T-1 filed with the Registration Statement No. 333-47688.)

6. The consent of the Trustee required by Section 321(b) of the Act.
(Exhibit 6 to Form T-1 filed with the Registration Statement No. 333-47688.)

-2-

7. A copy of the latest report of condition of the Trustee published pursuant to law or to the requirements of its supervising or examining authority.

-3-

SIGNATURE

Pursuant to the requirements of the Act, the Trustee, BNY Midwest Trust Company, a corporation organized and existing under the laws of the State of Illinois, has duly caused this statement of eligibility to be signed on its behalf by the undersigned, thereunto duly authorized, all in The City of Chicago, and State of Illinois, on the 22nd day of August, 2002.

BNY Midwest Trust Company 

By:   /s/ MARY CALLAHAN
  ---------------------------------------
   Name:  MARY CALLAHAN
   Title: ASSISTANT VICE PRESIDENT

-4-

OFFICE OF BANKS AND REAL ESTATE
BUREAU OF BANKS AND TRUST COMPANIES

CONSOLIDATED REPORT OF CONDITION
OF

BNY MIDWEST TRUST COMPANY
209 WEST JACKSON BOULEVARD
SUITE 700
CHICAGO, ILLINOIS 60606

Including the institution's domestic and foreign subsidiaries completed as of the close of business on December 31, 2001, submitted in response to the call of the Office of Banks and Real Estate of the State of Illinois. 

                                 ASSETS                                  THOUSANDS OF DOLLARS
                                 ------                                  --------------------
1.  Cash and Due from Depository Institutions...................               11,694

2.  U.S. Treasury Securities....................................                - 0 -

3.  Obligations of States and Political Subdivisions............                - 0 -

4.  Other Bonds, Notes and Debentures...........................                - 0 -

5.  Corporate Stock.............................................                - 0 -

6.  Trust Company  Premises,  Furniture,  Fixtures and Other
    Assets Representing Trust Company Premises..................                 363

7.  Leases and Lease Financing Receivables......................                - 0 -

8.  Accounts Receivable.........................................                4,004

9.  Other Assets................................................

    (Itemize amounts greater than 15% of Line 9)

           Intangible Asset - Goodwill .........................  86,813

                                                                               86,882

10. TOTAL ASSETS................................................              102,943

Page 1 of 3

OFFICE OF BANKS AND REAL ESTATE
BUREAU OF BANKS AND TRUST COMPANIES

CONSOLIDATED REPORT OF CONDITION
OF

BNY MIDWEST TRUST COMPANY
209 WEST JACKSON BOULEVARD
SUITE 700
CHICAGO, ILLINOIS 60606 

                                                                         THOUSANDS OF DOLLARS
                                                                         --------------------
                                  LIABILITIES
11. Accounts Payable........................................                    - 0 -

12. Taxes Payable...........................................                    - 0 -

13. Other Liabilities for Borrowed Money....................                   25,425

14. Other Liabilities.......................................

    (Itemize amounts greater than 15% of Line 14)

           Reserve for Taxes..................................3,128
           Taxes due to Parent Company........................1,923
           Accrued Expenses...................................1,058
                                                                                6,156

15. TOTAL LIABILITIES                                                          31,581
                            EQUITY CAPITAL

16. Preferred Stock.........................................                    - 0 -

17. Common Stock............................................                    2,000

18. Surplus.................................................                   62,130

19. Reserve for Operating Expenses..........................                    - 0 -

20. Retained Earnings (Loss)................................                    7,232

21. TOTAL EQUITY CAPITAL....................................                   71,362

22. TOTAL LIABILITIES AND EQUITY CAPITAL....................                  102,943

Page 2 of 3
I, Robert L. De Paola, Vice President
(Name and Title of Officer Authorized to Sign Report)

of BNY Midwest Trust Company certify that the information contained in this statement is accurate to the best of my knowledge and belief. I understand that submission of false information with the intention to deceive the Commissioner or his Administrative officers is a felony.

Robert L. Depaola
(Signature of Officer Authorized to Sign Report)

Sworn to and subscribed before me is 13th day of February, 2002. My Commission expires May 15, 2003.

Joseph A. Giacobino, Notary Public

(Notary Seal)

Person to whom Supervisory Staff should direct questions concerning this report. 

    Christine Anderson                          (212) 503-4204
----------------------------       --------------------------------------
           Name                          Telephone Number (Extension)

Page 3 of 3

EXHIBIT 25.2

FORM T-2

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF ELIGIBILITY
UNDER THE TRUST INDENTURE ACT OF 1939 OF AN
INDIVIDUAL DESIGNATED TO ACT AS TRUSTEE

CHECK IF AN APPLICATION TO DETERMINE
ELIGIBILITY OF A TRUSTEE PURSUANT TO
SECTION 305(b)(2) / /

DANIEL G. DONOVAN
(Name of trustee)

2 North LaSalle Street
Suite 1020
Chicago, Illinois 60602

000-00-0000 (Business address: street,
(Social Security Number) city state and zip code)

COMMONWEALTH EDISON COMPANY
(Exact name of obligor as specified in its charter) 

Illinois                                              36-0938600
(State or other jurisdiction of                       (I.R.S. employer
incorporation or organization)                        identification no.)

37th Floor
10 South Dearborn Street
Post Office Box 805379
Chicago, Illinois                                     60680
(Address of principal executive offices)              (Zip code)

                           ---------------------------

First Mortgage 6.15% Bonds, Series 98 due March 15, 2012
(Title of the indenture securities)

1. (a) AFFILIATIONS WITH OBLIGOR.

IF THE OBLIGOR IS AN AFFILIATE OF THE TRUSTEE, DESCRIBE EACH SUCH
AFFILIATION.

None. (see Note on page 3.)

(b) TRUSTEESHIPS UNDER OTHER INDENTURES.

IF THE TRUSTEE IS TRUSTEE UNDER ANOTHER INDENTURE UNDER WHICH ANY OTHER SECURITIES, OR CERTIFICATES OF INTEREST OR PARTICIPATION IN ANY OTHER SECURITIES, OF THE OBLIGOR ARE OUTSTANDING, FILE A COPY OF EACH SUCH INDENTURE AS AN EXHIBIT AND FURNISH THE FOLLOWING INFORMATION:

(a) TITLE OF THE SECURITIES OUTSTANDING UNDER EACH SUCH OTHER INDENTURE.

Not applicable.

(b) A BRIEF STATEMENT OF THE FACTS RELIED UPON BY THE TRUSTEE AS A BASIS FOR THE CLAIM THAT NO CONFLICTING INTEREST WITHIN THE MEANING OF SECTION 310(b)(1) OF THE ACT ARISES AS A RESULT OF THE TRUSTEESHIP UNDER SUCH OTHER INDENTURE, INCLUDING A STATEMENT AS TO HOW THE INDENTURE SECURITIES WILL RANK AS COMPARED WITH THE SECURITIES ISSUED UNDER SUCH OTHER INDENTURE.

Not applicable.

11. LIST OF EXHIBITS.

None.

NOTE

Inasmuch as this Form T-2 is filed prior to the ascertainment by the Trustee of all facts on which to base a responsive answer to Item 1, the answer to said Item is based on incomplete information.

Item 1 may, however, be considered as correct unless amended by an
amendment to this Form T-2.

SIGNATURE

Pursuant to the requirements of the Trust Indenture Act of 1939, I, Daniel G. Donovan have signed this statement of eligibility in the City of Chicago and State of Illinois, on the 6th day of September, 2002. 

   /s/ DANIEL G. DONOVAN
----------------------------
Name:  DANIEL G. DONOVAN

Exhibit 99.1

LETTER OF TRANSMITTAL

Commonwealth Edison Company

OFFER TO EXCHANGE ITS FIRST MORTGAGE 6.15% BONDS, SERIES 98 DUE MARCH 15, 2012, WHICH HAVE BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, FOR ANY AND ALL OF ITS ISSUED AND OUTSTANDING FIRST MORTGAGE 6.15% BONDS, SERIES 98 DUE MARCH 15, 2012

PURSUANT TO THE PROSPECTUS DATED __________, 2002

THE EXCHANGE OFFER WILL EXPIRE AT 5:00 P.M., NEW YORK CITY TIME, ON ________, 2002, UNLESS EXTENDED (THE "EXPIRATION DATE"). TENDERS MAY BE WITHDRAWN PRIOR TO 5:00 P.M., NEW YORK CITY TIME, ON THE EXPIRATION DATE. 

                  The Bank of New York, as Exchange Agent


BY REGISTERED OR CERTIFIED               BY HAND BEFORE 4:30 P.M.:        BY HAND AFTER 4:30 P.M. OR BY OVERNIGHT
            MAIL:                                                                         COURIER:

     The Bank of New York,                The Bank of New York                      The Bank of New York
       as Exchange Agent               Corporate Trust Operations               Corporate Trust Operations
      The Bank of New York                Reorganization Unit                       Reorganization Unit
   Corporate Trust Operations         15 Broad Street, 16th Floor              15 Broad Street, 16th Floor
      Reorganization Unit                 New York, NY 10007                     New York, New York 10007
  15 Broad Street, 16th Floor                                                   Facsimile: 212-235-[_____]
    New York, New York 10007                                                    Telephone: 212-235-[_____]
                                                                             Attention: [___________________]

Delivery of this instrument to an address other than as set forth above, or transmission of instructions other than as set forth above, will not constitute a valid delivery.

The undersigned acknowledges that he or she has received and reviewed the Prospectus, dated _________, 2002 (the "Prospectus"), of Commonwealth Edison Company, an Illinois corporation (the "Company"), and this Letter of Transmittal, which together constitute the Company's offer (the "Exchange Offer") to exchange up to $600,000,000 aggregate principal amount of the Company's First Mortgage 6.15% Bonds, Series 98 Due March 15, 2012 (the Exchange Bonds"), which have been registered under the Securities Act of 1933, as amended (the "Securities Act"), for a like principal amount of the Company's issued and outstanding First Mortgage 6.15% Bonds, Series 98 Due March 15, 2012 (the "Outstanding Bonds"), which have not been so registered.

For each Outstanding Bond accepted for exchange, the registered holder of such Outstanding Bond (collectively with all other registered holders of Outstanding Bonds, the "Holders") will receive an Exchange Bond having a principal amount equal to that of the surrendered Outstanding Bond. Registered

holders of Exchange Bonds on the relevant record date for the first interest payment date following the consummation of the Exchange Offer will receive interest accruing from the most recent date to which interest has been paid or, if no interest has been paid, from March 13, 2002. Outstanding Bonds accepted for exchange will cease to accrue interest from and after the date of consummation of the Exchange Offer. Accordingly, Holders whose Outstanding Bonds are accepted for exchange will not receive any payment in respect of accrued interest on such Outstanding Bonds otherwise payable on any interest payment date the record date for which occurs on or after consummation of the Exchange Offer.

This Letter of Transmittal is to be completed by a Holder of Outstanding Bonds if either certificates for such Outstanding Bonds are available to be forwarded herewith or tendered by book-entry transfer to the account maintained by the Exchange Agent at The Depository Trust Company (the "Book-Entry Transfer Facility") pursuant to the procedures set forth in "The Exchange Offer--Procedures for Tendering Outstanding Bonds" section of the Prospectus. Holders of Outstanding Bonds whose certificates are not immediately available, or who are unable to deliver their certificates or confirmation of the book-entry tender of their Outstanding Bonds into the Exchange Agent's account at the Book-Entry Transfer Facility (a "Book-Entry Confirmation") and all other documents required by this Letter of Transmittal to the Exchange Agent on or prior to the Expiration Date, must tender their Outstanding Bonds according to the guaranteed delivery procedures set forth in "The Exchange Offer--Guaranteed Delivery Procedures" section of the Prospectus. See Instruction 1. Delivery of documents to the Book-Entry Transfer Facility does not constitute delivery to the Exchange Agent.

The undersigned has completed the appropriate boxes below and signed this Letter of Transmittal to indicate the action the undersigned desires to take with respect to the Exchange Offer.

PLEASE READ THE ACCOMPANYING INSTRUCTIONS CAREFULLY

Ladies and Gentlemen:

Upon the terms and subject to the conditions of the Exchange Offer, the undersigned hereby tenders to the Company the aggregate principal amount of Outstanding Bonds indicated below. Subject to, and effective upon, the acceptance for exchange of the Outstanding Bonds tendered hereby, the undersigned hereby sells, assigns and transfers to, or upon the order of, the Company all right, title and interest in and to such Outstanding Bonds as are being tendered hereby.

The undersigned hereby represents and warrants that the undersigned has full power and authority to tender, sell, assign and transfer the Outstanding Bonds tendered hereby and that the Company will acquire good and unencumbered title thereto, free and clear of all liens, restrictions, charges and encumbrances and not subject to any adverse claim when the same are accepted by the Company. The undersigned hereby further represents that any Exchange Bonds acquired in exchange for Outstanding Bonds tendered hereby will have been acquired in the ordinary course of business of the person receiving such Exchange Bonds, whether or not such person is the undersigned, that neither the Holder of such Outstanding Bonds nor any such other person has an arrangement or understanding with any person to participate in a distribution of such Exchange Bonds and that neither the Holder of such Outstanding Bonds nor any such other person is an "affiliate" (as defined in Rule 405 under the Securities Act) of the Company.

The undersigned also acknowledges that this Exchange Offer is being made in reliance on interpretations by the staff of the Securities and Exchange Commission (the "SEC"), as set forth in no-action letters issued to third parties, that the Exchange Bonds issued pursuant to the Exchange Offer in exchange for the Outstanding Bonds may be offered for resale, resold and otherwise transferred by a Holder thereof (other than a Holder that is an "affiliate" of the Company within the meaning of Rule 405

under the Securities Act) without compliance with the registration and prospectus delivery provisions of the Securities Act, provided that such Exchange Bonds are acquired in the ordinary course of such Holder's business and such Holder has no arrangement with any person to participate in a distribution of such Exchange Bonds. However, the SEC has not considered the Exchange Offer in the context of a no-action letter and there can be no assurance that the staff of the SEC would make a similar determination with respect to the Exchange Offer as in other circumstances. If the undersigned is not a broker-dealer, the undersigned represents that it is not engaged in, and does not intend to engage in, a distribution of Exchange Bonds and has no arrangement or understanding to participate in a distribution of Exchange Bonds. If any Holder is an affiliate of the Company, is engaged in or intends to engage in, or has any arrangement or understanding with any person to participate in, a distribution of the Exchange Bonds to be acquired pursuant to the Exchange Offer, such Holder could not rely on the applicable interpretations of the staff of the SEC and must comply with the registration and prospectus delivery requirements of the Securities Act in connection with any resale transaction. If the undersigned is a broker-dealer that will receive Exchange Bonds for its own account in exchange for Outstanding Bonds that were acquired as a result of market-making activities or other trading activities, it acknowledges that it will deliver a prospectus meeting the requirements of the Securities Act in connection with any resale of such Exchange Bonds. However, by so acknowledging and by delivering a prospectus, the undersigned will not be deemed to admit that it is an "underwriter" within the meaning of the Securities Act.

The undersigned will, upon request, execute and deliver any additional documents deemed by the Company to be necessary or desirable to complete the sale, assignment and transfer of the Outstanding Bonds tendered hereby. All authority conferred or agreed to be conferred in this Letter of Transmittal and every obligation of the undersigned hereunder shall be binding upon the successors, assigns, heirs, executors, administrators, trustees in bankruptcy and legal representatives of the undersigned and shall not be affected by, and shall survive, the death or incapacity of the undersigned. This tender may be withdrawn only in accordance with the procedures set forth in "The Exchange Offer--Withdrawal Rights" section of the Prospectus.

Unless otherwise indicated herein in the box entitled "Special Issuance Instructions" herein, please issue the Exchange Bonds (and, if applicable, substitute certificates representing Outstanding Bonds for any Outstanding Bonds not exchanged) in the name of the undersigned or, in the case of a book-entry delivery of Outstanding Bonds, please credit the account indicated below maintained at the Book-Entry Transfer Facility. Similarly, unless otherwise indicated under the box entitled "Special Delivery Instructions" herein, please send the Exchange Bonds (and, if applicable, substitute certificates representing Outstanding Bonds for any Outstanding Bonds not exchanged) to the undersigned at the address shown in the box herein entitled "Description of Outstanding Bonds Delivered."

THE UNDERSIGNED, BY COMPLETING THE BOX BELOW ENTITLED "DESCRIPTION OF OUTSTANDING BONDS DELIVERED" AND SIGNING THIS LETTER, WILL BE DEEMED TO HAVE TENDERED OUTSTANDING BONDS AS SET FORTH IN SUCH BOX.

List below the Outstanding Bonds to which this Letter of Transmittal relates. If the space provided below is inadequate, the certificate numbers and principal amount of Outstanding Bonds should be listed on a separate signed schedule affixed hereto. 

                   DESCRIPTION OF OUTSTANDING BONDS DELIVERED

----------------------------------------- ------------------- ---------------------- ----------------------

Name(s) and Address of Registered         Certificate         Aggregate Principal    Principal Amount
Holder(s) (Please fill-in, if blank)      Number(s)*          Amount                 Tendered**
----------------------------------------- ------------------- ---------------------- ----------------------

--------------------------------------------------------------------------------------------------------

--------------------------------------------------------------------------------------------------------

--------------------------------------------------------------------------------------------------------

--------------------------------------------------------------------------------------------------------

--------------------------------------------------------------------------------------------------------
                       Totals:
--------------------------------------------------------------------------------------------------------

* Need not be completed if Outstanding Bonds are being tendered by book-entry transfer.

** Unless otherwise indicated in this column, a holder will be deemed to have tendered ALL of the Outstanding Bonds represented by the listed certificates. See Instruction 2. Outstanding Bonds tendered hereby must be in denominations of principal amount of $1,000 and any integral multiple thereof. See Instruction 1.

[ ] CHECK HERE IF TENDERED OUTSTANDING BONDS ARE BEING DELIVERED BY BOOK-ENTRY TRANSFER MADE TO THE ACCOUNT MAINTAINED BY THE EXCHANGE AGENT WITH THE BOOK-ENTRY TRANSFER FACILITY AND COMPLETE THE FOLLOWING:

Name of Tendering Institution
Account Number Transaction Code Number

[ ] CHECK HERE IF TENDERED OUTSTANDING BONDS ARE BEING DELIVERED PURSUANT TO A NOTICE OF GUARANTEED DELIVERY PREVIOUSLY SENT TO THE EXCHANGE AGENT AND COMPLETE THE FOLLOWING:

Name of Registered Holder
Window Ticket Number (if any)
Date of Execution of Notice of Guaranteed Delivery Name of Institution Which Guaranteed Delivery

If Delivered by Book-Entry Transfer, Complete the Following:

Account Number Transaction Code Number

[ ] CHECK HERE IF YOU ARE A BROKER-DEALER AND WISH TO RECEIVE ADDITIONAL COPIES OF THE PROSPECTUS AND ANY AMENDMENTS OR SUPPLEMENTS THERETO. (UNLESS OTHERWISE SPECIFIED, 10 ADDITIONAL COPIES WILL BE FURNISHED.)

Name

Address 

               SPECIAL ISSUANCE INSTRUCTIONS                              SPECIAL DELIVERY INSTRUCTIONS
                (See Instructions 3 and 4)                                  (See Instructions 3 and 4)
To be completed ONLY if certificates for Outstanding Bonds   To be completed ONLY if certificates for Outstanding
not exchanged and/or Exchange Bonds are to be issued in      Bonds not exchanged and/or Exchange Bonds are to be
the name of someone other than the person or persons whose   sent to someone other than the person or persons whose
signature(s) appear(s) on this Letter of Transmittal below   signature(s) appear(s) on this Letter of Transmittal
or if Outstanding Bonds delivered by book-entry transfer     below or to such person or persons at an address other
which are not accepted for exchange are to be returned by    than shown in the box entitled "Description of Outstanding
credit to an account maintained at the Book-Entry Transfer   Bonds Delivered" on this Letter of Transmittal
Facility other than the account indicated above.             above.

Issue Exchange Bonds and/or Outstanding Bonds to:            Mail Exchange Bonds and/or Outstanding Bonds to:

Name:                                                        Name:
      -----------------------------------------------             -----------------------------------------------
         (Please Type or Print)                                       (Please Type or Print)

Address:                                                     Address:
         --------------------------------------------             -----------------------------------------------

-----------------------------------------------------        ----------------------------------------------------
                                        (Zip Code)                                              (Zip Code)

[ ] Credit unexchanged Outstanding Bonds delivered by book-entry transfer to the Book-Entry Transfer Facility account set forth below.

(Book-Entry Transfer Facility Account)

IMPORTANT: THIS LETTER OR A FACSIMILE HEREOF OR AN AGENT'S MESSAGE IN LIEU HEREOF (TOGETHER WITH THE CERTIFICATES FOR OUTSTANDING BONDS OR A BOOK-ENTRY CONFIRMATION AND ALL OTHER REQUIRED DOCUMENTS OR THE NOTICE OF GUARANTEED DELIVERY) MUST BE RECEIVED BY THE EXCHANGE AGENT PRIOR TO 5:00 P.M., NEW YORK CITY TIME, ON THE EXPIRATION DATE.

PLEASE READ THE ENTIRE LETTER OF TRANSMITTAL CAREFULLY BEFORE COMPLETING ANY BOX ABOVE

PLEASE SIGN HERE

(All Tendering Holders Must Complete This Letter of Transmittal And The Accompanying Substitute Form W-9) 

Dated:                                      , 2002
       -------------------------------------

X
  ------------------------------------------------------------------------------

X
  ------------------------------------------------------------------------------
                                  Signature(s)

Area Code and Telephone Number:
                                ------------------------------------------------

If a holder is tendering any Outstanding Bonds, this letter must be signed by the Holder(s) as the name(s) appear(s) on the certificate(s) for the Outstanding Bonds or by any person(s) authorized to become Holder(s) by endorsements and documents transmitted herewith. If signature is by a trustee, executor, administrator, guardian, officer or other person acting in a fiduciary or representative capacity, please set forth full title. See Instruction 3.

Name:
(Please Type or Print)

Capacity (full title):

Address:
Telephone:

SIGNATURE GUARANTEE (If required by Instruction 3)

Signature(s) Guarantees by an Eligible Institution:


(Authorized Signature)

(Title)

(Name and Firm)

Dated: , 2002

INSTRUCTIONS

FORMING PART OF THE TERMS AND CONDITIONS OF THE OFFER TO EXCHANGE THE FIRST MORTGAGE 6.15% BONDS, SERIES 98 DUE MARCH 15, 2012 OF COMMONWEALTH EDISON COMPANY, WHICH HAVE BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, FOR ANY AND ALL OF THE ISSUED AND OUTSTANDING FIRST MORTGAGE 6.15% BONDS, SERIES 98 DUE MARCH 15, 2012 OF COMMONWEALTH EDISON COMPANY.

1. DELIVERY OF THIS LETTER AND OUTSTANDING BONDS; GUARANTEED DELIVERY PROCEDURES.

This Letter of Transmittal is to be completed by Holders of Outstanding Bonds either if certificates are to be forwarded herewith or if tenders are to be made pursuant to the procedures for delivery by book-entry transfer set forth in "The Exchange Offer--Procedures for Tendering Outstanding Bonds" section of the Prospectus. Certificates for all physically tendered Outstanding Bonds, or Book-Entry Confirmation, as the case may be, as well as a properly completed and duly executed Letter of Transmittal (or a manually signed facsimile hereof) and any other documents required by this Letter of Transmittal, must be received by the Exchange Agent at the address set forth herein on or prior to the Expiration Date, or the tendering holder must comply with the guaranteed delivery procedures set forth below. Outstanding Bonds tendered hereby must be in denominations of principal amount of $1,000 and any integral multiple thereof.

Holders whose certificates for Outstanding Bonds are not immediately available or who cannot deliver their certificates and all other required documents to the Exchange Agent on or prior to the Expiration Date, or who cannot complete the procedure for book-entry transfer on a timely basis, may tender their Outstanding Bonds pursuant to the guaranteed delivery procedures set forth in "The Exchange Offer--Guaranteed Delivery Procedures" section of the Prospectus. Pursuant to those procedures, (i) such tender must be made through an Eligible Institution (as defined below), (ii) on or prior to 5:00 p.m., New York City time, on the Expiration Date, the Exchange Agent must receive from such Eligible Institution a properly completed and duly executed Letter of Transmittal (or a facsimile thereof) and Notice of Guaranteed Delivery, substantially in the form provided by the Company (by telegram, telex, facsimile transmission, mail or hand delivery), setting forth the name and address of the holder of Outstanding Bonds and the amount of Outstanding Bonds tendered, stating that the tender is being made thereby and guaranteeing that within three New York Stock Exchange ("NYSE") trading days after the date of execution of the Notice of Guaranteed Delivery, the certificates for all physically tendered Outstanding Bonds, in proper form for transfer, or a Book-Entry Confirmation, as the case may be, and any other documents required by this Letter of Transmittal will be deposited by the Eligible Institution with the Exchange Agent, and (iii) the certificates for all physically tendered Outstanding Bonds, in proper form for transfer, or Book-Entry Confirmation, as the case may be, and any other documents required by this Letter of Transmittal, are deposited by the Eligible Institution within three NYSE trading days after the date of execution of the Notice of Guaranteed Delivery.

The method of delivery of this Letter of Transmittal, the Outstanding Bonds and all other required documents is at the election and risk of the tendering Holders, but delivery will be deemed made only upon actual receipt or confirmation by the Exchange Agent. If Outstanding Bonds are sent by mail, it is suggested that the mailing be registered mail, properly insured, with return receipt requested, and made sufficiently in advance of the Expiration Date to permit delivery to the Exchange Agent prior to 5:00 p.m., New York City time, on the Expiration Date.

See "The Exchange Offer" section of the Prospectus.

2. PARTIAL TENDERS (NOT APPLICABLE TO HOLDERS WHO TENDER BY BOOK-ENTRY TRANSFER).

If less than all of the Outstanding Bonds evidenced by a submitted certificate are to be tendered, the tendering holder(s) should fill in the aggregate principal amount of Outstanding Bonds to be tendered in the box above entitled "Description of Outstanding Bonds -- Principal Amount Tendered." A reissued certificate representing the balance of nontendered Outstanding Bonds will be sent to such tendering Holder, unless otherwise provided in the appropriate box of this Letter of Transmittal, promptly after the Expiration Date. See Instruction 4. All of the Outstanding Bonds delivered to the Exchange Agent will be deemed to have been tendered unless otherwise indicated.

3. SIGNATURES ON THIS LETTER, BOND POWERS AND ENDORSEMENTS, GUARANTEE OF SIGNATURES.

If this Letter of Transmittal is signed by the Holder of the Outstanding Bonds tendered hereby, the signature must correspond exactly with the name as written on the face of the certificates without any change whatsoever.

If any tendered Outstanding Bonds are owned of record by two or more joint owners, all of such owners must sign this Letter of Transmittal.

If any tendered Outstanding Bonds are registered in different names on several certificates, it will be necessary to complete, sign and submit as many separate copies of this letter as there are different registrations of certificates.

When this Letter of Transmittal is signed by the Holder or Holders of the Outstanding Bonds specified herein and tendered hereby, no endorsements of certificates or separate bond powers are required. If however, the Exchange Bonds are to be issued, or any untendered Outstanding Bonds are to be reissued, to a person other than the Holder, then endorsements of any certificates transmitted hereby or separate bond powers are required. Signatures on such certificates(s) must be guaranteed by an Eligible Institution.

If this Letter of Transmittal is signed by a person other than the Holder or Holders of any certificate(s) specified herein, such certificate(s) must be endorsed or accompanied by appropriate bond powers, in either case signed exactly as the name or names of the Holder or Holders appear(s) on the certificate(s) and signatures on such certificate(s) must be guaranteed by an Eligible Institution.

If this Letter of Transmittal or any certificates or bond powers are signed by trustees, executors, administrators, guardians, attorneys-in-fact, officers of corporations or others acting in a fiduciary or representative capacity, such persons should so indicate when signing, and, unless waived by the Company, proper evidence satisfactory to the Company of their authority to so act must be submitted.

ENDORSEMENTS ON CERTIFICATES FOR OUTSTANDING BONDS OR SIGNATURES ON BOND POWERS REQUIRED BY THIS INSTRUCTION 3 MUST BE GUARANTEED BY A FINANCIAL INSTITUTION (INCLUDING MOST BANKS, SAVINGS AND LOAN ASSOCIATIONS AND BROKERAGE HOUSES) THAT IS A PARTICIPANT IN THE SECURITIES TRANSFER AGENTS MEDALLION PROGRAM, THE NEW YORK STOCK EXCHANGE MEDALLION SIGNATURE PROGRAM OR THE STOCK EXCHANGES MEDALLION PROGRAM (EACH, AN "ELIGIBLE INSTITUTION").

SIGNATURES ON THIS LETTER NEED NOT BE GUARANTEED BY AN ELIGIBLE INSTITUTION, PROVIDED THE OUTSTANDING BONDS ARE TENDERED: (I) BY A REGISTERED HOLDER OF OUTSTANDING BONDS (WHICH TERM, FOR PURPOSES OF THE

EXCHANGE OFFER, INCLUDES ANY PARTICIPANT IN THE BOOK-ENTRY TRANSFER FACILITY SYSTEM WHOSE NAME APPEARS ON A SECURITY POSITION LISTING AS THE HOLDER OF SUCH OUTSTANDING BONDS) WHO HAS NOT COMPLETED THE BOX ENTITLED "SPECIAL ISSUANCE INSTRUCTIONS" OR "SPECIAL DELIVERY INSTRUCTIONS" ON THIS LETTER OR (II) FOR THE ACCOUNT OF AN ELIGIBLE INSTITUTION.

4. SPECIAL ISSUANCE AND DELIVERY INSTRUCTIONS.

Tendering Holders of Outstanding Bonds should indicate in the applicable box the name and address to which Exchange Bonds issued pursuant to the Exchange Offer and/or substitute certificates evidencing Outstanding Bonds not exchanged are to be issued or sent, if different from the name or address of the person signing this Letter of Transmittal. In the case of issuance in a different name, the employer identification or social security number of the person named must also be indicated. Holders tendering Outstanding Bonds by book-entry transfer may request that Outstanding Bonds not exchanged be credited to such account maintained at the Book-Entry Transfer Facility as such Holder may designate hereon. If no such instructions are given, such Outstanding Bonds not exchanged will be returned to the name and address of the person signing this Letter of Transmittal.

5. TRANSFER TAXES.

The Company will pay all transfer taxes, if any, applicable to the transfer of Outstanding Bonds to it or its order pursuant to the Exchange Offer. If, however, Exchange Bonds and/or substitute Outstanding Bonds not exchanged are to be delivered to, or are to be registered or issued in the name of, any person other than the Holder of the Outstanding Bonds tendered hereby, or if tendered Outstanding Bonds are registered in the name of any person other than the person signing this Letter of Transmittal, or if a transfer tax is imposed for any reason other than the transfer of Outstanding Bonds to the Company or its order pursuant to the Exchange Offer, the amount of any such transfer taxes (whether imposed on the registered holder or any other persons) will be payable by the tendering Holder. If satisfactory evidence of payment of such taxes or exemption therefrom is not submitted herewith, the amount of such transfer taxes will be billed to such tendering Holder and the Exchange Agent will retain possession of an amount of Exchange Bonds with a face amount equal to the amount of such transfer taxes due by such tendering Holder pending receipt by the Exchange Agent of the amount of such taxes.

Except as provided in this Instruction 5, it will not be necessary for transfer tax stamps to be affixed to the Outstanding Bonds specified in this Letter of Transmittal.

6. WAIVER OF CONDITIONS.

The Company reserves the absolute right to waive satisfaction of any or all conditions enumerated in the Prospectus.

7. NO CONDITIONAL TENDERS.

No alternative, conditional, irregular or contingent tenders will be accepted. All tendering Holders of Outstanding Bonds, by execution of this Letter of Transmittal, shall waive any right to receive notice of the acceptance of their Outstanding Bonds for exchange.

Although the Company intends to notify Holders of defects or irregularities with respect to tenders of Outstanding Bonds, neither the Company, the Exchange Agent nor any other person shall incur any liability for failure to give any such notice.

8. MUTILATED, LOST, STOLEN OR DESTROYED OUTSTANDING BONDS.

Any Holder whose Outstanding Bonds have been mutilated, lost, stolen or destroyed should contact the Exchange Agent at the address indicated above for further instructions.

9. WITHDRAWAL OF TENDERS.

Tenders of Outstanding Bonds may be withdrawn at any time prior to 5:00 P.M., New York City time, on the Expiration Date. For a withdrawal to be effective, a written notice of withdrawal must be received by the Exchange Agent at one of the addresses set forth above. Any such notice of withdrawal must specify the name of the person having tendered the Outstanding Bonds to be withdrawn, identify the Outstanding Bonds to be withdrawn (including the principal amount of such Outstanding Bonds ), and (where certificates for Outstanding Bonds have been transmitted) specify the name in which such Outstanding Bonds are registered, if different from that of the withdrawing Holder. If certificates for Outstanding Bonds have been delivered or otherwise identified to the Exchange Agent, then prior to the release of such certificates the withdrawing Holder must also submit the serial numbers of the particular certificates to be withdrawn and a signed notice of withdrawal with signatures guaranteed by an Eligible Institution unless such Holder is an Eligible Institution in which case such guarantee will not be required. If Outstanding Bonds have been tendered pursuant to the procedure for book-entry transfer described above, any notice of withdrawal must specify the name and number of the account at the Book-Entry Transfer Facility to be credited with the withdrawn Outstanding Bonds and otherwise comply with the procedures of such facility. All questions as to the validity, form and eligibility (including time of receipt) of such notices will be determined by the Company, whose determination will be final and binding on all parties. Any Outstanding Bonds so withdrawn will be deemed not to have been validly tendered for exchange for purposes of the Exchange Offer. Any Outstanding Bonds which have been tendered for exchange but which are not exchanged for any reason will be returned to the Holder thereof without cost to such Holder (or, in the case of Outstanding Bonds tendered by book-entry transfer into the Exchange Agent's account at the Book-Entry Transfer Facility pursuant to the book-entry transfer procedures described above, such Outstanding Bonds will be credited to an account maintained with such Book-Entry Transfer Facility for the Outstanding Bonds) as soon as practicable after withdrawal, rejection of tender or termination of the Exchange Offer. Properly withdrawn Outstanding Bonds may be retendered by following one of the procedures set forth in "The Exchange Offer--Procedures for Tendering Outstanding Bonds" section of the Prospectus at any time on or prior to the Expiration Date.

10. REQUESTS FOR ASSISTANCE OR ADDITIONAL COPIES.

Questions relating to the procedure for tendering, as well as requests for additional copies of the Prospectus, this Letter of Transmittal and other related documents may be directed to the Exchange Agent at the address indicated above.

IMPORTANT TAX INFORMATION

Under current United States federal income tax law, a Holder of Exchange Bonds is required to provide the Company (as payor) with such Holder's correct taxpayer identification number ("TIN") on Substitute Form W-9 or otherwise establish a basis for exemption from backup withholding to prevent backup withholding on any Exchange Bonds delivered pursuant to the Exchange Offer and any payments received in respect of the Exchange Bonds . If a Holder of Exchange Bonds is an individual, the TIN is such holder's social security number. If the Company is not provided with the correct taxpayer identification number, a Holder of Exchange Bonds may be subject to a $50 penalty imposed by the Internal Revenue Service. Accordingly, each prospective Holder of Exchange Bonds to be issued pursuant to Special Issuance Instructions should complete the attached Substitute Form W-9. The Substitute Form W-9 need not be completed if the box entitled Special Issuance Instructions has not been completed.

Certain Holders of Exchange Bonds (including, among others, all corporations and certain foreign individuals) are not subject to these backup withholding and reporting requirements. Exempt prospective Holders of Exchange Bonds should indicate their exempt status on Substitute Form W-9. A foreign individual may qualify as an exempt recipient by submitting to the Company, through the Exchange Agent, a properly completed Internal Revenue Service Form W-8 BEN or Form W-8 ECI (which the Exchange Agent will provide upon request) signed under penalty of perjury, attesting to the Holder's exempt status. See the enclosed Guidelines for Certification of Taxpayer Identification Number on Substitute Form W-9 for additional instructions.

If backup withholding applies, the Company is required to withhold 30% of any payment made to the Holder of Exchange Bonds or other payee. Backup withholding is not an additional United States federal income tax. Rather, the United States federal income tax liability of persons subject to backup withholding will be reduced by the amount of tax withheld. If withholding results in an overpayment of taxes, a refund may be obtained from the Internal Revenue Service.

PURPOSE OF SUBSTITUTE FORM W-9

To prevent backup withholding on any Exchange Bonds delivered pursuant to the Exchange Offer and any payments received in respect of the Exchange Bonds, each prospective Holder of Exchange Bonds to be issued pursuant to Special Issuance Instructions should provide the Company, through the Exchange Agent, with either: (i) such prospective Holder's correct TIN by completing the form below, certifying that the TIN provided on Substitute Form W-9 is correct (or that such prospective Holder is awaiting a TIN) and that (A) such prospective Holder has not been notified by the Internal Revenue Service that he or she is subject to backup withholding as a result of a failure to report all interest or dividends or (B) the Internal Revenue Service has notified such prospective Holder that he or she is no longer subject to backup withholding; or
(ii) an adequate basis for exemption.

WHAT NUMBER TO GIVE THE EXCHANGE AGENT

The prospective Holder of Exchange Bonds to be issued pursuant to Special Issuance Instructions is required to give the Exchange Agent the TIN (e.g., social security number or employer identification number) of the prospective record owner of the Exchange Bonds . If the Exchange Bonds will be held in more than one name or are not held in the name of the actual owner, consult the enclosed Guidelines for Certification of Taxpayer Identification Number on Substitute Form W-9 for additional guidance regarding which number to report.

TO BE COMPLETED BY ALL TENDERING HOLDERS
(SEE IMPORTANT TAX INFORMATION)

PAYOR'S NAME: THE BANK OF NEW YORK 

--------------------------------------- ------------------------------------- ----------------------------------------

Substitute Form W-9                     Department of the Treasury            Payor's Request for Taxpayer
                                                                              Identification Number ("TIN") and
                                        Internal Revenue Service              Certification
--------------------------------------- ------------------------------------- ----------------------------------------

PART I--PLEASE PROVIDE
YOUR TIN IN THE BOX AT               TIN:
RIGHT OR INDICATE THAT                   -------------------------------
YOU APPLIED FOR A TIN                 Social Security Number or
AND CERTIFY BY SIGNING                Employer Identification Number
AND DATING BELOW.                     TIN Applied for [_]



--------------------------------------- ------------------------------------------------------------------------------

PART II--CERTIFICATION--UNDER PENALTIES OF PERJURY, I CERTIFY THAT:

(1) The number shown on this form is my correct Taxpayer Identification Number
(or I am waiting for a number to be issued to me);

(2) I am not subject to backup withholding either because: (a) I am exempt from
backup withholding, or (b) I have not been notified by the Internal Revenue
Service (the "IRS") that I am subject to backup withholding as a result of a
failure to report all interest or dividends, or (c) the IRS has notified me that
I am no longer subject to backup withholding; and

(3)    any other information provided on this form is true and correct.
----------------------------------------------------------------------------------------------------------------------

Signature:                                                    Date:
           ------------------------------------------              ---------------------------------------------------
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You must cross out item (2) of the above certification if you have been notified by the IRS that you are subject to backup withholding because of underreporting of interest or dividends on your tax return and you have not been notified by the IRS that you are no longer subject to backup withholding.

NOTE: FAILURE BY A PROSPECTIVE HOLDER OF EXCHANGE BONDS TO BE ISSUED PURSUANT TO THE SPECIAL ISSUANCE INSTRUCTIONS ABOVE TO COMPLETE AND RETURN THIS FORM MAY RESULT IN BACKUP WITHHOLDING OF 30% OF THE EXCHANGE BONDS DELIVERED TO YOU PURSUANT TO THE EXCHANGE OFFER AND ANY PAYMENTS RECEIVED BY YOU IN RESPECT OF THE EXCHANGE BONDS. PLEASE REVIEW THE ENCLOSED GUIDELINES FOR CERTIFICATION OF TAXPAYER IDENTIFICATION NUMBER ON SUBSTITUTE FORM W-9 FOR ADDITIONAL DETAILS.

YOU MUST COMPLETE THE FOLLOWING CERTIFICATE IF YOU CHECKED
THE BOX IN PART 1 OF SUBSTITUTE FORM W-9

CERTIFICATE OF AWAITING TAXPAYER IDENTIFICATION NUMBER

I certify under penalties of perjury that a taxpayer identification number has not been issued to me, and either (a) I have mailed or delivered an application to receive a taxpayer identification number to the appropriate Internal Revenue Service Center or Social Security Administration Office or (b) I intend to mail or deliver an application in the near future. I understand that if I do not provide a taxpayer identification number by the time of the exchange, 30% of all reportable payments made to me thereafter will be withheld until I provide a number.

Signature Date

Exhibit 99.2

FORM OF NOTICE OF GUARANTEED DELIVERY

Commonwealth Edison Company

OFFER TO EXCHANGE ITS FIRST MORTGAGE 6.15% BONDS, SERIES 98 DUE MARCH 15, 2012, WHICH HAVE BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, FOR ANY AND ALL OF ITS ISSUED AND OUTSTANDING FIRST MORTGAGE 6.15% BONDS, SERIES 98 DUE MARCH 15, 2012.

PURSUANT TO THE PROSPECTUS DATED _________, 2002

THE EXCHANGE OFFER WILL EXPIRE AT 5:00 P.M., NEW YORK CITY TIME, ON __________, 2002, UNLESS EXTENDED (THE "EXPIRATION DATE"). TENDERS MAY BE WITHDRAWN PRIOR TO 5:00 P.M., NEW YORK CITY TIME, ON THE EXPIRATION DATE.

As set forth in the Prospectus dated _______, 2002 (the "Prospectus") under the caption "The Exchange Offer--Guaranteed Delivery Procedures" and the accompanying Letter of Transmittal (the "Letter of Transmittal") and Instruction 1 thereto, this form, or one substantially equivalent hereto, must be used to accept the Exchange Offer if certificates representing the First Mortgage 6.15% Bonds, Series 98 due March 15, 2012 (the "Outstanding Bonds"), of Commonwealth Edison Company, an Illinois corporation (the "Company"), are not immediately available or if the procedure for book-entry transfer cannot be completed on a timely basis or time will not permit a Holder's certificates or other required documents to reach the Exchange Agent on or prior to the Expiration Date. Such form may be delivered by hand, overnight courier, facsimile transmission or mail to the Exchange Agent and must include a guarantee by an Eligible Institution (as defined in the Letter of Transmittal) unless such form is submitted on behalf of an Eligible Institution. Capitalized terms used and not defined herein have the respective meanings ascribed to them in the Prospectus.

The Exchange Agent is The Bank of New York 

BY REGISTERED OR CERTIFIED MAIL:         BY HAND BEFORE 4:30 P.M.:        BY HAND AFTER 4:30 P.M. OR BY OVERNIGHT
                                                                                         COURIER:

     The Bank of New York,                    The Bank of New York                 The Bank of New York
       as Exchange Agent                   Corporate Trust Operations          Corporate Trust Operations
      The Bank of New York                    Reorganization Unit                  Reorganization Unit
   Corporate Trust Operations             15 Broad Street, 16th Floor        15 Broad Street, 16th Floor
      Reorganization Unit                      New York, NY 10007               New York, New York 10007
  15 Broad Street, 16th Floor                                                   Facsimile: 212-235-[_____]
    New York, New York 10007                                                    Telephone: 212-235-[_____]
                                                                            Attention: [___________________]

Delivery of this instrument to an address other than as set forth above, or transmission of instructions other than as set forth above, will not constitute a valid delivery.

This form is not to be used to guarantee signatures. If a signature on a Letter of Transmittal is required to be guaranteed by an "Eligible Institution" under the instructions thereto, such signature guarantee must appear in the applicable space provided in the signature box on the Letter of Transmittal.

Ladies & Gentlemen:

Upon the terms and subject to the conditions set forth in the Prospectus and the accompanying Letter of Transmittal, receipt of which is hereby acknowledged, the undersigned hereby tenders to the Company $ ________ principal amount of Outstanding Bonds, pursuant to the guaranteed delivery procedures set forth in the Prospectus and accompanying Letter of Transmittal. 

Certificate                                 Principal Amount
Number(s)                                   Tendered

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If Outstanding Bonds will be tendered by book-entry transfer to The Depositary Trust Company (the "DTC"), provide account number (as applicable).

Account No. ___________________________

The undersigned authorizes the Exchange Agent to deliver this Notice of Guaranteed Delivery to the Company and BNY Midwest Trust Company, as Trustee with respect to the Outstanding Bonds tendered pursuant to the Exchange Offer.

All authority conferred or agreed to be conferred by this Notice of Guaranteed Delivery shall not be affected by, and shall survive, the death or incapacity of the undersigned, and every obligation of the undersigned under this Notice of Guaranteed Delivery shall be binding upon the heirs, executors, administrators, trustees in bankruptcy, personal and legal representatives, successors and assigns of the undersigned.

SIGN HERE

Signature(s) of Registered Holder(s) or Authorized Signatory

Name(s) of Registered Holder(s)
(Please Type or Print)

Address

Zip Code

Area code and Telephone Number

Dated:__________________________________________________________ , 2002

2

GUARANTEE
(Not to be Used for Signature Guarantees)

The undersigned, a member firm of a registered national securities exchange or of the National Association of Securities Dealers, Inc., or a commercial bank or trust company having an office in the United States, hereby
(a) represents that the above-named person(s) has a net long position in the Outstanding Bonds tendered hereby within the meaning of Rule 14e-4 under the Securities Exchange Act of 1934, as amended, (b) represents that such tender of Outstanding Bonds complies with Rule 14e-4 and (c) guarantees delivery to the Exchange Agent of certificates representing the Outstanding Bonds tendered hereby, in proper form for transfer, or confirmation of book-entry transfer of such Outstanding Bonds into the Exchange Agent's account at DTC, with a properly completed and duly executed Agent's Message (as defined in the Letter of Transmittal) or Letter of Transmittal, as the case may be, with any required signature guarantees and any other documents required by the Letter of Transmittal, within three Business Days after the Expiration Date. 

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Name of Firm                                Title

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Authorized Signature                        Name (Please Type or Print)

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Address                                     Dated:______________ , 2002

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Area Code and Telephone Number

NOTE: DO NOT SEND CERTIFICATES REPRESENTING OUTSTANDING BONDS WITH THIS FORM. CERTIFICATES FOR OUTSTANDING BONDS MUST BE SENT WITH YOUR LETTER OF TRANSMITTAL.