# EDGAR Filing Document

**Accession Number:** 0001109357
**File Stem:** 0001104659-23-022633
**Filing Date:** 2023-2
**Character Count:** 169745
**Document Hash:** 24598f140ecfd98e84a13119f4a4010f
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001104659-23-022633.hdr.sgml**: 20230216

**ACCESSION NUMBER**: 0001104659-23-022633

**CONFORMED SUBMISSION TYPE**: 424B5

**PUBLIC DOCUMENT COUNT**: 2

**FILED AS OF DATE**: 20230216

**DATE AS OF CHANGE**: 20230216

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** EXELON CORP
- **CENTRAL INDEX KEY:** 0001109357
- **STANDARD INDUSTRIAL CLASSIFICATION:** ELECTRIC & OTHER SERVICES COMBINED [4931]
- **IRS NUMBER:** 232990190
- **STATE OF INCORPORATION:** PA
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** 424B5
- **SEC ACT:** 1933 Act
- **SEC FILE NUMBER:** 333-266487
- **FILM NUMBER:** 23637319

**BUSINESS ADDRESS:**
- **STREET 1:** PO BOX 805398
- **CITY:** CHICAGO
- **STATE:** IL
- **ZIP:** 60680-5398
- **BUSINESS PHONE:** 3123947399

**MAIL ADDRESS:**
- **STREET 1:** PO BOX 805398
- **CITY:** CHICAGO
- **STATE:** IL
- **ZIP:** 60680-5398

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** EXELON Corp
- **DATE OF NAME CHANGE:** 20180928

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** EXELON CORP
- **DATE OF NAME CHANGE:** 20000315

[**TABLE OF CONTENTS**](#TOC)

The information in this preliminary prospectus supplement is not complete and may be changed. This preliminary prospectus supplement and the accompanying prospectus are not an offer to sell these securities and we are not soliciting an offer to buy these securities in any jurisdiction where the offer or sale is not permitted.

#### File Pursuant to rule 424(b)(5)

#### Registration No. 333-266487

#### Subject to Completion Preliminary Prospectus Supplement dated February 16, 2023

#### PROSPECTUS SUPPLEMENT (To Prospectus Dated August 3, 2022)

### $![[MISSING IMAGE: lg_exelonsm-4clr.jpg]](lg_exelonsm-4clr.jpg)

### Exelon Corporation

### $% Notes due 20
Exelon Corporation ("Exelon") is offering $ of its % notes due 20 (the "20 notes"), $ of its % notes due 20 (the "20 notes"), and $ of its % notes due 20 (the "20 notes" and, collectively with the 20 notes and the 20 notes, the "notes").

The 20 notes will mature on March 15, 20 , the 20 notes will mature on March 15, 20 , and the 20 notes will mature on March 15, 20 . We will pay interest on the 20 notes, the 20 notes, and the 20 notes semi-annually on March 15 and September 15 of each year, beginning on September 15, 2023.

We may also redeem any series of the notes at any time prior to maturity, in whole or in part, upon at least 10 days' and not more than 60 days' notice, at the redemption prices described in this prospectus supplement under "Description of the Notes — Optional Redemption."

The notes will be our direct unsecured general obligations and will rank equally with all of our existing and future unsecured and unsubordinated debt.

 **Investing in our notes involves certain risks. You should carefully read this prospectus supplement and the accompanying base prospectus, including the documents incorporated by reference herein and therein, before you make your investment decision. See the "Risk Factors" section beginning on page [S-9](#tRIFA1) of this prospectus supplement, as well as under "Risk Factors" in our Annual Report on Form 10-K for the year ended December 31, 2022, which is incorporated by reference herein, for more information.** 

---

| | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|
| | **Price to <br> Public<sup>(1)</sup>**  | **Price to <br> Public<sup>(1)</sup>**  | **Underwriting <br> Discount**  | **Underwriting <br> Discount**  | **Proceeds, before <br> expenses, to Exelon**  | **Proceeds, before <br> expenses, to Exelon**  |
| | **Per Note**  | **Total**  | **Per Note**  | **Total**  | **Per Note**  | **Total**  |
| Per 20 note  | &nbsp;&nbsp;% |  | $% |  | $% | $|
| Per 20 note  | &nbsp;&nbsp;% |  | $% |  | $% | $|
| Per 20 note  | &nbsp;&nbsp;% |  | $% |  | $% | $|

---

(1) Plus accrued interest from , 2023, if settlement occurs after that date.

 **Neither the Securities and Exchange Commission (the "SEC") nor any state securities commission has approved or disapproved of these securities or determined if this prospectus supplement or the accompanying prospectus is truthful or complete. Any representation to the contrary is a criminal offense.** 

The notes are expected to be delivered in book-entry form only through the facilities of The Depository Trust Company ("DTC"), including Clearstream Banking S.A. ("Clearstream"), and/or Euroclear Bank S.A./ N.V. ("Euroclear"), against payment in New York, New York on or about , 2023.

 *Joint Book Runners* 

### Barclays Citigroup Goldman Sachs & Co. LLC J.P. Morgan Morgan Stanley

#### MUFG PNC Capital Markets LLC SMBC Nikko Wells Fargo Securities
 *Senior Co- Managers* 

#### Loop Capital Markets Siebert Williams Shank Huntington Capital Markets

#### The date of this prospectus supplement is , 2023.

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[**TABLE OF CONTENTS**](#TOC)

 **We urge you to carefully read this prospectus supplement and the accompanying prospectus, which describe the terms of the offering of the notes, before you make your investment decision. This prospectus supplement, the accompanying prospectus and any related free writing prospectus required to be filed with the Securities and Exchange Commission (SEC) that we prepare or authorize contain and incorporate by reference information that you should consider when making your investment decisions. We have not, and the underwriters have not, authorized anyone else to provide you with different information. If anyone provides you with different or inconsistent information, you should not rely on it. We are not, and the underwriters are not, making an offer to sell these notes in any jurisdiction where the offer or sale is not permitted. You should not assume that the information appearing in this prospectus supplement, the accompanying prospectus and any related free writing prospectus is accurate as of any date other than the date on the front of those documents or that the information incorporated by reference is accurate as of any date other than the date that the document incorporated by reference was filed with the SEC. Our business, financial condition, results of operations and prospects may have changed since those respective dates.** 

#### **TABLE OF CONTENTS**

#### Prospectus Supplement

---

| | |
|:---|:---|
| | **Page**  |
| [ABOUT THIS PROSPECTUS SUPPLEMENT](#tATPS1)  | [S-1](#tATPS1) |
| [FORWARD LOOKING STATEMENTS](#tFLS1)  | [S-3](#tFLS1) |
| [SUMMARY](#tSUM1)  | [S-4](#tSUM1) |
| [SUMMARY FINANCIAL INFORMATION](#tSFI1)  | [S-5](#tSFI1) |
| [THE OFFERING](#tTHOF1)  | [S-6](#tTHOF1) |
| [RISK FACTORS](#tRIFA1)  | [S-9](#tRIFA1) |
| [USE OF PROCEEDS](#tUOP1)  | [S-10](#tUOP1) |
| [CAPITALIZATION](#tCAP1)  | [S-11](#tCAP1) |
| [DESCRIPTION OF THE NOTES](#tDOTN1)  | [S-12](#tDOTN1) |
| [MATERIAL UNITED STATES FEDERAL INCOME TAX CONSIDERATIONS](#tMUSF1)  | [S-21](#tMUSF1) |
| [UNDERWRITING (CONFLICTS OF INTEREST)](#tUCOI1)  | [S-26](#tUCOI1) |
| [LEGAL MATTERS](#tLEMA1)  | [S-32](#tLEMA1) |
| [EXPERTS](#tEXP1)  | [S-32](#tEXP1) |
| [WHERE YOU CAN FIND MORE INFORMATION](#tWYCF1)  | [S-32](#tWYCF1) |
| [DOCUMENTS INCORPORATED BY REFERENCE](#tDIBR1)  | [S-32](#tDIBR1) |

---

#### Prospectus

---

| | |
|:---|:---|
| [ABOUT THIS PROSPECTUS](#tATP2)  | [1](#tATP2) |
| [FORWARD-LOOKING STATEMENTS](#tFOST2)  | [1](#tFOST2) |
| [RISK FACTORS](#tRIFA2)  | [2](#tRIFA2) |
| [EXELON CORPORATION](#tEXCO2)  | [2](#tEXCO2) |
| [COMMONWEALTH EDISON COMPANY](#tCEC2)  | [2](#tCEC2) |
| [PECO ENERGY COMPANY](#tPEC2)  | [2](#tPEC2) |
| [BALTIMORE GAS AND ELECTRIC COMPANY](#tBGAE2)  | [3](#tBGAE2) |
| [POTOMAC ELECTRIC POWER COMPANY](#tPEPC2)  | [3](#tPEPC2) |
| [DELMARVA POWER & LIGHT COMPANY](#tDPLC2)  | [3](#tDPLC2) |
| [ATLANTIC CITY ELECTRIC COMPANY](#tACEC2)  | [3](#tACEC2) |
| [USE OF PROCEEDS](#tUOP2)  | [3](#tUOP2) |
| [DESCRIPTION OF SECURITIES](#tDOS2)  | [3](#tDOS2) |

---

S-i

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---

| | |
|:---|:---|
| [PLAN OF DISTRIBUTION](#tPOD2)  | [3](#tPOD2) |
| [LEGAL MATTERS](#tLEMA2)  | [5](#tLEMA2) |
| [EXPERTS](#tEXP2)  | [5](#tEXP2) |
| [WHERE YOU CAN FIND MORE INFORMATION](#tWYCF2)  | [6](#tWYCF2) |
| [DOCUMENTS INCORPORATED BY REFERENCE](#tDIBR2)  | [6](#tDIBR2) |

---

S-ii

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#### ABOUT THIS PROSPECTUS SUPPLEMENT
This prospectus supplement and the accompanying prospectus contain information about Exelon and the notes offered hereby. This prospectus supplement and the accompanying prospectus also refer to information contained in other documents that we file with the SEC. To the extent the information in this prospectus supplement is inconsistent with information in the prospectus, you should rely on this prospectus supplement.

#### Notice to Prospective Investors in the European Economic Area
This prospectus supplement, the accompanying prospectus and any related free writing prospectus is not a prospectus for the purposes of Regulation (EU) 2017/1129 (the "Prospectus Regulation"). This prospectus supplement, the accompanying prospectus and any related free writing prospectus have been prepared on the basis that any offer of notes in any Member State of the European Economic Area (the "EEA") will only be made to a legal entity that is a qualified investor under the Prospectus Regulation ("EEA Qualified Investors"). Accordingly, any person making or intending to make an offer in that Member State of notes that are the subject of the offering contemplated in this prospectus supplement, the accompanying prospectus and any related free writing prospectus may only do so with respect to EEA Qualified Investors. Neither Exelon nor the underwriters have authorized, nor do they authorize, the making of any offer of notes other than to EEA Qualified Investors.

**PROHIBITION OF SALES TO EEA RETAIL INVESTORS** — The notes are not intended to be offered, sold or otherwise made available to and should not be offered, sold or otherwise made available to any retail investor in the EEA. For these purposes, a retail investor means a person who is one (or more) of: (i) a retail client as defined in point (11) of Article 4(1) of Directive 2014/65/EU, as amended ("MiFID II"); or (ii) a customer within the meaning of Directive (EU) 2016/97, as amended (the "Insurance Distribution Directive"), where that customer would not qualify as a professional client as defined in point (10) of Article 4(1) of MiFID II; or (iii) not a qualified investor as defined in the Prospectus Regulation. Consequently, no key information document required by Regulation (EU) No 1286/2014, as amended (the "PRIIPs Regulation") for offering or selling the notes or otherwise making them available to retail investors in the EEA has been prepared and therefore offering or selling the notes or otherwise making them available to any retail investor in the EEA may be unlawful under the PRIIPs Regulation.

#### Notice to Prospective Investors in the United Kingdom
This prospectus supplement, the accompanying prospectus and any related free writing prospectus is not a prospectus for the purposes of Regulation (EU) 2017/1129 as it forms part of domestic law in the United Kingdom by virtue of the European Union (Withdrawal) Act 2018, as amended by the European Union (Withdrawal Agreement) Act 2020 (the "EUWA") (the "UK Prospectus Regulation"). This prospectus supplement, the accompanying prospectus and any related free writing prospectus have been prepared on the basis that any offer of notes in the United Kingdom will only be made to a legal entity that is a qualified investor under the UK Prospectus Regulation ("UK Qualified Investors"). Accordingly, any person making or intending to make an offer in the United Kingdom of notes that are the subject of the offering contemplated in this prospectus supplement, the accompanying prospectus and any related free writing prospectus may only do so with respect to UK Qualified Investors. Neither Exelon nor the underwriters have authorized, nor do they authorize, the making of any offer of notes other than to UK Qualified Investors.

**PROHIBITION OF SALES TO UNITED KINGDOM RETAIL INVESTORS** — The notes are not intended to be offered, sold or otherwise made available to and should not be offered, sold or otherwise made available to any retail investor in the United Kingdom. For these purposes, a retail investor means a person who is one (or more) of: (i) a retail client, as defined in point (8) of Article 2 of Regulation (EU) No 2017/565 as it forms part of domestic law by virtue of the EUWA; or (ii) a customer within the meaning of the provisions of the United Kingdom's Financial Services and Markets Act 2000, as amended (the "FSMA") and any rules or regulations made under the FSMA to implement the Insurance Distribution Directive, where that customer would not qualify as a professional client, as defined in point (8) of Article 2(1) of Regulation (EU) No 600/2014 as it forms part of domestic law by virtue of the EUWA; or (iii) not a qualified investor as defined in Article 2 of the UK Prospectus Regulation. Consequently no key information document required by Regulation (EU) No 1286/2014 as it forms part of domestic law by virtue of the

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EUWA (the "UK PRIIPs Regulation") for offering or selling the notes or otherwise making them available to retail investors in the United Kingdom has been prepared and therefore offering or selling the notes or otherwise making them available to any retail investor in the United Kingdom may be unlawful under the UK PRIIPs Regulation.

The communication of this prospectus supplement, the accompanying prospectus, any related free writing prospectus and any other document or materials relating to the issue of the notes offered hereby is not being made, and such documents and/or materials have not been approved, by an authorized person for the purposes of section 21 of the FSMA. Accordingly, such documents and/or materials are not being distributed to, and must not be passed on to, the general public in the United Kingdom. This document and such other documents and/or materials are for distribution only to persons who (i) have professional experience in matters relating to investments and who fall within the definition of investment professionals (as defined in Article 19(5) of the Financial Services and Markets Act 2000 (Financial Promotion) Order 2005, as amended (the "Financial Promotion Order")), (ii) fall within Article 49(2)(a) to (d) of the Financial Promotion Order, (iii) are outside the United Kingdom or (iv) are any other persons to whom it may otherwise lawfully be made under the Financial Promotion Order (all such persons together being referred to as "relevant persons"). This document is directed only at relevant persons and must not be acted on or relied on by persons who are not relevant persons. Any investment or investment activity to which this prospectus supplement, the accompanying prospectus, any related free writing prospectus and any other document or materials relates will be engaged in only with, relevant persons. Any person in the United Kingdom that is not a relevant person should not act or rely on this prospectus supplement, the accompanying prospectus or any related free writing prospectus or any of their contents.

The accompanying prospectus also includes information about our subsidiaries, Commonwealth Edison Company (ComEd), PECO Energy Company (PECO), Baltimore Gas and Electric Company (BGE), Pepco Holdings LLC (PHI), Potomac Electric Power Company (Pepco), Delmarva Power & Light Company (DPL), Atlantic City Electric Company (ACE) and their securities. Exelon, ComEd, PECO, BGE, PHI, Pepco, DPL and ACE file combined reports under the Securities Exchange Act of 1934, as amended (the "Exchange Act"). Information contained in the combined reports relating to each registrant is filed separately by such registrant on its own behalf and only the information related to Exelon is incorporated by reference in this prospectus supplement and the accompanying prospectus. Exelon does not make any representations as to information relating to any other registrant or securities issued by any other registrant and you should not rely on any information relating to any registrant other than Exelon in determining whether to invest in the notes offered hereby.

When we refer to "Exelon," "the Company," "we," "us" or "our" in this prospectus supplement, we mean Exelon and, unless the context otherwise indicates, does not include any of our subsidiaries or affiliates.

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#### FORWARD LOOKING STATEMENTS
This prospectus supplement, the accompanying prospectus and the documents incorporated or deemed incorporated by reference as described under the heading "Where You Can Find More Information" contain forward-looking statements that are not based entirely on historical facts and are subject to risks and uncertainties. Words such as "believes," "anticipates," "expects," "intends," "plans," "predicts," "estimates" and similar expressions are intended to identify forward-looking statements but are not the only means to identify those statements. These forward-looking statements are based on assumptions, expectations and assessments made by our management in light of their experience and their perception of historical trends, current conditions, expected future developments and other factors they believe to be appropriate. Any forward-looking statements are not guarantees of our future performance and are subject to risks and uncertainties.

This prospectus supplement and the accompanying prospectus contain certain forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, which are subject to risks and uncertainties. The factors that could cause actual results to differ materially from the forward-looking statements include: (a) any risk factors discussed in this prospectus supplement or the accompanying prospectus; (b) those factors discussed in the following sections of Exelon's Annual Report on Form 10-K for the year ended December 31, 2022, which are incorporated herein by reference: (1) ITEM 1A. Risk Factors, (2) ITEM 7. Management's Discussion and Analysis of Financial Condition and Results of Operations and (3) ITEM 8. Financial Statements and Supplementary Data: Note 18; and (c) other factors discussed herein and in other filings with the SEC by Exelon, as applicable.

You are cautioned not to place undue reliance on these forward-looking statements, which apply only as of the date on the front of this prospectus supplement or, as the case may be, as of the date on which we make any subsequent forward-looking statement that is deemed incorporated by reference. We do not undertake any obligation to update or revise any forward-looking statement to reflect events or circumstances after the date as of which any such forward-looking statement is made.

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#### SUMMARY
 *The following summary is provided solely for your convenience. It is not intended to be complete and may not contain all of the information that you should consider before investing in the notes. You should read carefully this entire prospectus supplement, the accompanying prospectus and all the information included or incorporated by reference herein or therein.* 

#### Our Company
Exelon, incorporated in Pennsylvania in February 1999, is a utility services holding company engaged in energy distribution and transmission businesses through ComEd, PECO, BGE, Pepco, DPL and ACE (collectively, the "Utility Registrants"). Exelon's principal executive offices are located at 10 South Dearborn Street, Chicago, Illinois 60603, and its telephone number is 800-483-3220.

ComEd's energy delivery business consists of the purchase and regulated retail sale of electricity and the provision of electricity transmission and distribution services to retail customers in northern Illinois, including the City of Chicago.

PECO's energy delivery business consists of the purchase and regulated retail sale of electricity and the provision of electricity transmission and distribution services to retail customers in southeastern Pennsylvania, including the City of Philadelphia, as well as the purchase and regulated retail sale of natural gas and the provision of natural gas distribution services to retail customers in the Pennsylvania counties surrounding the City of Philadelphia.

BGE's energy delivery business consists of the purchase and regulated retail sale of electricity and natural gas and the transmission and distribution of electricity and distribution of natural gas to retail customers in central Maryland, including the City of Baltimore.

Pepco's energy delivery business consists of the purchase and regulated retail sale of electricity and the transmission and distribution of electricity to retail customers in the District of Columbia and major portions of Prince George's County and Montgomery County in Maryland.

DPL's energy delivery business consists of the purchase and regulated retail sale of electricity and the transmission and distribution of electricity to retail customers in portions of Delaware and Maryland, and the purchase and regulated retail sale of natural gas and distribution of natural gas to retail customers in portions of New Castle County in Delaware.

ACE's energy delivery business consists of the purchase and regulated retail sale of electricity and the transmission and distribution of electricity to retail customers in portions of southern New Jersey.

#### The Separation
On February 21, 2021, Exelon's Board of Directors approved a plan to separate ("the separation") the Utility Registrants and Constellation Energy Generation, LLC, a Pennsylvania limited liability company ("Generation"). Exelon completed the separation on February 1, 2022, creating two publicly traded companies, Exelon and Constellation Energy Corporation. Constellation Energy Corporation was newly formed and incorporated in Pennsylvania on June 15, 2021 for the purpose of the separation and holds Generation.

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#### SUMMARY FINANCIAL INFORMATION
We have provided the following summary financial information for your reference. We have derived the summary information presented here as of and for the years ended December 31, 2022, 2021 and 2020, as applicable, from our audited consolidated financial statements, incorporated herein by reference. You should read this summary information together with our audited consolidated financial statements, each incorporated herein by reference. See "Where You Can Find More Information" in this prospectus supplement.

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| | | | |
|:---|:---|:---|:---|
| | **For the Year Ended December 31,**  | **For the Year Ended December 31,**  | **For the Year Ended December 31,**  |
| | **2022**  | **2021**  | **2020**  |
|  | **($ in millions)**  | **($ in millions)**  | **($ in millions)**  |
| **Statement of Operations Data** |  |  |  |
| &nbsp;&nbsp;&nbsp; Operating revenues  | $19078 | $17938 | $16663 |
| &nbsp;&nbsp;&nbsp; Operating income  | 3315 | 2682 | 2191 |
| &nbsp;&nbsp;&nbsp; Net income from continuing operations after income taxes  | 2054 | 1616 | 1099 |
| &nbsp;&nbsp;&nbsp; Net income from discontinued operations after income taxes  | 117 | 213 | 855 |
| &nbsp;&nbsp;&nbsp; Net income  | 2171 | 1829 | 1954 |
| **Cash Flow Data** |  |  |  |
| &nbsp;&nbsp;&nbsp; Net cash flows provided by operating activities  | 4870 | 3012 | 4235 |
| &nbsp;&nbsp;&nbsp; Net cash flows used in investing activities  | (6990) | (3317) | (4336) |
| &nbsp;&nbsp;&nbsp; Net cash flows provided by financing activities  | 1591 | 758 | 145 |

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| | | |
|:---|:---|:---|
| | **For the Year Ended December 31,**  | **For the Year Ended December 31,**  |
| | **2022**  | **2021**  |
|  | **($ in millions)**  | **($ in millions)**  |
| **Balance Sheet Data** |  |  |
| &nbsp;&nbsp;&nbsp; Property, plant and equipment, net  | $69076 | $64558 |
| &nbsp;&nbsp;&nbsp; Noncurrent regulatory assets  | 8037 | 8224 |
| &nbsp;&nbsp;&nbsp; Goodwill  | 6630 | 6630 |
| &nbsp;&nbsp;&nbsp; Assets held for sale  |  | 13 |
| &nbsp;&nbsp;&nbsp; Current assets of discontinued operations  |  | 7835 |
| &nbsp;&nbsp;&nbsp; Total assets  | 95349 | 133013 |
| &nbsp;&nbsp;&nbsp; Long-term debt, including long-term debt to financing trusts and long-term <br> debt due within one year  | 37464 | 33292 |
| &nbsp;&nbsp;&nbsp; Noncurrent regulatory liabilities  | 9112 | 9628 |
| &nbsp;&nbsp;&nbsp; Liabilities held for sale  |  | 3 |
| &nbsp;&nbsp;&nbsp; Current liabilities of discontinued operations  |  | 7940 |
| &nbsp;&nbsp;&nbsp; Total shareholders' equity  | 24744 | 34393 |
| &nbsp;&nbsp;&nbsp; Total liabilities and shareholders' equity  | 95349 | 133013 |

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See also Note 2 — Discontinued Operations of the Combined Notes to Consolidated Financial Statements contained in Exelon's Annual Report on Form 10-K for the year ended December 31, 2022 for additional information on how the separation affects the summary financial information set forth herein.

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#### THE OFFERING
 *The following summary contains basic information about the notes and this offering. It does not contain all of the information that may be important to you. For a more complete understanding of this offering, we encourage you to read this entire prospectus supplement and the accompanying prospectus, including "Description of the Notes."* 

Issuer

Exelon Corporation

Securities Offered

$ aggregate principal amount of % notes due 20 ;

$ aggregate principal amount of % notes due 20 ; and

$ aggregate principal amount of % notes due 20

Maturity Date

The 20 notes will mature on March 15, 20 ;

The 20 notes will mature on March 15, 20 ; and

The 20 notes will mature on March 15, 20

Interest Rate

% per annum for the 20 notes;

% per annum for the 20 notes; and

% per annum for the 20 notes

Interest Payment Dates

Interest on the notes will be paid semi-annually on March 15 and September 15 of each year, beginning on September 15, 2023, and on the maturity date for each series of notes.

Optional Redemption

At any time prior to , 20 , in the case of the 20 notes, , 20 , in the case of the 20 notes, or , 20 , in the case of the 20 notes (in each case with respect to the applicable series of notes, the Par Call Date) we may redeem the notes at our option, in whole or in part, at any time and from time to time, at a redemption price (expressed as a percentage of principal amount and rounded to three decimal places) equal to the greater of:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • (a) the sum of the present values of the remaining scheduled payments of principal and interest thereon discounted to the redemption date (assuming the notes matured on the applicable Par Call Date) on a semi-annual basis (assuming a 360-day year consisting of twelve 30-day months) at the Treasury Rate plus (i) basis points, in the case of the 20 notes, (ii) basis points, in the case of the 20 notes, and (iii) basis points, in the case of the 20 notes, in each case, less (b) interest accrued to the date of redemption; and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • 100% of the principal amount of the notes then outstanding to be redeemed,

plus, in each case, accrued and unpaid interest thereon to but excluding the redemption date.

On or after the applicable Par Call Date, we may redeem the notes, in whole or in part, at any time and from time to time, at a redemption price equal to 100% of the principal amount of the notes being

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redeemed plus accrued and unpaid interest thereon to but excluding the redemption date. See "Description of the Notes — Optional Redemption."

Ranking

The notes will be our direct unsecured general obligations and will rank equally with all of our existing and future unsecured and unsubordinated debt, will be senior in right of payment to all of our existing and future subordinated debt and will be junior to any of our future secured debt to the extent of the value of the collateral securing such secured debt. Because we are a holding company with no material assets other than our ownership interests in our subsidiaries and all of our operations are conducted by our subsidiaries, our debt is effectively subordinated to all existing and future debt, trade creditors, and other liabilities of our subsidiaries. Our rights, and hence the rights of our creditors, to participate in any distribution of assets of any subsidiary upon its liquidation or reorganization or otherwise would be subject to the prior claims of that subsidiary's creditors, except to the extent that our claims as a creditor of such subsidiary may be recognized. As of December 31, 2022, our subsidiaries had outstanding approximately $28 billion of long-term debt, including long-term debt to financing trusts and the portion of long-term debt due within one year. The notes will not be obligations of or guaranteed by any of our subsidiaries. The Indenture (as defined below) does not limit our ability to issue debt senior to the notes or the amount of debt we or our subsidiaries may issue.

Denominations

The notes will be issued in minimum denominations of $2,000 and integral multiples of $1,000 in excess thereof.

Additional Notes

Subject to the limitations described in this prospectus supplement and the accompanying prospectus, we may issue additional notes under the Indenture with the same priority as the notes offered hereby, including notes having the same series designation and terms (except for the public offering prices and the issue date) as the notes offered hereby, without the approval of the holders of outstanding notes under the Indenture, including the holders of the outstanding notes offered hereby.

No Listing

We do not intend to list the notes on any securities exchange or automated dealer quotation system. The notes will be new securities for which there currently is no public market. See "Risk Factors — There may be no public market for the notes."

Use of Proceeds

We estimate that the net proceeds from the sale of the notes in this offering will be approximately $, after deducting the underwriting discounts and commissions but before deducting other offering expenses. A portion of the net proceeds from the sale of the notes, together with available cash balances, will be used to repay $850,000,000 of Exelon's outstanding term loans maturing in July 2023 and bearing interest at the Secured Overnight Financing Rate (SOFR) plus 0.65% and $588,000,000 of currently outstanding commercial paper borrowings having an approximate weighted average interest rate of 4.835% per annum as of February 13, 2023. The remainder of the net proceeds will be used for general corporate purposes. See "Use of Proceeds."

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Risk Factors

You should consider carefully all the information set forth and incorporated by reference in this prospectus supplement and the accompanying prospectus and, in particular, you should evaluate the specific factors set forth under the heading "Risk Factors" beginning on page S-9 of this prospectus supplement, as well as the other information contained or incorporated herein by reference, before investing in the notes offered hereby.

Conflicts of Interest

A portion of the net proceeds of this offering will be paid to an affiliate of SMBC Nikko Securities America, Inc., an underwriter in this offering, and to an affiliate of PNC Capital Markets LLC, an underwriter in this offering, in connection with the repayment of $850,000,000 of Exelon's outstanding term loans maturing in July 2023. Because these payments represent at least 5% of the net offering proceeds, SMBC Nikko Securities America, Inc. and PNC Capital Markets LLC are deemed to have a "conflict of interest" under FINRA Rule 5121. The appointment of a "qualified independent underwriter" is not required in connection with this offering as the securities offered are investment grade rated in accordance with Rule 5121. In accordance with Rule 5121, SMBC Nikko Securities America, Inc. and PNC Capital Markets LLC will not confirm any sales to any account over which either exercises discretionary authority without the specific written approval of the transaction from the account holder. See "Use of Proceeds" and "Underwriting (Conflicts of Interest)."

Trustee

The Bank of New York Mellon Trust Company, N.A.

Governing Law

The Indenture and the notes will be governed by the laws of the State of New York.

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#### RISK FACTORS
 *Investing in the notes involves risks. You should carefully consider the following discussion and the risks described under "Risk Factors" in [our Annual Report on Form 10-K for the year ended December 31, 2022](https://www.sec.gov/ix?doc=/Archives/edgar/data/8192/000110935723000018/exc-20221231.htm), incorporated by reference in this prospectus supplement and the accompanying prospectus, the factors listed under "Forward Looking Statements" in this prospectus supplement and the other information contained or incorporated by reference in this prospectus supplement and the accompanying prospectus before making a decision to invest in the notes. See "Where You Can Find More Information."* 

#### General market conditions may adversely affect the market prices of the notes and there may be no public market for the notes.
We can give no assurances concerning the future market prices of the notes, the liquidity of any markets that may develop for the notes offered by this prospectus supplement, the ability of any investor to sell any of the notes or the price at which investors would be able to sell them. The condition of the financial markets and prevailing interest rates have fluctuated in the past and are likely to fluctuate in the future, which could have an adverse effect on the market prices of the notes. If markets for the notes do not develop, investors may be unable to resell the notes for an extended period of time, if at all. If markets for the notes do develop, they may not continue or it may not be sufficiently liquid to allow holders to resell any of the notes. Consequently, investors may not be able to liquidate their investment readily, and lenders may not readily accept the notes as collateral for loans.

#### The Indenture does not restrict the amount of additional debt that we may incur.
The notes and Indenture pursuant to which the notes will be issued do not place any limitation on the amount of indebtedness that we or our subsidiaries may incur. Our incurrence of additional debt may have important consequences for you as a holder of the notes, including making it more difficult for us to satisfy our obligations with respect to the notes, a loss in the trading value of your notes and a risk that one or more of the credit ratings of the notes are lowered or withdrawn.

#### Our debt, including the notes, is effectively subordinated to the debt of our subsidiaries.
Because we are a holding company with no material assets other than our ownership interests in our subsidiaries and all of our operations are conducted by our subsidiaries, our debt is effectively subordinated to all existing and future debt, trade creditors, and other liabilities of our subsidiaries. Our rights, and hence the rights of our creditors, to participate in any distribution of assets of any subsidiary upon its liquidation or reorganization or otherwise would be subject to the prior claims of that subsidiary's creditors, except to the extent that our claims as a creditor of such subsidiary may be recognized. As of December 31, 2022, our subsidiaries had outstanding approximately $28 billion of long-term debt, including long-term debt to financing trusts and the portion of long-term debt due within one year. The Indenture does not restrict our or our subsidiaries' ability to incur additional indebtedness.

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#### USE OF PROCEEDS
We estimate that the net proceeds from the sale of the notes in this offering will be approximately $, after deducting the underwriting discounts and commissions but before deducting other offering expenses. A portion of the net proceeds from the sale of the notes, together with available cash balances, will be used to repay $850,000,000 of Exelon's outstanding term loans maturing in July 2023 and bearing interest at the Secured Overnight Financing Rate (SOFR) plus 0.65% and $588,000,000 of currently outstanding commercial paper borrowings issued at the Exelon Corporation level having an approximate weighted average interest rate of 4.835% per annum as of February 13, 2023. The remainder of the net proceeds will be used for general corporate purposes. To the extent we do not use the net proceeds immediately, we may temporarily invest them in short-term, interest bearing obligations.

A portion of the net proceeds of this offering will be paid to an affiliate of SMBC Nikko Securities America, Inc., an underwriter in this offering, and to an affiliate of PNC Capital Markets LLC, an underwriter in this offering, in connection with the repayment of the $850,000,000 of Exelon's outstanding term loans maturing in July 2023. Because these payments represent at least 5% of the net offering proceeds, SMBC Nikko Securities America, Inc. and PNC Capital Markets LLC are deemed to have a "conflict of interest" under FINRA Rule 5121. The appointment of a "qualified independent underwriter" is not required in connection with this offering as the securities offered are investment grade rated in accordance with Rule 5121. In accordance with Rule 5121, SMBC Nikko Securities America, Inc. and PNC Capital Markets LLC will not confirm any sales to any account over which either exercises discretionary authority without the specific written approval of the transaction from the account holder. See "Underwriting (Conflicts of Interest)."

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#### CAPITALIZATION
The following table shows our consolidated capitalization as of December 31, 2022 and as adjusted to reflect the issuance of the notes offered by this prospectus supplement and the application of the net proceeds thereof. See "Use of Proceeds." This table is qualified in its entirety by, and should be considered in conjunction with, the more detailed information incorporated by reference or provided in this prospectus supplement or in the accompanying prospectus.

---

| | | |
|:---|:---|:---|
| | **As of December 31, 2022**  | **As of December 31, 2022**  |
| | **Actual**  | **As Adjusted**  |
|  | **($ in millions) <br> (unaudited)**  | **($ in millions) <br> (unaudited)**  |
| Short-term borrowings<sup>(a)</sup>  | $2586 | $|
| Long-term debt<sup>(b)</sup>:  | 37464 |  |
| &nbsp;&nbsp;&nbsp; 20 notes offered hereby  |  |  |
| &nbsp;&nbsp;&nbsp; 20 notes offered hereby  |  |  |
| &nbsp;&nbsp;&nbsp; 20 notes offered hereby  |  |  |
| Total shareholders' equity  | 24744 |  |
| Total capitalization  | $64794 | $|

---

(a) As described under "Use of Proceeds" above, we had approximately $588 million of outstanding commercial paper issued at the Exelon Corporation level as of February 13, 2023, which will be retired using a portion of the proceeds from the notes.

(b) Includes long-term debt to financing trusts and approximately $1.8 billion of long-term debt due within one year, of which $850 million is in the form of term loans that will be retired using a portion of the proceeds from the notes as described under "Use of Proceeds."

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#### DESCRIPTION OF THE NOTES
The following description of the notes is only a summary and is not intended to be comprehensive. In the event that information in this prospectus supplement is inconsistent with information in the accompanying prospectus, you should rely on this prospectus supplement.

#### General
We will issue $ of the % notes due 20 , $ of the % notes due 20 and, $ of the % notes due 20 under an indenture, which is a contract between us and the trustee, The Bank of New York Mellon Trust Company, N.A. (the "Trustee"), dated June 11, 2015 as will be supplemented by the supplemental indenture dated as of February 1, 2023 and as it may be further supplemented from time to time, which is referred to herein collectively as the "Indenture." Subject to the limitations described in this prospectus supplement and the accompanying prospectus, we may issue additional notes under the Indenture with the same priority as the notes offered hereby, including notes having the same series designation and terms (except for the public offering prices and the issue date) as the notes offered hereby, without the approval of the holders of outstanding notes under the Indenture, including the holders of any series the outstanding notes offered hereby.

The terms of the notes will not necessarily afford you protection in the event of particular transactions or upon the occurrence of particular events that may adversely affect you, including a reorganization, recapitalization, restructuring, merger or other similar transactions involving us or our subsidiaries, whether or not in connection with a change of control. As a result, we could enter into such transactions even though the transaction could adversely affect our capital structure or credit ratings or otherwise adversely affect the holders of the notes. The notes will not contain any provisions that will require us to redeem, or permit the holders of the notes to cause a redemption or purchase of, the notes upon the occurrence of any particular event. However, we may redeem some or all of the notes at any time or from time to time prior to maturity, at our option, as described in this prospectus supplement under "— Optional Redemption" below.

#### Interest Rate and Maturity
The 20 notes will pay interest at the fixed rate of % per annum, the 20 notes will pay interest at the fixed rate of % per annum and the 20 notes will pay interest at the fixed rate of % per annum. Interest on the notes will be payable semi-annually on March 15 and September 15 of each year, beginning on September 15, 2023. The 20 notes will mature on March 15, 20 , the 20 notes will mature on March 15, 20 and the 20 notes will mature on March 15, 20 .

Interest on the notes will accrue from and include the date that the notes are issued to and excluding the date of maturity or redemption. Interest will be computed on the basis of a 360-day year of twelve 30-day months. On each interest payment date, we will pay interest on each note to the person in whose name the note is registered at the close of business on the record date for such interest. The record date for each interest payment date in respect of the notes will be the close of business on the Business Day immediately preceding the applicable interest payment date. If any interest payment date falls on a day that is not a Business Day, payment will be made on the next Business Day and no additional interest or other payment will be paid in respect of such delay. "Business Day" means any day that is not a Saturday, a Sunday or a day on which commercial banking institutions in New York City are generally authorized or required by law or executive order to be closed.

#### Ranking
The notes will be our direct unsecured general obligations and will rank equally with all of our existing and future unsecured and unsubordinated debt, will be senior in right of payment to all of our existing and future subordinated debt and will be junior to any of our future secured debt to the extent of the value of the collateral securing such secured debt. Because we are a holding company with no material assets other than our ownership interests in our subsidiaries and all of our operations are conducted by our subsidiaries, our debt is effectively subordinated to all existing and future debt, trade creditors, and other liabilities of our subsidiaries. Our rights, and hence the rights of our creditors, to participate in any distribution of assets

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of any subsidiary upon its liquidation or reorganization or otherwise would be subject to the prior claims of that subsidiary's creditors, except to the extent that our claims as a creditor of such subsidiary may be recognized. As of December 31, 2022, our subsidiaries had outstanding approximately $28 billion of long-term debt, including long-term debt to financing trusts and the portion of long-term debt due within one year. The Indenture does not restrict our or our subsidiaries' ability to incur additional indebtedness. In addition, the notes will not be obligations of or guaranteed by any of our subsidiaries. The Indenture does not limit our ability to issue secured debt senior to the notes or the amount of debt we or our subsidiaries may issue, whether secured or unsecured.

Please see "Capitalization" in this prospectus supplement for information with respect to the long-term debt and short-term borrowings of us and our subsidiaries as of December 31, 2022.

#### Form and Denomination
The notes will be issued in registered form in minimum denominations of $2,000 and integral multiples of $1,000 in excess thereof.

The notes will initially be issued in "book-entry only form," represented by a permanent global debt security registered in the name of DTC, including Clearstream and/or Euroclear, or its nominee. However, we reserve the right to issue notes in certificated form registered in the name of the noteholders. For so long as the notes are registered in the name of DTC or its nominee, we will pay the principal, premium, if any, and interest due on the notes to DTC for payment to its participants for subsequent disbursement to the beneficial owners. For further information on DTC and its practices, see "Book-Entry System" below.

#### Optional Redemption
At any time prior to , 20 , in the case of the 20 notes, , 20 , in the case of the 20 notes, or on , 20 , in the case of the 20 notes (in each case with respect to the applicable series of notes, the Par Call Date) we may redeem the notes at our option, in whole or in part, at any time and from time to time, at a redemption price (expressed as a percentage of principal amount and rounded to three decimal places) equal to the greater of:

• &nbsp;&nbsp;&nbsp;&nbsp; (a) the sum of the present values of the remaining scheduled payments of principal and interest thereon discounted to the redemption date (assuming the notes matured on the applicable Par Call Date) on a semi-annual basis (assuming a 360-day year consisting of twelve 30-day months) at the Treasury Rate plus (i) basis points, in the case of the 20 notes, (ii) basis points, in the case of the 20 notes and (iii) basis points, in the case of the 20 notes, in each case, less (b) interest accrued to the date of redemption; and,

• 100% of the principal amount of the notes then outstanding to be redeemed,

plus, in each case, accrued and unpaid interest thereon to but excluding the redemption date.

On or after the applicable Par Call Date, we may redeem the notes, in whole or in part, at any time and from time to time, at a redemption price equal to 100% of the principal amount of the notes being redeemed plus accrued and unpaid interest thereon to but excluding the redemption date.

Any optional redemption may be conditioned upon the consummation of one or more other transactions, including any debt or equity issuance by us or any of our parent companies or subsidiaries. The Trustee shall not have responsibility for calculating any redemption price. Redemption of the notes of one series may be made without the redemption the notes of any other series.

"Treasury Rate" means, with respect to any redemption date, the yield determined by us in accordance with the following two paragraphs.

The Treasury Rate shall be determined by us after 4:15 p.m., New York City time (or after such time as yields on U.S. government securities are posted daily by the Board of Governors of the Federal Reserve System), on the third business day preceding the redemption date based upon the yield or yields for the most recent day that appear after such time on such day in the most recent statistical release published by the Board of Governors of the Federal Reserve System designated as "Selected Interest Rates (Daily) — H.15"

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(or any successor designation or publication) ("H.15") under the caption "U.S. government securities — Treasury constant maturities — Nominal" (or any successor caption or heading) ("H.15 TCM"). In determining the Treasury Rate, we shall select, as applicable: (1) the yield for the Treasury constant maturity on H.15 exactly equal to the period from the redemption date to the Par Call Date (the "Remaining Life"); or (2) if there is no such Treasury constant maturity on H.15 exactly equal to the Remaining Life, the two yields — one yield corresponding to the Treasury constant maturity on H.15 immediately shorter than and one yield corresponding to the Treasury constant maturity on H.15 immediately longer than the Remaining Life — and shall interpolate to the Par Call Date on a straight-line basis (using the actual number of days) using such yields and rounding the result to three decimal places; or (3) if there is no such Treasury constant maturity on H.15 shorter than or longer than the Remaining Life, the yield for the single Treasury constant maturity on H.15 closest to the Remaining Life. For purposes of this paragraph, the applicable Treasury constant maturity or maturities on H.15 shall be deemed to have a maturity date equal to the relevant number of months or years, as applicable, of such Treasury constant maturity from the redemption date.

If on the third business day preceding the redemption date H.15 TCM is no longer published, we shall calculate the Treasury Rate based on the rate per annum equal to the semi-annual equivalent yield to maturity at 11:00 a.m., New York City time, on the second business day preceding such redemption date of the United States Treasury security maturing on, or with a maturity that is closest to, the Par Call Date, as applicable. If there is no United States Treasury security maturing on the Par Call Date but there are two or more United States Treasury securities with a maturity date equally distant from the Par Call Date, one with a maturity date preceding the Par Call Date and one with a maturity date following the Par Call Date, we shall select the United States Treasury security with a maturity date preceding the Par Call Date. If there are two or more United States Treasury securities maturing on the Par Call Date or two or more United States Treasury securities meeting the criteria of the preceding sentence, we shall select from among these two or more United States Treasury securities the United States Treasury security that is trading closest to par based upon the average of the bid and asked prices for such United States Treasury securities at 11:00 a.m., New York City time. In determining the Treasury Rate in accordance with the terms of this paragraph, the semi-annual yield to maturity of the applicable United States Treasury security shall be based upon the average of the bid and asked prices (expressed as a percentage of principal amount) at 11:00 a.m., New York City time, of such United States Treasury security, and rounded to three decimal places.

Our actions and determinations in determining the redemption price shall be conclusive and binding for all purposes, absent manifest error.

Notice of any redemption will be mailed or electronically delivered (or otherwise transmitted in accordance with the depositary's procedures) at least 10 days but not more than 60 days before the redemption date to each holder of notes to be redeemed.

In the case of a partial redemption, notes in definitive form will be selected for redemption by lot by the Trustee. No notes of a principal amount of $2,000 or less will be redeemed in part. If any note in definitive form is to be redeemed in part only, the notice of redemption that relates to such note will state the portion of the principal amount of the note to be redeemed. A new note in definitive form in a principal amount equal to the unredeemed portion of the original note in definitive form will be issued in the name of the holder of such note upon surrender for cancellation of the original definitive note. For so long as the notes are in global form and held by DTC (or another depositary), the redemption of the notes, including the selection of notes in the case of a partial redemption, shall be done in accordance with the policies and procedures of the depositary. Unless we default in payment of the redemption price, on and after the redemption date interest will cease to accrue on the notes or portions thereof called for redemption.

#### Events of Default
An "Event of Default" with respect to a series of debt securities issued under the Indenture means any of the following:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • we fail to pay the principal of (or premium, if any, on) any debt security of that series when due and payable;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • we fail to pay any interest on any debt security of that series for 30 days after such is due;

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&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • we fail to observe or perform any other covenants or agreements set forth in the debt securities of that series, or in the Indenture in regard to such debt securities, continuously for 90 days after notice (which must be sent either by the Trustee or holders of at least 33% of the principal amount of the affected series);

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • our failure to pay principal at maturity or acceleration following a default in an aggregate amount of $100 million or more with respect to any Indebtedness (as defined below) of Exelon Corporation (not including Indebtedness of our subsidiaries), or the acceleration of any of our Indebtedness aggregating $100 million or more which default is not cured, waived or postponed pursuant to an agreement with the holders of the Indebtedness within 30 days after written notice as provided in the Indenture, or the acceleration is not rescinded or annulled within 30 days after written notice as provided in the Indenture; or

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • we file for bankruptcy or certain other events of bankruptcy, insolvency or reorganization occur.

As used in the immediately preceding paragraph, "Indebtedness" means all obligations for borrowed money.

An Event of Default for a particular series of debt securities does not necessarily mean that an Event of Default has occurred for any other series of debt securities issued under the Indenture. If an Event of Default has occurred and has not been cured, the Trustee or the holders of not less than 33% of the principal amount of the debt securities of the affected series may declare the entire principal of the debt securities of such series due and payable immediately. Subject to certain conditions, if we deposit with the Trustee enough money to remedy the default and there is no default continuing, this acceleration of payment may be rescinded by the holders of at least a majority in aggregate principal amount of the debt securities of such series.

The Trustee must, within 90 days after a default occurs, notify the holders of the debt securities of the series of the default if we have not remedied it (default is defined to include the events specified above without the grace periods or notice). The Trustee may withhold notice to the holders of such debt securities of any default (except in the payment of principal or interest) if it in good faith considers such withholding in the interest of the holders. We are required to file an annual certificate with the Trustee, signed by an officer, stating any default by us under any provisions of the Indenture.

Prior to any declaration of acceleration of maturity, the holders holding a majority of the principal amount of the debt securities of the particular series affected, on behalf of the holders of all debt securities of that series, may waive any past default or Event of Default. We cannot, however, obtain a waiver of a payment default.

Other than the duty to act with the required standard of care during an event of default, the Trustee is not required to take any action under the Indenture at the request of any holders unless such holders offer the Trustee reasonable indemnity. Subject to the provisions for indemnification and certain other limitations, the holders of a majority in principal amount of the debt securities of any series may direct the time, method and place of conducting any proceedings for any remedy available to the Trustee with respect to such debt securities.

In order to bypass the Trustee and take steps to enforce your rights or protect your interests relating to the debt securities, the following must occur:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • you must give the Trustee written notice that an Event of Default has occurred and remains uncured;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the holders of 33% of the principal amount of all outstanding debt securities of the relevant series must make a written request that the Trustee take action because of the default, and must offer reasonable indemnity to the Trustee against the cost and other liabilities of taking that action; and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the Trustee must have not taken action for 60 days after receipt of the above notice and offer of indemnity.

However, you are entitled at any time to bring a lawsuit for the payment of money due on your debt security on or after its due date.

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"Street name" and other indirect holders should consult their banks or brokers for information on how to give notice or direction to, or make a request of, the Trustee and to make or cancel a declaration of acceleration.

#### Supplemental Indentures
There are three types of changes we can make to the Indenture and the debt securities issued thereunder, including the notes.

#### Changes Requiring Each Holder's Approval
The following changes require the approval of each holder of debt securities of the series affected then outstanding:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • extending the fixed maturity of any debt security;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • reducing the interest rate or extending the time of payment of interest;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • reducing any premium payable upon redemption;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • reducing the principal amount;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • reducing the amount of principal payable upon acceleration of the maturity of a discounted debt security following default;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • changing the currency of payment on a debt security; or

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • reducing the percentage of securityholders whose consent is required to modify or amend the Indenture.

#### Changes Not Requiring Holder Approval
Changes not requiring holder approval are limited to those changes specified in the Indenture, including those which are of an administrative nature or are changes that would not adversely affect holders of the debt securities.

#### Changes Requiring a Majority of all Holders to Approve
A vote in favor by securityholders owning a majority of the principal amount of the debt securities of a particular series of affected debt securities is required for any other matter listed in the Indenture.

#### Consolidation, Merger or Sale
We may not merge or consolidate with any person (as defined in the Indenture) or sell substantially all of our assets as an entirety unless:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • we are the continuing corporation or the successor person is organized under the laws of the United States or a state or is organized under the laws of a foreign jurisdiction and consents to the jurisdiction of the courts of the United States or a state and expressly assumes the payment of principal, and premium, if any, and interest on the debt securities and the performance and observance of all the covenants and conditions of the Indenture binding on us; and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • we, or the successor person, are not immediately after the merger, consolidation or sale in default in the performance of a covenant or condition in the Indenture binding on us.

#### Discharge, Defeasance and Covenant Defeasance
We may discharge certain obligations to holders of the notes of a series that have not already been delivered to the Trustee for cancellation and that either have become due and payable or will become due and payable within one year (or scheduled for redemption within one year) by irrevocably depositing with the Trustee, in trust, funds in U.S. dollars in an amount sufficient to pay the entire indebtedness including, but not limited to, the principal and premium, if any, and interest to the date of such deposit (if the debt securities

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have become due and payable) or to the maturity thereof or the redemption date of the debt securities of that series, as the case may be. We may direct the Trustee to invest such funds in U.S. Treasury securities with a maturity of one year or less or in a money market fund that invests solely in short-term U.S. Treasury securities.

The Indenture provides that we may elect either (1) to defease and be discharged from any and all obligations with respect to the notes of a series (except for, among other things, obligations to maintain an office or agency with respect to the debt securities and to hold moneys for payment in trust) ("legal defeasance") or (2) to be released from our obligations to comply with the restrictive covenants under the Indenture, and any omission to comply with such obligations will not constitute a default or an event of default with respect to the notes of a series and such related clause under "— Events of Default" will no longer be applied ("covenant defeasance"). Legal defeasance or covenant defeasance, as the case may be, will be conditioned upon, among other things, the irrevocable deposit by us with the Trustee, in trust, of an amount in U.S. dollars, or U.S. government obligations, or both, applicable to the debt securities of that series which through the scheduled payment of principal and interest in accordance with their terms will provide money in an amount sufficient to pay the principal or premium, if any, and interest on the notes on the scheduled due dates therefor.

If we effect covenant defeasance with respect to the notes of any series, the amount in U.S. dollars, or U.S. government obligations, or both, on deposit with the Trustee will be sufficient, in the opinion of a nationally recognized firm of independent accountants, to pay amounts due on the notes of that series at the time of the stated maturity but may not be sufficient to pay amounts due on the notes of that series at the time of the acceleration resulting from such event of default. However, we would remain liable to make payment of such amounts due at the time of acceleration.

We will be required to deliver to the Trustee an opinion of counsel that the deposit and related defeasance will not cause the holders and beneficial owners of the notes of that series to recognize income, gain or loss for federal income tax purposes. If we elect legal defeasance, that opinion of counsel must be based upon a ruling from the U.S. Internal Revenue Service or a change in law to that effect.

We may exercise our legal defeasance option notwithstanding our prior exercise of our covenant defeasance option.

#### Open Market Purchases
We may acquire the notes by means other than a redemption, whether by tender offer, open market purchases, negotiated transactions or otherwise, in accordance with applicable securities laws, so long as such acquisition does not otherwise violate the terms of the Indenture.

#### Governing Law
The Indenture and the notes will be governed by the laws of the State of New York.

#### Concerning the Trustee
We and our affiliates use or may use some of the banking services of the Trustee in the normal course of business.

#### Book-Entry System
We will issue the notes in the form of one or more global notes in fully registered form initially in the name of Cede & Co., as nominee of DTC, or such other name as may be requested by an authorized representative of DTC. The global notes will be deposited with DTC and may not be transferred except as a whole by DTC to a nominee of DTC or by a nominee of DTC to DTC or another nominee of DTC or by DTC or any nominee to a successor of DTC or a nominee of such successor.

DTC, the world's largest securities depository, is a limited-purpose trust company organized under the New York Banking Law, 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

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Uniform Commercial Code, and a "clearing agency" registered pursuant to the provisions of Section 17A of the Exchange Act. DTC holds and provides asset servicing for U.S. and non-U.S. equity, corporate and municipal debt issues, and money market instruments that DTC's participants (direct participants) deposit with DTC. DTC also facilitates the post-trade settlement among direct participants of sales and other securities transactions in deposited securities through electronic computerized book-entry transfers and pledges between direct participants' accounts. This eliminates the need for physical movement of securities certificates. Direct participants include both U.S. and non-U.S. securities brokers and dealers, banks, trust companies, clearing corporations, and certain other organizations. DTC is a wholly-owned subsidiary of The Depository Trust & Clearing Corporation (DTCC). DTCC is the holding company for DTC, National Securities Clearing Corporation and Fixed Income Clearing Corporation, all of which are registered clearing agencies. DTCC is owned by the users of its regulated subsidiaries. Access to the DTC system is also available to others such as both U.S. and non-U.S. securities brokers and dealers, banks, trust companies, and clearing corporations that clear through or maintain a custodial relationship with a direct participant, either directly or indirectly (indirect participants). The rules applicable to DTC and its direct and indirect participants are on file with the SEC. More information about DTC can be found at www.dtcc.com. We do not intend this internet address to be an active link or to otherwise incorporate the content of the website into this prospectus supplement.

Clearstream advises that it is incorporated under the laws of Luxembourg as a bank. Clearstream holds securities for its customers and facilitates the clearance and settlement of securities transactions between its customers through electronic book-entry transfers between their accounts. Clearstream provides to its customers among other things, services for safekeeping, administration, clearance and settlement of internationally traded securities and securities lending and borrowing. Clearstream interfaces with domestic securities markets in over 30 countries through established depository and custodial relationships. As a bank, Clearstream is subject to regulation by the Luxembourg Commission for the Supervision of the Financial Sector, also known as the *Commission de Surveillance du Secteur Financier*. Its customers are recognized financial institutions around the world, including underwriters, securities brokers and dealers, banks, trust companies, clearing corporations and certain other organizations. Its customers in the United States are limited to securities brokers and dealers and banks. Indirect access to Clearstream is also available to other institutions such as banks, brokers, dealers and trust companies that clear through or maintain a custodial relationship with the customer.

Euroclear advises that it was created in 1968 to hold securities for its participants and to clear and settle transactions between Euroclear participants through simultaneous electronic book-entry delivery against payment, thereby eliminating the need for physical movement of certificates and any risk from lack of simultaneous transfers of securities and cash. Euroclear provides various other services, including securities lending and borrowing and interfaces with domestic markets in several countries. Euroclear is operated by Euroclear Bank S.A./N.V.. Euroclear Clearance establishes policy for Euroclear on behalf of Euroclear participants. Euroclear participants include banks, including central banks, securities brokers and dealers and other professional financial intermediaries and may include the Initial purchasers. Indirect access to Euroclear is also available to other firms that clear through or maintain a custodial relationship with a Euroclear participant, either directly or indirectly. Securities clearance accounts and cash accounts with the Euroclear operator are governed by the terms and conditions governing use of Euroclear and the related operating procedures of Euroclear. These terms and conditions govern transfers of securities and cash within Euroclear, withdrawals of securities and cash from Euroclear, and receipts of payments with respect to securities in Euroclear. All securities in Euroclear are held on a fungible basis without attribution of specific certificates to specific securities clearance accounts. The Euroclear operator acts under the terms and conditions only on behalf of Euroclear participants and has no record of or relationship with persons holding through Euroclear participants.

Euroclear further advises that investors that acquire, hold and transfer interests in the notes by book-entry through accounts with the Euroclear operator or any other securities intermediary are subject to the laws and contractual provisions governing their relationship with their intermediary, as well as the laws and contractual provisions governing the relationship between such an intermediary and each other intermediary, if any, standing between themselves and the global securities.

Purchases of notes under the DTC system must be made by or through direct participants, which will receive a credit for the notes in DTC's records. The ownership interest of each actual purchaser of notes

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(beneficial owner) is in turn to be recorded on the direct and indirect participants' records. Beneficial owners of the notes will not receive written confirmation from DTC of their purchase, but beneficial owners are expected to receive written confirmations providing details of the transaction, as well as periodic statements of their holdings, from the direct or indirect participant through which the beneficial owner entered into the transaction. Transfers of ownership interests in the notes are to be accomplished by entries made on the books of direct and indirect participants acting on behalf of beneficial owners. Beneficial owners will not receive certificates representing their ownership interests in the notes, except in the event that use of the book-entry system for the notes is discontinued.

To facilitate subsequent transfers, all notes deposited by direct participants with DTC are registered in the name of DTC's partnership nominee, Cede & Co., or such other name as may be requested by an authorized representative of DTC. The deposit of notes with DTC and their registration in the name of Cede & Co. or such other nominee do not effect any change in beneficial ownership. DTC has no knowledge of the actual beneficial owners of the notes; DTC's records reflect only the identity of the direct participants to whose accounts such notes are credited, which may or may not be the beneficial owners. The direct and indirect participants will remain responsible for keeping account of their holdings on behalf of their customers.

Conveyance of notices and other communications by DTC to direct participants, by direct participants to indirect participants, and by direct participants and indirect participants to beneficial owners will be governed by arrangements among them, subject to any statutory or regulatory requirements as may be in effect from time to time. The laws of some jurisdictions may require that certain persons take physical delivery in definitive form of securities which they own. Consequently, those persons may be prohibited from purchasing beneficial interests in the global notes from any beneficial owner or otherwise.

Redemption notices shall be sent to DTC. If less than all of the notes within an issue are being redeemed, DTC's practice is to determine by lot the amount of the interest of each direct participant in such issue to be redeemed.

So long as DTC's nominee is the registered owner of the global notes, such nominee for all purposes will be considered the sole owner or holder of the notes for all purposes under the Indenture. Except as provided below, beneficial owners will not be entitled to have any of the notes registered in their names, will not receive or be entitled to receive physical delivery of the notes in definitive form and will not be considered the owners or holders thereof under the Indenture.

Neither DTC nor Cede & Co. (nor such other DTC nominee) will consent or vote with respect to the notes. Under its usual procedures, DTC mails an omnibus proxy to the issuer as soon as possible after the record date. The omnibus proxy assigns Cede & Co.'s consenting or voting rights to those direct participants to whose accounts the notes are credited on the record date (identified in a listing attached to the omnibus proxy).

All payments on the global notes will be made to Cede & Co., or such other nominee as may be requested by an authorized representative of DTC. DTC's practice is to credit direct participants' accounts upon DTC's receipt of funds and corresponding detail information from trustees or issuers on payment dates in accordance with their respective holdings shown on DTC's records. Payments by participants to beneficial owners will be governed by standing instructions and customary practices, as is the case with securities held for the accounts of customers in bearer form or registered in "street name," and will be the responsibility of such participant and not of DTC, the Trustee or us, subject to any statutory or regulatory requirements as may be in effect from time to time. Payment of principal and interest to Cede & Co. (or such other nominee as may be requested by an authorized representative of DTC) shall be the responsibility of the Trustee or us, disbursement of such payments to direct participants shall be the responsibility of DTC, and disbursement of such payments to the beneficial owners shall be the responsibility of direct and indirect participants.

DTC may discontinue providing its service as securities depositary with respect to the notes at any time by giving reasonable notice to us or the Trustee. In addition, we may decide to discontinue use of the system of book-entry transfers through DTC (or a successor securities depositary). In the event that a successor securities depositary is not obtained under the above circumstances, or, alternatively, if an event of default with respect to the notes has occurred and is outstanding, note certificates in fully registered form are required to be printed and delivered to beneficial owners of the global notes representing such notes.

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Secondary market trading between DTC participants will occur in the ordinary way in accordance with DTC's rules and will be settled in immediately available funds using DTC's same-day funds settlement system. Secondary market trading between Clearstream customers and/or Euroclear participants will occur in the ordinary way in accordance with the applicable rules and operating procedures of Clearstream and Euroclear and will be settled using the procedures applicable to conventional Eurobonds in immediately available funds.

Cross market transfers between persons holding directly or indirectly through DTC on the one hand, and directly or indirectly through Clearstream customers or Euroclear participants, on the other, will be effected in DTC in accordance with DTC's rules on behalf of the relevant European international clearing system by its U.S. depositary; however, such cross market transactions will require delivery of instructions to the relevant European international clearing system by the counterparty in such system in accordance with its rules and procedures and within its established deadlines, in European time. The relevant European international clearing system will, if the transaction meets its settlement requirements, deliver instructions to its U.S. depository to take action to effect final settlement on its behalf by delivering interests in the notes to or receiving interests in the notes from DTC, and making or receiving payment in accordance with normal procedures for same-day funds settlement applicable to DTC. Clearstream customers and Euroclear participants may not deliver instructions directly to their respective U.S. depositaries.

Because of time-zone differences, credits of interests in the notes received by Clearstream or Euroclear as a result of a transaction with a DTC participant will be made during subsequent securities settlement processing and dated the Business Day following the DTC settlement date. Such credits or any transactions involving interests in such notes settled during such processing will be reported to the relevant Clearstream customers or Euroclear participants on such Business Day. Cash received by Clearstream or Euroclear as a result of sales of interests in the notes by or through a Clearstream customer or a Euroclear participant to a DTC participant will be received with value on the DTC settlement date but will be available in the relevant Clearstream or Euroclear cash account only as of the Business Day following settlement in DTC.

The information in this section has been obtained from sources that we believe to be reliable, but we take no responsibility for its accuracy.

Neither we, the Trustee nor the underwriters will have any responsibility or obligation to direct participants, or the persons for whom they act as nominees, with respect to the accuracy of the records of DTC, its nominee or any direct participant with respect to any ownership interest in the notes, or payments to, or the providing of notice to direct participants or beneficial owners.

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#### MATERIAL UNITED STATES FEDERAL INCOME TAX CONSIDERATIONS
The following is a summary of the material United States federal income tax considerations relating to the purchase, ownership and disposition of the notes, but does not purport to be a complete analysis of all potential tax considerations. This summary is based on the United States Internal Revenue Code of 1986, as amended (the Code), the Treasury regulations promulgated thereunder, judicial authority, published administrative positions of the United States Internal Revenue Service (IRS) and other applicable authorities, all as in effect on the date of this document, and all of which are subject to change, possibly on a retroactive basis. We have not sought any ruling from the IRS with respect to the statements made and the conclusions reached in the following summary and there can be no assurance that the IRS will agree with our statements and conclusions or that a court would not sustain any challenge by the IRS in the event of litigation.

This summary deals only with beneficial owners of notes that acquire the notes for cash in this offering at their issue price (generally, the first price at which a substantial amount of the notes are sold for money to investors (excluding sales to bond houses, brokers or similar persons or organizations acting in the capacity of underwriters, placement agents or wholesalers)) and that will hold the notes as "capital assets" within the meaning of section 1221 of the Code (generally, property held for investment). This summary does not purport to deal with all aspects of United States federal income taxation that might be relevant to particular beneficial owners in light of their personal investment circumstances or status, nor does it address tax considerations applicable to beneficial owners that may be subject to special tax rules, such as banks and financial institutions, individual retirement and other tax-deferred accounts, tax-exempt entities, governments or government instrumentalities, S corporations, partnerships or other pass-through entities for United States federal income tax purposes or investors in such entities, insurance companies, regulated investment companies, real estate investment trusts, broker-dealers, dealers or traders in securities or currencies, certain former citizens or residents of the United States subject to section 877 of the Code, controlled foreign corporations, non-United States trusts or estates with United States beneficiaries, passive foreign investment companies, corporations that accumulate earnings to avoid United States federal income tax and taxpayers subject to the alternative minimum tax. This summary also does not discuss notes held as part of a hedge, straddle, synthetic security, constructive sale transaction or conversion transaction, situations in which the "functional currency" of a United States Holder (as defined below) is not the United States dollar or situations where a United States Holder (as defined below) holds a note through a bank, financial institution or other entity or a branch thereof, that is located, organized or resident outside the United States. Moreover, the effect of any United States federal non-income taxes (such as estate or gift taxes) and any state, local or non-United States tax laws or tax treaties are not discussed.

In the case of a beneficial owner of notes that is classified as a partnership for United States federal income tax purposes, the tax treatment of the notes to a partner in the partnership generally will depend upon the tax status of the partner and the activities of the partner and the partnership. If you are a partner of a partnership holding notes, then you should consult your own tax advisors about the United States federal income tax consequences to you of the purchase, ownership and disposition of the notes by the partnership.

The following discussion is for informational purposes only and is not a substitute for careful tax planning and advice. Investors considering the purchase of notes should consult their own tax advisors with respect to the application of the United States federal income tax laws to their particular situations, as well as any tax consequences arising under any other federal tax laws or the laws of any state, local or non-United States taxing jurisdiction or under any applicable tax treaty, and the possible effects of changes in United States federal tax laws, or in any applicable tax treaty.

#### Effect of Certain Contingencies
In certain circumstances, we may be required to pay amounts in excess of stated interest and principal on the notes. Our obligation to pay such excess amounts may implicate the provisions of the Treasury regulations relating to "contingent payment debt instruments" (CPDIs) in which case the timing and amount of income inclusions and the character of income recognized may be different from the consequences discussed herein. However, under these Treasury regulations, one or more contingencies will not cause a series of the notes to be treated as CPDIs if, as of the issue date of such series of notes, such contingencies, in the aggregate, are considered remote or incidental. Although the issue is not free from doubt, we

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intend to take the position that the possibility of payment of such excess amounts should be treated as remote and/or incidental and do not result in the notes being treated as CPDIs under applicable Treasury regulations.

Our position that these contingencies are remote or incidental is binding on a holder, unless such holder explicitly discloses to the IRS on its tax return for the taxable year during which it acquires the notes that it is taking a different position. However, this determination is inherently factual and we can give you no assurance that our position would be sustained if challenged by the IRS. A successful challenge of this position by the IRS may require a holder to accrue ordinary interest income on the notes at a rate in excess of the stated interest rate, and to treat any gain realized on the sale, exchange, redemption, retirement or other taxable disposition of the notes as ordinary income rather than capital gain. Holders of notes should consult their own tax advisors regarding the tax consequences of the notes being treated as CPDIs. The remainder of this discussion assumes that the notes will not be treated as CPDIs for United States federal income tax purposes.

#### United States Holders
The following is a summary of certain United States federal income tax considerations for a United States Holder. For purposes of this summary, the term "United States Holder" means a beneficial owner of a note that is, for United States federal income tax purposes:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • an individual who is a citizen or a resident of the United States;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • a corporation, or any other entity treated as a corporation for United States federal income tax purposes, created or organized in or under the laws of the United States, any state thereof or the District of Columbia;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • an estate, the income of which is subject to United States federal income taxation regardless of its source; or

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • a trust, if (1) a court within the United States is able to exercise primary jurisdiction over its administration and one or more "United States persons" (within the meaning of the Code) have the authority to control all of its substantial decisions, or (2) the trust has a valid election in place under applicable Treasury regulations to be treated as a domestic trust for United States federal income tax purposes.

#### Taxation of stated interest on a note
Stated interest on a note generally will be included in the gross income of a United States Holder as ordinary income at the time such interest is accrued or received, in accordance with the United States Holder's method of tax accounting for United States federal income tax purposes.

#### Sale, exchange, redemption, retirement or other taxable disposition of a note
Upon the sale, exchange, redemption, retirement or other taxable disposition of a note, a United States Holder generally will recognize gain or loss equal to the difference, if any, between (1) the amount realized on the disposition, except any portion of such amount that is attributable to accrued but unpaid interest, which will be taxed as ordinary interest income to the extent not previously so taxed, and (2) the United States Holder's adjusted tax basis in the note. A United States Holder's adjusted tax basis in a note generally will equal the cost of the note to such United States Holder, reduced by any principal payments on the note received by such United States Holder. Any such gain or loss generally will be long-term capital gain or loss if, at the time of such disposition, the United States Holder has held the note for more than one year. Individuals and other non-corporate taxpayers are, under certain circumstances, subject to United States federal income tax on long-term capital gains at a reduced tax rate. The deductibility of capital losses is subject to limitations. Each United States Holder should consult its own tax advisors as to the deductibility of capital losses in its particular circumstances.

#### Information reporting and backup withholding
In general, we must report certain information to the IRS with respect to payments of stated interest and payments of the proceeds of the sale or other taxable disposition (including a retirement or redemption)

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of a note to certain United States Holders, except in the case of an exempt recipient (such as a corporation). The payor (which may be us or an intermediate payor) will be required to impose backup withholding tax, currently at a rate of 24 percent, with respect to the foregoing amounts if (1) the payee fails to furnish a taxpayer identification number ("TIN") to the payor or to establish an exemption from backup withholding, (2) the IRS notifies the payor that the TIN furnished by the payee is incorrect, (3) there has been a notified payee underreporting described in section 3406(c) of the Code or (4) the payee has not certified under penalties of perjury that it has furnished a correct TIN, that it is a United States person and that the IRS has not notified the payee that it is subject to backup withholding under the Code. Backup withholding tax is not an additional tax. Any amounts withheld under the backup withholding rules from a payment to a United States Holder will be allowed as a credit against the holder's United States federal income tax liability, if any, and may entitle the United States Holder to a refund, provided that the required information is timely furnished to the IRS. United States Holders should consult their own tax advisors regarding the effect, if any, of the backup withholding rules on their particular circumstances.

#### Medicare contribution tax
An additional 3.8% tax will be imposed on certain United States Holders who are individuals, estates or trusts (other than certain exempt trusts or estates) on the lesser of (1) the United States Holder's "net investment income" (or undistributed net investment income in the case of an estate or trust) for the relevant taxable year and (2) the excess of the United States Holder's modified adjusted gross income (or adjusted gross income in the case of an estate or trust) for the taxable year over a certain threshold. A United States Holder's net investment income will generally include its interest income and its net gains from the disposition of notes, unless such interest income or net gains are derived in the ordinary course of the conduct of a trade or business (other than a trade or business that consists of certain passive or trading activities). If you are a United States Holder that is an individual, estate or trust, you should consult your tax advisor regarding the applicability of the Medicare contribution tax to your income and gains in respect of your investment in the notes.

#### Non-United States Holders
The following is a summary of certain United States federal income tax considerations for a non-United States Holder. For purposes of this summary, the term "non-United States Holder" means a beneficial owner of a note that is, for United States federal income tax purposes:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • a nonresident alien individual;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • a foreign corporation; or

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • a foreign estate or trust.

The following discussion assumes that no item of income, gain, deduction or loss derived by any non-United States Holder in respect of the notes at any time is effectively connected with the conduct of a United States trade or business. Non-United States Holders with any item of income, gain, deduction or loss in respect of the notes that is effectively connected with the conduct of a United States trade or business should consult their own tax advisors regarding the United States federal income and branch profits tax consequences of the purchase, ownership and disposition of the notes.

#### Payment of interest
Subject to the discussions on backup withholding and FATCA, interest paid on a note by us or any paying agent to a non-United States Holder will be exempt from United States income and withholding tax under the "portfolio interest exemption" provided that (1) the non-United States Holder does not, actually or constructively, own 10 percent or more of the total combined voting power of all classes of our stock entitled to vote, (2) the non-United States Holder is not a controlled foreign corporation related to us, actually or constructively, through stock ownership, (3) the non-United States Holder is not a bank that acquired the notes in consideration for an extension of credit made pursuant to a loan agreement entered into in the ordinary course of its trade or business and (4) either (a) the non-United States Holder provides to us or our paying agent an applicable properly completed IRS Form W-8BEN or W-8BEN-E (or applicable successor form) and any applicable attachments, signed under penalties of perjury, that includes

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its name and address and that certifies that it is not a United States person or in the case of an individual, that the person is neither a citizen or a resident (for United States federal income tax purposes) of the United States, in compliance with applicable law and regulations, or (b) a securities clearing organization, bank or other financial institution that holds customers' securities in the ordinary course of its trade or business on behalf of the non-United States Holder provides a statement to us or our agent under penalties of perjury in which it certifies that a properly completed applicable IRS Form W-8BEN or W-8BEN-E (or applicable successor form) has been received by it from the non-United States Holder or (c) the non-United States Holder holds its notes through a "qualified intermediary" and the qualified intermediary furnishes a copy to us or our agent of a properly executed IRS Form W-8IMY (or applicable successor form) and any applicable attachments on behalf of itself (which may, in some circumstances, include a withholding statement and applicable underlying IRS forms sufficient to establish that the non-United States Holder is not a United States Holder). This certification requirement may be satisfied with other documentary evidence in the case of a note held as an offshore obligation or through certain foreign intermediaries, if certain requirements are met. If a non-United States Holder cannot satisfy the requirements of the portfolio interest exemption described above, payments of interest made to such non-United States Holder generally will be subject to United States withholding tax at the rate of 30 percent, unless the non-United States Holder provides us or our agent with a properly executed IRS Form W-8BEN or W-8BEN-E or applicable successor form) establishing an exemption from, or reduction of the withholding tax under the benefit of an applicable tax treaty.

#### Sale, exchange, redemption, retirement or other disposition of a note
Subject to the discussions on backup withholding tax and FATCA below, a non-United States Holder generally will not be subject to United States federal income tax or withholding tax on any gain realized on a sale, exchange, redemption, retirement or other taxable disposition of a note (other than any amount representing accrued but unpaid interest on the note, which is subject to the rules discussed above under "— Payment of interest"). However, if a non-United States Holder is an individual who is present in the United States for 183 days or more in the taxable year of the disposition, and certain other requirements are met, such non-United States Holder generally will be subject to United States federal income tax at a flat rate of 30 percent (unless a lower applicable treaty rate applies) on any such non-United States Holder's United States-source gain, which may be offset by certain United States-source losses.

#### Information reporting and backup withholding
The amount of interest on a note paid to a non-United States Holder and the amount of tax, if any, withheld from such payment generally must be reported annually to the non-United States Holder and to the IRS. The IRS may make this information available under the provisions of an applicable income tax treaty to the tax authorities in the country in which the non-United States Holder is resident.

Provided that a non-United States Holder has complied with certain reporting procedures (usually satisfied by providing an applicable properly completed IRS Form W-8BEN or IRS Form W-8BEN-E) or otherwise establishes an exemption, the non-United States Holder generally will not be subject to backup withholding tax with respect to interest payments on, and the proceeds from a disposition of, a note, unless we or our paying agent know or have reason to know that the holder is a United States person. Rules relating to information reporting requirements and backup withholding with respect to the payment of proceeds from the taxable disposition (including a redemption or retirement) of a note are as follows:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • If the proceeds are paid to or through the United States office of a broker, a non-United States Holder generally will be subject to backup withholding and information reporting unless the non-United States Holder certifies under penalties of perjury that it is not a United States person (usually on an IRS Form W-8BEN or W-8BEN-E) or otherwise establishes an exemption.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • If the proceeds are paid to or through a non-United States office of a broker that is not a United States person and does not have certain specified United States connections (a "United States Related Person"), a non-United States Holder will not be subject to backup withholding or information reporting.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • If the proceeds are paid to or through a non-United States office of a broker that is a United States person or a United States Related Person, a non-United States Holder generally will be subject to

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information reporting (but generally not backup withholding) unless the non-United States Holder certifies under penalties of perjury that it is not a United States person (usually on an IRS Form W-8BEN) or otherwise establishes an exemption.

Backup withholding is not an additional tax. Any amounts withheld under the backup withholding rules will be allowed as a credit against the non-United States Holder's United States federal income tax liability, if any, and may entitle the non-United States Holder to a refund, provided that the required information is timely furnished to the IRS. Non-United States Holders should consult their own tax advisors regarding the application of the backup withholding rules in their particular circumstances and the availability of, and procedure for, obtaining an exemption from backup withholding under current Treasury regulations.

#### "FATCA" legislation
The Hiring Incentives to Restore Employment Act and the final Treasury regulations and official IRS guidance associated with such provisions (such provisions, regulations and guidance commonly known as FATCA) generally imposes a United States federal withholding tax of 30 percent on interest income paid on a debt obligation to (1) a foreign financial institution (as the beneficial owner or as an intermediary for the beneficial owner), unless such institution (a) enters into, and is in compliance with, a withholding and information reporting agreement with the United States government to collect and provide to the United States tax authorities substantial information regarding United States account holders of such institution (which would include certain equity and debt holders of such institution, as well as certain account holders that are foreign entities with United States owners) or (b) is a resident in a country that has entered into an intergovernmental agreement with the United States in relation to such withholding and information reporting and the financial institution complies with the related information reporting requirements of such country or (2) a foreign entity that is not a financial institution (as the beneficial owner or as an intermediary for the beneficial owner), unless such entity provides the withholding agent with a certification identifying the substantial United States owners of the entity, which generally includes any United States person who directly or indirectly owns more than 10 percent of the entity or certifies that it does not have any substantial United States owners. The IRS has issued proposed regulations (on which taxpayers may rely until final regulations are issued) that would generally not apply these withholding requirements to gross proceeds from the disposition of assets such as the notes.

Investors should consult with their own tax advisors regarding the implications of this legislation on their investment in our notes.

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#### UNDERWRITING (CONFLICTS OF INTEREST)
Barclays Capital Inc., Citigroup Global Markets Inc., Goldman Sachs & Co. LLC, J.P. Morgan Securities LLC, and Morgan Stanley & Co. LLC are acting as representatives of the underwriters set forth below. Subject to the terms and conditions contained in an underwriting agreement between us and the underwriters, we have agreed to sell to the underwriters and the underwriters have severally agreed to purchase from us, the principal amount of the notes listed opposite their names below:

---

| | | |
|:---|:---|:---|
| **Underwriter**  | **Principal <br> Amount of <br> 20 Notes**  | **Principal <br> Amount of <br> 20 Notes**  |
| Barclays Capital Inc.  | $— | $|
| Citigroup Global Markets Inc.  |  |  |
| Goldman Sachs & Co. LLC  |  |  |
| J.P. Morgan Securities LLC  |  |  |
| Morgan Stanley & Co. LLC  |  |  |
| MUFG Securities Americas Inc.  |  |  |
| PNC Capital Markets LLC  |  |  |
| SMBC Nikko Securities America, Inc.  |  |  |
| Wells Fargo Securities, LLC  |  |  |
| Loop Capital Markets LLC  |  |  |
| Siebert Williams Shank & Co., LLC  |  |  |
| Huntington Securities, Inc.  |  |  |
| &nbsp;&nbsp;&nbsp; **Total**  | $— | $|

---

The obligations of the several underwriters to purchase the notes are subject to certain conditions as set forth in the underwriting agreement. The underwriters are obligated to purchase all of the notes if they purchase any of the notes. The underwriting agreement also provides that if an underwriter defaults, the purchase commitments of the non-defaulting underwriter may be increased or the offering of notes may be terminated. The offering of the notes by the underwriters is subject to receipt and acceptance and subject to the underwriters' right to reject any order in whole or in part.

The underwriters have advised us that they propose to initially offer the notes to the public at the relevant price to public appearing on the cover page of this prospectus supplement and may also offer the notes to certain securities dealers at the relevant price to public on the cover of this prospectus supplement less a concession of % of the principal amount of the 20 notes, of % of the principal amount of the 20 notes and % of the principal amount of the 20 notes. The underwriters may allow, and such dealers may re-allow, a discount to certain brokers and dealers not in excess of % of the principal amount of the 20 notes, of % of the principal amount of the 20 notes and % of the principal amount of the 20 notes. After the initial public offering, the relevant price to public, concession and discount may be changed.

There is no established trading market for the notes, and the underwriters are not obligated to make a market in the notes. We do not intend to apply for listing of the notes on any securities exchange. The underwriters have advised us that they intend to make a market in the notes but are not obligated to do so and may discontinue such market-making activities at any time without notice. We cannot give any assurance as to the maintenance of the trading market for, or the liquidity of, the notes, the ability of the holders to sell their notes or the price at which holders will be able to sell their notes.

In connection with the offering, the underwriters may engage in transactions that stabilize the price of the notes. These transactions may include purchases for the purpose of fixing or maintaining the price of the notes.

The underwriters may create a short position in the notes in connection with the offering. That means they sell a larger principal amount of the notes than is shown on the cover page of this prospectus supplement. If they create a short position, the underwriters may purchase notes in the open market to reduce the short position.

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If the underwriters purchase the notes to stabilize the price or to reduce their short position, the price of the notes could be higher than it might be if they had not made such purchases. The underwriters make no representation or prediction about any effect that purchases may have on the price of the notes and any of such transactions may be discontinued at any time.

The underwriters also may impose a penalty bid. This occurs when a particular underwriter repays to the underwriters a portion of the underwriting discount received by it because the underwriters or their affiliates have repurchased notes sold by or for the account of such underwriter in stabilizing or short covering transactions.

We have agreed to indemnify the several underwriters against certain civil liabilities, including liabilities under the Securities Act of 1933, or to contribute with respect to payments which the underwriters may be required to make in respect of any of those liabilities.

Our expenses associated with the offer and sale of the notes, excluding underwriting discounts, are estimated to be approximately $.

The underwriters and their respective affiliates are full service financial institutions engaged in various activities. From time to time, in the ordinary course of business, the underwriters and their respective affiliates have engaged and may in the future engage, in sales and trading, commercial banking, investment banking advisory, investment management, investment research, principal investment, hedging, market making, brokerage and other financial and non-financial activities and services and/or other transactions of a financial nature with us and our affiliates. Consequently, they have received, and in the future may continue to receive, customary fees and commissions for these services. The underwriters or their affiliates may provide credit to us or our affiliates as lenders from time to time, including under our existing revolving credit facility. As described in "Use of Proceeds," the Company intends to use a portion of the net proceeds of this offering to repay $850,000,000 of Exelon's outstanding term loans. Banking affiliates of two of the underwriters of this offering, SMBC Nikko Securities America, Inc. and PNC Capital Markets LLC, are lenders to the Company for a portion of the $850,000,000 of Exelon's outstanding term loans to be repaid with the net proceeds from the sale of the notes. These payments represent conflicts of interest under FINRA Rule 5121. See "Underwriting (Conflict of Interest) — Conflict of Interest."

In addition, in the ordinary course of their business activities, the underwriters and their affiliates may make or hold a broad array of investments and actively trade debt and equity securities (or related derivative securities) and financial instruments (including bank loans) for their own account and for the accounts of their customers. Such investments and securities activities may involve securities and/or instruments of ours or our affiliates. If any of the underwriters or their affiliates have a lending relationship with us, certain of those underwriters or their affiliates routinely hedge, and certain other of those underwriters or their affiliates may hedge, their credit exposure to us consistent with their customary risk management policies. Typically, such underwriters and their affiliates would hedge such exposure by entering into transactions which consist of either the purchase of credit default swaps or the creation of short positions in our securities, including potentially the notes offered hereby. Any such credit default swaps or short positions could adversely affect future trading prices of the notes offered hereby. The underwriters and their affiliates may also make investment recommendations and/or publish or express independent research views in respect of such securities or financial instruments and may hold, or recommend to clients that they acquire, long and/or short positions in such securities and instruments.

#### Conflicts of Interest
A portion of the net proceeds of this offering will be paid to an affiliate of SMBC Nikko Securities America, Inc., an underwriter in this offering, and to an affiliate of PNC Capital Markets LLC, an underwriter in this offering, in connection with the repayment of the $850,000,000 of Exelon's outstanding term loans maturing in July 2023. Because these payments represent at least 5% of the net offering proceeds, SMBC Nikko Securities America, Inc. and PNC Capital Markets LLC are deemed to have a "conflict of interest" under FINRA Rule 5121. The appointment of a "qualified independent underwriter" is not required in connection with this offering as the securities offered are investment grade rated in accordance with Rule 5121, exists for the notes. In accordance with Rule 5121, SMBC Nikko Securities America, Inc. and

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PNC Capital Markets LLC will not confirm any sales to any account over which either exercises discretionary authority without the specific written approval of the transaction from the account holder. See "Use of Proceeds."

#### European Economic Area
The notes may not be offered, sold or otherwise made available to any retail investor in the EEA. For the purposes of this provision:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; (a)

the expression "retail investor" means a person who is one (or more) of the following:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; (i)

a retail client as defined in point (11) of Article 4(1) of MiFID II; or

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; (ii)

a customer within the meaning of the Insurance Distribution Directive, where that customer would not qualify as a professional client as defined in point (10) of Article 4(1) of MiFID II; or

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; (iii)

not a qualified investor as defined in the Prospectus Regulation; and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; (b)

the expression "offer" includes the communication in any form and by any means of sufficient information on the terms of the offer and the notes to be offered so as to enable an investor to decide to purchase or subscribe for the notes.

#### United Kingdom
The notes may not be offered, sold or otherwise made available to any retail investor in the United Kingdom. For the purposes of this provision:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; (a)

the expression "retail investor" means a person who is one (or more) of the following:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; (i)

a retail client, as defined in point (8) of Article 2 of Regulation (EU) No 2017/565 as it forms part of domestic law in the United Kingdom by virtue of the EUWA; or

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; (ii)

a customer within the meaning of the provisions of the FSMA and any rules or regulations made under the FSMA to implement the Insurance Distribution Directive, where that customer would not qualify as a professional client, as defined in point (8) of Article 2(1) of Regulation (EU) No 600/2014 as it forms part of domestic law in the United Kingdom by virtue of the EUWA; or

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; (iii)

not a qualified investor as defined in Article 2 of the UK Prospectus Regulation; and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; (b)

the expression "offer" includes the communication in any form and by any means of sufficient information on the terms of the offer and the notes to be offered so as to enable an investor to decide to purchase or subscribe for the notes.

#### Other Regulatory Restrictions in the United Kingdom
Any invitation or inducement to engage in investment activity (within the meaning of Section 21 of the FSMA) in connection with the issue or sale of the notes may only be communicated or caused to be communicated in circumstances in which Section 21(1) of the FSMA does not apply to Exelon.

All applicable provisions of the FSMA must be complied with in respect to anything done by any person in relation to the notes in, from or otherwise involving the United Kingdom.

#### Canada
The notes may be sold only to purchasers purchasing, or deemed to be purchasing, as principal that are accredited investors, as defined in National Instrument 45-106 Prospectus Exemptions or subsection 73.3(1) of the Securities Act (Ontario), and are permitted clients, as defined in National Instrument 31-103 Registration Requirements, Exemptions and Ongoing Registrant Obligations. Any resale of the notes must

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be made in accordance with an exemption from, or in a transaction not subject to, the prospectus requirements of applicable securities laws.

Securities legislation in certain provinces or territories of Canada may provide a purchaser with remedies for rescission or damages if this prospectus supplement (including any amendment thereto) contains a misrepresentation, provided that the remedies for rescission or damages are exercised by the purchaser within the time limit prescribed by the securities legislation of the purchaser's province or territory. The purchaser should refer to any applicable provisions of the securities legislation of the purchaser's province or territory for particulars of these rights or consult with a legal advisor.

Pursuant to section 3A.3 of National Instrument 33-105 Underwriting Conflicts (NI 33-105), the underwriters are not required to comply with the disclosure requirements of NI 33-105 regarding underwriter conflicts of interest in connection with this offering.

#### Hong Kong
The notes have not been offered or sold or will not be offered or sold by means of any document other than (i) to "professional investors" as defined in the Securities and Futures Ordinance (Cap.571, Laws of Hong Kong) (the "SFO") and any rules made thereunder, or (ii) in other circumstances which do not result in the document being a "prospectus" as defined in the Companies (Winding Up and Miscellaneous Provisions) Ordinance (Cap.32, Laws of Hong Kong) (the "Ordinance") or which do not constitute an offer to the public within the meaning of the Ordinance, and no advertisement, invitation or document relating to the notes has been or will be issued or has been or may be in the possession of any person for the purpose of issue (in each case whether in Hong Kong or elsewhere), which is directed at, or the contents of which are likely to be accessed or read by, the public in Hong Kong (except if permitted to do so under the securities laws of Hong Kong) other than with respect to notes which are or are intended to be disposed of only to persons outside Hong Kong or only to "professional investors" within the meaning of the SFO and any rules made thereunder.

The contents of this prospectus supplement and the accompanying prospectus have not been reviewed by any regulatory authority in Hong Kong. You are advised to exercise caution in relation to the offer. If you are in any doubt about any of the contents of this prospectus supplement and the accompanying prospectus, you should obtain independent professional advice.

#### Japan
The notes have not been and will not be registered under the Financial Instruments and Exchange Law of Japan (Law No. 25 of 1948, as amended, the "FIEA") and each underwriter has agreed that it will not offer or sell any securities, directly or indirectly, in Japan or to, or for the account or the benefit of, any resident of Japan (which term as used herein means any person resident in Japan, including any corporation or other entity organized under the laws of Japan), or to others for re-offering or resale, directly or indirectly, in Japan or to, or for the account or the benefit of, any resident of Japan, except pursuant to an exemption from the registration requirements of, and otherwise in compliance with, the FIEA and any other applicable laws, regulations and ministerial guidelines of Japan.

#### Singapore
This prospectus supplement and the accompanying prospectus have not been registered as a prospectus under the Securities and Futures Act, Chapter 289 of Singapore (the "SFA") by the Monetary Authority of Singapore, and the offer of the notes in Singapore is made primarily pursuant to the exemptions under Sections 274 and 275 of the SFA. Accordingly, the notes may not be offered or sold, or made the subject of an invitation for subscription or purchase, nor may this prospectus supplement and the accompanying prospectus or any other document or material in connection with the offer or sale, or invitation for subscription or purchase of the notes be circulated or distributed, whether directly or indirectly, to any person in Singapore other than (i) to an institutional investor as defined in Section 4A of the SFA ("Institutional Investor") pursuant to Section 274 of the SFA, (ii) to an accredited investor as defined in Section 4A of the SFA (an "Accredited Investor") or other relevant person as defined in Section 275(2) of the SFA (a "Relevant Person"), or to any person pursuant to an offer referred to in Section 275(1A) of the SFA and

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(where applicable) Regulation 3 of the Securities and Futures (Classes of Investors) Regulations 2018, and in accordance with the conditions, specified in Section 275 of the SFA or (iii) otherwise pursuant to, and in accordance with the conditions of, any other applicable exemption or provision of the SFA.

It is a condition of the offer that where the notes are subscribed or purchased pursuant to an offer made in reliance on Section 275 by a Relevant Person which is:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; (a)

a corporation (which is not an Accredited Investor) the sole business of which is to hold investments and the entire share capital of which is owned by one or more individuals, each of whom is an Accredited Investor; or

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; (b)

a trust (where the trustee is not an Accredited Investor) whose sole purpose is to hold investments and each beneficiary is an Accredited Investor,

the shares, debentures and units of shares and debentures of that corporation, and the beneficiaries' rights and interest (howsoever described) in that trust shall not be transferred within six months after that corporation or that trust has subscribed for or acquired the notes except:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; (1)

to an Institutional Investor, or an Accredited Investor or other Relevant Person, or which arises from any offer referred to in Section 275(1A) of the SFA (in the case of that corporation) or Section 276(4)(i)(B) of the SFA (in the case of that trust);

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; (2)

where no consideration is or will be given for the transfer;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; (3)

where the transfer is by operation of law; or

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; (4)

as specified in Section 276(7) of the SFA; or (E) as specified in Regulation 37A of the Securities and Futures (Offers of Investments) (Securities and Securities-based Derivatives Contracts) Regulations 2018 of Singapore. Solely for the purposes of our obligations pursuant to Sections 309B(1)(a) and 309B(1)(c) of the SFA, we have determined, and hereby notify all relevant persons (as defined in Section 309A(1) of the SFA) that the notes are "prescribed capital markets products" (as defined in the Securities and Futures (Capital Markets Products) Regulations 2018 of Singapore) and Excluded Investment Products (as defined in MAS Notice SFA 04-N12: Notice on the Sale of Investment Products and MAS Notice FAA-N16: Notice on Recommendations on Investment Products).

*Singapore Securities and Futures Act Product Classification* — Solely for the purposes of its obligations pursuant to Sections 309B(1)(a) and 309B(1)(c) of the SFA, the Company has determined, and hereby notifies all relevant persons (as defined in Section 309A of the SFA) that the notess are prescribed capital markets products (as defined in Section 309B(10) of the SFA) and excluded investment products (as defined in MAS Notice SFA 04-N12: Notice on the Sale of Investment Products and MAS Notice FAA-N16: Notice on Recommendations on Investment Products).

#### Switzerland
Notice to Prospective Investors in Switzerland

This prospectus supplement is not intended to constitute an offer or solicitation to purchase or invest in the notes. The notes may not be publicly offered, directly or indirectly, in Switzerland within the meaning of the Swiss Financial Services Act ("FinSA") and no application has or will be made to admit the notes to trading on any trading venue (exchange or multilateral trading facility) in Switzerland. Neither this prospectus supplement nor any other offering or marketing material relating to the notes constitutes a prospectus pursuant to the FinSA, and neither this prospectus supplement nor any other offering or marketing material relating to the notes may be publicly distributed or otherwise made publicly available in Switzerland.

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#### Taiwan
The notes have not been and will not be registered with the Financial Supervisory Commission of Taiwan pursuant to relevant securities laws and regulations and may not be sold, issued or offered within Taiwan through a public offering or in circumstances which constitutes an offer within the meaning of the Securities and Exchange Act of Taiwan that requires a registration or approval of the Financial Supervisory Commission of Taiwan. No person or entity in Taiwan has been authorized to offer, sell, give advice regarding or otherwise intermediate the offering and sale of the notes in Taiwan.

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#### LEGAL MATTERS
Ballard Spahr LLP will render an opinion as to the validity of the notes for us. Certain legal matters will be passed on for the underwriters by Winston & Strawn LLP, Chicago, Illinois. Winston & Strawn LLP provides legal services to Exelon and its subsidiaries from time to time.

#### EXPERTS
The financial statements and management's assessment of the effectiveness of internal control over financial reporting (which is included in Management's Report on Internal Control over Financial Reporting) of Exelon Corporation incorporated in this prospectus supplement by reference to the Annual Report on Form 10-K for the year ended December 31, 2022 have been so incorporated in reliance on the report of PricewaterhouseCoopers LLP, an independent registered public accounting firm, given on the authority of said firm as experts in auditing and accounting.

#### WHERE YOU CAN FIND MORE INFORMATION
We file annual, quarterly and current reports, information statements and other information with the SEC. You may read and copy any document we have filed or will file with the SEC at the SEC's public website (www.sec.gov).

Information about us is also available on Exelon's web site at http://www.exeloncorp.com. This web site and the SEC's web site above are intended to be inactive textual references only. Information on Exelon's or the SEC's web site (other than the documents incorporated by reference) is not a part of this prospectus supplement.

#### DOCUMENTS INCORPORATED BY REFERENCE
The SEC allows us to "incorporate by reference" information that we file with the SEC, which means that we can disclose important information to you by referring you to the documents we file with the SEC. The information incorporated by reference is an important part of this prospectus, and information that we file later with the SEC will automatically update and supersede this information. This incorporation by reference does not include documents that are furnished but not filed with the SEC. We incorporate by reference the documents listed below and any future documents that we file with the SEC under Section 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934, as amended (known as the Exchange Act) but prior to the termination of any offering of securities made by this prospectus:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • [Exelon's Annual Report on Form 10-K for the year ended December](https://www.sec.gov/ix?doc=/Archives/edgar/data/8192/000110935723000018/exc-20221231.htm)[31](https://www.sec.gov/ix?doc=/Archives/edgar/data/8192/000110935723000018/exc-20221231.htm)[, 2022;](https://www.sec.gov/ix?doc=/Archives/edgar/data/8192/000110935723000018/exc-20221231.htm) and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • [Exelon's Current Report on Form 8-K filed with the SEC on February 1, 2023.](https://www.sec.gov/ix?doc=/Archives/edgar/data/22606/000110935723000007/exc-20230201.htm)

You can also find more information about us from the sources described under "Documents Incorporated by Reference" in the accompanying prospectus.

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### EXELON CORPORATION

#### Debt Securities Common Stock Stock Purchase Contracts Stock Purchase Units Preferred Stock Depositary Shares

#### COMMONWEALTH EDISON COMPANY Debt Securities

#### PECO ENERGY COMPANY Debt Securities

#### BALTIMORE GAS AND ELECTRIC COMPANY Debt Securities

#### POTOMAC ELECTRIC POWER COMPANY Debt Securities

#### DELMARVA POWER & LIGHT COMPANY Debt Securities

#### ATLANTIC CITY ELECTRIC COMPANY Debt Securities
Exelon Corporation (Exelon) may use this prospectus to offer and sell from time to time:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • debt securities;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • common stock;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • stock purchase contracts;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • stock purchase units;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • preferred stock in one or more series;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • depositary shares.

Commonwealth Edison Company (ComEd) may use this prospectus to offer and sell from time to time:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • debt securities

PECO Energy Company (PECO) may use this prospectus to offer and sell from time to time:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • debt securities

Baltimore Gas and Electric Company (BGE) may use this prospectus to offer and sell from time to time:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • debt securities

Potomac Electric Power Company (Pepco) may use this prospectus to offer and sell from time to time:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • debt securities

Delmarva Power & Light Company (DPL) may use this prospectus to offer and sell from time to time:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • debt securities

Atlantic City Electric Company (ACE) may use this prospectus to offer and sell from time to time:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • debt securities

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Exelon, ComEd, PECO, BGE, Pepco, DPL and ACE sometimes refer to the securities listed above as the "Securities."

Exelon, ComEd, PECO, BGE, Pepco, DPL and ACE will provide the specific terms of the Securities in supplements to this prospectus prepared in connection with each offering. Please read this prospectus and the applicable prospectus supplement carefully before you invest. This prospectus may not be used to consummate sales of the offered Securities unless accompanied by a prospectus supplement.

Exelon's common shares are listed on the Nasdaq Stock Market LLC, under the symbol "EXC."

 **Please see "Risk Factors" beginning on page [2](#tRIFA2) for a discussion of factors you should consider in connection with a purchase of the Securities offered in this prospectus.** 

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of the Securities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

#### The date of this prospectus is August 3, 2022.

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#### **TABLE OF CONTENTS**

---

| | |
|:---|:---|
| | **Page**  |
| [ABOUT THIS PROSPECTUS](#tATP2)  | [1](#tATP2) |
| [FORWARD-LOOKING STATEMENTS](#tFOST2)  | [1](#tFOST2) |
| [RISK FACTORS](#tRIFA2)  | [2](#tRIFA2) |
| [EXELON CORPORATION](#tEXCO2)  | [2](#tEXCO2) |
| [COMMONWEALTH EDISON COMPANY](#tCEC2)  | [2](#tCEC2) |
| [PECO ENERGY COMPANY](#tPEC2)  | [2](#tPEC2) |
| [BALTIMORE GAS AND ELECTRIC COMPANY](#tBGAE2)  | [3](#tBGAE2) |
| [POTOMAC ELECTRIC POWER COMPANY](#tPEPC2)  | [3](#tPEPC2) |
| [DELMARVA POWER & LIGHT COMPANY](#tDPLC2)  | [3](#tDPLC2) |
| [ATLANTIC CITY ELECTRIC COMPANY](#tACEC2)  | [3](#tACEC2) |
| [USE OF PROCEEDS](#tUOP2)  | [3](#tUOP2) |
| [DESCRIPTION OF SECURITIES](#tDOS2)  | [3](#tDOS2) |
| [PLAN OF DISTRIBUTION](#tPOD2)  | [3](#tPOD2) |
| [LEGAL MATTERS](#tLEMA2)  | [5](#tLEMA2) |
| [EXPERTS](#tEXP2)  | [5](#tEXP2) |
| [WHERE YOU CAN FIND MORE INFORMATION](#tWYCF2)  | [6](#tWYCF2) |
| [DOCUMENTS INCORPORATED BY REFERENCE](#tDIBR2)  | [6](#tDIBR2) |

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#### ABOUT THIS PROSPECTUS
This prospectus is part of a registration statement that Exelon, ComEd, PECO, BGE, Pepco, DPL and ACE have each filed with the Securities and Exchange Commission (SEC) using a "shelf" registration process. Under this shelf registration process, each of us may, from time to time, sell our Securities described in this prospectus in one or more offerings. Each time Exelon, ComEd, PECO, BGE, Pepco, DPL or ACE (each, a registrant) sells Securities, the registrant will provide a prospectus supplement that will contain a description of the Securities the registrant will offer and specific information about the terms of the offering. The prospectus supplement may also add, update or change information contained in this prospectus. If there is any inconsistency between the information in this prospectus and the prospectus supplement, you should rely on the prospectus supplement. You should read both this prospectus and any prospectus supplement together with additional information described under "Where You Can Find More Information."

Information contained herein relating to each registrant is filed separately by such registrant on its own behalf. No registrant makes any representation as to information relating to any other registrant or Securities issued by any other registrant.

As used in this prospectus, the terms "we," "our" and "us" generally refer to:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • Exelon with respect to Securities issued by Exelon.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • ComEd with respect to Securities issued by ComEd.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • PECO with respect to Securities issued by PECO.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • BGE with respect to Securities issued by BGE.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • Pepco with respect to Securities issued by Pepco.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • DPL with respect to Securities issued by DPL.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • ACE with respect to Securities issued by ACE.

 **None of the registrants will guarantee or provide other credit or funding support for the Securities to be offered by another registrant pursuant to this prospectus.** 

We are not offering the Securities in any state where the offer is not permitted.

For more detailed information about the Securities, you should read the exhibits to the registration statement. Those exhibits have either been filed with the registration statement or incorporated by reference to earlier SEC filings listed in the registration statement.

 **You should rely only on information contained in this prospectus and which is incorporated by reference or the documents to which we have referred you. We have not authorized anyone to provide you with information that is different. This prospectus and related prospectus supplement may be used only where it is legal to sell these securities. The information in this prospectus and any prospectus supplement may only be accurate on the date of this document. The business of the registrant, financial condition, results of operations and prospects may have changed since that date.** 

 **Please see "Risk Factors" beginning on page 2 for a discussion of factors you should consider in connection with a purchase of the Securities offered in this prospectus.** 

#### FORWARD-LOOKING STATEMENTS
This prospectus and the documents incorporated or deemed incorporated by reference as described under the heading "Where You Can Find More Information" contain forward-looking statements that are not based entirely on historical facts and are subject to risks and uncertainties. Words such as "believes," "anticipates," "expects," "intends," "plans," "predicts" and "estimates" and similar expressions are intended to identify forward-looking statements but are not the only means to identify those statements. These forward-looking statements are based on assumptions, expectations and assessments made by our management in light of their experience and their perception of historical trends, current conditions, expected future developments and other factors they believe to be appropriate. Any forward-looking statements are not guarantees of our future performance and are subject to risks and uncertainties.

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This prospectus contains certain forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, which are subject to risks and uncertainties. The factors that could cause actual results to differ materially from the forward-looking statements made by Exelon, ComEd, PECO, BGE, Pepco, DPL and ACE include those factors discussed herein, as well as the items discussed in (1) the combined 2021 Annual Report on Form 10-K of Exelon, ComEd, PECO, BGE, Pepco, DPL and ACE in ITEM 1A. Risk Factors; (2) the registrants' combined Current Report on Form 8-K filed on June 30, 2022 (recasting certain portions of the combined 2021 Annual Report on Form 10-K) in (a) ITEM 7. Management's Discussion and Analysis of Financial Condition and Results of Operations and (b) ITEM 8. Financial Statements and Supplementary Data: Note 17, Commitments and Contingencies; and (3) other factors discussed in filings with the SEC by each of the registrants.

You are cautioned not to place undue reliance on these forward-looking statements, which apply only as of the date on the front of this prospectus or, as the case may be, as of the date on which we make any subsequent forward-looking statement that is deemed incorporated by reference. We do not undertake any obligation to update or revise any forward-looking statement to reflect events or circumstances after the date as of which any such forward-looking statement is made.

#### RISK FACTORS
Investing in the Securities involves various risks. You are urged to read and consider the risk factors described in (a) the combined [Annual Report on Form 10-K of Exelon, ComEd, PECO, BGE, Pepco, DPL and ACE for the year ended December 31, 2021, filed with the SEC on February 25, 2022](https://www.sec.gov/ix?doc=/Archives/edgar/data/8192/000110935722000039/exc-20211231.htm). Before making an investment decision, you should carefully consider these risks as well as other information we include or incorporate by reference in this prospectus. The prospectus supplement applicable to each type or series of Securities offered by one of the registrants will contain a discussion of additional risks applicable to an investment in such registrant and the particular type of Securities the registrant is offering under that prospectus supplement.

#### EXELON CORPORATION
Exelon, incorporated in Pennsylvania in February 1999, is a utility services holding company engaged through ComEd, PECO, BGE, Pepco, DPL and ACE, in the energy distribution and transmission businesses. Exelon's principal executive offices are located at 10 South Dearborn Street, Chicago, Illinois 60603, and its telephone number is 800-483-3220.

#### COMMONWEALTH EDISON COMPANY
ComEd's energy delivery business consists of the purchase and regulated retail sale of electricity and the transmission and distribution of electricity to retail customers in northern Illinois, including the City of Chicago.

ComEd was organized in the State of Illinois in 1913 as a result of the merger of Cosmopolitan Electric Company into the original corporation named Commonwealth Edison Company, which was incorporated in 1907. ComEd's principal executive offices are located at 10 South Dearborn Street, Chicago, Illinois 60603, and its telephone number is 312-394-4321.

#### PECO ENERGY COMPANY
PECO's energy delivery business consists of the purchase and regulated retail sale of electricity and the provision of transmission and distribution services to retail customers in southeastern Pennsylvania, including the City of Philadelphia, as well as the purchase and regulated retail sale of natural gas and the provision of natural gas distribution services to retail customers in the Pennsylvania counties surrounding the City of Philadelphia.

PECO was incorporated in Pennsylvania in 1929. PECO's principal executive offices are located at 2301 Market Street, Philadelphia, Pennsylvania 19103, and its telephone number is 215-841-4000.

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#### BALTIMORE GAS AND ELECTRIC COMPANY
BGE's energy delivery business consists of the purchase and regulated retail sale of electricity and natural gas and the transmission and distribution of electricity and distribution of natural gas to retail customers in central Maryland, including the City of Baltimore.

BGE was incorporated in Maryland in 1906. BGE's principal executive offices are located at 110 West Fayette Street, Baltimore, Maryland 21201, and its telephone number is 410-234-5000.

#### POTOMAC ELECTRIC POWER COMPANY
Pepco's energy delivery business consists of the purchase and regulated retail sale of electricity and the transmission and distribution of electricity to retail customers in the District of Columbia and major portions of Prince George's County and Montgomery County in Maryland.

Pepco was incorporated in the District of Columbia in 1896 and Virginia in 1949. Pepco's principal executive offices are located at 701 Ninth Street, N.W., Washington, D.C. 20068, and its telephone number is (202) 872-2000.

#### DELMARVA POWER & LIGHT COMPANY
DPL's energy delivery business consists of the purchase and regulated retail sale of electricity and the transmission and distribution of electricity to retail customers in portions of Delaware and Maryland, and the purchase and regulated retail sale of natural gas and distribution of natural gas to retail customers in portions of New Castle County in Delaware.

DPL was incorporated in Delaware in 1909 and Virginia in 1979. DPL's principal executive offices are located at 500 North Wakefield Drive Newark, Delaware 19702, and its telephone number is (202) 872-2000.

#### ATLANTIC CITY ELECTRIC COMPANY
ACE's energy delivery business consists of the purchase and regulated retail sale of electricity and the transmission and distribution of electricity to retail customers in portions of southern New Jersey.

ACE was incorporated in New Jersey in 1924. ACE's principal executive offices are located at 500 North Wakefield Drive Newark, Delaware 19702, and its telephone number is (202) 872-2000.

#### USE OF PROCEEDS
Except as otherwise indicated in the applicable prospectus supplement, each registrant expects to use the net proceeds from the sale of the Securities for general corporate purposes, including to discharge or refund (by redemption, by purchase on the open market, by purchase in private transactions, by tender offer or otherwise) outstanding long-term debt. Each registrant will describe in the applicable prospectus supplement any specific allocation of the proceeds to a particular purpose that the registrant has made at the date of that prospectus supplement. Please refer to our annual and quarterly reports incorporated by reference into this prospectus and any prospectus supplement for information concerning each registrant's outstanding long-term debt. See "Where You Can Find More Information.

#### DESCRIPTION OF SECURITIES
Each time one of the registrants sells securities, it will provide a prospectus supplement that will contain specific information about the terms of that offering. The prospectus supplement may also add, update or change information contained in this prospectus. You should read both this prospectus and any prospectus supplement together with additional information described under "Where You Can Find More Information."

#### PLAN OF DISTRIBUTION
We may sell the Securities offered (a) through agents; (b) by underwriters or dealers; (c) directly to one or more purchasers; or (d) through a combination of any of these methods of sale.

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In some cases we may also repurchase the Securities and reoffer them to the public by one or more of the methods described above.

This prospectus may be used in connection with any offering of securities through any of these methods or other methods described in the applicable prospectus supplement.

Any underwriter or agent involved in the offer and sale of the Securities will be named in the applicable prospectus supplement.

#### By Agents
Offered securities may be sold on a one time or a continuing basis by agents designated by the applicable registrant. The agents will use their reasonable efforts to solicit purchases for the period of their appointment under the terms of an agency agreement between the agents and the applicable issuer.

#### By Underwriters or Dealers
If underwriters are used in the sale, the underwriters may be designated by the applicable registrant or selected through a bidding process. The securities will be acquired by the underwriters for their own account. The underwriters may resell the Securities in one or more transactions, including negotiated transactions, at a fixed public offering price or at varying prices determined at the time of sale. Underwriters may sell the Securities to or through dealers, and such dealers may receive compensation in the form of discounts, concessions or commissions from the underwriters and/or commissions from the purchasers for whom they may act as agents. The obligations of the underwriters to purchase the Securities will be subject to certain conditions. The underwriters will be obligated to purchase all the Securities of the series offered if any of the securities are purchased. Any initial public offering price and any discounts or concessions allowed or re-allowed or paid to dealers may be changed from time to time.

Only underwriters named in the applicable prospectus supplement are deemed to be underwriters in connection with the Securities offered hereby.

If dealers are utilized in the sale of the Securities, the applicable registrant will sell the Securities to the dealers as principals. The dealers may then resell the Securities to the public at varying prices to be determined by such dealers at the time of resale. The names of the dealers and the terms of the transaction will be set forth in the applicable prospectus supplement.

#### Direct Sales
We may also sell Securities directly to the public. In this case, no underwriters or agents would be involved.

#### General Information
We may authorize agents, underwriters or dealers to solicit offers by certain institutions to purchase Securities from us at the public offering price pursuant to delayed delivery contracts providing for payment and delivery on a later date or dates, all as described in the applicable prospectus supplement. Each delayed delivery contract will be for an amount not less than, and the aggregate amount of the Securities shall be not less nor more than, the respective amounts stated in the applicable prospectus supplement. Such institutions may include commercial and savings banks, insurance companies, pension funds, investment companies, educational and charitable institutions, and other institutions, but will in all cases be subject to our approval. The delayed delivery contracts will not be subject to any conditions except:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • the purchase by an institution of the Securities covered by its delayed delivery contract shall not, at any time of delivery, be prohibited under the laws of any jurisdiction in the United States to which such delayed delivery contract is subject; and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • if the Securities are being sold to underwriters, we shall have sold to those underwriters the total amount of the Securities less the amount thereof covered by the delayed delivery contracts. The underwriters will not have any responsibility in respect of the validity or performance of the delayed delivery contracts.

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Unless otherwise specified in the related prospectus supplement, each series of the Securities will be a new issue with no established trading market, other than the common stock. Any common stock sold pursuant to a prospectus supplement or issuable upon conversion of another offered Security will be listed on The Nasdaq Stock Market LLC, subject to official notice of issuance. We may elect to list any of the other securities on an exchange but are not obligated to do so. It is possible that one or more underwriters may make a market in a series of the Securities, but no underwriter will be obligated to do so and any underwriter may discontinue any market making at any time without notice. We cannot predict the activity of trading in, or liquidity of, our Securities.

The underwriters also may impose a penalty bid. This occurs when a particular underwriter repays to the underwriters a portion of the underwriting discount received by it because the underwriters have repurchased Securities sold by or for the account of that underwriter in stabilizing or short-covering transactions.

These activities by the underwriters may stabilize, maintain or otherwise affect the market price of the Securities. As a result, the price of the Securities may be higher than the price that otherwise might exist in the open market. If these activities are commenced, they may be discontinued by the underwriters at any time. These transactions may be effected on an exchange or automated quotation system, if the Securities are listed on that exchange or admitted for trading on that automated quotation system, in the over-the-counter market or otherwise.

We may from time to time, without the consent of the existing Security holders, create and issue further Securities having the same terms and conditions as the Securities being offered hereby in all respects, except for issue date, issue price and if applicable, the first payment of interest or dividends therein or other terms as noted in the applicable prospectus supplement. Additional Securities issued in this manner will be consolidated with, and will form a single series with, the previously outstanding securities.

Underwriters, dealers and agents that participate in the distribution of the Securities may be underwriters as defined in the Securities Act of 1933, and any discounts or commissions received by them from us and any profit on the resale of the Securities by them may be treated as underwriting discounts and commissions under the Securities Act.

We may have agreements with the underwriters, dealers and agents to indemnify them against certain civil liabilities, including liabilities under the Securities Act of 1933, or to contribute with respect to payments which the underwriters, dealers or agents may be required to make.

Underwriters, dealers and agents may engage in transactions with, or perform services for, us or our subsidiaries or affiliates in the ordinary course of their businesses.

#### LEGAL MATTERS
Ballard Spahr LLP, Philadelphia, Pennsylvania, will render an opinion as to the validity of the Securities for us.

Winston & Strawn LLP, Chicago, Illinois, will render an opinion as to the validity of the Securities for any underwriters, dealers, purchasers or agents. Winston & Strawn LLP provides legal services to Exelon and its subsidiaries from time to time.

#### EXPERTS
The financial statements incorporated in this Prospectus by reference to Exelon Corporation's [Current Report on Form 8-K dated June 30, 2022](https://www.sec.gov/ix?doc=/Archives/edgar/data/8192/000110935722000076/exc-20220630.htm) and management's assessment of the effectiveness of internal

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control over financial reporting (which is included in Management's Report on Internal Control over Financial Reporting) incorporated in this Prospectus by reference to the [Annual Report on Form 10-K of Exelon Corporation for the year ended December 31, 2021](https://www.sec.gov/ix?doc=/Archives/edgar/data/8192/000110935722000039/exc-20211231.htm) have been so incorporated in reliance on the report of PricewaterhouseCoopers LLP, an independent registered public accounting firm, given on the authority of said firm as experts in auditing and accounting.

The financial statements incorporated in this Prospectus by reference to Commonwealth Edison Company, PECO Energy Company's, Baltimore Gas and Electric Company's, Potomac Electric Power Company's, Delmarva Power & Light Company's, and Atlantic City Electric Company's [Current Report on Form 8-K dated June 30, 2022](https://www.sec.gov/ix?doc=/Archives/edgar/data/8192/000110935722000076/exc-20220630.htm) have been so incorporated in reliance on the report of PricewaterhouseCoopers LLP, an independent registered public accounting firm, given on the authority of said firm as experts in auditing and accounting.

#### WHERE YOU CAN FIND MORE INFORMATION
Exelon, ComEd, PECO, BGE, Pepco, DPL and ACE each file reports and other information with the SEC. The public may read and copy any reports or other information that we file with the SEC at the SEC's public reference room, 100 F Street, N.E., Room 1580, Washington, D.C. 20549. The public may obtain information on the operation of the public reference room by calling the SEC at 1-800-SEC-0330. These documents are also available to the public from commercial document retrieval services and at the web site maintained by the SEC at http://www.sec.gov. Reports, proxy statements and other information concerning Exelon may also be inspected at the offices of the New York Stock Exchange, which is located at 20 Broad Street, New York, New York 10005. You may also obtain a copy of the registration statement at no cost by writing us at the following address:

Exelon Corporation

Attn: Investor Relations

10 South Dearborn Street — 54<sup>th</sup> Floor

P.O. Box 805398

Chicago, IL 60680-5398

This prospectus is one part of a registration statement filed on Form S-3 with the SEC under the Securities Act of 1933, as amended, known as the Securities Act. This prospectus does not contain all of the information set forth in the registration statement and the exhibits and schedules to the registration statement. For further information concerning us and the Securities, you should read the entire registration statement, including this prospectus and any related prospectus supplements, and the additional information described under the sub-heading "Documents Incorporated By Reference" below. The registration statement has been filed electronically and may be obtained in any manner listed above. Any statements contained herein concerning the provisions of any document are not necessarily complete, and, in each instance, reference is made to the copy of such document filed as an exhibit to the registration statement or otherwise filed with the SEC. Each such statement is qualified in its entirety by such reference.

Information about us is also available on Exelon's web site at http://www.exeloncorp.com. The information on Exelon's web site is not incorporated into this prospectus by reference, and you should not consider it a part of this prospectus.

#### DOCUMENTS INCORPORATED BY REFERENCE
The SEC allows us to "incorporate by reference" information that we file with the SEC, which means that we can disclose important information to you by referring you to the documents we file with the SEC. The information incorporated by reference is an important part of this prospectus, and information that we file later with the SEC will automatically update and supersede this information. This incorporation by reference does not include documents that are furnished but not filed with the SEC. We incorporate by reference the documents listed below and any future documents that we file with the SEC under Section 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934, as amended (known as the Exchange Act) but prior to the termination of any offering of securities made by this prospectus:

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#### Exelon Corporation (Exchange Act File No. 1-16169)
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • [The description of Exelon's common stock contained in the registration statement on Form 8-A filed under the Securities Exchange Act of 1934 on October 10, 2000, as amended, including any amendment thereto or report filed for the purpose of updating such description;](https://www.sec.gov/Archives/edgar/data/1109357/000095015700000542/0000950157-00-000542-0001.txt)

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • Exelon's [Annual Report on Form 10-K for the year ended December 31, 2021](https://www.sec.gov/ix?doc=/Archives/edgar/data/8192/000110935722000039/exc-20211231.htm) (the financial statements and related audit opinion have been superseded by the financial statements and audit report included in the [Form 8-K filed on June 30, 2022](https://www.sec.gov/ix?doc=/Archives/edgar/data/8192/000110935722000076/exc-20220630.htm));

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • Exelon's [Current Report on Form 8-K filed with the SEC on June 30, 2022](https://www.sec.gov/ix?doc=/Archives/edgar/data/8192/000110935722000076/exc-20220630.htm) (recasting certain portions of the [Annual Report on Form 10-K for the year ended December 31, 2021](https://www.sec.gov/ix?doc=/Archives/edgar/data/8192/000110935722000039/exc-20211231.htm));

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • Exelon's Quarterly Reports on Form 10-Q filed with the SEC on [May 9, 2022](https://www.sec.gov/ix?doc=/Archives/edgar/data/8192/000110935722000059/exc-20220331.htm) and [August 3, 2022;](http://www.sec.gov/Archives/edgar/data/8192/000110935722000092/exc-20220630.htm) and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • Exelon's Current Reports on Form 8-K filed with the SEC on [January 6, 2022](https://www.sec.gov/ix?doc=/Archives/edgar/data/1109357/000110935722000003/exc-20220106.htm), [January 7, 2022](https://www.sec.gov/ix?doc=/Archives/edgar/data/1109357/000110935722000005/exc-20220106.htm), [January 26, 2022](https://www.sec.gov/ix?doc=/Archives/edgar/data/1109357/000110935722000016/exc-20220121.htm), [February 2, 2022](https://www.sec.gov/ix?doc=/Archives/edgar/data/1109357/000110465922010604/tm224978d1_8k.htm), [February 3, 2022](https://www.sec.gov/ix?doc=/Archives/edgar/data/8192/000110465922011422/tm225250d2_8k.htm), [February 10, 2022](https://www.sec.gov/ix?doc=/Archives/edgar/data/1109357/000110935722000021/exc-20220208.htm), [March 7, 2022](https://www.sec.gov/ix?doc=/Archives/edgar/data/1109357/000110935722000044/exc-20220307.htm), [April 1, 2022](https://www.sec.gov/ix?doc=/Archives/edgar/data/1109357/000110465922041453/tm2211134d1_8k.htm), [April 29, 2022.](https://www.sec.gov/ix?doc=/Archives/edgar/data/1109357/000110935722000047/exc-20220426.htm)

#### Commonwealth Edison Company (Exchange Act File No. 1-1839)
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • [ComEd's Annual Report on Form 10-K for the year ended December 31, 2021;](https://www.sec.gov/ix?doc=/Archives/edgar/data/8192/000110935722000039/exc-20211231.htm)

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • ComEd's [Current Report on Form 8-K filed with the SEC on June 30, 2022](https://www.sec.gov/ix?doc=/Archives/edgar/data/8192/000110935722000076/exc-20220630.htm) (recasting certain portions of the [Annual Report on Form 10-K for the year ended December 31, 2021](https://www.sec.gov/ix?doc=/Archives/edgar/data/8192/000110935722000039/exc-20211231.htm));

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • ComEd's Quarterly Reports on Form 10-Q filed with the SEC on [May 9, 2022](https://www.sec.gov/ix?doc=/Archives/edgar/data/8192/000110935722000059/exc-20220331.htm) and [August 3, 2022;](http://www.sec.gov/Archives/edgar/data/8192/000110935722000092/exc-20220630.htm) and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • ComEd's Current Reports on Form 8-K filed with the SEC on [February 3, 2022](https://www.sec.gov/ix?doc=/Archives/edgar/data/8192/000110465922011422/tm225250d2_8k.htm), [February 11, 2022](https://www.sec.gov/ix?doc=/Archives/edgar/data/22606/000002260622000005/exc-20220207.htm), [March 15, 2022](https://www.sec.gov/Archives/edgar/data/22606/000002260622000012/exc-202203158k.htm), [March 16, 2022](https://www.sec.gov/ix?doc=/Archives/edgar/data/22606/000002260622000017/exc-20220315.htm) and [July 1, 2022](https://www.sec.gov/ix?doc=/Archives/edgar/data/22606/000002260622000019/exc-20220701.htm).

#### PECO Energy Company (Exchange Act File No. 000-16844)
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • [PECO's Annual Report on Form 10-K for the year ended December 31, 2021;](https://www.sec.gov/ix?doc=/Archives/edgar/data/8192/000110935722000039/exc-20211231.htm)

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • PECO's [Current Report on Form 8-K filed with the SEC on June 30, 2022](https://www.sec.gov/ix?doc=/Archives/edgar/data/8192/000110935722000076/exc-20220630.htm) (recasting certain portions of the [Annual Report on Form 10-K for the year ended December 31, 2021](https://www.sec.gov/ix?doc=/Archives/edgar/data/8192/000110935722000039/exc-20211231.htm));

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • PECO's Quarterly Reports on Form 10-Q filed with the SEC on [May 9, 2022](https://www.sec.gov/ix?doc=/Archives/edgar/data/8192/000110935722000059/exc-20220331.htm) and [August 3, 2022;](http://www.sec.gov/Archives/edgar/data/8192/000110935722000092/exc-20220630.htm) and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • PECO's Current Reports on Form 8-K filed with the SEC on [February 3, 2022](https://www.sec.gov/ix?doc=/Archives/edgar/data/8192/000110465922011422/tm225250d2_8k.htm) and [May 24, 2022](https://www.sec.gov/ix?doc=/Archives/edgar/data/78100/000007810022000004/exc-20220524.htm).

#### Baltimore Gas and Electric Company (Exchange Act File No. 1-1910)
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • [BGE's Annual Report on Form 10-K for the year ended December 31, 2021;](https://www.sec.gov/ix?doc=/Archives/edgar/data/8192/000110935722000039/exc-20211231.htm)

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • BGE's [Current Report on Form 8-K filed with the SEC on June 30, 2022](https://www.sec.gov/ix?doc=/Archives/edgar/data/8192/000110935722000076/exc-20220630.htm) (recasting certain portions of the [Annual Report on Form 10-K for the year ended December 31, 2021](https://www.sec.gov/ix?doc=/Archives/edgar/data/8192/000110935722000039/exc-20211231.htm));

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • BGE's Quarterly Reports on Form 10-Q filed with the SEC on [May 9, 2022](https://www.sec.gov/ix?doc=/Archives/edgar/data/8192/000110935722000059/exc-20220331.htm) and [August 3, 2022;](http://www.sec.gov/Archives/edgar/data/8192/000110935722000092/exc-20220630.htm) and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • BGE's Current Reports on Form 8-K filed with the SEC on [February 3, 2022](https://www.sec.gov/ix?doc=/Archives/edgar/data/8192/000110465922011422/tm225250d2_8k.htm) and [June 6, 2022](https://www.sec.gov/ix?doc=/Archives/edgar/data/9466/000000946622000003/exc-20220606.htm).

#### Potomac Electric Power Company (Exchange Act File No. 001-01072)
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • [Pepco's Annual Report on Form 10-K for the year ended December 31, 2021;](https://www.sec.gov/ix?doc=/Archives/edgar/data/8192/000110935722000039/exc-20211231.htm)

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • Pepco's [Current Report on Form 8-K filed with the SEC on June 30, 2022](https://www.sec.gov/ix?doc=/Archives/edgar/data/8192/000110935722000076/exc-20220630.htm) (recasting certain portions of the [Annual Report on Form 10-K for the year ended December 31, 2021](https://www.sec.gov/ix?doc=/Archives/edgar/data/8192/000110935722000039/exc-20211231.htm));

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • Pepco's Quarterly Reports on Form 10-Q filed with the SEC on [May 9, 2022](https://www.sec.gov/ix?doc=/Archives/edgar/data/8192/000110935722000059/exc-20220331.htm) and [August 3, 2022;](http://www.sec.gov/Archives/edgar/data/8192/000110935722000092/exc-20220630.htm) and

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&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • Pepco's Current Reports on Form 8-K filed with the SEC on [February 3, 2022](https://www.sec.gov/ix?doc=/Archives/edgar/data/8192/000110465922011422/tm225250d2_8k.htm) and [March 24, 2022](https://www.sec.gov/ix?doc=/Archives/edgar/data/79732/000007973222000004/exc-20220324.htm).

#### Delmarva Power & Light Company (Exchange Act File No. 001-01405)
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • [DPL's Annual Report on Form 10-K for the year ended December 31, 2022;](https://www.sec.gov/ix?doc=/Archives/edgar/data/8192/000110935722000039/exc-20211231.htm)

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • DPL's [Current Report on Form 8-K filed with the SEC on June 30, 2022](https://www.sec.gov/ix?doc=/Archives/edgar/data/8192/000110935722000076/exc-20220630.htm) (recasting certain portions of the [Annual Report on Form 10-K for the year ended December 31, 2021](https://www.sec.gov/ix?doc=/Archives/edgar/data/8192/000110935722000039/exc-20211231.htm));

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • DPL's Quarterly Reports on Form 10-Q filed with the SEC on [May 9, 2022](https://www.sec.gov/ix?doc=/Archives/edgar/data/8192/000110935722000059/exc-20220331.htm) and [August 3, 2022;](http://www.sec.gov/Archives/edgar/data/8192/000110935722000092/exc-20220630.htm) and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • DPL's Current Report on Form 8-K filed with the SEC on [February 3, 2022](https://www.sec.gov/ix?doc=/Archives/edgar/data/8192/000110465922011422/tm225250d2_8k.htm) and [February 15, 2022](https://www.sec.gov/ix?doc=/Archives/edgar/data/8192/000002787922000002/exc-20220215.htm).

#### Atlantic City Electric Company (Exchange Act File No. 001-03559)
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • [ACE's Annual Report on Form 10-K for the year ended December 31, 2021;](https://www.sec.gov/ix?doc=/Archives/edgar/data/8192/000110935722000039/exc-20211231.htm)

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • ACE's [Current Report on Form 8-K filed with the SEC on June 30, 2022](https://www.sec.gov/ix?doc=/Archives/edgar/data/8192/000110935722000076/exc-20220630.htm) (recasting certain portions of the [Annual Report on Form 10-K for the year ended December 31, 2021](https://www.sec.gov/ix?doc=/Archives/edgar/data/8192/000110935722000039/exc-20211231.htm));

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • ACE's Quarterly Reports on Form 10-Q filed with the SEC on [May 9, 2022](https://www.sec.gov/ix?doc=/Archives/edgar/data/8192/000110935722000059/exc-20220331.htm) and [August 3, 2022;](http://www.sec.gov/Archives/edgar/data/8192/000110935722000092/exc-20220630.htm) and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; • ACE's Current Report on Form 8-K filed with the SEC on [February 3, 2022](https://www.sec.gov/ix?doc=/Archives/edgar/data/8192/000110465922011422/tm225250d2_8k.htm) and [February 15, 2022](https://www.sec.gov/ix?doc=/Archives/edgar/data/8192/000002787922000002/exc-20220215.htm).

Upon written or oral request, we will provide without charge to each person, including any beneficial owner, to whom this prospectus is delivered, a copy of any or all of such documents which are incorporated herein by reference (other than exhibits to such documents unless such exhibits are specifically incorporated by reference into the documents that this prospectus incorporates). Written or oral requests for copies should be directed to Exelon Corporation, Attn: Investor Relations, 10 South Dearborn Street, 54<sup>th</sup> Floor, P.O. Box 805398, Chicago, IL 60680-5398, 312-394-2345.

Any statement contained in this prospectus, or in a document all or a portion of which is incorporated by reference, shall be modified or superseded for purposes of this prospectus to the extent that a statement contained in this prospectus, any supplement or any document incorporated by reference modifies or supersedes such statement. Any such statement so modified or superseded shall not, except as so modified or superseded, constitute a part of this prospectus.

All reports and other documents subsequently filed by us pursuant to Sections 13(a), 13(c), 14 and 15(d) of the Exchange Act, prior to the filing of a post-effective amendment, which indicates that all of a class of securities offered hereby have been sold or which deregisters all of a class of securities then remaining unsold, shall be deemed incorporated by reference herein and to be a part hereof from the date of filing of such documents.

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### **TABLE OF CONTENTS** $$% Notes due 20 $% Notes due 20 $% Notes due 20 Exelon Corporation PROSPECTUS SUPPLEMENT Joint Book Runners Barclays Citigroup Goldman Sachs & Co. LLC J.P. Morgan Morgan Stanley MUFG PNC Capital Markets LLC SMBC Nikko Wells Fargo Securities Senior Co- Managers Loop Capital Markets Siebert Williams Shank Huntington Capital Markets , 2023