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As filed with the Securities and Exchange Commission on November 18, 2008

Registration No. 333-145691-02

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Post-Effective Amendment No. 1 to

FORM S-3

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

DELMARVA POWER & LIGHT COMPANY

(Exact Name of Registrant as Specified in Its Charter)

Delaware and Virginia

(State or other jurisdiction of incorporation or organization)

51-0084283

(I.R.S. Employer Identification Number)

800 King Street

P.O. Box 231

Wilmington, Delaware 19899

Telephone: (202) 872-2000

(Address, including zip code, and telephone number, including area code, of registrant’s principal executive offices)

ELLEN SHERIFF ROGERS

Secretary

Delmarva Power & Light Company

800 King Street

P.O. Box 231

Wilmington, Delaware 19899

(202) 872-2000

(Name, address, including zip code, and telephone number, including area code, of agent for service)

Copy to:

D. MICHAEL LEFEVER

Covington & Burling LLP

1201 Pennsylvania Avenue, N.W.

Washington, D.C. 20004

(202) 662-6000

Approximate Date of Commencement of Proposed Sale to the Public: From time to time, as determined by market and other conditions.

If the only securities being registered on this Form are being offered pursuant to dividend or interest reinvestment plans, please check the following box.   ¨

If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, other than securities offered only in connection with dividend or interest reinvestment plans, check the following box.   x

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

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

If this Form is a registration statement pursuant to General Instruction I.D. or a post-effective amendment thereto that shall become effective upon filing with the Commission pursuant to Rule 462(e) under the Securities Act, check the following box.   x

If this Form is a post-effective amendment to a registration statement filed pursuant to General Instruction I.D. filed to register additional securities or additional classes of securities pursuant to Rule 413(b) under the Securities Act, check the following box.   x

In connection with the securities offered hereby, except for the application of these previously-paid fees, DPL will pay “pay-as-you-go registration fees” in accordance with Rule 456(b).

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EXPLANATORY NOTE

On August 24, 2007, Pepco Holdings, Inc., Potomac Electric Power Company, Delmarva Power & Light Company (“DPL”) and Atlantic City Electric Company each filed a combined Registration Statement on Form S-3. This Post-Effective Amendment No. 1 (the “Amendment”) is an amendment to the Registration Statement on Form S-3 (File No. 333-145691-02) filed by DPL on such date (the “DPL Registration Statement”) and is being filed by DPL for the purpose of (a) registering pursuant to Rule 413(b) under Securities Act of 1933, as amended (the “Securities Act”), first mortgage bonds as an additional class of DPL securities that may be offered and sold pursuant to the DPL Registration Statement, (b) adding disclosure to the DPL base prospectus included in the DPL Registration Statement describing the first mortgage bonds, (c) updating certain information relating to DPL contained in the DPL base prospectus, and (d) filing additional exhibits to the DPL Registration Statement relating to the first mortgage bonds. In accordance with Rule 462(e) under the Securities Act, this Amendment shall become effective immediately upon filing with the Securities and Exchange Commission.

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PROSPECTUS

Delmarva Power & Light Company

Debt Securities

This prospectus relates to debt securities that we may offer from time to time. The securities may be offered in one or more series and in an amount or number, at prices and on other terms and conditions to be determined at the time of sale and described in a prospectus supplement accompanying this prospectus. This prospectus may not be used to sell securities unless accompanied by a prospectus supplement.

We may offer and sell the securities on a continuous or delayed basis to or through one or more underwriters, dealers or agents, or directly to the purchasers.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or passed upon the adequacy or accuracy of this prospectus. Any representation to the contrary is a criminal offense.

The date of this prospectus is November 18, 2008.

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This prospectus is a part of a registration statement we filed with the Securities and Exchange Commission, or SEC. You should rely only on the information we have provided or incorporated by reference in this prospectus and the accompanying prospectus supplement. We have not authorized anyone to provide you with additional or different information. We are not making an offer of these securities in any jurisdiction where the offer is not permitted. You should assume that the information in this prospectus or the accompanying prospectus supplement is accurate only as of the date on the front of that document and that any information contained in a document incorporated by reference is accurate only as of the date of that incorporated document.

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ABOUT THIS PROSPECTUS

This prospectus is a part of a registration statement that we filed with the SEC utilizing an automatic shelf registration process. We may use this prospectus to offer and sell from time to time any one or a combination of the securities described in this prospectus in one or more offerings. This prospectus provides you with a general description of the securities we may offer. Each time we sell securities, we will describe in an accompanying prospectus supplement the type, amount or number and other terms and conditions of the securities being offered, the price at which the securities are being offered, and the plan of distribution for the securities. The specific terms of the offered securities may vary from the general terms of the securities described in this prospectus, and accordingly the description of the securities contained in this prospectus is subject to, and qualified by reference to, the specific terms of the offered securities contained in the accompanied prospectus supplement. The prospectus supplement may also add, update or change information contained in this prospectus, including information about us, contained in this prospectus. Therefore, for a complete understanding of the offered securities, you should read both this prospectus and any prospectus supplement together with additional information described under the heading “Where You Can Find More Information.”

For more detailed information about the securities, you can also read the exhibits to the registration statement. Those exhibits may be filed with the registration statement or may be incorporated by reference to earlier SEC filings listed in the registration statement or subsequent filings that we may make under the Securities Exchange Act of 1934, as amended (the “Securities Exchange Act”).

In this prospectus, unless the context indicates otherwise, the words “DPL,” “the company,” “we,” “our,” “ours” and “us” refer to Delmarva Power & Light Company and its consolidated subsidiaries.

NOTE REGARDING FORWARD-LOOKING STATEMENTS

Some of the statements contained in this prospectus, the accompanying prospectus supplement and incorporated by reference into this prospectus are forward-looking statements within the meaning of Section 27A of the Securities Act and Section 21E of the Securities Exchange Act, and are subject to the safe harbor created by the Private Securities Litigation Reform Act of 1995. Forward-looking statements are those that describe or predict future events or trends and include declarations regarding our intentions, beliefs and expectations. In some cases, you can identify forward-looking statements by terminology such as “may,” “will,” “should,” “expects,” “plans,” “anticipates,” “believes,” “estimates,” “predicts,” “potential” or “continue” or the negative of such terms or other comparable terminology. Forward-looking statements are not guarantees of future performance, and actual results could differ materially from those indicated by the forward-looking statements. Forward-looking statements involve estimates, assumptions, known and unknown risks, uncertainties and other factors that may cause our or our industry’s actual results, levels of activity, performance or achievements to be materially different from any future results, levels of activity, performance or achievements expressed or implied by such forward-looking statements.

The forward-looking statements contained or incorporated by reference herein and in the accompanying prospectus supplement are qualified in their entirety by reference to the following important factors, which are difficult to predict, contain uncertainties, are beyond our control and may cause actual results to differ materially from those contained in forward-looking statements:

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Any forward-looking statements speak only as of the date of this prospectus or any prospectus supplement, and we undertake no obligation to update any forward-looking statements to reflect events or circumstances after the date on which such statements are made or to reflect the occurrence of unanticipated events. New factors emerge from time to time, and it is not possible for us to predict all of such factors, nor can we assess the impact of any such factor on our business or the extent to which any factor, or combination of factors, may cause results to differ materially from those contained in any forward-looking statements. The foregoing review of factors should not be construed as exhaustive.

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DELMARVA POWER & LIGHT COMPANY

We are a regulated public utility company engaged in the transmission and distribution of electricity in Delaware and portions of Maryland and provide natural gas supply and distribution service in northern Delaware. We are a wholly owned subsidiary of Pepco Holdings, Inc.

Our electricity distribution territories encompass Kent, New Castle and Sussex counties in Delaware and Caroline, Cecil, Dorchester, Harford, Kent, Queen Anne’s, Somerset, Talbot, Wicomico and Worchester counties in Maryland. In January 2008, we sold our distribution service territory and substantially all of our transmissions assets in Virginia.

We are responsible for the delivery of electricity in our electricity service territory, which covers approximately 5,000 square miles and, as of December 31, 2007, had a population of approximately 1.3 million. As of December 31, 2007, we delivered electricity to 519,000 customers, of which 298,000 were located in Delaware, 198,000 were located in Maryland and 23,000 were located in Virginia. Of the 13,680,000 megawatt hours of electricity we delivered in 2007, 39% was delivered to residential customers, 40% was delivered to commercial customers and 21% was delivered to industrial customers. The rates we are paid for the delivery of electricity are established in Delaware by the Delaware Public Service Commission and in Maryland by the Maryland Public Service Commission.

Our transmission facilities are interconnected with the transmission facilities of contiguous facilities and as such are part of an interstate power transmission grid over which electricity is transmitted throughout the eastern United States. We are members of the PJM Regional Transmission Organization, which directs the operation of our transmission facilities. The rates we are paid for the transmission of electricity over our facilities are established by the Federal Energy Regulatory Commission.

We also supply electricity at regulated rates to retail customers in our service territory who do not elect to purchase electricity from a competitive energy supplier, which is referred to as standard offer service, or SOS. We purchase the power supply required to satisfy our SOS obligations from wholesale suppliers under contracts entered into pursuant to a competitive bid procedure approved by the applicable public service commission.

Our natural gas service territory encompasses New Castle County in Delaware and covers approximately 275 square miles, with a population of approximately 500,000. As of December 31, 2007, we delivered natural gas to 122,000 customers. In 2007, we delivered 20,700,000 Mcf (one thousand cubic feet) of natural gas to customers in our Delaware service territory, of which approximately 38% were sales to residential customers, 25% were sales to commercial customers, 4% were sales to industrial customers, and 33% were sales to customers receiving a transportation-only service. Large and medium volume commercial and industrial natural gas customers may purchase natural gas either from us or from other suppliers. We purchase natural gas supplies for resale to our sales service customers from marketers and producers through a combination of long-term agreements and next-day delivery arrangements.

Our headquarters are located at 800 King Street, P.O. Box 231, Wilmington, DE 19899, and our telephone number is (202) 872-2000.

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USE OF PROCEEDS

We intend to use the net proceeds from the sale of the securities offered by this prospectus as described in the accompanying prospectus supplement.

For purposes of calculating the ratio of earnings to fixed charges, earnings consist of net income, plus taxes based on income, plus fixed charges, which consist of interest expense (which includes distributions on Company Obligated Mandatorily Redeemable Preferred Securities of Subsidiary Trust (the “Trust Preferred”) subsequent to the implementation of Statement of Financial Accounting Standards No. 150 on July 1, 2003), interest factor in rentals and, prior to the implementation of SFAS 150, distributions on the Trust Preferred. We redeemed the Trust Preferred in May 2004.

DESCRIPTION OF DEBT SECURITIES

The following is a general description of the debt securities that we may offer pursuant to this prospectus. The debt securities may be either first mortgage bonds or other debt securities (collectively, “debt securities”). The specific terms of the debt securities and the extent, if any, to which the following general provisions will not apply to such debt securities, will be described in an accompanying prospectus supplement relating to a particular offering of debt securities. We may also sell hybrid securities that combine certain features of debt securities described in this prospectus.

We may issue:

The statements set forth below are summaries of the material terms of the mortgage and the note indenture. In addition to this summary, you are urged to review the mortgage and the note indenture, which are incorporated by reference as exhibits to the registration statement of which this prospectus is a part.

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D ESCRIPTION OF F IRST M ORTGAGE B ONDS

The following description of the first mortgage bonds sets forth certain general terms and provisions of the first mortgage bonds that we may offer pursuant to this prospectus, which we refer to as new bonds. The form of supplemental indenture to be used in connection with each issuance of new bonds is filed as an exhibit to the registration statement.

As of September 30, 2008, we had $80.5 million of first mortgage bonds outstanding, all of which have been issued as collateral bonds to secure certain series of our outstanding variable rate demand bonds.

General

The prospectus supplement relating to a particular offering of new bonds will describe the terms of the new bonds, including:

The mortgage does not contain any covenants or other provisions that specifically are intended to afford holders of the new bonds special protection in the event of a highly leveraged transaction.

Payment of Principal and Interest

We will pay principal, premium, if any, and interest on the new bonds in immediately available funds at the corporate trust office of The Bank of New York Mellon or at the office of any other paying agent that we may designate. (Mortgage, Section 5.03)

Registration and Transfer

We will issue the new bonds only in fully registered form without coupons. Unless the prospectus supplement states otherwise, we will issue the new bonds in denominations of $1,000 or any integral multiple thereof. We may issue the new bonds of any series in the form book-entry securities which will be deposited with, or on behalf of, a depositary identified in the prospectus supplement relating to such series and registered in the name of the depositary or its nominee as more fully described below under the heading “Book-Entry Debt Securities.”

So long as any first mortgage bonds are outstanding, we must maintain an office or agency where holders can present or surrender first mortgage bonds for payment or for transfer or exchange and where holders can serve notices and demands to or upon us. (Mortgage Sections 2.03 and 5.03) We have designated the corporate trust office of The Bank of New York Mellon in the City of New York as our agent for these purposes. We will not impose charges on any transfer or exchange, other than as may be required for the payment of any taxes or other governmental charges incident thereto. (Mortgage, Section 2.03)

No Sinking Fund

Unless the relevant prospectus supplement states otherwise, there will be no improvement or sinking fund for the new bonds.

Maintenance Fund

If the cumulative amount we have expended for property additions subsequent to October 15, 1943, does not at the end of each calendar year equal or exceed the minimum provision for property retirements or depreciation for the same period (calculated as specified in the mortgage), we are required to deposit with the mortgage

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trustee cash in an amount equal to the deficiency on or before the next succeeding April 30. As an alternative to the deposit of cash, we may instead elect to reduce by an equal amount the principal balance of retired first mortgage bonds that have not previously been used as the basis for issuing first mortgage bonds, the withdrawal of cash or as a credit under the mortgage. (Mortgage, Section 5.08)

For the year ended December 31, 2007, our cumulative property additions exceeded the minimum required provision for property retirements or depreciation and, therefore, we were not required to deposit cash or use any retired first mortgage bonds to satisfy the maintenance fund requirement.

Security

The new bonds will be secured equally with all other first mortgage bonds outstanding or hereinafter issued under the mortgage (except as any sinking fund may afford additional security for a particular series) by the lien of the mortgage which constitutes a first lien on substantially all of our properties and franchises, other than the following:

provided, that if there is a completed default under the mortgage and the mortgage trustee or a receiver takes possession of the mortgaged property as provided under the mortgage, the property described in clauses (iii) and (iv) will cease to be excepted from the lien of the mortgage to the extent permitted by law.

The lien of the mortgage is subject to (a) the conditions and limitations in the instruments through which we claim title to our properties, (b) excepted encumbrances (as defined in the mortgage), and (c) the prior lien of the mortgage trustee for its reasonable compensation, expenses and liability. The lien of the mortgage is subject further to the qualification that where payments for rights-of-way on or under private property for transmission and distribution lines and mains were minor in amount, no examination of underlying titles as to rights-of-way have been made.

The lien of the mortgage also extends to after-acquired property (other than the excluded property described above), including property acquired as a result of a merger or consolidation. However, the after-acquired property may be subject to prior liens and to possible rights of others that may attach prior to recordation of a supplemental indenture describing such property after its acquisition.

Issuance of Additional First Mortgage Bonds

Subject to the limitations described in the following paragraph, we may issue additional first mortgage bonds ranking equally with the new bonds in an aggregate amount of up to:

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(Mortgage, Article IV)

Property additions include property that is used or useful for the business of generating, manufacturing, purchasing or otherwise acquiring, transmitting, distributing or supplying electricity or gas or steam or hot water for power or heat or other purposes. To qualify as a property additions, the property must be located in the States of Delaware, Maryland, Virginia or states contiguous thereto. (Mortgage, Section 1.03).

We cannot issue additional first mortgage bonds unless our “net earnings” (as defined by the mortgage) for any 12 consecutive calendar months during the immediately preceding 15 calendar months have been at least two times the annual interest requirement on the new bonds to be issued and all other first mortgage bonds and prior lien bonds then outstanding. This limitation does not apply if the first mortgage bonds are being issued on the basis of refundable prior lien bonds or retired bonds unless the refundable prior lien bonds or retired bonds bear an equal or lower interest rate than that of the new bonds and the maturity date of the refundable prior lien bonds or retired bonds is less than two years after the maturity date of the new bonds.

(Mortgage, Sections 1.06 and 4.08)

Release of Property

Generally, as long as we are not in default in the payment of interest on any outstanding first mortgage bonds and no completed defaults have occurred and are continuing under the mortgage, we may obtain the release of property from the lien of the mortgage by reducing the amount of bondable property additions or retired bonds that otherwise could be the basis for issuing new bonds under the mortgage. We also may obtain the release of property from the lien of the mortgage by depositing with the mortgage trustee (i) cash, (ii) purchase money obligations that we receive as consideration for and secured by the property to be released or (iii) the fair value of any property additions that we acquire as consideration for the property to be released in an amount at least equal to the fair value of the property to be released. Purchase money obligations may only be used as the basis for releasing property under the mortgage to the extent that (i) the principal amount thereof does not exceed 60% of the fair value of the bondable property to be released and (ii) the aggregate amount of such purchase money obligations, when combined with all other purchase money obligations used as the basis for releasing property, does not exceed 20% of the sum of all outstanding first mortgage bonds plus all new bonds that could be issued on the basis of property additions, refundable prior lien bonds and retired bonds under the mortgage. (Mortgage, Section 9.03)

As long as we are not in default in the payment of interest on any outstanding first mortgage bonds and no completed defaults have occurred and are continuing under the mortgage, we may, without release by the mortgage trustee, (i) dispose of any obsolete property upon replacing such property with other property of at least equal value or (ii) surrender or modify any right, power, franchise, license or permit as our board of directors determines is desirable in the conduct of our business and does not impair the security for the then outstanding first mortgage bonds. (Mortgage, Section 9.02)

Withdrawal of Cash Deposited with Mortgage Trustee

As long as we are not in default in the payment of interest on any outstanding first mortgage bonds and no completed defaults have occurred and are continuing under the mortgage, we may withdraw cash deposited with the mortgage trustee to obtain the release of property or for other purposes:

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(Mortgage, Section 9.06).

Cash may also be used by the mortgage trustee, at our discretion, to redeem or purchase outstanding first mortgage bonds at a purchase price not exceeding the current redemption price of the first mortgage bonds or, if the first mortgage bonds are not redeemable prior to maturity at a price of not more than 105% of the principal amount Any cash that is not withdrawn, used or applied within the three year period after it is deposited with the mortgage trustee, must be used by the mortgage trustee to redeem or repurchase outstanding first mortgage bonds. (Mortgage Sections 8.06 and 9.06)

Dividend Restrictions on Common Stock

The mortgage prohibits us from declaring or paying any dividend or making distributions to our common stockholders (other than dividends or distributions solely in shares of common stock) or purchasing or otherwise acquiring our common stock for value, unless after the payment of such dividend or the making of such distribution, purchase or acquisition, the provision for property retirements or depreciation made during the period from October 15, 1943 to the end of the calendar year preceding the date of such payment distribution, purchase or acquisition, plus our earned surplus accumulated on and after October 15, 1943 is not less than the aggregate minimum provision for property retirements or depreciation for the period from October 15, 1943 to the end of the calendar year preceding the date of such payment distribution, purchase or acquisition (calculated as specified in the mortgage). There was no such deficiency as of December 31, 2007. (Mortgage Section 5.25)

Consolidation, Merger or Transfer of Assets

Nothing in the mortgage or terms of the first mortgage bonds prevents us from:

provided that:

(Mortgage, Sections 13.01 and 13.02).

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If we consolidate with or merge into any other corporation, or convey or transfer our property as an entirety or substantially as an entirety, the mortgage will not (unless the successor corporation elects otherwise) be or become a lien upon any of the properties or franchises owned by the successor corporation, except for:

(Mortgage, Section 13.03)

Although there is a limited body of case law interpreting the phrases “substantially all” and “substantially as an entirety,” there is no precise established definition of these phrases under applicable law. As a result of this uncertainty:

Modification

Modifications Without Consent

Without the consent of the holders of first mortgage bonds, we and the mortgage trustee may enter into one or more supplemental indentures for any of the following purposes:

(Mortgage, Section 17.01)

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Modifications With Consent

The mortgage may be modified with our consent and the consent of the holders of 75% of the aggregate principal amount of the first mortgage bonds then outstanding that are affected by such modification; provided, however, that no such modification shall (i) extend the maturity of, reduce the rate or extend the time of payment of interest on, or reduce the principal amount of any first mortgage bonds without the consent of the holder of each first mortgage bond so affected or (ii) reduce the consent percentage required for modification without the consent of the holders of all of the outstanding first mortgage bonds. (Mortgage, Section 17.02)

The mortgage provides that any first mortgage bonds owned by us, any other obligor on the first mortgage bonds or any of our or their affiliates, shall be disregarded and considered not to be outstanding in determining whether the required holders have given a request or consent. (Mortgage, Section 11.03)

Completed Defaults

The term “completed default,” when used in the mortgage with respect to all first mortgage bonds issued thereunder, means any of the following:

The mortgage requires the mortgage trustee to provide notice to the holders of the first mortgage bonds within 60 days after the occurrence of a completed default described in clause (vi) and within 90 days after the occurrence of all other completed defaults (not including any specified grace periods) known to the mortgage trustee, unless such default was cured prior to the giving of the notice. The mortgage trustee may, however, except in the case of a default in the payment of principal, any premium, or interest, or in the payment of any sinking or purchase fund installment, withhold notice to the holders of the first mortgage bonds of any default if the mortgage trustee in good faith determines that the withholding of notice is in the interests of the holders. (Mortgage, Sections 10.01 and 10.02)

Remedies

If a completed default exists, the mortgage trustee in its discretion, or the holders of at least 25% in principal amount of all outstanding first mortgage bonds upon written notice to us and the mortgage trustee, may declare all outstanding first mortgage bonds immediately due and payable. If, before any judgment or decree for the payment of monies due is obtained or any sale of mortgaged property has occurred, all interest in arrears has been paid and all defaults have been cured, the holders of a majority in principal amount of outstanding first mortgage bonds may waive all defaults and rescind and annul such declaration and its consequences. (Mortgage, Section 10.01)

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In circumstances other than as described in the preceding paragraph, the holders of at least two-thirds in aggregate principal amount of first mortgage bonds outstanding may on behalf of all holders of first mortgage bonds waive any past completed default except a completed default relating to the non-payment of any principal or interest thereon. (Mortgage, Section 10.06)

Holders of not less than a majority of the aggregate principal amount of the first mortgage bonds then outstanding may in writing require the mortgage trustee to take such action to enforce payment of the first mortgage bonds then outstanding and to foreclose the mortgage and sell the property when such actions are permitted by the mortgage. The mortgage trustee is not obligated to take such action unless the mortgage trustee has been reasonably indemnified. (Mortgage, Sections 10.05)

No holder of a first mortgage bond has the right to institute proceedings for the enforcement of the mortgage, unless:

However, this provision does not impair the right of any holder of a first mortgage bond to enforce our obligation to pay the principal of an interest on such first mortgage bond when due, which obligations are absolute and unconditional. (Mortgage, Section 10.16)

The laws of the jurisdictions in which the mortgaged property is located may limit or deny the ability of the mortgage trustee or the bondholders to enforce certain rights and remedies provided in the mortgage in accordance with their terms.

We will provide to the mortgage trustee an annual statement by an appropriate officer as to our compliance with all conditions and covenants under the mortgage. (Mortgage, Section 6.03(2)).

Defeasance and Discharge

If at any time we:

then such first mortgage bonds will be deemed paid for purposes of the mortgage and shall not be entitled to any lien or benefit under the mortgage. (Mortgage, Sections 8.04 and 15.01)

If all of the first mortgage bonds, including all interest due thereon, have been paid or deemed paid, and we have observed all of our covenants under the mortgage, the mortgage trustee is obligated, upon our request, to cancel and discharge the lien of the mortgage and to reconvey and transfer to us the mortgaged property. (Mortgage, Section 15.01)

Title

We, the mortgage trustee and any paying agent may deem and treat the person in whose name first mortgage bonds are registered as the absolute owner thereof for the purpose of making payments and for all other purposes of the mortgage. (Mortgage, Section 11.02)

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Resignation or Removal of Mortgage Trustee

The mortgage trustee may resign at anytime by giving written notice to us specifying the day upon which the resignation will take effect and by publishing such notice in a daily newspaper of general circulation in the City of New York on any business day of a week for three successive calendar weeks. If the mortgage trustee has or acquires any conflicting interest as defined in Section 310(b) of the Trust Indenture Act of 1939, as amended (the “Trust Indenture Act”), the mortgage trustee generally must either eliminate the conflicting interest or resign within 90 days. The mortgage trustee may be removed at anytime by the holders of a majority in principal amount of first mortgage bonds then outstanding. No resignation or removal of a mortgage trustee and no appointment of a successor trustee will be effective until the acceptance of appointment by a successor mortgage trustee. (Mortgage, Article XIV).

Information About the Mortgage Trustee

The Bank of New York Mellon acts as trustee under the mortgage. In addition, The Bank of New York Mellon and its affiliates act, and may act, as trustee and paying agent under various other indentures, trusts and guarantees of us and our affiliates. We and our affiliates maintain deposit accounts and credit and liquidity facilities and conduct other banking transactions with The Bank of New York Mellon and its affiliates in the ordinary course of our business.

D ESCRIPTION OF O THER D EBT S ECURITIES

The following description sets forth certain general terms and provisions of the other debt securities that we may offer pursuant to this prospectus.

General

Unless the relevant prospectus supplement indicates otherwise, the other debt securities will mature on any day from nine months to 40 years from the original issue date. Each other debt security will bear interest at either fixed rates or floating rates. The relevant prospectus supplement, or the pricing supplement described in the prospectus supplement, will set forth the following terms of the other debt securities:

The note indenture does not contain any covenants or other provisions that specifically are intended to afford holders of the other debt securities special protection in the event of a highly leveraged transaction.

No Sinking Fund

The other debt securities will not be subject to any sinking fund.

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Unsecured Obligations

The other debt securities will be unsecured and will rank pari passu with all of our other unsecured and unsubordinated indebtedness. As of September 30, 2008, we had $340 million in aggregate principal amount of other debt securities outstanding under the note indenture. The note indenture does not restrict us from incurring more secured debt.

Registration and Transfer

The other debt securities will be issued only in fully registered certificated or book-entry form, as described below under “Book Entry Notes,” without coupons and, except as may otherwise be provided in the applicable prospectus supplement or pricing supplement, in denominations of $1,000 or any multiple thereof. We may issue other debt securities of any series in the form book-entry securities which will be deposited with, or on behalf of, a depositary identified in the prospectus supplement relating to such series and registered in the name of the depositary or its nominee as more fully described below under the heading “Book-Entry Debt Securities.”

If the other debt securities are issued in certificated form, the transfer of the other debt securities may be registered, and the other debt securities may be exchanged for different debt securities of the same series, of authorized denominations and with the same terms and aggregate principal amount, at the offices of the note trustee. We may change the place for registration of transfer and exchange of the other debt securities and designate additional places for registration of transfer and exchange. (Note Indenture, Sections 305 and 602)

No service charge will be made for any transfer or exchange of the other debt securities. However, we may require payment to cover any tax or other governmental charge that may be imposed in connection with any transfer or exchange. We will not be required to register the transfer of, or to exchange, the other debt securities of any series during the 15 days prior to the date of mailing notice of redemption of any other debt securities of that series or any debt security that is selected for redemption. (Note Indenture, Section 305)

Payment and Paying Agents

Unless the relevant prospectus supplement indicates otherwise, payment of interest on an other debt security on any interest payment date will be made to the person in whose name such other debt security is registered at the close of business on the regular record date for such interest payment. If there has been a default in the payment of interest on any other debt security, the defaulted interest may be paid to the holder of such other debt security as of the close of business on a special record date selected by the note trustee that is (a) no less than 10 nor more than 15 days before the date established by us for the proposed payment of such defaulted interest and no less than 10 days after we provide the note trustee with notice of the proposed payment or (b) in any other manner permitted by any securities exchange on which the other debt security may be listed, if the note trustee finds it practicable. (Note Indenture, Section 307)

Unless the relevant prospectus supplement indicates otherwise, principal of, premium, if any, and any interest on the other debt securities will be payable at the office of the paying agent designated by us. Unless otherwise indicated in the relevant prospectus supplement, the corporate trust office of the note trustee in the Borough of Manhattan, City of New York will be designated as our sole paying agent for payments with respect to the other debt securities of each series. Any other paying agents initially designated by us for the other debt securities of a particular series will be named in the relevant prospectus supplement. We may at any time designate additional paying agents or rescind the designation of any paying agent or approve a change in the office through which any paying agent acts, except that we will be required to maintain a paying agent in each place of payment for the other debt securities of a particular series. (Note Indenture, Section 602)

All moneys paid by us to a paying agent for the payment of the principal of, premium, if any, or any interest on any other debt security which remain unclaimed for two years after such principal, premium or interest has become due and payable will be repaid to us, and the holder of such other debt security thereafter may look only to us for payment. (Note Indenture, Section 603)

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Defeasance and Discharge

The note indenture provides that we will be deemed to have paid, and our entire indebtedness will be deemed to have been satisfied and discharged with respect to, any other debt security or any portion of the principal amount thereof prior to maturity if:

which will be sufficient to pay when due the principal of, any premium and interest on such other debt securities or portions thereof; and

(Note Indenture, Section 701)

Consolidation, Merger and Sale of Assets

The note indenture provides that we may not consolidate with or merge into any other corporation or convey, transfer or lease our properties and assets substantially as an entirety to any entity, unless:

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(Note Indenture, Section 1101)

Upon any consolidation or merger, or any conveyance, transfer or lease of our properties and assets substantially as an entirety to any other entity as described above, the successor corporation or the entity to which such conveyance, transfer or lease is made will succeed to, and be substituted for, us under the note indenture, and may exercise every right and power of ours under the note indenture, and, except in the case of a lease, we will be relieved of all obligations and covenants under the note indenture and the outstanding other debt securities. (Note Indenture, Section 1102)

Although there is a limited body of case law interpreting the phrase “substantially as an entirety,” there is no precise established definition of the phrase under applicable law. As a result of this uncertainty:

Event of Default

The term “Event of Default,” when used in the note indenture with respect to any series of other debt securities issued thereunder, means any of the following:

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(Note Indenture, Section 801)

An Event of Default for a particular series of other debt securities does not necessarily constitute an Event of Default for any other series of other debt securities issued under the note indenture. The note trustee is required to give the holders of other debt securities written notice of any default known to the note trustee within 90 days after the occurrence unless such default is cured and waived. The note trustee may withhold notice to the holders of other debt securities of any default, except default in the payment of principal, any premium, or interest, if the note trustee in good faith determines the withholding of notice to be in the interests of the holders. In the case of a default under clause (iii) above, no notice to the holders of the affected other debt securities may be given until at least 30 days after the occurrence of the default. (Note Indenture, Sections 802 and 902)

Remedies

If an Event of Default under the note indenture with respect to any series of other debt securities occurs and continues, the note trustee or the holders of at least 33% in aggregate principal amount of all the other debt securities of the series may declare the principal amount of all the other debt securities of that series to be due and payable immediately. If an Event of Default under the note indenture with respect to more than one series of other debt securities occurs and continues, the note trustee or the holders of at least 33% in aggregate principal amount of all series in respect of which an Event of Default under the note indenture shall have occurred and be continuing, considered as one class, may declare the payment of the principal amount of all the other debt securities of the affected series to be immediately due and payable. (Note Indenture, Section 802)

There is no automatic acceleration, even in the event of our bankruptcy, insolvency or reorganization. (Note Indenture, Section 802)

At any time after a declaration of acceleration with respect to the other debt securities of any series has been made and before a judgment or decree for payment of the money due has been obtained, the holders of a majority in principal amount of the outstanding other debt securities of such series may rescind and annul the declaration and its consequences if:

(Note Indenture, Section 802)

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The holders of not less than a majority in principal amount of the outstanding other debt securities of any series may on behalf of the holders of all other debt securities of such series, waive any past default under the note indenture with respect to that series and its consequences, except a default in the payment of principal, premium, if any, or interest and certain covenants and provisions of the note indenture that cannot be modified or be amended without the consent of the holder of each outstanding debt security of the series affected (see “Modification and Waiver” below). (Note Indenture, Section 813)

The note trustee is not obligated to exercise any of its rights or powers under the note indenture at the request or direction of any of the holders, unless the holders offer the note trustee reasonable security or indemnity. (Note Indenture, Section 903) If they provide this reasonable indemnity, the holders of a majority in principal amount of any series of other debt securities, and if more than one series is affected, the holders of a majority in principal amount of all affected series, considered as one class, will have the right to direct the time, method and place of conducting any proceeding for any remedy available to the note trustee or exercising any trust or power conferred upon the note trustee. The note trustee is not obligated to comply with directions that conflict with law or other provisions of the note indenture or that would involve the note trustee in personal liability in circumstances where the indemnity would not, in the note trustee’s sole discretion, be adequate. The note trustee may take any other action that it deems proper and is not inconsistent with such direction. (Note Indenture, Section 812)

No holder of other debt securities of any series will have any right to institute any proceeding under the note indenture, for the appointment of a receiver or trustee, or for any remedy under the note indenture, unless:

In addition, no holder of other debt securities has any right under the note indenture to affect, disturb or prejudice the rights of any other holder of other debt securities or to obtain or seek to obtain priority or preference over any other holders. However, these limitations do not apply to a suit by a holder of a debt security to enforce payment of the principal, premium, if any, or interest on the debt security on or after the applicable due date. (Note Indenture, Sections 807 and 808)

We will provide to the note trustee an annual statement by an appropriate officer as to our compliance with all obligations under the note indenture. (Note Indenture, Section 608)

Modification and Waiver

Without the consent of any holder of other debt securities, we and the note trustee may enter into one or more supplemental indentures for any of the following purposes:

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(Note Indenture, Section 1201)

The consent of the holders of at least a majority in aggregate principal amount of the other debt securities of all series, or all tranches of a series, affected by a modification to the note indenture, considered as one class, is required for all other modifications to the note indenture. However, no such amendment or modification may, without the consent of the holder of each outstanding debt security affected thereby:

(Note Indenture, Section 1202)

A supplemental indenture which changes or eliminates any covenant or other provision of the note indenture that was expressly included solely for the benefit of one or more particular series of other debt securities or

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tranches, or modifies the rights of the holders of other debt securities of such series or tranches with respect to such covenant or other provision, will not affect the rights under the note indenture of the holders of the other debt securities of any other series or tranches. (Note Indenture, Section 1202)

If any provision of the note indenture limits, qualifies or conflicts with another provision of the note indenture that is required by the Trust Indenture Act to be included in the note indenture, the required provision will control. (Note Indenture, Section 108)

The note indenture provides that other debt securities owned by us, or any other obligor upon the other debt securities, or any of our or their affiliates, shall be disregarded and considered not to be outstanding in determining whether the required holders have given a request, demand, authorization, direction, notice, waiver or consent. (Note Indenture, Section 101)

We may fix in advance a record date to determine the required number of holders entitled to give any request, demand, authorization, direction, notice, consent, waiver or other such act of the holders, but we shall have no obligation to do so. If we fix a record date, the request, demand, authorization, direction, notice, consent, waiver or other act of the holders may be given before or after that record date, but only the holders of record at the close of business on that record date will be considered holders for the purposes of determining whether holders of the required percentage of the outstanding other debt securities have authorized or agreed or consented to the request, demand, authorization, direction, notice, consent, waiver or other act of the holders. For that purpose, the outstanding other debt securities shall be computed as of the record date. Any request, demand, authorization, direction, notice, consent, election, waiver or other act of a holder will bind every future holder of the same other debt security and the holder of every other debt security issued upon the registration of, transfer of, in exchange for or in lieu of that other debt security in respect of anything done, omitted or suffered to be done by the note trustee or us in reliance thereon, whether or not notation of that action is made upon the other debt security. (Note Indenture, Section 104)

Removal or Resignation of the Note Trustee

The note trustee may resign at any time with respect to any series of other debt securities by giving written notice to us. If the note trustee has or acquires any conflicting interest as defined in Section 310(b) of the Trust Indenture Act, within 90 days the note trustee generally must either eliminate the conflicting interest or resign. The holders of a majority in principal amount of any series of other debt securities may remove the note trustee with respect to the other debt securities of that series at any time by giving written notice to us and the note trustee. No resignation or removal of a note trustee and no appointment of a successor note trustee will be effective until the acceptance of appointment by a successor note trustee. If at any time:

then we may remove the note trustee with respect to all of the other debt securities or any such bona fide holder may, in accordance with the note indenture, petition a court to remove the note trustee with respect to all of the other debt securities and appoint a successor note trustee.

(Note Indenture, Sections 908 and 910)

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Notices

Notices to holders of other debt securities will be given by mail to the addresses of such holders as they may appear in the security register for the other debt securities. (Note Indenture, Section 106)

Title

We, the note trustee and any agent of us or the note trustee may treat the person in whose name other debt securities are registered as the absolute owner thereof, whether or not the other debt securities may be overdue, for the purpose of making payments and for all other purposes irrespective of notice to the contrary. (Note Indenture, Section 308)

Governing Law

The note indenture and the other debt securities are governed by, and construed in accordance with, the laws of the State of New York. (Note Indenture, Section 113)

Information About the Note Trustee

The Bank of New York Mellon Trust Company, N.A. acts as trustee under the note indenture. In addition, The Bank of New York Mellon Trust Company, N.A. and its affiliates act, and may act, as trustee and paying agent under various other indentures, trusts and guarantees of us and our affiliates. We and our affiliates maintain deposit accounts and credit and liquidity facilities and conduct other banking transactions with The Bank of New York Mellon Trust Company, N.A. and its affiliates in the ordinary course of our business.

B OOK -E NTRY D EBT S ECURITIES

We may issue both first mortgage bonds and other debt securities of any series in the form of one or more fully-registered debt securities (which we refer to as a book-entry note) which will be deposited with, or on behalf of, a depositary identified in the prospectus supplement relating to such series and registered in the name of the depositary or its nominee. Except as set forth below, the book-entry note may not be transferred except as a whole:

Depositary Arrangements

We will describe the specific terms of the depositary arrangement with respect to any portion of a series of debt securities to be represented by a book-entry note in the prospectus supplement relating to such series. We anticipate that the following provisions will apply to all depositary arrangements.

Generally, ownership of beneficial interests in a book-entry note will be limited to participants that have accounts with the depositary for such book-entry note or persons that may hold interests through participants. Upon the issuance of a book-entry note, the depositary will credit, on its book-entry registration and transfer system, the respective principal amounts of the debt securities represented by such book-entry note to the accounts of participants. The accounts to be credited will be designated by the agents for such debt securities, or by us if we offer and sell such notes directly.

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Ownership of beneficial interests in a book-entry note will be shown on, and the transfer of that ownership will be effected only through, records maintained by the depositary, or by participants or persons that may hold interests through participants. The laws of some states require that some purchasers of securities take physical delivery of such securities in certificated form. Such limits and such laws may impair the ability to transfer beneficial interests in a book-entry note.

So long as the depositary or its nominee is the registered owner of a book-entry note, the depositary or its nominee, as the case may be, will be considered the sole owner or holder of the debt securities represented by such book-entry note for all purposes under the note indenture. Except as provided below, owners of beneficial interests in a book-entry note will not be entitled to have debt securities represented by a book-entry note registered in their names, will not receive or be entitled to receive physical delivery of debt securities in certificated form and will not be considered the owners or holders thereof under the note indenture. Accordingly, each person owning a beneficial interest in a book entry note must rely on the procedures of the depositary and, if such person is not a participant, on the procedures of the participant through which such person owns its interest, to exercise any rights of a holder under the note indenture. We understand that under existing industry practices, if we request any action of holders, or if any owner of a beneficial interest in a book entry note desires to give or take any action allowed under the note indenture, the depositary would authorize the participants holding the relevant beneficial interests to give or take such action, and such participants would authorize beneficial owners owning through such participants to give or take such action or would otherwise act upon the instruction of beneficial owners holding through them.

Interest and Premium

Principal, premium, if any, and interest payments on debt securities represented by a book-entry note will be made to the depositary or its nominee as the registered owner of the book-entry note. We and our agents will have no responsibility or liability for any aspect of the records relating to or payments made on account of beneficial ownership interests in a book-entry note, or for maintaining, supervising or reviewing any records relating to such beneficial ownership interests.

We expect that the depositary, upon receipt of any payment of principal, premium, if any, or interest in respect of a book-entry note, will credit promptly the accounts of the related participants with payment in amounts proportionate to their respective holdings in principal amount of beneficial interest in such book-entry note as shown on the records of the depositary. We also expect that payments by participants to owners of beneficial interests in a book-entry note will be governed by standing customer instructions and customary practices, as is now 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 participants.

Withdrawal of Depositary

If the depositary for any debt securities represented by a book-entry note is at any time unwilling or unable to continue as depositary, or it ceases to be eligible as a depositary under applicable law, and a successor depositary is not appointed by us within 90 days, we will issue debt securities in certificated form in exchange for the relevant book-entry note. In addition, we may at any time determine not to have debt securities represented by one or more book-entry notes, and, in such event, will issue debt securities in certificated form in exchange for the book-entry note or notes representing such debt securities. We understand, however, that under current industry practices The Depository Trust Company would notify its participants of our decision, but will only withdraw beneficial ownership interests from a global security at the request of each participant. Further, if we so specify with respect to a book-entry note, an owner of a beneficial interest in such book-entry note may, on terms acceptable to us and the depositary, receive debt securities in certified form. Any debt securities issued in certificated form in exchange for a book-entry note will be registered in such name or names that the depositary, pursuant to instructions from its direct or indirect participants or otherwise, gives to the trustee.

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PLAN OF DISTRIBUTION

We may sell the securities offered by this prospectus through underwriters or dealers, through agents, directly to one or more purchasers, or through any of these methods of sale. We will describe in the accompanying prospectus supplement the specific plan of distribution, including (i) the identity of any underwriters, dealers or agents and the amount of securities underwritten or purchased by them and their compensation, (ii) the initial offering price of the securities and the proceeds that we will receive from the sale and (iii) any securities exchange on which the securities will be listed.

LEGAL MATTERS

Unless otherwise specified in the prospectus supplement, the validity of the securities and certain other legal matters relating to the offer and sale of the securities offered hereby will be passed upon for us by Kirk Emge, Esq., our General Counsel, and by Covington & Burling LLP, Washington, D.C.

EXPERTS

The financial statements incorporated in this prospectus by reference to Delmarva Power & Light Company’s Annual Report on Form 10-K for the year ended December 31, 2007 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 and other information with the SEC. Our SEC filings are available to the public over the internet at the SEC’s web site at http://www.sec.gov . You may also read and copy any document we file at the SEC’s public reference room at 100 F Street N.E., Washington, D.C. 20549. You can obtain further information on the operation of the public reference room by calling the SEC at 1-800-SEC-0330.

This prospectus is part of a registration statement on Form S-3 filed with the SEC under the Securities Act. It does not contain all of the information that is important to you. You should read the registration statement for further information about us and the debt securities. Statements contained in this prospectus concerning the provisions of any document filed as an exhibit to the registration statement or otherwise filed with the SEC highlight selected information, and in each instance reference is made to the copy of the document filed.

The SEC allows us to “incorporate by reference” the information we file with it, which means that we can disclose important information to you by referring you to those documents. 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 may supersede this information. We incorporate by reference the documents listed below that we have filed with the SEC and any future filing that we make with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act (other than any portions of any such documents that are furnished, rather than filed, by us in accordance with the rules of the SEC under the Securities Exchange Act) prior to the completion of the sales of the securities offered hereby.

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If you make a written or oral request for copies of any of the documents incorporated by reference, we will send you the copies you requested at no charge. However, we will not send exhibits to such documents, unless such exhibits are specifically incorporated by reference in such documents. You should direct requests for such copies to Delmarva Power & Light Company, 701 Ninth Street, N.W., Washington, D.C. 20068, attention: Corporate Secretary. Our telephone number is (202) 872-2900.

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SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, Delmarva Power & Light Company certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-3 and that the security rating requirement under Transaction Requirement B.2 for the debt securities being registered on this form will be met by the time of the sale, and has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Washington, District of Columbia, on the 18 ^th day of November, 2008.

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

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