UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

PURSUANT TO SECTION 13 OR 15(D) OF THE

SECURITIES EXCHANGE ACT OF 1934

Date of Report (Date of earliest event reported): September 4, 2013

SAN DIEGO GAS & ELECTRIC COMPANY

(Exact name of registrant as specified in its charter)

Registrant’s telephone number, including area code: (619) 696-2000

None.

(former name or former address, if changed since last report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

On September 9, 2013, San Diego Gas & Electric Company (the “Company”) closed the public offering and sale of $450,000,000 aggregate principal amount of its 3.60% First Mortgage Bonds, Series NNN, due 2023 (the “Bonds”) with proceeds to the Company (after deducting underwriting discounts but before other expenses estimated at approximately $250,000) of 99.334% of the aggregate principal amount of the Bonds. The sale of the Bonds was registered under the Company’s Registration Statement on Form S-3, as amended (File No. 333-181639). The Bonds were issued pursuant to a Supplemental Indenture, dated as of September 9, 2013, which is attached hereto as Exhibit 4.1. The Bonds will mature on September 1, 2023. Interest on the Bonds accrues from September 9, 2013 and is payable on March 1 and September 1 of each year, beginning on March 1, 2014. The Bonds will be redeemable prior to maturity, at the Company’s option, at the redemption prices and under the circumstances described in the prospectus supplement and the accompanying prospectus relating to the offering filed with the Securities and Exchange Commission on September 5, 2013. Further information regarding the sale of the Bonds is contained in the underwriting agreement, dated September 4, 2013, which is attached hereto as Exhibit 1.1.

(d) Exhibits.

SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

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