Automatic Shelf Registration Statement (Form S-3ASR)

As filed with the U.S. Securities and Exchange Commission on April 21, 2026

Registration No. 333-   

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC 20549

FORM S-3

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

Southern California Gas Company

(Exact Name of Registrant as Specified in Its Charter)

555 West 5^th Street

Los Angeles, California 90013-1011

(213) 244-1200

(Address, Including Zip Code, and Telephone Number, Including Area Code, of Registrant's Principal Executive Offices)

Lisa H. Abbot, Esq.

488 8th Avenue

San Diego, California 92101

(619) 696-2000

(Name, Address, Including Zip Code, and Telephone Number, Including Area Code, of Agent for Service)

Copies to:

Michael E. Sullivan, Esq.

Gregory P. Rodgers, Esq.

Latham & Watkins LLP

12670 High Bluff Drive

San Diego, California 92130

(858) 523-5400

APPROXIMATE DATE OF COMMENCEMENT OF PROPOSED SALE TO THE PUBLIC: From time to time after the effective date of this registration statement.

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. ☒

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. ☒

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. ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of "large accelerated filer," "accelerated filer," "smaller reporting company," and "emerging growth company" in Rule 12b-2 of the Exchange Act.

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of the Securities Act. ☐

PROSPECTUS

SOUTHERN CALIFORNIA GAS COMPANY

First Mortgage Bonds

Senior Debt Securities

Series Preferred Stock

We may offer and sell our first mortgage bonds, senior debt securities and series preferred stock from time to time in one or more offerings. This prospectus provides you with a general description of the securities we may offer.

Each time we offer and sell securities pursuant to this prospectus, we will provide a supplement to this prospectus that contains specific information about the offering and the amounts, prices and terms of the particular securities being offered at that time. The supplement may also add, update or change information contained in this prospectus with respect to that offering. You should carefully read this prospectus and the applicable prospectus supplement before you invest in any of our securities.

We may offer and sell the securities described in this prospectus and any prospectus supplement to or through one or more underwriters, dealers and agents, or directly to purchasers, or through a combination of these methods. If any underwriters, dealers or agents are involved in the offer and sale of any of the securities, their names and any applicable purchase price, fee, commission or discount arrangement between or among them will be set forth, or will be calculable from the information set forth, in the applicable prospectus supplement. See the information under the headings "About this Prospectus" and "Plan of Distribution" for more detail. No securities may be sold without delivery of this prospectus and the applicable prospectus supplement describing the method and terms of the offering of such securities.

Investing in our securities involves risks. See "Risk Factors" on page 6 of this prospectus, and the information under any similar heading in the applicable prospectus supplement.

Neither the U.S. Securities and Exchange Commission nor any state securities commission has approved or disapproved of these 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 April 21, 2026

TABLE OF CONTENTS

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ABOUT THIS PROSPECTUS

This prospectus is part of an "automatic shelf" registration statement that we filed with the U.S. Securities and Exchange Commission, or the "SEC," as a "well-known seasoned issuer" as defined in Rule 405 under the Securities Act of 1933, as amended. By using a shelf registration statement, we may sell the securities described in this prospectus from time to time and in one or more offerings. This prospectus only provides you with a general description of the securities we may offer. Each time that we offer and sell securities, we will provide a prospectus supplement to this prospectus that contains specific information about the securities being offered and sold and the specific terms of that offering. We may also authorize one or more free writing prospectuses to be provided to you that may contain material information relating to that offering. The prospectus supplement or free writing prospectus may also add, update or change information contained in this prospectus with respect to that offering. If there is any inconsistency between the information in this prospectus and the applicable prospectus supplement or free writing prospectus, you should rely on the prospectus supplement or free writing prospectus, as applicable. Before purchasing any securities, you should carefully read both this prospectus and the applicable prospectus supplement (and any applicable free writing prospectus), together with the additional information under the heading "Where You Can Find More Information."

We have not authorized anyone to provide you with any information or to make any representations other than those contained in this prospectus, any applicable prospectus supplement or any free writing prospectuses prepared by or on behalf of us or to which we have referred you. We take no responsibility for, and provide no assurance as to the reliability of, any other information that others may give you. We will not make an offer to sell securities in any jurisdiction where the offer or sale is not permitted. You should assume that the information contained in this prospectus and any applicable prospectus supplement to this prospectus is accurate only as of the date on its respective cover, that the information contained in any applicable free writing prospectus is accurate only as of the date of that free writing prospectus, and that any information contained in documents incorporated by reference is accurate only as of the dates of those respective documents, unless we indicate otherwise. Our business, financial condition, results of operations and prospects may have changed since those dates.

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FORWARD-LOOKING STATEMENTS AND MARKET DATA

This prospectus and the documents incorporated by reference herein contain statements that constitute forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. Forward-looking statements are based on assumptions about the future, involve risks and uncertainties, and are not guarantees. Future results may differ materially from those expressed or implied in any forward-looking statement. These forward-looking statements represent our estimates and assumptions only as of the respective dates of the documents in which such forward-looking statements appear. We assume no obligation to update or revise any forward-looking statement as a result of new information, future events or otherwise.

Forward-looking statements can be identified by words such as "believe," "expect," "intend," "anticipate," "contemplate," "plan," "estimate," "project," "forecast," "envision," "should," "could," "would," "will," "confident," "may," "can," "potential," "possible," "proposed," "in process," "construct," "develop," "opportunity," "preliminary," "pro forma," "strategic," "initiative," "target," "outlook," "optimistic," "poised," "positioned," "maintain," "continue," "progress," "advance," "goal," "aim," "commit," or similar expressions, or when we discuss our guidance, priorities, strategies, goals, vision, mission, projections, intentions or expectations.

Factors, among others, that could cause actual results and events to differ materially from those expressed or implied in any forward-looking statement include:

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We caution you not to rely unduly on any forward-looking statements. You should review and consider carefully the risks, uncertainties and other factors that affect our business as described herein and in our reports and other documents on file with the SEC that are incorporated by reference in this prospectus, any prospectus supplement, and any related free writing prospectus issued by us. You may obtain copies of these reports and documents as described under "Where You Can Find More Information" in this prospectus.

This prospectus incorporates by reference, and any prospectus supplement or free writing prospectus may contain or incorporate by reference market, demographic and industry data and forecasts that are based on or derived from independent industry publications, publicly available information, government data and other information from third parties or that have been compiled or prepared by our management or employees. We do not guarantee the accuracy or completeness of any of this information, and we have not independently verified any of the information provided by third-party sources. In addition, market, demographic and industry data and forecasts that may be contained or incorporated by reference in this prospectus, any prospectus supplement or any free writing prospectus may involve estimates, assumptions and other uncertainties and are subject to change based on various factors, including those discussed under this heading "Forward-Looking Statements and Market Data," under the heading "Risk Factors," and under similar headings in this prospectus, the applicable prospectus supplement, any related free writing prospectus, and documents that are incorporated or deemed to be incorporated by reference in this prospectus and the applicable prospectus supplement. Accordingly, you should not place undue reliance on any of this information.

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WHERE YOU CAN FIND MORE INFORMATION

Available Information

We file annual, quarterly and current reports, information statements and other information with the SEC. The SEC maintains an Internet site that contains reports, proxy and information statements and other information about issuers, such as us, who file electronically with the SEC. The address of that site is http://www.sec.gov.

This prospectus and any prospectus supplement are part of a registration statement that we filed with the SEC and do not contain all of the information in the registration statement. The full registration statement may be obtained from the SEC or from us, as indicated below. Forms of the indentures and other documents establishing the terms of the securities we may offer are or will be filed as exhibits to the registration statement or documents incorporated by reference in the registration statement. Statements in this prospectus or any prospectus supplement about these documents are not complete and each statement is qualified in all respects by reference to the document to which it refers. You should refer to the actual documents for a more complete description of the relevant matters. You may inspect a copy of the registration statement through the SEC's Internet site, as provided above.

Incorporation by Reference

The rules of the SEC allow us to "incorporate by reference" information into this prospectus, which means that we can disclose important information to you by referring you to another document filed separately with the SEC. The information incorporated by reference is deemed to be part of this prospectus, and subsequent information that we file with the SEC that is also incorporated or deemed to be incorporated by reference in this prospectus will automatically update and, to the extent inconsistent, supersede the prior information. Any statement contained in this prospectus or a previously filed document incorporated by reference herein shall be deemed to be modified or superseded for purposes of this prospectus to the extent that a statement contained in this prospectus, any applicable prospectus supplement or any subsequently filed document that is incorporated or deemed to be incorporated by reference in this prospectus modifies or replaces that statement.

We incorporate by reference our documents listed below and all documents that we file with the SEC pursuant to Sections 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934, as amended, which we refer to as the "Exchange Act" in this prospectus, after the date of this prospectus through the termination of the offering of the securities described in this prospectus. Notwithstanding anything herein to the contrary, we are not, however, incorporating by reference any documents or portions thereof or exhibits thereto, whether specifically listed below or filed in the future, that are not deemed "filed" with the SEC, including, without limitation, any information furnished pursuant to Items 2.02 or 7.01 of Form 8-K or related exhibits furnished pursuant to Item 9.01 of Form 8-K.

This prospectus and any applicable prospectus supplement incorporate by reference the documents set forth below that have previously been filed with the SEC:

We will provide, upon written or oral request and without charge, to each person, including any beneficial owner, to whom a copy of this prospectus has been delivered a copy of any of the documents incorporated by

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reference in this prospectus. You may submit such a request by writing or calling us at the following address or telephone number

Southern California Gas Company

555 West 5^th Street

Los Angeles, California 90013

Attention: Corporate Secretary

Telephone: (213) 244-1200

Exhibits to the filings will not be sent, however, unless those exhibits have specifically been incorporated by reference in this prospectus or any applicable prospectus supplement.

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SOUTHERN CALIFORNIA GAS COMPANY

We are a regulated public utility that owns and operates a natural gas distribution, transmission and storage system that delivers natural gas to a service territory that encompasses Southern California and portions of central California (excluding San Diego County, the City of Long Beach and the desert area of San Bernardino County). We are an indirect subsidiary of Sempra, a holding company whose principal businesses are regulated utilities in California and Texas. For additional information concerning us, you should refer to the information under the heading "Where You Can Find More Information" in this prospectus.

Our principal executive offices are located at 555 West 5^th Street, Los Angeles, California 90013 and our telephone number is (213) 244-1200. Our website is http://www.socalgas.com.

Except for documents that are incorporated by reference in this prospectus as described under the heading "Where You Can Find More Information" and that are available on the SEC website at www.sec.gov, the information contained on, or that can be accessed through, our website or any other website referenced herein is not a part of or incorporated by reference in this prospectus or any document incorporated or deemed to be incorporated herein.

In this prospectus, references to "Southern California Gas Company," "we," "us," "our" and similar terms mean, unless otherwise specified or the context otherwise requires, Southern California Gas Company and its consolidated entities (if any); and references to "you" mean the potential purchasers of the applicable securities offered hereby.

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RISK FACTORS

Investment in any securities offered pursuant to this prospectus and the applicable prospectus supplement involves risks. Before deciding whether to invest in any offered securities, you should carefully consider the risk factors and other cautionary language incorporated in this prospectus and the applicable prospectus supplement by reference to our most recent Annual Report on Form 10-K and any Quarterly Reports on Form 10-Q and Current Reports on Form 8-K filed (and not furnished) by us with the SEC subsequent to the last day of the fiscal year covered by our most recent Annual Report on Form 10-K and all other information contained or incorporated by reference in this prospectus, as updated by our subsequent filings under the Exchange Act that are also incorporated by reference in this prospectus, and the risk factors and other information contained and incorporated by reference in the applicable prospectus supplement and any applicable free writing prospectus. Please also carefully read the information under the heading "Forward-Looking Statements and Market Data" and any similar headings in this prospectus, our most recent Annual Report on Form 10-K and any subsequent Quarterly Reports on Form 10-Q and Current Reports on Form 8-K. There may be other risks and uncertainties not known to us or that we deem immaterial that also could impair our business operations, financial results and the value of any securities offered pursuant to this prospectus. The occurrence of any of these risks could have a material adverse effect on our results of operations, financial condition, cash flows and/or prospects and might cause you to lose all or part of your investment in the offered securities.

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USE OF PROCEEDS

We intend to use the net proceeds from the sale of the securities as set forth in the applicable prospectus supplement.

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DESCRIPTION OF FIRST MORTGAGE BONDS

The following is a general description of some of the terms and provisions of the first mortgage bonds we may offer and sell under this prospectus. To the extent the terms and provisions of any series of first mortgage bonds modify the general terms and provisions described below, such modifications will be described in a prospectus supplement or free writing prospectus relating to such series. Under this heading "Description of First Mortgage Bonds," references to "bonds" mean the first mortgage bonds; references to "indenture" mean the first mortgage indenture dated October 1, 1940 between us and U.S. Bank National Association, as successor trustee, relating to the issuance of each series of first mortgage bonds by us, as amended by supplemental indentures dated as of July 1, 1947, August 1, 1955, December 1, 1956, June 1, 1965, August 1, 1972, May 1, 1976 and September 15, 1981; and references to "we," "us," "our" and similar terms mean, unless otherwise specified or the context otherwise requires, Southern California Gas Company excluding its consolidated entities (if any).

The bonds will be governed by the indenture. The indenture gives us broad authority to set the particular terms of each series of bonds, including the right to modify certain of the terms contained in the indenture. The particular terms of a series of bonds and the extent, if any, to which the particular terms of the series modify the terms of the indenture will be described in the applicable prospectus supplement or a free writing prospectus, relating to such series of bonds.

The indenture contains the full legal text of the matters described under this heading "Description of First Mortgage Bonds." The following description of certain provisions of the indenture and the bonds is not complete and is subject to and qualified in its entirety by reference to all the provisions of the indenture, including definitions of terms used in the indenture, and the certificates evidencing the bonds of each series, copies of which have been or will be filed or incorporated by reference as exhibits to the registration statement of which this prospectus is a part or to a document incorporated by reference in this prospectus and which may be obtained as described under the heading "Where You Can Find More Information." We also include references in parentheses to particular sections of the indenture. Whenever we refer to particular sections or defined terms of the indenture in this prospectus or a prospectus supplement or free writing prospectus, those sections or defined terms are incorporated by reference in this prospectus or the applicable prospectus supplement or free writing prospectus. This description also is subject to and qualified by reference to the description of the particular terms of a particular series of bonds described in the applicable prospectus supplement or free writing prospectus related to any offering of such series of bonds.

General

We may issue an unlimited amount of bonds under the indenture in one or more series, subject to the various requirements for the issuance of additional bonds set forth in the indenture, including those described below under "-Issuance of Additional Bonds." Bonds in registered form without coupons may be issued in denominations of $1,000, $5,000, $10,000, $25,000 or integral multiples of $25,000. Bonds will be payable, exchangeable for bonds of other authorized denominations and transferable at the principal office of the trustee in San Francisco, California and any other places designated by us for payment.

Prior to the issuance of each series of bonds, the terms and conditions of the particular series of bonds will be specified in a supplemental indenture. We refer you to the applicable prospectus supplement or free writing prospectus for a description of the following terms of each series of bonds:

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(See Section 2.01.)

Issuance of Additional Bonds

Additional bonds secured by the indenture may be issued in a maximum aggregate principal amount equal to the sum of:

However, the aggregate principal amount of bonds that we can issue under the indenture may not exceed 50% of our Net Investment in Mortgaged Property, after giving effect to the issuance of such additional bonds. (See Section 4.01.) In addition, no additional bonds may be issued under the indenture (except under certain circumstances relating to those issued on the basis of Refundable Bonds) unless the Net Earnings of the Corporation Available for Interest for any 12 consecutive months in the past 15 months equals at least twice our annual interest charges on the sum of (i) all the bonds outstanding under the indenture and such additional bonds, (ii) in the event of our consolidation or merger or transfer of all of our property as an entirety, the indebtedness of any successor corporation maturing more than one year from the date of its creation, but only if such successor corporation does not secure the bonds with a lien on all of its property, other than Excepted Property, and (iii) all of our indebtedness secured by any part of the Mortgaged Property in priority to or pari passu with the lien securing the bonds. (See Section 4.03.)

Other than as described above, the indenture does not limit the amount of indebtedness that we may incur.

Security for the Bonds

The bonds will be secured by the indenture, which constitutes a first lien upon all of our real and personal property other than Excepted Property, subject to easements, rights of way, conditions, reservations and restrictions of record, and to the lien of taxes and assessments not delinquent, and also subject to Permissible Encumbrances, purchase money liens, liens existing on property at the time such property was acquired by us, liens resulting from claims and demands of mechanics, laborers and others the validity of which are being contested in good faith and the prior lien securing the trustee's right to compensation, reimbursement and indemnity. (See granting clauses and Sections 5.09 and 14.10). All of the bonds issued under the indenture will

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be equally and ratably secured by the indenture, subject to the provisions relating to any sinking or similar fund for the benefit of any bonds of a particular series and other than cash held by the trustee for the payment of particular bonds (See Sections 4.01, 5.03 and 10.12).

Subject to limitations and exceptions described in the indenture, all property acquired by us after the date of the indenture, other than Excepted Property, will be further security as described in the indenture. (See Section 5.09.) In addition, the indenture creates a lien on the Mortgaged Property prior to the lien securing the bonds in order to secure the trustee's right to compensation, reimbursement and indemnity. (See Sections 5.17, 6.04, 9.26, 14.10 and 14.11.)

Ranking

The bonds of each series will be our secured and unsubordinated obligations and will rank equally in right of payment with all other bonds issued under the indenture. The bonds will rank first in right of payment with respect to proceeds from Mortgaged Property (subject to easements, rights of way, conditions, reservations and restrictions of record, and to the lien of taxes and assessments not delinquent, and also subject to Permissible Encumbrances, purchase money liens, liens existing on property at the time such property was acquired by us, liens resulting from claims and demands of mechanics, laborers and others the validity of which are being contested in good faith and the prior lien securing the trustee's right to compensation, reimbursement and indemnity), and otherwise will rank equally in right of payment with all of our unsubordinated and unsecured indebtedness, including the senior debt securities. The bonds are Southern California Gas Company's obligations exclusively and are not the obligations of any of our consolidated entities (if any), our parent, Sempra or any of our other affiliates.

Payment of Bonds

We will pay principal of and any premium on the bonds at stated maturity, upon redemption or otherwise, upon presentation of the bonds at the office of the trustee, as our paying agent. We will make payments on the bonds in book-entry form to DTC or its nominee, as the registered owner of the bonds, by wire transfer of immediately available funds.

Form; Transfers; Exchanges

The bonds initially will be issued in book-entry form and represented by one or more global securities deposited with, or on behalf of, DTC, as depositary, and registered in the name of Cede & Co., its nominee. This means that you will not be entitled to receive a certificate for the bonds in book-entry form that you purchase except under the limited circumstances described below under the heading "Global Securities." If any of the bonds are issued in certificated form they will be issued only in fully registered form without coupons, in denominations of $1,000, $5,000, $10,000, $25,000 or integral multiples of $25,000.

You will receive payments and may transfer bonds in book-entry form only through the facilities of DTC and its direct and indirect participants as described below under the heading "Global Securities." We will maintain an office or agency where notices and demands in respect of the bonds and the indenture may be delivered to us and where certificated bonds may be surrendered for payment, registration of transfer or exchange, which will be at the principal office of the trustee in San Francisco, California and any other places specified in the applicable prospectus supplement or free writing prospectus. (See Sections 2.01, 2.03 and 2.04.)

There will be no service charge for (i) any registration or transfer of the bonds, but we may impose a charge sufficient to reimburse us for any tax or governmental charge required to be paid with respect to any such registration or transfer, or (ii) any exchange of the bonds, but we may charge a sum not exceeding $2 for each bond issued upon any such exchange and a further sum sufficient to reimburse us for any stamp taxes or other governmental charges. We may block the transfer or exchange of bonds for a period of 10 days prior to any interest payment date. (See Sections 2.03 and 2.04.)

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Optional Redemption

We may from time to time redeem, at our option, all or any part of the bonds of any series at the redemption price specified therein for such series of bonds. In the event that we elect to redeem only a portion of a series of bonds, the bonds to be redeemed shall be selected by the trustee by lot in such manner as it shall deem fair, in the case of bonds that are not represented by one or more global securities, or in accordance with the procedures of DTC, in the case of bonds represented by one or more global securities if so provided in the applicable prospectus supplement or free writing prospectus. (See Section 7.01.)

Any other redemption provisions applicable to the bonds of any series will be set forth in the applicable prospectus supplement or free writing prospectus.

We will mail notice of any redemption at least 30 days but not more than 60 days before the redemption date to each holder of the bonds to be redeemed. (See Section 7.02.) On or prior to the redemption date, we will deposit with the trustee a sum of money sufficient to redeem the bonds designated for redemption to be held in trust for the account of the holders thereof. Following notice of redemption and deposit of the redemption price with the trustee on or before the applicable redemption date, the bonds or portions thereof called for redemption shall cease to bear interest and shall cease to be entitled to the lien of the indenture after such redemption date. (See Section 7.03.) Upon surrender of the bonds, we will pay the holders of the surrendered bonds the principal, premium (if any) and accrued interest of the redeemed bonds or, if only a portion of the principal of a particular bond is being redeemed, we will pay such holders that portion of the principal, premium (if any) and interest attributable to such redeemed portion and the trustee will deliver new bonds in lieu of the unredeemed portion without charge. (See Sections 7.04 and 7.05.) All of the bonds redeemed and paid shall be cancelled. (See Section 7.06.)

Renewal Fund

We will pay or cause to be paid to the trustee annually on April 1, as a renewal fund, an amount equal to (1) the amounts actually appropriated by us from earnings during the preceding calendar year as provisions for depreciation, depletion and retirements of Mortgaged Property and, if such appropriations are calculated on a sinking fund or similar compound interest method, including the portion thereof representing interest accrual as well as the portion thereof representing the annuity charge, minus (2) credits (which may include credits from prior years), taken at our option, for:

(See Sections 8.02 and 8.04.)

Renewal fund payments that we pay in cash and any other monies held by the trustee as part of the Mortgaged Property may, at our option:

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(See Sections 8.06, 10.08, 10.09 and 10.11.)

In addition, any cash in excess of $100,000 held by the trustee as part of the Mortgaged Property for more than three years after deposit shall be applied by the trustee to the purchase or redemption of outstanding bonds. (See Section 10.11.)

Instead of making all or any portion of such a renewal fund payment in cash, we may deliver outstanding bonds to the trustee, which will be deemed equivalent to payment of cash in an amount equal to the aggregate principal amount of the bonds so delivered. (See Section 8.05.)

At our election, the amount of any required renewal fund payment may be reduced by an amount equal to the amount of cash which, assuming that the renewal fund payments required to be made pursuant to the indenture had actually been made in cash, could at the time be withdrawn under the indenture. (See Section 8.06.) Any payments that we make to the renewal fund are in addition to the expenditures we are required to make for maintenance.

Consolidation, Merger and Transfer of Assets

Nothing in the indenture or in the bonds outstanding under the indenture prevents us from consolidating or merging with or into any corporation or selling all of our property as an entirety subject to the continuing lien of the indenture, if:

(See Section 15.01.)

In the case of a consolidation or merger with or into any other corporation or of a sale of our property as an entirety, the successor corporation or purchasing corporation, as applicable, upon executing and causing to be recorded an indenture to the trustee, shall succeed to and be substituted for us under the indenture and the bonds. (See Section 15.02.) Notwithstanding the foregoing, the indenture shall not become a lien or charge on any properties or franchises of the successor corporation, whether owned at the time of such transaction or thereafter acquired, except for the properties and franchises subject to the lien of the indenture prior to such transaction (and all substitutions, replacements, accessions, additions, alterations, improvements, betterments, developments, extensions and enlargements to, of or upon any of the properties which then are or may thereafter become subject to the lien of the indenture) and any property and franchises which the successor corporation may voluntarily subject to the lien of the indenture. (See Section 15.03.)

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Events of Default

The following events are defined for all purposes of the indenture (except where the term is otherwise defined for specific purposes) as "events of default":

unless during such period such adjudication, order or appointment of a receiver or trustee shall be vacated;

(See Section 9.02.)

Remedies

Acceleration

Upon the occurrence of an event of default, the trustee may, and upon the written request of the holders of a majority in principal amount of the bonds then outstanding shall, by written notice to us, declare the principal amount of all bonds then outstanding under the indenture, together with accrued and unpaid interest thereon, to be immediately due and payable. (See Section 9.05.)

Rescission of Acceleration

If, at any time after the principal of the bonds shall have been declared due and payable and before any sale of the Mortgaged Property shall have been made pursuant to the indenture,

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shall either by paid by us to those entitled thereto (or to the trustee for their account) or be collected out of the Mortgaged Property, and all other defaults existing under the indenture known to the trustee shall have been cured or provision deemed by the trustee to be adequate therefor shall have been made, or shall have been waived as provided in the indenture, then and in every such case:

and the parties shall be restored to their respective rights and obligations under the indenture as if no default had occurred; but no such waiver of any particular default shall extend to or affect or be deemed a waiver of any other default or impair any right consequent thereon. (See Section 9.05.)

Remedies with Respect to Mortgaged Property

To the extent permitted by law, upon the occurrence of an event of default, the trustee may enter, hold, use, operate, manage and control all or any part of the Mortgaged Property and conduct the business thereof, either personally or through the trustee's agents. Upon every such entry, the trustee, from time to time, either by purchase, repair or construction, may maintain, restore and insure the buildings and structures and property in the same manner and to the same extent as us and may make all necessary and proper repairs, renewals and replacements, improvements, extensions and additions thereto as may seem judicious to the trustee and may deduct such expenses out of the Mortgaged Property. If the trustee enters the Mortgaged Property as aforesaid, the trustee will be entitled to receive the earnings, income, rents, issues and profits from the Mortgaged Property and, after deducting the expenses of conducting the business of and operating the Mortgaged Property and of all such repairs, renewals and replacements, improvements, extensions and additions and all payments for taxes, assessments, insurance and other proper charges upon the Mortgaged Property, or any part thereof, as well as just and reasonable compensation to the trustee and its agents and counsel for their respective services, will apply such money in the following manner:

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Any surplus remaining after providing for such payments and for the payment of all installments of interest becoming due in the following six months shall be paid over to us, or whosoever may be entitled to receive the same, or as any court of competent jurisdiction may direct. (See Section 9.04.)

If one or more events of default occurs and continues without remedy for the designated period, the trustee may, in every such case, sell the Mortgaged Property or take appropriate judicial proceedings for the protection and enforcement of its rights and the rights of the bondholders. (See Section 9.06.) In the case of the sale of the Mortgaged Property, whether made under the power of sale granted in the indenture or pursuant to judicial proceedings, the principal of all outstanding bonds, if not previously due, shall immediately become due and payable. (See Section 9.14.) The proceeds of any sale of the Mortgaged Property made under the power of sale given by the indenture or pursuant to judicial proceedings, together with any other amounts held by the trustee as part of the Mortgaged Property or proceeds thereof (except such part as may be held in trust for payment of bonds already called for redemption or previously matured and matured interest as provided in the indenture), shall be applied as follows:

(See Section 9.15.)

In the case of a default in the payment of the principal of any bond that has become due and payable or the payment of interest on any bond for a period of 30 days after such interest has become due and payable, the trustee may recover a judgment, in its own name and as trustee of an express trust, against us for the whole amount of such principal and interest that remains unpaid, together with interest on such unpaid principal and, to the extent legally enforceable, on such unpaid interest. The trustee may file proof of such claim and any other papers or documents as may be necessary or advisable in order to have such claims allowed in judicial proceedings relative to us or our creditors or our property. Any monies collected by the trustee pursuant to any such judgment shall be applied as follows:

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(See Section 9.17.)

The indenture provides that neither (a) any claim for interest on any bond which has been extended in contravention of the provisions of the indenture nor (b) any claim for interest on any bond which at or after maturity has been transferred or pledged separate from such bond, unless accompanied by such bond, shall be entitled, upon any event of default, to any benefit under the indenture, except after the prior payment in full of the principal of all bonds and interest thereon not so extended, transferred or pledged. (See Section 9.01.)

Notice Regarding Remedies with Respect to Mortgaged Property

Any foreclosure on the Mortgaged Property by the trustee may be limited by applicable law. With respect to Mortgaged Property located in California, Section 726 of the California Code of Civil Procedure provides that any action to recover on a debt or enforce any right secured by a mortgage on real property or an estate for years therein must comply with the provisions of that section, which provisions relate to and specify the procedures for the sale of encumbered property or an estate for years therein, the application of proceeds, the rendition in certain cases of a deficiency judgment, and other related matters. Judicial decisions interpreting Section 726 have formulated principles requiring that only one action may be brought to enforce an obligation secured by a lien on California real property, that all security for the obligation must be included in one foreclosure action, and that the creditor must exhaust all of its security before a personal judgment or other recovery may be obtained against the debtor for a deficiency. We advise you that failure to comply with Section 726 as it has been interpreted may result in the extinguishment of the liens on the Mortgaged Property and the loss of your right to a deficiency judgment.

Control by Holders; Limitations

The holders of a majority in principal amount of the bonds then outstanding have the right to direct the time, method and place of conducting any proceeding for any remedy available to the trustee or exercising any trust or power given to the trustee. The trustee may and, upon the written request of the holders of a majority in principal amount of the bonds then outstanding (including, if more than one series of bonds is outstanding, the holders of a majority in principal amount of the bonds of each such series), shall waive any default under the indenture and its consequences, other than a payment default. (See Sections 9.22 and 9.28.)

In addition, the indenture provides that no holder of bonds will have any right to institute any suit, action or proceeding, at law or in equity, for the foreclosure of the indenture, the execution of any trust with respect to the indenture, the appointment of a receiver, or any other remedy under the indenture unless:

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(See Section 9.20.)

No holder will be entitled to take any action to affect, disturb or prejudice the lien of the indenture, or to enforce any right under the indenture, except in the manner specified in the indenture, and actions must be instituted and maintained only in the manner provided by the indenture and for the equal benefit of all holders of outstanding bonds. Notwithstanding the foregoing, the right of any holder of any bond to receive payment of the principal of and interest on such bond when due, and to institute suit for the enforcement of such payment, shall not be impaired or affected without the consent of such holder, except that no bondholder may institute any such suit if and to the extent it would result in the surrender, impairment, waiver or loss of the lien of the indenture upon any of the Mortgaged Property. (See Sections 9.20 and 9.21.)

Notice of Default

The trustee is required to give the bondholders notice of any default under the indenture known to the trustee, unless the default has been cured, within 90 days after the occurrence of the default; provided that except in the case of default in the payment of principal of or interest on any bonds, or in the payment of any maintenance and sinking fund installment or of any sinking fund or purchase fund installment, the trustee may withhold notice of default if and so long as its board of directors, its executive committee or a trust committee of directors and/or responsible officers of the trustee in good faith determine that the withholding of notice is in the interest of the bondholders. (See Section 9.03.) As used in this paragraph, the term "default" means any event of default, not including any grace period provided for in such event of default.

Modification of the Indenture

The indenture may be modified by us and the trustee with the consent of the holders of at least 66 ²/₃% in principal amount of the bonds then outstanding, and, in case one or more but less than all series of bonds then outstanding are affected by the modification, by the consent of the holders of at least 66 ²/₃% in principal amount of the bonds of such series affected; provided that the right of any holder to receive payment of principal and interest when due or to institute suit for the enforcement of such payment may not be impaired or affected without the consent of such holder (except that no bondholder may institute any such suit if and to the extent it would result in the surrender, impairment, waiver or loss of the lien of the indenture upon any of the Mortgaged Property), and no such modification shall reduce the proportion of bondholders' consents required for any such modification. (See Sections 9.21 and 16.05.)

We may, without the consent of any bondholders, and at our request the trustee shall, enter into supplemental indentures amending the indenture to, among other things:

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Any such supplemental indenture shall comply with the Trust Indenture Act of 1939, as amended, and shall be binding upon the holders of all bonds, as fully as though the provisions of such supplemental indenture were a part of the indenture. (See Sections 16.01 and 16.03.)

Defeasance, Cancellation and Discharge

The lien on our property securing the bonds will be cancelled and discharged when the principal of and interest on all then outstanding bonds has been paid or when we deposit with the trustee sufficient funds to pay the principal of and interest on all then outstanding bonds, and when all other sums due and payable by us under the indenture have been paid or satisfactorily provided for, including the compensation and expenses of the trustee, and we request that the Mortgaged Property revert to us and that the lien be cancelled and discharged. Unless we request cancellation and discharge, the lien created by the indenture will not be cancelled and discharged, but shall remain in place for the issuance of future bonds pursuant to the terms of the indenture. (See Sections 11.01 and 11.02.)

Release Provisions

Unless an event of default has occurred and is continuing, we may, free from the lien of the indenture and at any time and from time to time, without any release by the trustee, sell, exchange or dispose of worn out, unserviceable, undesirable or unnecessary machinery or equipment, provided we replace the machinery and equipment with other machinery and equipment of equivalent or greater value. (See Section 10.02.) Unless an event of default has occurred and is continuing, we may also at any time and from time to time, without any release by the trustee:

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(See Section 10.03.)

The indenture also contains provisions for the release of property by the trustee (i) upon a sale or other disposition of such property provided that no event of default has occurred and is continuing, that we receive consideration at least equal to the fair value of the property, that the release is advantageous in the conduct of the business and will not impair the security of the Mortgaged Property under the indenture in contravention of the provisions thereof, and that we deposit cash with the trustee, as part of the Mortgaged Property, in an amount at least equal to the fair value of the property released (provided that the amount of cash deposited shall be reduced by, among other things, any purchase money mortgages on the property to be released that are deposited with the trustee and by any interest-bearing obligations issued by any municipal corporation or other governmental subdivision that are deposited with the trustee; and provided, further, that the cash so deposited may also be reduced by the amount of cash which we could at the time withdraw from the Mortgaged Property on the basis of Property Additions or Refundable Bonds) and (ii) for property taken by eminent domain, provided that the proceeds of any taking by eminent domain are deposited with the trustee. (See Sections 10.04 and 10.05.)

As described above under "-Renewal Fund," we may also withdraw cash that is part of the Mortgaged Property, subject to specified conditions, in an amount equal to the lesser of the cost or fair value of specified Property Additions purchased, constructed or otherwise acquired by us, or in an amount equal to the amount of Refundable Bonds made the basis for withdrawal, or cause cash that is part of the Mortgaged Property to be used to purchase or redeem outstanding bonds, subject to specified conditions. (See Sections 10.08, 10.09 and 10.11.) In addition, any cash in excess of $100,000 held by the trustee as part of the Mortgaged Property for more than three years after deposit shall be applied by the trustee to the purchase or redemption of outstanding bonds. (See Section 10.11.)

Monies deposited with the trustee upon the release or condemnation of Non-Bondable Property or insurance proceeds deposited with the trustee on account of loss of or damage to Non-Bondable Property shall, at our request, be paid to us in an amount equal to the lesser of the cost or fair value of other Non-Bondable Property purchased, constructed or otherwise acquired by us, subject to specified conditions. (See Section 10.10.)

However, unless the Mortgaged Property is in the possession of a receiver, trustee in bankruptcy or assignee for the benefit of creditors, no cash held as part of the Mortgaged Property shall be paid to us or applied to the purchase or redemption of bonds pursuant to specified sections of the indenture if we are, to the knowledge of the trustee, in default under the indenture or if an event of default has occurred and is continuing. (See Section 10.14.)

Evidence of Compliance

The indenture provides that we will furnish to the trustee officers' certificates, and, in certain cases, engineer's certificates or independent engineer's certificates and independent public accountant's certificates in connection with the authentication of any bonds, the release or release and substitution of certain property and certain other matters, and opinions of counsel as to the lien of the indenture and certain other matters. (See Sections 4.03, 4.04, 4.07, 8.03, 10.03, 10.04, 10.08 and 10.11.)

Concerning the Trustee

The trustee may resign at any time by giving us written notice and by publishing notice in a required newspaper. The resignation will be effective either on the date specified in the notice or on the date of

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appointment of a successor trustee. The holders of a majority in principal amount of the bonds then outstanding may remove the trustee by signing, acknowledging and filing with the trustee a written instrument or concurrent written instruments. We may appoint a successor trustee unless and until a successor trustee is appointed by the holders of a majority in principal amount of the bonds then outstanding. (See Sections 14.16, 14.17 and 14.18.)

No Liability for Shareholders, Directors and Officers

None of our past, present or future shareholders, directors or officers will be liable for any payments of principal of or interest on the bonds, or for any claim based on any payment of principal or interest, or on the indenture or any supplemental indenture. (See Article XII.)

Governing Law

Each supplemental indenture establishing the terms of a series of bonds shall provide that such bonds, such supplemental indenture and the indenture will be governed by and construed in accordance with the laws of the State of California, without regard (to the extent permitted by applicable law) to conflicts of laws principles thereof.

Defined Terms

Set forth below are certain defined terms used in the indenture and in this description. Reference is made to the indenture for complete definitions of all such terms, as well as any other capitalized terms used in this prospectus for which no definition is provided. (See granting clauses and Article I.)

"Bondable Property" means all property owned by us on December 31, 1954, of the same nature as property defined in the indenture as Property Additions, and all Property Additions purchased, constructed, or otherwise acquired by us on or after January 1, 1955.

"Excepted Property" means all of the following property, whether owned on the date of the original indenture or thereafter acquired by us, all of which shall be excepted and excluded from the Mortgaged Property and the lien of the indenture (as used below in this definition, references to "now" mean October 1, 1940, the date of the original indenture, and references to "hereafter" mean after such date):

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"Gross Property Additions" means, as applied to any particular period, all of the Property Additions purchased, constructed or otherwise acquired by us during such period, including Property Additions purchased, constructed or otherwise acquired during such period, but retired during such period.

"Mortgaged Property" means as of any particular time the property which at said time is covered or intended to be covered by the lien of the indenture; provided that moneys held by the trustee in trust for the payment, at maturity or on a date fixed for redemption, of specific bonds shall not be deemed to be a part of the Mortgaged Property.

"Net Bondable Value of Property Additions" means, at any particular time, the aggregate of the cost to us or, as to such Property Additions which have not been retired, the fair value to us, if the fair value is less than cost, of all Gross Property Additions purchased, constructed or otherwise acquired by us, after deducting therefrom the amounts specified in the following paragraphs (1), (2) and (3) and the greater of the amounts specified in the following paragraphs (A) or (B) after each of the amounts specified in said paragraphs (A) and (B) has been reduced by the amount of all credits taken on the basis of cash and bonds delivered to the trustee:

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"Net Earnings of the Corporation Available for Interest" means our net earnings ascertained as follows:

"Net Investment in Mortgaged Property" means as of any particular time the total cost of the Mortgaged Property less the then related reserves for depreciation, depletion and amortization or other reserves for

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retirement of such property; all determined in compliance with the Uniform System of Accounts for Gas Corporations prescribed by the CPUC, effective January 1, 1949, or in compliance with such system of accounts as the CPUC or other similar regulatory body may from time to time prescribe, or to the extent that any such system is not so prescribed or is not applicable, then in accordance with sound accounting practice.

"Non-Bondable Property" means any property (other than Bondable Property) owned by us on December 31, 1954, or purchased, constructed, or otherwise acquired by us after that date.

"Permissible Encumbrances" means:

"Property Additions" means, subject to certain exceptions pursuant to the terms of the indenture, any new or additional property, real or personal (including separate systems), and improvements, extensions, or additions (including in these terms equipment and appliances installed as part of our fixed property) to or about our plants, systems or properties, purchased, constructed, or otherwise acquired by us on or after January 1, 1955, and in every case properly chargeable to fixed property accounts, and used or useful for the business of purchasing, manufacturing, transporting, transmitting, distributing or supplying natural, manufactured or mixed gas and/or electricity for heat, fuel, light, power, refrigeration or other purposes and may include, subject to the foregoing, property acquired by us or by a successor corporation as a result of any consolidation or merger to which we or any successor corporation are a party; permanent improvements, extensions or additions to our properties in the process of construction or partially completed, in so far as actually constructed or completed; property purchased, constructed, or otherwise acquired to replace property retired; and rights of way, easements, property installed by us upon any such right of way or easement and improvements that are held by us, subject to the lien of the indenture and in or upon any public highway. The term "Property Additions" shall not include, among other things, goodwill; leases, operating agreements, contracts or franchises or governmental permits; shares of stock, evidences of indebtedness or any other securities; gas and/or oil acreage, wells, reserves, leaseholds or related property or equipment; merchandise acquired for resale; materials or supplies to be used for fixed capital purposes or in our operations; motor vehicles; or property subject to any liens other than Permissible Encumbrances.

"Refundable Bonds" means, at any particular time, all bonds which have been previously authenticated and delivered under the provisions of the indenture and issued by us and bonds, not issued by us, which have been

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established as refundable pursuant to the indenture; provided that such bonds, whether authenticated under the indenture or established as refundable, shall have been previously paid at maturity or redeemed or purchased (otherwise than out of funds included in the Mortgaged Property) and surrendered to the trustee, either canceled or uncanceled, or otherwise surrendered to the trustee, subject to certain exceptions provided in the indenture, and which shall not previously have been made the basis for the authentication and delivery of additional bonds or the withdrawal of cash under the indenture or the reduction of the amount of cash to be deposited under the indenture or paid or redeemed or purchased pursuant to, or used to reduce the amount of cash to be deposited pursuant to, or otherwise retired through the operation of, or used in compliance with the requirements of, the provisions of the maintenance and sinking fund established by the indenture or of any sinking fund, amortization fund, or analogous fund established by any supplemental indenture, which does not permit the authentication of additional bonds upon the basis of bonds so paid, redeemed, purchased, retired or used. Bonds and coupons for the payment or redemption of which moneys shall have been deposited (whether at or prior to maturity or the redemption date of such bonds) with the trustee if such bonds were issued under the indenture, or with the trustee of the other indenture under which such bonds were issued, shall be deemed to have been paid within the meaning of this definition; provided, however, that if such bonds are to be redeemed prior to the maturity thereof, notice of such redemption shall be given as provided in the indenture or pursuant to the redemption provisions of such other indenture, as the case may be, or provisions satisfactory to the trustee shall have been made for such publication.

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DESCRIPTION OF SENIOR DEBT SECURITIES

The following is a general description of some of the terms and provisions of the senior debt securities we may offer and sell under this prospectus. To the extent the terms and provisions of any series of senior debt securities modify the general terms and provisions described below, such modifications will be described in a prospectus supplement or free writing prospectus relating to such series. Under this heading "Description of Senior Debt Securities," references to "indenture" mean the senior indenture dated as of September 21, 2020 between us and U.S. Bank Trust Company, National Association, as successor trustee; and references to "we," "us," "our" and similar terms mean, unless otherwise specified or the context otherwise requires, Southern California Gas Company excluding its consolidated entities (if any).

The senior debt securities will be governed by the indenture. The indenture gives us broad authority to set the particular terms of each series of senior debt securities, including the right to modify certain of the terms contained in the indenture. The particular terms of a series of senior debt securities and the extent, if any, to which the particular terms of the series modify the terms of the indenture will be described in the applicable prospectus supplement or a free writing prospectus, relating to such series of senior debt securities.

The indenture contains the full legal text of the matters described under this heading "Description of Senior Debt Securities." The following description of certain provisions of the indenture and our senior debt securities is not complete and is subject to and qualified in its entirety by reference to all the provisions of the indenture, including definitions of terms used in the indenture, and the certificates evidencing the senior debt securities of each series, copies of which have been or will be filed or incorporated by reference as exhibits to the registration statement of which this prospectus is a part or to a document incorporated by reference in this prospectus and which may be obtained as described under the heading "Where You Can Find More Information." We also include references in parentheses to particular sections of the indenture. Whenever we refer to particular sections or defined terms of the indenture in this prospectus or a prospectus supplement or free writing prospectus, those sections or defined terms are incorporated by reference in this prospectus or the applicable prospectus supplement or free writing prospectus. This description also is subject to and qualified by reference to the description of the particular terms of a particular series of senior debt securities described in the applicable prospectus supplement or free writing prospectus related to any offering of such series of senior debt securities.

General

We may issue an unlimited amount of senior debt securities under the indenture in one or more series. We are not required to issue all senior debt securities of one series at the same time and, unless otherwise provided for a particular series of senior debt securities in the applicable prospectus supplement or a free writing prospectus, we may, without notice to or consent of the holders of the senior debt securities of any series, increase the aggregate principal amount of the debt securities of any series and issue additional debt securities of such series up to the maximum aggregate principal amount authorized with respect to such series as increased from time to time. Any additional senior debt securities so issued shall have the same form and terms (other than offering price, the date of issuance and, under certain circumstances, the date from which interest thereon shall begin to accrue and the first interest payment date) and shall carry the same right to receive accrued and unpaid interest as the senior debt securities previously issued, and such additional senior debt securities shall form a single series with the senior debt securities previously issued under the indenture, provided that such additional senior debt securities of such series shall be fungible with the senior debt securities of such series previously issued for United States federal income tax purposes.

Unless otherwise provided in a prospectus supplement or free writing prospectus, our senior debt securities will not be subject to a sinking fund or entitled to any guarantees and you will not be permitted to require us to redeem or repurchase the senior debt securities at your option.

Unless otherwise provided in a prospectus supplement or free writing prospectus, the trustee shall serve as the initial paying agent and security registrar for our senior debt securities.

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Prior to the issuance of each series of senior debt securities, the terms of the particular series of senior debt securities will be specified in either a supplemental indenture or a board resolution and one or more officers' certificates. We refer you to the applicable prospectus supplement or free writing prospectus for a description of the following terms of each series of senior debt securities:

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(See Section 301.)

Ranking

The senior debt securities will be our unsecured and unsubordinated obligations and will rank equally in right of payment with all of our other unsecured and unsubordinated indebtedness. The senior debt securities are the obligations of Southern California Gas Company exclusively, and are not the obligations of our consolidated entities (if any), our parent, Sempra, or any of our other affiliates. Although the senior debt securities will be our senior unsubordinated obligations, the outstanding first mortgage bonds will have a claim to the assets securing the first mortgage bonds prior to any claim by holders of the senior debt securities.

Payment of Senior Debt Securities

We will pay interest on the senior debt securities on each interest payment date to the person in whose name the senior debt securities are registered as of the close of business on the regular record date relating to the interest payment date.

However, if we default in paying interest on a senior debt security, we will pay defaulted interest, at our election, in either of the two following ways:

(See Section 307.)

We will pay principal of and any premium on the senior debt securities at stated maturity, upon redemption or as otherwise required, upon presentation of the senior debt securities at the office of the paying agent, which initially will be the trustee or such other paying agent designated in accordance with the indenture. Any other paying agent initially designated for the senior debt securities of a particular series will be named in the applicable prospectus supplement or free writing prospectus. In our discretion, we may remove and/or appoint one or more additional paying agents and change or designate one or more additional places for payment. A place for payment of the senior debt securities will be provided in the Borough of Manhattan, The City of New York, New York. (See Section 1002.)

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If any interest payment date, redemption date or the maturity date of the senior debt securities is not a business day at any place of payment, then payment of the principal and premium, if any, or interest, as applicable, may be made on the next business day at that place of payment. In that case, no interest will accrue on the amount payable for the period from and after the applicable interest payment date, redemption date or maturity date, as the case may be. (See Section 113.)

Form; Transfers; Exchanges

The senior debt securities initially will be issued in book-entry form and represented by one or more global securities deposited with, or on behalf of, The Depository Trust Company, New York, New York, as depositary, which we refer to as "DTC" or the "depositary" in this prospectus, and registered in the name of Cede & Co., its nominee. This means that you will not be entitled to receive a certificate for the senior debt securities that you purchase except under the limited circumstances described below under the heading "Global Securities." If any of the senior debt securities are issued in certificated form they will be issued only in fully registered form without coupons, in denominations of $2,000 and integral multiples of $1,000. (See Section 302.)

You will receive payments and may transfer senior debt securities in book-entry form only through the facilities of DTC and its direct and indirect participants as described below under the heading "Global Securities." We will maintain an office or agency in the Borough of Manhattan, The City of New York where notices and demands in respect of the senior debt securities and the indenture may be delivered to us and where certificated senior debt securities may be surrendered for payment, registration of transfer or exchange. That office or agency will initially be an office of the trustee, which is currently located at 100 Wall Street, Suite 1600, New York, New York 10005. (See Section 1002.)

You may have your certificated senior debt securities divided into senior debt securities of smaller authorized denominations, or combined into senior debt securities of larger authorized denominations, as long as the total principal amount is not changed. This is called an "exchange." (See Section 305.)

You may exchange or transfer certificated senior debt securities at the office of the trustee, as security registrar. The security registrar acts as our agent for registering senior debt securities in the names of holders and transferring and exchanging senior debt securities. (See Section 305.)

In our discretion, we may change the place for registration of transfer and exchange of the senior debt securities and for delivery of notices and demands in respect of the senior debt securities and the indenture, and we may remove and/or appoint one or more additional security registrars or act as our own agent for this purpose. (See Sections 305 and 1002.)

There will be no service charge for any transfer or exchange of the senior debt securities, but you may be required to pay a sum sufficient to cover any tax or other governmental charge payable in connection with the transfer or exchange. We may block the transfer or exchange of (i) any senior debt securities during a period of 15 days before mailing any notice of redemption of such senior debt securities or (ii) any senior debt security selected for redemption in whole or in part, except the unredeemed portion of any senior debt security being redeemed in part. (See Section 305.)

Optional Redemption

The redemption provisions, if any, applicable to the senior debt securities of any series will be set forth in the applicable prospectus supplement or free writing prospectus.

We will mail notice of any redemption at least 30 days, but not more than 60 days, before the redemption date to each registered holder of the senior debt securities to be redeemed. Once notice of redemption is mailed, the senior debt securities called for redemption will become due and payable on the redemption date and at the

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applicable redemption price, plus any accrued and unpaid interest to the redemption date. If we elect to redeem all or a portion of the senior debt securities, that redemption will not be conditional upon receipt by the trustee or other paying agent of monies sufficient to pay the redemption price. (See Section 1104.)

Unless we default in payment of the redemption price and accrued interest, if any, from and after the redemption date the senior debt securities or portions thereof called for redemption will cease to bear interest. We will pay the redemption price and any accrued interest once the senior debt securities are surrendered for redemption. (See Section 1105.) If only part of a senior debt security is redeemed, the trustee will deliver new senior debt securities of the same series for the remaining portion without charge. (See Section 1106.)

In the event that we elect to redeem only a portion of the senior debt securities, the senior debt securities to be redeemed will be selected in accordance with the procedures of DTC, in the case of senior debt securities represented by one or more global securities, or by the trustee by a method the trustee deems to be fair and appropriate, in the case of senior debt securities that are not represented by one or more global securities. (See Section 1103.)

Events of Default

An "event of default" occurs with respect to the senior debt securities of any series if:

(See Section 501.)

No event of default with respect to a series of senior debt securities necessarily constitutes an event of default with respect to the senior debt securities of any other series issued under the indenture.

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Remedies

Acceleration

If an event of default occurs and is continuing with respect to any series of senior debt securities, then either the trustee or the registered holders of at least 33% in principal amount of the outstanding senior debt securities of that series may declare the principal amount of all of the senior debt securities of that series, together with accrued and unpaid interest thereon, to be due and payable immediately, and upon any such declaration the principal of and accrued and unpaid interest on the senior debt securities of that series shall become immediately due and payable (notwithstanding, if the terms of the senior debt securities of such series permit us to defer or extend the payment of interest thereon, any such extension or deferral). (See Section 502.)

Rescission of Acceleration

After the declaration of acceleration has been made with respect to any series of senior debt securities and before the trustee has obtained a judgment or decree for payment of the money due, the event of default giving rise to the declaration will be deemed to have been waived and the declaration and its consequences will be rescinded and annulled if:

(See Section 502.)

For more information as to waiver of defaults, see "-Waiver of Default and of Compliance" below.

Control by Registered Holders; Limitations

If an event of default with respect to the senior debt securities of any series occurs and is continuing, the registered holders of a majority in principal amount of the outstanding senior debt securities of that series, voting as a single class without regard to the holders of outstanding senior debt securities of any other series that may also be in default, will have the right to direct the time, method and place of:

These rights of registered holders to give directions are subject to the following limitations:

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The trustee may also take any other action it deems proper which is not inconsistent with the registered holders' direction. (See Sections 512 and 603.)

In addition, the indenture provides that no registered holder of senior debt securities of any series will have any right to institute any proceeding, judicial or otherwise, with respect to the indenture or for the appointment of a receiver or for any other remedy under the indenture unless:

Furthermore, no registered holder will be entitled to institute any action if and to the extent that the action would affect, disturb or prejudice the rights of other registered holders of senior debt securities. (See Section 507.)

However, each registered holder has an absolute and unconditional right to receive payment when due and to bring a suit to enforce that right. (See Section 508.)

Notice of Default

The trustee is required to give the registered holders of senior debt securities of the affected series notice of any default under the indenture with respect to the senior debt securities of that series to the extent required by the Trust Indenture Act; except that in the case of an event of default of the character specified above in the fourth bullet under "-Events of Default," no notice will be given to such registered holders until at least 30 days after the occurrence of the default. (See Section 602.) The Trust Indenture Act currently permits the trustee to withhold notices of default (except for certain payment defaults) if the trustee in good faith determines the withholding of the notice to be in the interests of the registered holders.

We will furnish the trustee with an annual statement of whether we are in default in the performance or observance of any of the terms, provisions and conditions in the indenture. (See Section 1005.)

Waiver of Default and of Compliance

The registered holders of a majority in principal amount of the outstanding senior debt securities of any series, voting as a single class without regard to the holders of outstanding senior debt securities of any other series, may waive, on behalf of all registered holders of the senior debt securities of that series, any past default under the indenture, except a default in the payment of principal, premium (if any) or interest, or with respect to compliance with certain covenants or provisions of the indenture that cannot be modified or amended without the consent of the registered holder of each outstanding senior debt security of that series. (See Section 513.)

Compliance with certain covenants in the indenture or otherwise provided with respect to senior debt securities of any series may be waived before the time specified for compliance by the registered holders of a majority in principal amount of the outstanding senior debt securities of such series. (See Section 1006.)

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Consolidation, Merger and Conveyance of Assets as an Entirety; No Financial Covenants

We have agreed not to consolidate or merge with or into any other entity, or to sell, transfer, lease or otherwise convey our property and assets as an entirety or substantially as an entirety to any other entity, unless:

Neither the indenture nor the senior debt securities contain any financial or other similar restrictive covenants.

(See Section 801.)

Modification of Indenture

Without Registered Holder Consent

Without the consent of any registered holders of outstanding senior debt securities, we and the trustee may enter into one or more supplemental indentures for any of the following purposes:

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(See Section 901.)

With Registered Holder Consent

Subject to the following sentence, we and the trustee may, with some exceptions, amend or modify the indenture with the consent of the registered holders of a majority in principal amount of the senior debt securities of each series affected by the amendment or modification. However, no amendment or modification may, without the consent of the registered holder of each outstanding senior debt security affected thereby:

A supplemental indenture which changes or eliminates any covenant or other provision of the indenture expressly included solely for the benefit of holders of senior debt securities of one or more particular series will be deemed not to affect the rights under the indenture of the holders of senior debt securities of any other series.

(See Section 902.)

Defeasance

The indenture provides, unless the terms of the particular series of senior debt securities provide otherwise, that we may, upon satisfying several conditions, cause ourselves to be discharged from our obligations, with some exceptions, with respect to any series of senior debt securities, which we refer to as "defeasance."

One condition we must satisfy is the irrevocable deposit with the trustee, in trust, of money and/or government obligations which, through the scheduled payment of principal and interest on those obligations, would provide sufficient moneys to pay the principal of and any premium and interest on the senior debt securities of the applicable series on the maturity dates of the payments or upon redemption.

In addition, we will be required to deliver an opinion of counsel to the effect that a holder of senior debt securities of the applicable series will not recognize income, gain or loss for federal income tax purposes as a result of the defeasance and will be subject to federal income tax on the same amounts, at the same times and in the same manner as if that defeasance had not occurred. The opinion of counsel must be based upon a ruling of the Internal Revenue Service or a change in law after the date of the indenture.

(See Article XIII.)

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Satisfaction and Discharge

The indenture will cease to be of further effect with respect to any series of senior debt securities, and we will be deemed to have satisfied and discharged all of our obligations under the indenture with respect to the senior debt securities of such series, except as noted below, when:

Notwithstanding the satisfaction and discharge of the indenture with respect to any series of senior debt securities, we will remain obligated to pay amounts due under certain provisions of the indenture and to perform certain ministerial tasks as described in the indenture.

(See Section 401.)

Resignation and Removal of the Trustee; Deemed Resignation

The trustee with respect to any series of senior debt securities may resign at any time by giving written notice to us. The trustee may also be removed with respect to the senior debt securities of any series by the registered holders of a majority in principal amount of the outstanding senior debt securities of such series. No resignation or removal of the trustee and no appointment of a successor trustee will become effective until the acceptance of appointment by a successor trustee in accordance with the requirements of the indenture. (See Section 610.)

Miscellaneous Provisions

The indenture provides that certain senior debt securities, including those for which payment or redemption money has been deposited or set aside in trust as described under "-Satisfaction and Discharge" above, will not be deemed to be "outstanding" in determining whether the registered holders of the requisite principal amount of the outstanding senior debt securities have given or taken any demand, direction, consent or other action under the indenture as of any date. (See Section 101.)

We will be entitled to set any day as a record date for the purpose of determining the registered holders of outstanding senior debt securities of any series entitled to give or take any demand, direction, consent or other action under the indenture, in the manner and subject to the limitations provided in the indenture. In certain circumstances, the trustee also will be entitled to set a record date for action by registered holders of any series of outstanding senior debt securities. If a record date is set for any action to be taken by registered holders of particular senior debt securities, the action may be taken only by persons who are registered holders of the respective senior debt securities on the record date. (See Section 104.)

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Governing Law

The indenture and the senior debt securities will be governed by and construed in accordance with the laws of the State of New York, without regard to conflicts of laws principles thereof. (See Section 112.)

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DESCRIPTION OF SERIES PREFERRED STOCK

The following is a general description of some of the terms and provisions of the series preferred stock, without par value (the "series preferred stock"), that we may offer and sell under this prospectus and also describes certain general terms of our preferred stock, series A preferred stock and preference stock (as those terms are defined below) authorized by our restated articles of incorporation. To the extent the terms and provisions of any series of series preferred stock modify the general terms and provisions described below, such modifications will be described in a prospectus supplement or free writing prospectus relating to such series. Under this heading "Description of Series Preferred Stock," references to "we," "us," "our" and similar terms mean, unless otherwise specified or the context otherwise requires, Southern California Gas Company excluding its consolidated entities (if any).

The series preferred stock will be governed by our restated articles of incorporation and bylaws and applicable California law. Our restated articles of incorporation give us broad authority to set the particular terms of each series of series preferred stock. The particular terms of a series of series preferred stock will be described in the applicable prospectus supplement or a free writing prospectus, relating to such series of series preferred stock.

Our restated articles of incorporation and bylaws contain the full legal text of the matters described under this heading "Description of Series Preferred Stock." The following description of certain provisions of our restated articles of incorporation and bylaws is not complete and is qualified in its entirety by reference to all the provisions of our restated articles of incorporation, including the certificate of determination of preferences for any series of series preferred stock that may be issued and outstanding in the future, any bylaws, copies of which have been or will be filed or incorporated by reference as exhibits to the registration statement of which this prospectus is a part or to a document incorporated by reference in this prospectus and which may be obtained as described under "Where You Can Find More Information." Whenever we refer to particular sections or defined terms of our restated articles of incorporation, including any applicable certificate of determination of preferences, or bylaws in this prospectus or a prospectus supplement or free writing prospectus, those sections or defined terms are incorporated by reference in this prospectus or the applicable prospectus supplement or free writing prospectus. This description also is subject to and qualified by reference to the description of the particular terms of a particular series of series preferred stock described in the applicable prospectus supplement or free writing prospectus related to any offering of such series of series preferred stock.

General

We are currently authorized to issue (i) 100,000,000 shares of common stock, without par value (the "common stock"), of which 91,300,000 shares were outstanding as of April 20, 2026, (ii) 160,000 shares of preferred stock, par value $25 per share (the "preferred stock"), of which 79,011 shares were outstanding as of April 20, 2026, (iii) 840,000 shares of preferred stock, series A, par value $25 per share (the "series A preferred stock"), of which 783,032 shares were outstanding as of April 20, 2026, (iv) 5,000,000 shares of series preferred stock, without par value, none of which is outstanding, and (v) 5,000,000 shares of preference stock, without par value (the "preference stock"), none of which is outstanding. No other classes of capital stock are authorized under our restated articles of incorporation.

We may in the future amend our restated articles of incorporation to increase the authorized number of shares of our authorized common stock, preferred stock, series A preferred stock, series preferred stock or preference stock, or to authorize shares of one or more additional classes of stock. Any such amendment would require approval by our board of directors and approval by our shareholders.

Under this heading "Description of Series Preferred Stock," we refer to the preferred stock, series A preferred stock and series preferred stock currently authorized by our restated articles of incorporation as the "currently authorized preferred stock," and we refer to the preference stock currently authorized by our restated articles of incorporation as the "currently authorized preference stock."

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Series Preferred Stock and Preference Stock

The series preferred stock and preference stock is issuable in series. Subject to the maximum number of shares of series preferred stock and preference stock authorized by our restated articles of incorporation, our board of directors is authorized, without the need for a vote or other action of our shareholders, to cause the issuance of shares of our series preferred stock or preference stock from time to time in one or more series, to determine the number of shares and designation of the series preferred stock or preference stock of any series, to increase or decrease (but not below the number of shares of such series then outstanding) the number of shares of any such series subsequent to the issuance of shares of that series, and to determine or alter the rights, preferences, privileges and restrictions granted to or imposed upon any wholly unissued series of preferred stock, which may include, among other things, dividend and liquidation rights and preferences, including with respect to relative ranking; rights to convert such shares into common stock; any rights and terms of redemption, including sinking fund provisions; any voting rights in addition to those described below under "-Additional Terms Applicable to Currently Authorized Preferred Stock and Currently Authorized Preference Stock-Voting Rights"; and any other specific terms, preferences, rights, limitations or restrictions; in each case in accordance with our restated articles of incorporation. Accordingly, our board of directors could cause the issuance of one or more series of our series preferred stock ranking on parity with or senior to one or more other series of our series preferred stock (subject to the terms of any one or more other series of our series preferred stock, if any, then outstanding) with respect to dividends or distributions in the event of our liquidation, dissolution or winding up or with voting or other rights that could dilute or otherwise adversely affect any voting rights or the other rights and economic interests of the holders of any such other series of series preferred stock.

The currently authorized preferred stock and currently authorized preference stock, including any shares of series preferred stock that we may offer and sell pursuant to this prospectus, are subject to the terms and conditions set forth below under "-Additional Terms Applicable to Currently Authorized Preferred Stock and Currently Authorized Preference Stock."

In the event that we issue any series of series preferred stock pursuant to this prospectus, we will describe the terms of such series of series preferred stock in a prospectus supplement to this prospectus and, if applicable, a free writing prospectus.

Preferred Stock and Series A Preferred Stock

The preferred stock and series A preferred stock are not issuable in series and have the rights, preferences, privileges and restrictions set forth in our restated articles of incorporation, some of which are described below, and as may be provided by applicable law. Subject to the maximum number of shares of preferred stock and series A preferred stock authorized by our restated articles of incorporation, our board of directors is authorized, without the need for a vote or other action of our shareholders, to cause the issuance of shares of preferred stock and series A preferred stock from time to time.

Additional Terms Applicable to Currently Authorized Preferred Stock and Currently Authorized Preference Stock

Except as otherwise described below, the following provisions are applicable to all shares of currently authorized preferred stock and currently authorized preference stock.

Ranking

All shares of currently authorized preferred stock rank on parity with each other with respect to the payment of dividends and distributions in the event of our liquidation or dissolution. All shares of currently authorized preferred stock rank senior to currently authorized preference stock, and all shares of currently authorized preferred stock and currently authorized preference stock rank senior to our common stock, in each case with respect to the payment of dividends and with respect to distributions in the event of our liquidation or dissolution.

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Dividend Rights

The holders of currently authorized preferred stock are entitled, without preference as between any classes or series of currently authorized preferred stock, to receive, if, when and as declared by our board of directors, out of any legally available funds, dividends at the respective rates established for such classes and series before any dividends are declared and set apart for payment or paid on the currently authorized preference stock or our common stock. Dividends on the preferred stock and series A preferred stock are payable at the annual rate of 6% of the $25 par value thereof. Dividends on each series of series preferred stock will be payable at the rate established for such series. Dividends on currently authorized preferred stock are cumulative, so that if, for any period, the full amount of dividends is not declared and set apart for payment or paid on all outstanding shares of currently authorized preferred stock, the deficiency shall be payable subsequently before any dividend is declared and set apart for payment or paid on the currently authorized preference stock or our common stock.

The holders of currently authorized preference stock are entitled, without preference as between any series of currently authorized preference stock, to receive, if, when and as declared by our board of directors, out of any legally available funds, dividends at the respective rate established for such series before any dividends are declared and set apart for payment or paid on our common stock. Dividends on each series of currently authorized preference stock will be payable at the rate established for such series. Dividends on currently authorized preference stock are cumulative, so that if, for any period, the full amount of dividends is not declared and set apart for payment or paid on all outstanding shares of currently authorized preference stock, the deficiency shall be payable subsequently before any dividend is declared and set apart for payment or paid on our common stock.

Whenever all cumulative dividends on currently authorized preferred stock and currently authorized preference stock have been declared and set apart for payment or paid, our board of directors may declare dividends on our common stock payable out of remaining funds legally available for dividends.

Liquidation Rights

In the event of our liquidation or dissolution, the holders of currently authorized preferred stock would be entitled, without preference as between any classes or series of currently authorized preferred stock, to receive out of our assets available for distribution to shareholders and after payment of or provision for our debts and other liabilities, the respective liquidation preferences established for each such class and series and accrued and unpaid dividends thereon before any distribution of assets is made to the holders of the currently authorized preference stock or our common stock. The liquidation preference of our preferred stock and series A preferred stock is $25.00 per share. The liquidation preference of any series of series preferred stock will be as established for each such series. After payment in full of the respective amounts to which the holders of currently authorized preferred stock are entitled in the event of our liquidation or dissolution, the holders of currently authorized preference stock would be entitled, without preference as between any series of currently authorized preference stock, to receive out of our assets available for distribution to shareholders, the respective liquidation preferences established for each such series and accrued and unpaid dividends thereon before any distribution of assets is made to the holders of our common stock. The liquidation preference for any series of currently authorized preference stock will be as established for each such series. After payment in full of the respective amounts to which the holders of currently authorized preference stock are entitled in the event of our liquidation or dissolution, the holders of preferred stock (but not the series A preferred stock or any series of series preferred stock) and the holders of our common stock would be entitled to receive, pro rata, our remaining assets available for distribution to shareholders.

Voting Rights

The holders of currently authorized preferred stock, currently authorized preference stock and common stock are entitled to one vote for each share and all vote together in the election of directors and on all matters

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presented to shareholders, except those matters for which a vote by class or series is required by applicable law or, in the case of any series of series preferred stock or any series of preference stock, by the terms established for such series.

Other Rights

The preferred stock and the series A preferred stock do not contain any conversion rights or sinking fund or redemption provisions. Any series of series preferred stock or preference stock may be convertible, redeemable or have sinking fund provisions, if at all, upon the terms established for each such series. Holders of currently authorized preferred stock and currently authorized preference stock are not entitled to preemptive rights to subscribe for or purchase any part of any new or additional issue of stock or securities convertible into stock.

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GLOBAL SECURITIES

Under this heading "Global Securities," references to "we," "us," "our" and similar terms mean Southern California Gas Company excluding its consolidated entities (if any), and references to "securities" mean the first mortgage bonds and the senior debt securities offered under this prospectus and the applicable prospectus supplement or free writing prospectus.

Book-Entry, Delivery and Form

Unless we indicate differently in any applicable prospectus supplement or free writing prospectus, the securities initially will be issued in book-entry form and represented by one or more global first mortgage bonds or global senior debt securities, as applicable (collectively, "global securities"). The global securities will be deposited with, or on behalf of, DTC, as depositary (which we sometimes refer to as the "depositary"), and registered in the name of Cede & Co., the nominee of DTC. Unless and until it is exchanged for definitive securities in certificated form registered in the names of persons other than the depositary or its nominee, which we refer to as "certificated securities," under the limited circumstances described below, a global security may not be transferred except as a whole by the depositary to its nominee or by the nominee to the depositary, or by the depositary or its nominee to a successor depositary or to a nominee of the successor depositary.

DTC has advised us that it is:

DTC holds securities that its participants deposit with DTC. DTC also facilitates the settlement among its participants of securities transactions, such as transfers and pledges, in deposited securities through electronic computerized book-entry changes in participants' accounts, thereby eliminating the need for physical movement of securities certificates. "Direct participants" in DTC include securities brokers and dealers, including underwriters, banks, trust companies, clearing corporations and other organizations. Indirect access to the DTC system is also available to others, which we sometimes refer to as "indirect participants," that clear transactions through or maintain a custodial relationship with a direct participant either directly or indirectly. The rules applicable to DTC and its participants are on file with the SEC.

Purchases of securities under the DTC system must be made by or through direct participants, which will receive a credit for the securities on DTC's records. The ownership interest of the actual purchaser of a security, which we sometimes refer to as a "beneficial owner," is in turn recorded on the direct and indirect participants' records. Beneficial owners of securities will not receive written confirmation from DTC of their purchases. However, beneficial owners are expected to receive written confirmations providing details of their transactions, as well as periodic statements of their holdings, from the direct or indirect participants through which they purchased securities. Transfers of ownership interests in global securities are to be accomplished by entries made on the books of participants acting on behalf of beneficial owners. Beneficial owners will not receive certificates representing their ownership interests in the global securities, except under the limited circumstances described below.

To facilitate subsequent transfers, all global securities deposited by direct participants with DTC will be registered in the name of DTC's nominee, Cede & Co., or such other name as may be requested by an authorized representative of DTC. The deposit of securities with DTC and their registration in the name of Cede & Co. or

40

such other nominee will not change the beneficial ownership of the securities. DTC has no knowledge of the actual beneficial owners of the securities. DTC's records reflect only the identity of the direct participants to whose accounts the securities are credited, which may or may not be the beneficial owners. The participants are responsible for keeping account of their holdings on behalf of their customers.

So long as the securities are in book-entry form, you will receive payments and may transfer securities only through the facilities of the depositary and its direct and indirect participants.

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 legal requirements in effect from time to time.

Redemption notices will be sent to DTC. If less than all of the global securities of a particular series are being redeemed, DTC's practice is to determine by lot the amount of the beneficial interest of each direct participant in the global securities of such series to be redeemed.

In any case where a consent or vote may be required with respect to any securities, neither DTC nor Cede & Co. (or such other DTC nominee) will consent or vote with respect to the applicable global securities. Under its usual procedures, DTC will mail an omnibus proxy to us as soon as possible after the record date. The omnibus proxy assigns the consenting or voting rights of Cede & Co. (or such other DTC nominee) to those direct participants to whose accounts beneficial interests in such global securities are credited on the record date, identified in a listing attached to the omnibus proxy.

Principal, premium (if any) and interest payments on the global securities will be paid to DTC or its nominee, as the registered owner of such securities, by wire transfer of immediately available funds. DTC's practice is to credit direct participants' accounts upon DTC's receipt of funds from us on the payment date in accordance with their respective holdings shown on DTC 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 account of customers in bearer form or registered in "street name." Those payments will be the responsibility of participants and not of DTC or us, subject to any statutory or regulatory requirements in effect from time to time. Payment of the principal of, premium (if any) and interest on the global securities to Cede & Co., or such other nominee as may be requested by an authorized representative of DTC, is our responsibility, disbursement of payments to direct participants is the responsibility of DTC, and disbursement of payments to the beneficial owners is the responsibility of direct and indirect participants.

Except under the limited circumstances described below, purchasers of securities will not be entitled to have securities registered in their names and will not receive physical delivery of securities. Accordingly, each beneficial owner must rely on the procedures of DTC and its participants to exercise any rights under the securities and the applicable indenture.

The laws of some jurisdictions may require that some purchasers of offered securities take physical delivery of offered securities in definitive form. Those laws may impair the ability to transfer or pledge beneficial interests in securities.

As noted above, beneficial owners of a particular series of securities generally will not receive certificates representing their ownership interests in those securities. However, if:

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we will prepare and deliver certificated securities of such series in exchange for beneficial interests in the global securities. Any beneficial interest in a global security that is exchangeable under the circumstances described in the preceding sentence will be exchangeable for certificated securities of such series in definitive form registered in the names that the depositary directs. It is expected that these directions will be based upon directions received by the depositary from its participants with respect to ownership of beneficial interests in the global securities.

Euroclear and Clearstream

If so provided in the applicable prospectus supplement, you may hold interests in a global security through Clearstream Banking S.A., which we refer to as "Clearstream," or Euroclear Bank S.A./N.V., as operator of the Euroclear System, which we refer to as "Euroclear," either directly if you are a participant in Clearstream or Euroclear or indirectly through organizations which are participants in Clearstream or Euroclear. Clearstream and Euroclear will hold interests on behalf of their respective participants through customers' securities accounts in the names of Clearstream and Euroclear, respectively, on the books of their respective U.S. depositaries, which in turn will hold such interests in customers' securities accounts in such depositaries' names on DTC's books.

Clearstream and Euroclear are securities clearance systems in Europe. Clearstream and Euroclear hold securities for their respective participating organizations and facilitate the clearance and settlement of securities transactions between those participants through electronic book-entry changes in their accounts, thereby eliminating the need for physical movement of certificates.

Payments, deliveries, transfers, exchanges, notices and other matters relating to beneficial interests in global securities owned through Euroclear or Clearstream must comply with the rules and procedures of those systems. Transactions between participants in Euroclear or Clearstream, on one hand, and other participants in DTC, on the other hand, are also subject to DTC's rules and procedures.

Investors will be able to make and receive through Euroclear and Clearstream payments, deliveries, transfers and other transactions involving any beneficial interests in global securities held through those systems only on days when those systems are open for business. Those systems may not be open for business on days when banks, brokers and other institutions are open for business in the United States.

Cross-market transfers between participants in DTC, on the one hand, and participants in Euroclear or Clearstream, on the other hand, will be effected through DTC in accordance with the DTC's rules on behalf of Euroclear or Clearstream, as the case may be, by their respective U.S. depositaries; however, such cross-market transactions will require delivery of instructions to Euroclear or Clearstream, as the case may be, by the counterparty in such system in accordance with the rules and procedures and within the established deadlines (European time) of such system. Euroclear or Clearstream, as the case may be, will, if the transaction meets its settlement requirements, deliver instructions to its U.S. depositary to take action to effect final settlement on its behalf by delivering or receiving interests in the global securities through DTC, and making or receiving payment in accordance with normal procedures for same-day fund settlement. Participants in Euroclear or Clearstream may not deliver instructions directly to their respective U.S. depositaries.

Due to time zone differences, the securities accounts of a participant in Euroclear or Clearstream purchasing an interest in a global security from a direct participant in DTC will be credited, and any such crediting will be reported to the relevant participant in Euroclear or Clearstream, during the securities settlement processing day (which must be a business day for Euroclear or Clearstream) immediately following the settlement date of DTC.

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Cash received in Euroclear or Clearstream as a result of sales of interests in a global security by or through a participant in Euroclear or Clearstream to a direct participant in DTC will be received with value on the settlement date of DTC but will be available in the relevant Euroclear or Clearstream cash account only as of the business day for Euroclear or Clearstream following DTC's settlement date.

Other

The information under this heading "Global Securities" concerning DTC, Clearstream, Euroclear and their respective book-entry systems has been obtained from sources that we believe to be reliable, but we do not take responsibility for this information. This information has been provided solely as a matter of convenience. The rules and procedures of DTC, Clearstream and Euroclear are solely within the control of those organizations and could change at any time. Neither we nor the trustee nor any agent of ours or of the trustee, nor any broker, dealer, underwriter or agent of ours involved in the offer or sale of any securities, has any control over those entities and none of us or them takes any responsibility for their activities. You are urged to contact DTC, Clearstream and Euroclear or their respective participants directly to discuss those matters. In addition, although we expect that DTC, Clearstream and Euroclear will perform the foregoing procedures, none of them is under any obligation to perform or continue to perform such procedures and such procedures may be discontinued at any time. Neither we nor the trustee nor any agent of ours or of the trustee, nor any broker, dealer, underwriter or agent of ours involved in the offer or sale of any securities, will have any responsibility for the performance or nonperformance by DTC, Clearstream and Euroclear or their respective participants of these or any other rules or procedures governing their respective operations.

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PLAN OF DISTRIBUTION

We may sell the securities offered pursuant to this prospectus from time to time:

We will identify the specific plan of distribution, including any underwriters, dealers, agents or direct purchasers and their respective compensation, in the applicable prospectus supplement.

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LEGAL MATTERS

Latham & Watkins LLP will pass upon certain legal matters relating to the issuance and sale of the securities offered hereby on behalf of Southern California Gas Company. Additional legal matters may be passed upon for us or any underwriters, dealers or agents, by counsel that we will name in the applicable prospectus supplement.

EXPERTS

The financial statements incorporated by reference in this prospectus and the effectiveness of Southern California Gas Company's internal control over financial reporting, have been audited by Deloitte & Touche LLP, an independent registered public accounting firm, as stated in their reports. Such financial statements are incorporated in reliance upon the reports of such firm given upon their authority as experts in accounting and auditing.

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PART II.

INFORMATION NOT REQUIRED IN PROSPECTUS

The following is an estimate of the expenses (other than underwriting discounts and commissions), all of which are to be paid by the registrant, that may be incurred in connection with the securities being registered hereby.

Section 317 of the Corporations Code of the State of California permits a corporation to provide indemnification to its directors and officers under certain circumstances. The Southern California Gas Company Bylaws (as amended) provide for mandatory indemnification of directors and officers, subject to the limitations set forth therein. In addition, the Southern California Gas Company Restated Articles of Incorporation eliminate the liability of directors for monetary damages to the fullest extent permissible under California law and provide Southern California Gas Company with the power, by bylaw, agreement or otherwise, to provide for indemnification for liability for monetary damages incurred by directors and officers of Southern California Gas Company, subject to certain limitations, in excess of the indemnification otherwise permitted by Section 317 of the Corporations Code. Southern California Gas Company maintains liability insurance and is also insured against loss for which it may be required or permitted by law to indemnify its directors and officers for their related acts.

The directors and officers of Southern California Gas Company are covered by insurance policies indemnifying them against certain liabilities, including certain liabilities arising under the Securities Act, which might be incurred by them in such capacities and against which they cannot be indemnified by Southern California Gas Company.

Any underwriting agreement or distribution agreement that Southern California Gas Company enters into with any underwriters or agents involved in the offering or sale of any securities registered hereby may require such underwriters or dealers to indemnify Southern California Gas Company, some or all of its directors and officers and its controlling persons, if any, for specified liabilities, which may include liabilities under the Securities Act.

Insofar as indemnification for liabilities arising under the Securities Act may be permitted to directors, officers or persons controlling the registrant pursuant to the foregoing provisions, the registrant has been informed that in the opinion of the U.S. Securities and Exchange Commission such indemnification is against public policy as expressed in the Securities Act and is therefore unenforceable.

II-1

Exhibit Index

II-2

(a) The undersigned registrant hereby undertakes:

(1) To file, during any period in which offers or sales are being made, a post-effective amendment to this registration statement:

(i) To include any prospectus required by Section 10(a)(3) of the Securities Act of 1933;

(ii) To reflect in the prospectus any facts or events arising after the effective date of the registration statement (or the most recent post-effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in the registration statement. Notwithstanding the foregoing, any increase or decrease in volume of securities offered (if the total dollar value of securities offered would not exceed that which was registered) and any deviation from the low or high end of the estimated maximum offering range may be reflected in the form of prospectus filed with the U.S. Securities and Exchange Commission, or the "Commission," pursuant to Rule 424(b) if, in the aggregate, the changes in volume and price represent no more than 20 percent change in the maximum aggregate offering price set forth in the "Calculation of Registration Fee" table in the effective registration statement; and

(iii) To include any material information with respect to the plan of distribution not previously disclosed in the registration statement or any material change to such information in the registration statement;

provided, however, that paragraphs (a)(1)(i), (a)(1)(ii) and (a)(1)(iii) of this section do not apply if the information required to be included in a post-effective amendment by those paragraphs is contained in reports filed with or furnished to the Commission by the registrant pursuant to section 13 or section 15(d) of the Securities Exchange Act of 1934, as amended, that are incorporated by reference in the registration statement, or is contained in a form of prospectus filed pursuant to Rule 424(b) that is a part of the registration statement.

(2) That, for the purpose of determining any liability under the Securities Act of 1933, each such post-effective amendment shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

(3) To remove from registration by means of a post-effective amendment any of the securities being registered which remain unsold at the termination of the offering.

II-3

(5) That, for the purpose of determining liability under the Securities Act of 1933 to any purchaser:

(A) Each prospectus filed by the registrant pursuant to Rule 424(b)(3) shall be deemed to be part of the registration statement as of the date the filed prospectus was deemed part of and included in the registration statement; and

(B) Each prospectus required to be filed pursuant to Rule 424(b)(2), (b)(5), or (b)(7) as part of a registration statement in reliance on Rule 430B relating to an offering made pursuant to Rule 415(a)(1)(i), (vii), or (x) for the purpose of providing the information required by section 10(a) of the Securities Act of 1933 shall be deemed to be part of and included in the registration statement as of the earlier of the date such form of prospectus is first used after effectiveness or the date of the first contract of sale of securities in the offering described in the prospectus. As provided in Rule 430B, for liability purposes of the issuer and any person that is at that date an underwriter, such date shall be deemed to be a new effective date of the registration statement relating to the securities in the registration statement to which that prospectus relates, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof. Provided, however, that no statement made in a registration statement or prospectus that is part of the registration statement or made in a document incorporated or deemed incorporated by reference into the registration statement or prospectus that is part of the registration statement will, as to a purchaser with a time of contract of sale prior to such effective date, supersede or modify any statement that was made in the registration statement or prospectus that was part of the registration statement or made in any such document immediately prior to such effective date.

(6) That, for the purpose of determining liability of the registrant under the Securities Act of 1933 to any purchaser in the initial distribution of the securities:

The undersigned registrant undertakes that in a primary offering of securities of the undersigned registrant pursuant to this registration statement, regardless of the underwriting method used to sell the securities to the purchaser, if the securities are offered or sold to such purchaser by means of any of the following communications, the undersigned registrant will be a seller to the purchaser and will be considered to offer or sell such securities to such purchaser:

(i) Any preliminary prospectus or prospectus of the undersigned registrant relating to the offering required to be filed pursuant to Rule 424;

(ii) Any free writing prospectus relating to the offering prepared by or on behalf of the undersigned registrant or used or referred to by the undersigned registrant;

(iii) The portion of any other free writing prospectus relating to the offering containing material information about the undersigned registrant or its securities provided by or on behalf of the undersigned registrant; and

(iv) Any other communication that is an offer in the offering made by the undersigned registrant to the purchaser.

(b) The undersigned registrant hereby undertakes that, for purposes of determining any liability under the Securities Act of 1933, each filing of the registrant's annual report pursuant to Section 13(a) or Section 15(d) of the Securities Exchange Act of 1934 (and, where applicable, each filing of an employee benefit plan's annual report pursuant to Section 15(d) of the Securities Exchange Act of 1934) that is incorporated by reference in the registration statement shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

(h) Insofar as indemnification for liabilities arising under the Securities Act of 1933 may be permitted to directors, officers and controlling persons of the registrant pursuant to the foregoing provisions, or otherwise, the registrant has been advised that, in the opinion of the Commission such indemnification is against public policy as expressed in the Securities Act and is, therefore, unenforceable. In the event that a claim for indemnification

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against such liabilities (other than the payment by the registrant of expenses incurred or paid by a director, officer or controlling person of the registrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the registrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Securities Act and will be governed by the final adjudication of such issue.

(j) The undersigned registrant hereby undertakes to file an application for the purpose of determining the eligibility of the trustee to act under subsection (a) of Section 310 of the Trust Indenture Act ("Act") in accordance with the rules and regulations prescribed by the Commission under section 305(b)(2) of the Act.

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SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, as amended, the registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-3 and has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Los Angeles, State of California, on April 21, 2026.

POWER OF ATTORNEY

Each of the undersigned officers and directors of the registrant hereby severally constitutes and appoints each individual who, at the time of acting under this power of attorney, is the Chief Executive Officer, the President, the Chief Operating Officer, the Principal Financial Officer (however designated), the Principal Accounting Officer (however designated), an Executive Vice President, a Senior Vice President, the Controller, an Assistant Controller, the Treasurer or an Assistant Treasurer of Southern California Gas Company, and each of them singly (with full power to each of them to act alone), as his or her true and lawful attorneys-in-fact and agents, with full power of substitution and resubstitution in each of them, for him or her and in his or her name, place and stead, and in any and all capacities, to sign any and all amendments to this registration statement, including post-effective amendments, and any registration statement for the same offering that is to be effective under Rule 462(b) of the Securities Act of 1933, as amended, and to file the same, with all exhibits thereto and other documents in connection therewith, with the U.S. Securities and Exchange Commission, granting unto said attorneys-in-fact and agents, and each of them, full power and authority to do and perform each and every act and thing requisite and necessary to be done in connection therewith as fully to all intents and purposes as he or she might or could do in person, hereby ratifying and confirming all that said attorneys-in-fact and agents, or their substitute or substitutes may lawfully do or cause to be done by virtue hereof. This power of attorney shall be governed by and construed in accordance with the laws of the State of California and applicable federal securities laws.

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

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