Form of Supplemental Indenture No. 23, to be dated as of February 23, 2023, to the Indenture between CenterPoint Energy Resources Corp. and The Bank of New York Mellon Trust Company, N.A., as trustee

CENTERPOINT ENERGY RESOURCES CORP.

SUPPLEMENTAL INDENTURE NO. 23

5.25% Senior Notes due 2028

5.40% Senior Notes due 2033

SUPPLEMENTAL INDENTURE No. 23, dated as of February 23, 2023, between CENTERPOINT ENERGY RESOURCES CORP., a Delaware corporation formerly known as NorAm Energy Corp. (the “Company”), and THE BANK OF NEW YORK MELLON TRUST COMPANY, N.A. (successor to JPMorgan Chase Bank, National Association (formerly Chase Bank of Texas, National Association)), as Trustee (the “Trustee”).

RECITALS

The Company has heretofore executed and delivered to the Trustee an Indenture, dated as of February 1, 1998 (the “Original Indenture” and, as previously and hereby supplemented and amended, the “Indenture”), providing for the issuance from time to time of one or more series of the Company’s Securities.

The Company has changed its name from “NorAm Energy Corp.” to “CenterPoint Energy Resources Corp.” and all references in the Indenture to the “Company” or “NorAm Energy Corp.” shall be deemed to refer to CenterPoint Energy Resources Corp.

Pursuant to the terms of the Indenture, the Company desires to provide for the establishment of two new series of Securities to be designated as the “5.25% Senior Notes due 2028” (the “2028 Notes”) and the “5.40% Senior Notes due 2033” (the “2033 Notes” and, together with the 2028 Notes, the “Notes”), the form and substance of such Notes and the terms, provisions and conditions thereof to be set forth as provided in the Original Indenture and this Supplemental Indenture No. 23.

Section 301 of the Original Indenture provides that various matters with respect to any series of Securities issued under the Indenture may be established in an indenture supplemental to the Indenture.

Subparagraph (7) of Section 901 of the Original Indenture provides that the Company and the Trustee may enter into an indenture supplemental to the Indenture to establish the form or terms of Securities of any series as permitted by Sections 201 and 301 of the Original Indenture.

For and in consideration of the premises and the issuance of the series of Securities provided for herein, it is mutually covenanted and agreed, for the equal and proportionate benefit of the Holders of the Securities of such series, as follows:

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ARTICLE ONE

Relation to Indenture; Additional Definitions

Section 101 Relation to Indenture. This Supplemental Indenture No. 23 constitutes an integral part of the Original Indenture.

Section 102 Additional Definitions. For all purposes of this Supplemental Indenture No. 23:

Capitalized terms used but not defined in this Supplement Indenture No. 23 have the meaning given such terms in the Original Indenture. Capitalized terms defined in both this Supplemental Indenture No. 23 and in the Original Indenture have the meaning given such terms in this Supplemental Indenture No. 23.

“2028 Notes” has the meaning set forth in the third paragraph of the Recitals hereof.

“2033 Notes” has the meaning set forth in the third paragraph of the Recitals hereof.

“2028 Notes Maturity Date” has the meaning set forth in Section 203 hereof.

“2033 Notes Maturity Date” has the meaning set forth in Section 203 hereof.

“2028 Notes Par Call Date” has the meaning set forth in Section 401 hereof.

“2033 Notes Par Call Date” has the meaning set forth in Section 401 hereof.

“Authorized Officers” has the meaning set forth in Section 606 hereof.

“Business Day” means, with respect to any Note, any day other than a Saturday, a Sunday or a day on which banking institutions or trust companies in The City of New York are generally authorized or required by law or executive order to remain closed. If any Interest Payment Date, Stated Maturity or Redemption Date of a Note falls on a day that is not a Business Day, the required payment will be made on the next succeeding Business Day with the same force and effect as if made on the relevant date that the payment was due and no interest will accrue on such payment for the period from and after the Interest Payment Date, Stated Maturity or Redemption Date, as the case may be, to the date of that payment on the next succeeding Business Day.

“Consolidated Net Tangible Assets” means the total amount of assets of the Company, including the assets of its Subsidiaries, less, without duplication: (a) total current liabilities (excluding indebtedness due within 12 months); (b) all reserves for depreciation and other asset valuation reserves, but excluding reserves for deferred federal income taxes; (c) all intangible assets such as goodwill, trademarks, trade names, patents and unamortized debt discount and expense carried as an asset; and (d) all appropriate adjustments on account of minority interests of other Persons holding common stock of any Subsidiary, all as reflected in the Company’s most recent audited consolidated balance sheet preceding the date of such determination.

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“control” (including the terms “controlled by” and “under common control with”) means the possession, direct or indirect, of the power to direct or cause the direction of the management and policies of a Person, whether through the ownership of voting shares, by contract, or otherwise.

“Corporate Trust Office” means the principal office of the Trustee at which at any particular time its corporate trust business shall be administered, which office as of the date hereof is located at: 601 Travis Street, 16th Floor, Houston, Texas 77002, Attention: Global Corporate Trust; telephone: (713) 483-6817; telecopy: (713) 483-7038.

“Electronic Means” means the following communications methods: e-mail, facsimile transmission, secure electronic transmission containing applicable authorization codes, passwords and/or authentication keys issued by the Trustee, or another method or system specified by the Trustee as available for use in connection with its services hereunder.

“Equity Interests” means any capital stock, partnership, joint venture, member or limited liability or unlimited liability company interest, beneficial interest in a trust or similar entity or other equity interest or investment of whatever nature.

“H.15” has the meaning set forth in Section 402 hereof.

“H.15 TCM” has the meaning set forth in Section 402 hereof.

“Finance Lease” means a lease that, in accordance with accounting principles generally accepted in the United States of America, would be recorded as a finance lease on the balance sheet of the lessee, but excluding, for the avoidance of doubt, any operating leases or any other non-finance leases.

“indebtedness” means, as applied to the Company or any Subsidiary, means bonds, debentures, notes and other instruments or arrangements representing obligations created or assumed by the Company or any such Subsidiary, including any and all: (i) obligations for money borrowed (other than unamortized debt discount or premium); (ii) obligations evidenced by a note or similar instrument given in connection with the acquisition of any business, properties or assets of any kind; (iii) obligations as lessee under a Finance Lease; and (iv) amendments, renewals, extensions, modifications and refundings of any such indebtedness or obligation listed in clause (i), (ii) or (iii) above. All indebtedness secured by a lien upon property owned by the Company or any Subsidiary and upon which indebtedness the Company or any such Subsidiary customarily pays interest, although the Company or any such Subsidiary has not assumed or become liable for the payment of such indebtedness, shall for all purposes hereof be deemed to be indebtedness of the Company or any such Subsidiary. All indebtedness for borrowed money incurred by other Persons which is directly guaranteed as to payment of principal by the Company or any

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Subsidiary shall for all purposes hereof be deemed to be indebtedness of the Company or any such Subsidiary, as applicable, but no other contingent obligation of the Company or any such Subsidiary in respect of indebtedness incurred by other Persons shall for any purpose be deemed to be indebtedness of the Company or any such Subsidiary.

“Instructions” has the meaning set forth in Section 606 hereof.

“Interest Payment Date” has the meaning set forth in Section 204(a) hereof.

“Issue Date” has the meaning set forth in Section 204(a) hereof.

“Lien” means any mortgage, deed of trust, pledge, hypothecation, assignment, deposit arrangement, charge, security interest, encumbrance or lien of any kind whatsoever (including any Finance Lease).

“Maturity Date” has the meaning set forth in Section 203 hereof.

“Non-Recourse Debt” means (i) any indebtedness for borrowed money incurred by any Project Finance Subsidiary to finance the acquisition, improvement, installation, design, engineering, construction, development, completion, maintenance or operation of, or otherwise to pay costs and expenses relating to or providing financing for, any project, which indebtedness for borrowed money does not provide for recourse against the Company or any Subsidiary of the Company (other than a Project Finance Subsidiary and such recourse as exists under a Performance Guaranty) or any property or asset of the Company or any Subsidiary of the Company (other than Equity Interests in, or the property or assets of, a Project Finance Subsidiary and such recourse as exists under a Performance Guaranty) and (ii) any refinancing of such indebtedness for borrowed money that does not increase the outstanding principal amount thereof (other than to pay costs incurred in connection therewith and the capitalization of any interest or fees) at the time of the refinancing or increase the property subject to any lien securing such indebtedness for borrowed money or otherwise add additional security or support for such indebtedness for borrowed money.

“Notes” has the meaning set forth in the third paragraph of the Recitals hereof.

“Original Indenture” has the meaning set forth in the first paragraph of the Recitals hereof.

“Par Call Date” has the meaning set forth in Section 401 hereof.

“Performance Guaranty” means any guaranty issued in connection with any Non-Recourse Debt that (i) if secured, is secured only by assets of or Equity Interests in a Project Finance Subsidiary, and (ii) guarantees to the provider of such Non-Recourse Debt or any other person (a) performance of the improvement, installation, design, engineering, construction, acquisition, development, completion, maintenance or operation of, or otherwise affects any such act in respect of, all or any portion of the project that is financed by such Non-Recourse Debt, (b) completion of the minimum agreed equity or other contributions or support to the relevant Project Finance Subsidiary, or (c) performance by a Project Finance Subsidiary of obligations to persons other than the provider of such Non-Recourse Debt.

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“Project Finance Subsidiary” means any Subsidiary designated by the Company whose principal purpose is to incur Non-Recourse Debt and/or construct, lease, own or operate the assets financed thereby, or to become a direct or indirect partner, member or other equity participant or owner in a Person created for such purpose, and substantially all the assets of which Subsidiary or Person are limited to (x) those assets being financed (or to be financed), or the operation of which is being financed (or to be financed), in whole or in part by Non-Recourse Debt, or (y) Equity Interests in, or indebtedness or other obligations of, one or more other such Subsidiaries or Persons, or (z) indebtedness or other obligations of the Company or any Subsidiary or other Persons. At the time of designation of any Project Finance Subsidiary, the sum of the net book value of the assets of such Subsidiary and the net book value of the assets of all other Project Finance Subsidiaries then existing shall not in the aggregate exceed 10 percent of the Consolidated Net Tangible Assets.

“Regular Record Date” has the meaning set forth in Section 204(a) hereof.

“Remaining Life” has the meaning set forth in Section 402 hereof.

“Subsidiary” of any entity means any corporation, partnership, joint venture, limited liability company, trust or estate of which (or in which) more than 50% of (i) the issued and outstanding capital stock having ordinary voting power to elect a majority of the Board of Directors of such corporation (irrespective of whether at the time capital stock of any other class or classes of such corporation shall or might have voting power upon the occurrence of any contingency), (ii) the interest in the capital or profits of such limited liability company, partnership, joint venture or other entity or (iii) the beneficial interest in such trust or estate is at the time directly or indirectly owned or controlled by such entity, by such entity and one or more of its other subsidiaries or by one or more of such entity’s other subsidiaries.

“Treasury Rate” has the meaning set forth in Section 402 hereof.

All references herein to Articles and Sections, unless otherwise specified, refer to the corresponding Articles and Sections of this Supplemental Indenture No. 23.

The terms “herein,” “hereof,” “hereunder” and other words of similar import refer to this Supplemental Indenture No. 23.

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ARTICLE TWO

The Series of Securities

Section 201 Title of the Securities. The 2028 Notes shall be designated as the “5.25% Senior Notes due 2028” and the 2033 Notes shall be designated as the “5.40% Senior Notes due 2033.”

Section 202 Limitation on Aggregate Principal Amount. The Trustee shall authenticate and deliver (i) the 2028 Notes for original issue on the Issue Date in the aggregate principal amount of $600,000,000 and (ii) the 2033 Notes for original issue on the Issue Date in the aggregate principal amount of $600,000,000, upon a Company Order for the authentication and delivery thereof and satisfaction of Sections 301 and 303 of the Original Indenture. Such order shall specify the amount of the Notes to be authenticated, the date on which the original issue of Notes is to be authenticated and the name or names of the initial Holder or Holders. The aggregate principal amount of the 2028 Notes and 2033 Notes that may initially be outstanding shall not exceed $600,000,000 and $600,000,000, respectively; provided, however, that the authorized aggregate principal amount of either series of the Notes may be increased above such amount by a Board Resolution to such effect.

Section 203 Stated Maturity. The Stated Maturity of the 2028 Notes shall be March 1, 2028 (the “2028 Notes Maturity Date”), and the Stated Maturity of the 2033 Notes shall be March 1, 2033 (the “2033 Notes Maturity Date”).

Section 204 Interest and Interest Rates.

(a) The 2028 Notes shall bear interest at a rate of 5.25% per year, from and including February 23, 2023 (the “Issue Date”) to, but excluding, the 2028 Notes Maturity Date. The 2033 Notes shall bear interest at a rate of 5.40% per year, from and including the Issue Date to, but excluding, the 2033 Notes Maturity Date. Such interest shall be payable semi-annually in arrears on March 1 and September 1 of each year (each an “Interest Payment Date”), beginning September 1, 2023, to the persons in whose names the Notes (or one or more Predecessor Securities) are registered at the close of business on February 15 and August 15 (each a “Regular Record Date”) (whether or not a Business Day), as the case may be, immediately preceding such Interest Payment Date.

(b) Any such interest not so punctually paid or duly provided for shall forthwith cease to be payable to the Holder on such Regular Record Date and shall either (i) be paid to the Person in whose name such Note (or one or more Predecessor Securities) is registered at the close of business on the Special Record Date for the payment of such Defaulted Interest to be fixed by the Trustee, notice whereof shall be given to Holders of such Notes not less than 10 days prior to such Special Record Date, or (ii) be paid at any time in any other lawful manner not inconsistent with the requirements of any securities exchange or automated quotation system on which such Notes may be listed or traded, and upon such notice as may be required by such exchange or automated quotation system, all as more fully provided in the Indenture.

(c) The amount of interest payable for any period shall be computed on the basis of a 360-day year of twelve 30-day months. The amount of interest payable for any partial period shall be computed on the basis of a 360-day year of twelve 30-day months and the days elapsed in any partial month. In the event that any date on which interest is payable on a Note is not a Business Day, then a payment of the interest payable on such date will be made on the next succeeding day which is a Business Day (and without any interest or other payment in respect of any such delay) with the same force and effect as if made on the date the payment was originally payable.

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(d) Any principal and premium, if any, and any installment of interest, which is overdue shall bear interest at the rate of 5.25% per annum (to the extent permitted by law), in the case of the 2028 Notes, or 5.40% per annum (to the extent permitted by law), in the case of the 2033 Notes, in each case from the dates such amounts are due until they are paid or made available for payment, and such interest shall be payable on demand.

Section 205 Paying Agent; Place of Payment. The Trustee shall initially serve as the Paying Agent for the Notes. The Company may appoint and change any Paying Agent or approve a change in the office through which any Paying Agent acts without notice, other than notice to the Trustee. The Company or any of its Subsidiaries or any of their Affiliates may act as Paying Agent. The Place of Payment where the Notes may be presented or surrendered for payment shall be the Corporate Trust Office of the Trustee. At the option of the Company, payment of interest may be made (i) by check mailed to the address of the Person entitled thereto as such address shall appear in the Security Register or (ii) by wire transfer in immediately available funds at such place and to such account as may be designated in writing by the Person entitled thereto as specified in the Security Register.

Section 206 Place of Registration or Exchange; Notices and Demands With Respect to the Notes. The place where the Holders of the Notes may present the Notes for registration of transfer or exchange and may make notices and demands to or upon the Company in respect of the Notes shall be the Corporate Trust Office of the Trustee.

Section 207 Percentage of Principal Amount. The 2028 Notes and 2033 Notes shall be initially issued at 99.680% and 99.975% of their principal amount, respectively, plus accrued interest, if any, from the Issue Date.

Section 208 Global Securities. The Notes shall be issuable in whole or in part in the form of one or more Global Securities. Such Global Securities shall be deposited with, or on behalf of, The Depository Trust Company, New York, New York, which shall act as Depositary with respect to the Notes. Such Global Securities shall bear the legends set forth in the forms of Security attached as Exhibit A and Exhibit B hereto.

Section 209 Form of Securities. The 2028 Notes shall be substantially in the form attached as Exhibit A hereto and the 2033 Notes shall be substantially in the form attached as Exhibit B hereto.

Section 210 Securities Registrar. The Trustee shall initially serve as the Security Registrar for the Notes.

Section 211 Defeasance and Discharge; Covenant Defeasance.

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(a) Article Fourteen of the Original Indenture, including without limitation Sections 1402 and 1403 thereof (as modified by Section 211(b) hereof), shall apply to each series of the Notes.

(b) Solely with respect to each series of the Notes issued hereby, the first sentence of Section 1403 of the Original Indenture is hereby deleted in its entirety, and the following is substituted in lieu thereof:

“Upon the Company’s exercise of its option (if any) to have this Section 1403 applied to any Securities or any series of Securities, as the case may be, (1) the Company shall be released from its obligations under Article Eight and under any covenants provided pursuant to Section 301(20), 901(2) or 901(7) for the benefit of the Holders of such Securities, including without limitation, the covenants provided for in Article Three of Supplemental Indenture No. 23 to the Indenture, and (2) the occurrence of any event specified in Sections 501(4) (with respect to Article Eight and to any such covenants provided pursuant to Section 301(20), 901(2) or 901(7)) and 501(7) shall be deemed not to be or result in an Event of Default, in each case with respect to such Securities as provided in this Section 1403 on and after the date the conditions set forth in Section 1404 are satisfied (hereinafter called “Covenant Defeasance”).”

Section 212 Sinking Fund Obligations. The Company shall have no obligation to redeem or purchase any Notes pursuant to any sinking fund or analogous requirement or upon the happening of a specified event or at the option of a Holder thereof.

ARTICLE THREE

Additional Covenants

Section 301. Maintenance of Properties. The Company shall cause all properties used or useful in the conduct of its business or the business of any Subsidiary to be maintained and kept in good condition, repair and working order and supplied with all necessary equipment and shall cause to be made all necessary repairs, renewals, replacements, betterments and improvements thereof, all as in the judgment of the Company may be necessary so that the business carried on in connection therewith may be properly conducted at all times; provided, however, that nothing in this Section 301 shall prevent the Company from discontinuing the operation or maintenance of any of such properties if such discontinuance is, in the judgment of the Company, desirable in the conduct of its business or the business of any Subsidiary.

Section 302. Payment of Taxes and Other Claims. The Company shall pay or discharge or cause to be paid or discharged, before the same shall become delinquent, (1) all taxes, assessments and governmental charges levied or imposed upon the Company or any Subsidiary or upon the income, profits or property of the Company or any Subsidiary, and (2) all lawful claims for labor, materials and supplies which, if unpaid, might by law become a lien upon the property of the Company or any Subsidiary; provided, however, that the Company shall not be required to pay or discharge or cause to be paid or discharged any such tax, assessment, charge or claim whose amount, applicability or validity is being contested in good faith by appropriate proceedings.

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ARTICLE FOUR

Optional Redemption of the Notes

Section 401 Redemption Price.

(a) Prior to February 1, 2028, in the case of the 2028 Notes (the “2028 Notes Par Call Date”), or December 1, 2032, in the case of the 2033 Notes (the “2033 Notes Par Call Date”; each of the 2028 Notes Par Call Date and the 2033 Notes Par Call Date, a “Par Call Date”), the Company may redeem the 2028 Notes or the 2033 Notes, respectively, at its option, in whole or in part, at any time and from time to time, at a redemption price (expressed as a percentage of principal amount and rounded to three decimal places) equal to the greater of (1)(a) the sum of the present values of the remaining scheduled payments of principal and interest on the Notes of such series to be redeemed discounted to the Redemption Date (assuming the Notes to be redeemed matured on the applicable Par Call Date) on a semi-annual basis (assuming a 360-day year consisting of twelve 30-day months) at the applicable Treasury Rate plus 20 basis points for the 2028 Notes or 25 basis points for the 2033 Notes less (b) interest accrued to the date of redemption, and (2) 100% of the principal amount of the Notes to be redeemed, plus, in each case, accrued and unpaid interest thereon, if any, to, but excluding, the Redemption Date.

(b) On or after the 2028 Notes Par Call Date, in the case of the 2028 Notes, or the 2033 Notes Par Call Date, in the case of the 2033 Notes, the Company may redeem, at its option, the 2028 Notes or the 2033 Notes, respectively, in whole or in part, at any time or from time to time, at a redemption price equal to 100% of the principal amount of the Notes to be redeemed plus accrued and unpaid interest on the principal amount being redeemed, if any, to, but excluding, the Redemption Date.

Section 402 Calculation.

“Treasury Rate” means, with respect to any Redemption Date, the yield determined by the Company in accordance with the following two paragraphs.

The Treasury Rate shall be determined by the Company after 4:15 p.m., New York City time (or after such time as yields on U.S. government securities are posted daily by the Board of Governors of the Federal Reserve System), on the third Business Day preceding the Redemption Date based upon the yield or yields for the most recent day that appear after such time on such day in the most recent statistical release published by the Board of Governors of the Federal Reserve System designated as “Selected Interest Rates (Daily)—H.15” (or any successor designation or publication) (“H.15”) under the caption “U.S. government securities–Treasury constant maturities–Nominal” (or any successor caption or heading) (“H.15 TCM”). In determining the Treasury Rate, the Company shall select, as applicable: (1) the yield for the Treasury constant maturity on H.15 exactly equal to the period from the Redemption Date to the applicable Par Call Date (the “Remaining Life”); or (2) if there is no such Treasury constant maturity on H.15 exactly

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equal to the Remaining Life, the two yields – one yield corresponding to the Treasury constant maturity on H.15 immediately shorter than and one yield corresponding to the Treasury constant maturity on H.15 immediately longer than the Remaining Life – and shall interpolate to the applicable Par Call Date on a straight-line basis (using the actual number of days) using such yields and rounding the result to three decimal places; or (3) if there is no such Treasury constant maturity on H.15 shorter than or longer than the Remaining Life, the yield for the single Treasury constant maturity on H.15 closest to the Remaining Life. For purposes of this paragraph, the applicable Treasury constant maturity or maturities on H.15 shall be deemed to have a maturity date equal to the relevant number of months or years, as applicable, of such Treasury constant maturity from the applicable Redemption Date.

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

The Company’s actions and determinations in determining the redemption price shall be conclusive and binding for all purposes, absent manifest error. The Trustee shall have no responsibility for the calculation of such amount.

Section 403 Partial Redemption. If fewer than all of the Notes of a series are to be redeemed by the Company pursuant to this Article Four, not more than 60 days prior to the Redemption Date, the particular Notes or portions thereof called for redemption will be selected from the outstanding Notes of such series not previously called by lot by the Trustee. The Trustee may select for redemption Notes and portions of Notes in amounts of $2,000 or whole multiples of $1,000. A new Note in principal amount equal to the unredeemed portion of the original Note shall be issued upon the cancellation of the original Note. In the case of a partial redemption of Notes of a series registered in the name of Cede & Co., the Notes to be redeemed will be determined in accordance with the procedures of The Depository Trust Company.

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Section 404 Notice of Optional Redemption.

(a) The Trustee, at the written direction of the Company, will send a notice of redemption by first-class mail (or otherwise transmitted in accordance with the procedures of The Depository Trust Company with respect to Notes registered in the name of Cede & Co.) at least 10 days and not more than 60 days prior to the date fixed for redemption to each holder of Notes to be redeemed. Unless the Company defaults on payment of the redemption price, interest will cease to accrue on the Notes or portions thereof called for redemption on the Redemption Date. If any Note is to be redeemed in part only, the notice of redemption shall state the portion of the principal amount to be redeemed.

(b) Notice of any redemption of Notes may, at the Company’s discretion, be given subject to one or more conditions precedent, including, but not limited to, completion of a corporate transaction that is pending (such as an equity or equity-linked offering, an incurrence of indebtedness or an acquisition or other strategic transaction involving a change of control in the Company or another Person). If such redemption is so subject to satisfaction of one or more conditions precedent, such notice shall describe each such condition, and such notice may be rescinded in the event that any or all such conditions shall not have been satisfied or otherwise waived on or prior to the Business Day immediately preceding the relevant redemption date. The Company shall notify holders of Notes of any such rescission as soon as practicable after it determines that such conditions precedent will not be able to be satisfied or the Company is not able or willing to waive such conditions precedent.

ARTICLE FIVE

Remedies

Section 501 Additional Event of Default; Acceleration of Maturity.

(a) Solely with respect to the Notes of each series issued hereby, Section 501(7) of the Original Indenture is hereby deleted in its entirety, and the following is substituted in lieu thereof as an Event of Default in addition to the other events set forth in Section 501 of the Original Indenture:

“(7) the default by the Company or any Subsidiary, other than a Project Finance Subsidiary, in the payment, when due, after the expiration of any applicable grace period, of principal of indebtedness for money borrowed, other than Non-Recourse Debt, in the aggregate principal amount then outstanding of $125 million or more, or acceleration of any indebtedness for money borrowed in such aggregate principal amount so that it becomes due and payable prior to the date on which it would otherwise have become due and payable and such acceleration is not rescinded or such default is not cured within 30 days after there has been given, by registered or certified mail, to the Company by the Trustee or to the Company and the Trustee by the holders of at least 33% in principal amount of the Notes of such series Outstanding written notice specifying such default and requiring the Company to cause such acceleration to be rescinded or such default to be cured and stating that such notice is a “Notice of Default” under the Indenture;”.

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(b) Solely with respect to the Notes of each series issued hereby, the first paragraph of Section 502 of the Original Indenture is hereby deleted in its entirety, and the following is substituted in lieu thereof:

“If an Event of Default (other than an Event of Default specified in Section 501(5) or 501(6)) with respect to the Notes of either series at the time Outstanding occurs and is continuing, then in every such case the Trustee or the Holders of not less than 33% in principal amount of the Notes of such series Outstanding may declare the principal amount of all the Notes of such series to be due and payable immediately, by a notice in writing to the Company (and to the Trustee if given by Holders), and upon any such declaration such principal amount (or specified amount) shall become immediately due and payable. If an Event of Default specified in Section 501(5) or 501(6) with respect to the Notes of such series at the time Outstanding occurs and is continuing, the principal amount of all the Notes of such series shall automatically, and without any declaration or other action on the part of the Trustee or any Holder, become immediately due and payable.”

Section 502 Amendment of Certain Provisions. Solely with respect to the Notes of each series issued hereby, references to “25%” in Article Five of the Indenture are hereby deleted in their entirety and “33%” is substituted in lieu thereof.

ARTICLE SIX

Miscellaneous Provisions

Section 601 The Indenture, as supplemented and amended by this Supplemental Indenture No. 23, is in all respects hereby adopted, ratified and confirmed.

Section 602 This Supplemental Indenture No. 23 may be executed in any number of counterparts, each of which shall be an original, but such counterparts shall together constitute but one and the same instrument. The words “execution,” “executed,” “signed,” signature,” and words of like import in this Supplemental Indenture No. 23 shall include images of manually executed signatures transmitted by facsimile, email or other electronic format (including, without limitation, “pdf,” “tif” or “jpg”) and other electronic signatures (including, without limitation, DocuSign and AdobeSign). The use of electronic signatures and electronic records (including, without limitation, any contract or other record created, generated, sent, communicated, received, or stored by electronic means) shall be of the same legal effect, validity and enforceability as a manually executed signature or use of a paper-based record-keeping system to the fullest extent

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permitted by applicable law, including the Federal Electronic Signatures in Global and National Commerce Act, the New York State Electronic Signatures and Records Act and any other applicable law, including, without limitation, any state law based on the Uniform Electronic Transactions Act or the Uniform Commercial Code. Without limitation to the foregoing, and anything in this Supplemental Indenture No. 23 to the contrary notwithstanding, (a) any Officers’ Certificate, Company Order, Opinion of Counsel, Security, certificate of authentication appearing on or attached to any Security or other certificate, Opinion of Counsel, instrument, agreement or other document delivered pursuant to this Supplemental Indenture No. 23 may be executed, attested and transmitted by any of the foregoing electronic means and formats, (b) all references in Section 303 or elsewhere in the Indenture to the execution, attestation or authentication of any Security or any certificate of authentication appearing on or attached to any Security by means of a manual or facsimile signature shall be deemed to include signatures that are made or transmitted by any of the foregoing electronic means or formats, and (c) any requirement in Section 303 or elsewhere in the Indenture that any signature be made under a corporate seal (or facsimile thereof) shall not be applicable to the Securities of such series.

Section 603 THIS SUPPLEMENTAL INDENTURE NO. 23 AND EACH NOTE SHALL BE DEEMED TO BE A CONTRACT MADE UNDER THE LAWS OF THE STATE OF NEW YORK AND SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK.

Section 604 If any provision in this Supplemental Indenture No. 23 limits, qualifies or conflicts with another provision hereof which is required to be included herein by any provisions of the Trust Indenture Act, such required provision shall control.

Section 605 In case any provision in this Supplemental Indenture No. 23 or the Notes shall be invalid, illegal or unenforceable, the validity, legality and enforceability of the remaining provisions shall not in any way be affected or impaired thereby.

Section 606 The Trustee shall have the right to accept and act upon instructions, including funds transfer instructions (“Instructions”) given pursuant to this Indenture and delivered using Electronic Means; provided, however, that the Company shall provide to the Trustee an incumbency certificate listing officers with the authority to provide such Instructions (“Authorized Officers”) and containing specimen signatures of such Authorized Officers, which incumbency certificate shall be amended by the Company whenever a person is to be added or deleted from the listing. If the Company elects to give the Trustee Instructions using Electronic Means and the Trustee in its discretion elects to act upon such Instructions, the Trustee’s understanding of such Instructions shall be deemed controlling. The Company understands and agrees that the Trustee cannot determine the identity of the actual sender of such Instructions and that the Trustee shall conclusively presume that directions that purport to have been sent by an Authorized Officer listed on the incumbency certificate provided to the Trustee have been sent by such Authorized Officer, unless the Trustee has knowledge to the contrary or the Trustee is acting in bad faith. The Company shall be responsible for ensuring that only Authorized Officers transmit such Instructions to the Trustee and that the Company and all Authorized Officers are solely responsible to safeguard the use and confidentiality of applicable user and authorization codes, passwords and/or authentication keys upon receipt by the Company. Absent gross negligence, willful

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misconduct or bad faith by the Trustee, the Trustee shall not be liable for any losses, costs or expenses arising directly or indirectly from the Trustee’s reliance upon and compliance with such Instructions notwithstanding such directions conflict or are inconsistent with a subsequent written instruction. The Company agrees, absent gross negligence, willful misconduct or bad faith by the Trustee: (i) to assume all risks arising out of the use of Electronic Means to submit Instructions to the Trustee, including the risk of the Trustee acting on unauthorized Instructions and the risk of interception and misuse by third parties; (ii) that it is fully informed of the protections and risks associated with the various methods of transmitting Instructions to the Trustee and that there may be more secure methods of transmitting Instructions than the method(s) selected by the Company; (iii) that the security procedures (if any) to be followed in connection with its transmission of Instructions provide to it a commercially reasonable degree of protection in light of its particular needs and circumstances; and (iv) to notify the Trustee as soon as practicable upon learning of any compromise or unauthorized use of the security procedures.

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IN WITNESS WHEREOF, the parties hereto have caused this Supplemental Indenture No. 23 to be duly executed, as of the day and year first written above.

Attest:

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Exhibit A

[FORM OF FACE OF SECURITY]

[IF THIS SECURITY IS TO BE A GLOBAL SECURITY -] THIS SECURITY IS A GLOBAL SECURITY WITHIN THE MEANING OF THE INDENTURE HEREINAFTER REFERRED TO AND IS REGISTERED IN THE NAME OF A DEPOSITARY OR A NOMINEE OF A DEPOSITARY. THIS SECURITY IS EXCHANGEABLE FOR SECURITIES REGISTERED IN THE NAME OF A PERSON OTHER THAN THE DEPOSITARY OR ITS NOMINEE ONLY IN THE LIMITED CIRCUMSTANCES DESCRIBED IN THE INDENTURE AND MAY NOT BE TRANSFERRED EXCEPT AS A WHOLE BY THE DEPOSITARY TO A NOMINEE OF THE DEPOSITARY OR BY A NOMINEE OF THE DEPOSITARY TO THE DEPOSITARY OR ANOTHER NOMINEE OF THE DEPOSITARY.

[FOR AS LONG AS THIS GLOBAL SECURITY IS DEPOSITED WITH OR ON BEHALF OF THE DEPOSITORY TRUST COMPANY IT SHALL BEAR THE FOLLOWING LEGEND.] UNLESS THIS CERTIFICATE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY, A NEW YORK CORPORATION (“DTC”), TO CENTERPOINT ENERGY RESOURCES CORP. OR ITS AGENT FOR REGISTRATION OF TRANSFER, EXCHANGE, OR PAYMENT, AND ANY CERTIFICATE ISSUED IS REGISTERED IN THE NAME OF CEDE & CO. OR IN SUCH OTHER NAME AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC (AND ANY PAYMENT IS MADE TO CEDE & CO. OR TO SUCH OTHER ENTITY AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC), ANY TRANSFER, PLEDGE, OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL INASMUCH AS THE REGISTERED OWNER HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.

CENTERPOINT ENERGY RESOURCES CORP.

5.25% Senior Notes due 2028

This Security is not an Original Issue Discount Security

within the meaning of the within-mentioned Indenture.