8-K - CEG - Equibles

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
FORM	8-K
CURRENT REPORT
Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934
January 15, 2026
Date of Report (Date of earliest event reported)			Commission<br>File Number	Name of Registrant; State or Other Jurisdiction of Incorporation; Address of Principal Executive Offices; and Telephone Number	IRS Employer Identification Number
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001-41137	CONSTELLATION ENERGY CORPORATION	87-1210716
	(a Pennsylvania corporation)<br><br>1310 Point Street<br><br>Baltimore, Maryland 21231-3380<br><br>(833) 883-0162
333-85496	CONSTELLATION ENERGY GENERATION, LLC	23-3064219
	(a Pennsylvania limited liability company)<br><br>200 Energy Way<br><br>Kennett Square, Pennsylvania 19348-2473<br><br>(833) 883-0162			Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:
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☐	Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)
☐	Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)
☐	Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))
☐	Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))		Securities registered pursuant to Section 12(b) of the Act:
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Title of each class	Trading Symbol(s)	Name of each exchange on which registered
CONSTELLATION ENERGY CORPORATION:
Common Stock, without par value	CEG	The Nasdaq Stock Market LLC		Indicate by check mark whether any of the registrants are emerging growth companies as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter). Emerging growth company ☐
---		If an emerging growth company, indicate by check mark if any of the registrants have elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐
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Section 1 - Registrant’s Business and Operations

Item 1.01. Entry into a Material Definitive Agreement

Exchange Offers and Consent Solicitation

As previously announced, on January 7, 2026, Constellation Energy Corporation (Nasdaq: CEG), a Pennsylvania corporation (“CEG Parent”) and Constellation Energy Generation, LLC, a Pennsylvania limited liability company (“Constellation”), completed the previously announced transactions contemplated by the Agreement and Plan of Merger, dated January 10, 2025 (the “Merger Agreement”), by and among CEG Parent, Calpine Corporation, a Delaware corporation (“Calpine”), CPN CS Holdco Corp., a Delaware corporation and wholly owned subsidiary of Calpine (“New Company”), CPN CKS Corp., a Delaware corporation and wholly owned subsidiary of New Company (“Company Merger Sub”), Cascade Transco Inc., a Delaware corporation and an indirect, wholly owned subsidiary of CEG Parent (“First Merger Sub”), Cascade Transco – 1, LLC, a Delaware limited liability company and an indirect, wholly owned subsidiary of CEG Parent (“Second Merger Sub”), and Volt Energy Holdings GP, LLC, a Delaware limited liability company, solely in its capacity as the representative of the stockholders of Calpine. Capitalized terms used but not defined herein have the meanings ascribed to them in the Merger Agreement. As a result of the transactions contemplated by the Merger Agreement, Calpine became a wholly owned subsidiary of Constellation.

Upon closing, Calpine (as a wholly owned subsidiary of Constellation) remained the issuer of (i) $650 million in aggregate principal amount of 4.625% Senior Notes due 2029 (the “2029 Senior Notes”); (ii) $850 million in aggregate principal amount of 5.000% Senior Notes due 2031 (the “2031 Senior Notes”) and (iii) $900 million in aggregate principal amount of 3.750% Senior Secured Notes due 2031 (the “2031 Senior Secured Notes” and, together with the 2029 Senior Notes and the 2031 Senior Notes, the “Calpine Notes”). On January 15, 2026 (the “Settlement Date”), Constellation completed its previously announced private offers to exchange any and all of the outstanding Calpine Notes for, to the extent held by eligible holders, newly issued (i) 4.625% Senior Notes due 2029 (“New 2029 Senior Notes”), (ii) 5.000% Senior Notes due 2031 (“New February 2031 Senior Notes”) and (iii) 3.750% Senior Notes due 2031 (“New March 2031 Senior Notes,” and, together with the New 2029 Senior Notes and the New February 2031 Senior Notes, the “Constellation Notes”) by Constellation having the same interest payment dates, maturity dates and interest rates as the Calpine Notes (each, an “Exchange Offer”, and collectively, the “Exchange Offers”). In connection with the Exchange Offers, Constellation also solicited consents (the “Consent Solicitations”) on behalf of Calpine from eligible holders to amend the Calpine Notes and the related indentures under which they were issued (the “Calpine Indentures”) to eliminate substantially all of the restrictive covenants, restrictive provisions and events of default, other than payment-related and bankruptcy-related events of default (the “Proposed Amendments”).

Pursuant to the Exchange Offers and Consent Solicitations, $2,289,722,000 aggregate principal amount of Calpine Notes were validly tendered and subsequently accepted. Such accepted Calpine Notes have been retired and canceled and will not be reissued.

The Exchange Offers have expired, and are no longer open to participation by any eligible holders of the Calpine Notes.

Following receipt of the requisite number of consents to adopt the Proposed Amendments with respect to the Calpine Notes and the Calpine Indentures, on the Settlement Date, Calpine entered into supplemental indentures with the trustee for the Calpine Notes to effect the Proposed Amendments. Reference is made to the supplemental indentures attached to this report as Exhibit 4.1, Exhibit 4.2 and Exhibit 4.3.

Constellation Notes

The Constellation Notes were issued under an indenture, dated as of September 28, 2007, between Constellation and U.S. Bank Trust Company, National Association, as trustee.

The New 2029 Senior Notes will bear interest at the rate of 4.625% per year. The New February 2031 Senior Notes will bear interest at the rate of 5.000% per year. The New March 2031 Senior Notes will bear interest at the rate of 3.750% per year.

Interest on the New 2029 Senior Notes and New February 2031 Senior Notes is payable on February 1 and August 1 of each year, beginning on February 1, 2026. Interest on the New March 31 Senior Notes is payable on March 1 and September 1 of each year, beginning on March 1, 2026.

The New 2029 Senior Notes will mature on February 1, 2029. The New February 2031 Senior Notes will mature on February 1, 2031. The New March 2031 Senior Notes will mature on March 1, 2031.

The Constellation Notes are subject to optional redemption as provided in the New 2029 Senior Notes, the New February 2031 Senior Notes and the New March 2031 Senior Notes.

Reference is made to the Form of New 2029 Senior Note attached as Exhibit 4.4, the Form of New February 2031 Senior Note attached as Exhibit 4.5 and the Form of New March 2031 Senior Note attached as Exhibit 4.6 for additional covenants, events of default and other terms and conditions of the Senior Notes.

Section 2 – Financial Information

Item 2.03(a). Creation of a Direct Financial Obligation

The information set forth in Item 1.01 of this Current Report on Form 8-K is hereby incorporated by reference into this Item 2.03.

Section 9 - Financial Statements and Exhibits

Item 9.01. Financial Statements and Exhibits

(d) Exhibits.

Exhibit No.	Description
4.1	First Supplemental Indenture, dated as of January 15, 2026, among Calpine Corporation and Wilmington Trust, National Association, as trustee.
4.2	First Supplemental Indenture, dated as of January 15, 2026, among Calpine Corporation and Wilmington Trust, National Association, as trustee.
4.3	Second Supplemental Indenture, dated as of January 15, 2026, among Calpine Corporation, the guarantors party thereto and Wilmington Trust, National Association, as trustee.
4.4	Form of New 2029 Senior Note.
4.5	Form of New February 2031 Senior Note.
4.6	Form of New March 2031 Senior Note .
101	Cover Page Interactive Data File - the cover page XBRL tags are embedded within the Inline XBRL document.
104	The cover page from this Current Report on Form 8-K, formatted as Inline XBRL.

* * * * *

This combined Current Report on Form 8-K is being furnished separately by Constellation Energy Corporation and Constellation Energy Generation, LLC, (collectively, the “Registrants”). Information contained herein relating to one of the Registrants has been furnished by such Registrant on its own behalf. Neither Registrant makes any representation as to information relating to the other Registrant.

This Current Report on Form 8-K contains certain forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995 that are subject to risks and uncertainties. Words such as “could,” “may,” “expects,” “anticipates,” “will,” “targets,” “goals,” “projects,” “intends,” “plans,” “believes,” “seeks,” “estimates,” “predicts,” and variations on such words, and similar expressions that reflect the Registrants’ current views with respect to future events and operational, economic, and financial performance, are intended to identify such forward-looking statements. These forward-looking statements include, but are not limited to, statements regarding the exchange offers, the consent solicitations, the expected timing and likelihood of completion of the exchange offers and consent solicitations, the pro forma combined company and its operations, strategies, plans, synergies, opportunities and anticipated future performance and capital structure. Information adjusted for the acquisition of Calpine Corporation should not be considered a forecast of future results. Although the Registrants believe these forward-looking statements are reasonable, statements made regarding future results are not guarantees of future performance and are subject to numerous assumptions, uncertainties and risks that are difficult to predict. Forward-looking statements are based on current expectations, estimates and assumptions that involve a number of risks and uncertainties that could cause actual results to differ materially from those projected.

Actual outcomes and results may differ materially from the results stated or implied in the forward-looking statements included in this Current Report on Form 8-K due to a number of factors, including, but not limited to the risk that problems may arise in successfully integrating the businesses of the companies, which may result in the combined company not operating as effectively and efficiently as expected, and the risk that the combined company may be unable to achieve synergies or other anticipated benefits of the acquisition of Calpine Corporation or it may take longer than expected to achieve those synergies or benefits. Other unpredictable or unknown factors not discussed in this Current Report on Form 8-K could also have material adverse effects on forward-looking statements.

The factors that could cause actual results to differ materially from the forward-looking statements made by the Registrants include those factors discussed herein, as well as the items discussed in (1) the Registrants’ 2024 Annual Report on Form 10-K in (a) Part I, ITEM 1A. Risk Factors, (b) Part II, ITEM 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations, and (c) Part II, ITEM 8. Financial Statements and Supplementary Data: Note 18, Commitments and Contingencies; (2) the Registrants’ Third Quarter 2025 Quarterly Report on Form 10-Q in (a) Part II, ITEM 1A. Risk Factors, (b) Part I, ITEM 2. Management’s Discussion and Analysis of Financial Condition and Results of Operations, and (c) Part I, ITEM 1. Financial Statements: Note 14, Commitments and Contingencies; and (3) other factors discussed in filings with the Securities and Exchange Commission by the Registrants.

Investors are cautioned not to place undue reliance on these forward-looking statements, whether written or oral, which apply only as of the date of this Current Report on Form 8-K. Neither Registrant undertakes any obligation to publicly release any revision to its forward-looking statements to reflect events or circumstances after the date of this Current Report on Form 8-K.

SIGNATURES

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

CONSTELLATION ENERGY CORPORATION
/s/ Shane P. Smith
Shane P. Smith
Executive Vice President and Chief Financial Officer
Constellation Energy Corporation
CONSTELLATION ENERGY GENERATION, LLC
/s/ Shane P. Smith
Shane P. Smith
Executive Vice President and Chief Financial Officer
Constellation Energy Generation, LLC

January 15, 2026

EXHIBIT INDEX

Exhibit No.	Description
4.1	First Supplemental Indenture, dated as of January 15, 2026, among Calpine Corporation and Wilmington Trust, National Association, as trustee.
4.2	First Supplemental Indenture, dated as of January 15, 2026, among Calpine Corporation and Wilmington Trust, National Association, as trustee.
4.3	Second Supplemental Indenture, dated as of January 15, 2026, among Calpine Corporation, the guarantors party thereto and Wilmington Trust, National Association, as trustee.
4.4	Form of New 2029 Senior Note.
4.5	Form of New February 2031 Senior Note.
4.6	Form of New March 2031 Senior Note .
101	Cover Page Interactive Data File - the cover page XBRL tags are embedded within the Inline XBRL document.
104	The cover page from this Current Report on Form 8-K, formatted as Inline XBRL.

ceg-202601158kexh41

#4899-0636-3271 v2 FIRST SUPPLEMENTAL INDENTURE between CALPINE LLC and WILMINGTON TRUST, NATIONAL ASSOCIATION, as Trustee Dated as of January 15, 2026 Supplementing and Amending the Indenture Dated as of August 10, 2020

This First Supplemental Indenture is dated as of January 15, 2026 (this “Supplement”), and is between Calpine LLC, a Delaware limited liability company (formerly Calpine Corporation, a Delaware corporation) (the “Company”), and Wilmington Trust, National Association, as trustee (the “Trustee”), and supplements and amends the Indenture, dated as of August 10, 2020 (as previously supplemented, the “Existing Indenture”), between the Company and the Trustee. WHEREAS, pursuant to the Existing Indenture, the Company issued its 4.625% Senior Notes due 2029 (the “Notes”); WHEREAS, pursuant to Section 9.02 (With Consent of Holders) of the Existing Indenture, the Company and the Trustee may amend or supplement the Existing Indenture and the Notes with the consent of the Holders of a majority in aggregate principal amount of the then outstanding Notes (including, without limitation, Additional Notes, if any) voting as a single class (including, without limitation, consents obtained in connection with a tender offer or exchange offer for, or purchase of, the Notes), and, subject to Sections 6.04 (Waiver of Past Defaults) and 6.07 (Rights of Holders to Receive Payment) of the Existing Indenture, any existing Default or Event of Default (other than a Default or Event of Default in the payment of the principal of, premium, if any, or interest on, the Notes, except a payment default resulting from an acceleration that has been rescinded) or compliance with any provision of the Existing Indenture or the Notes may be waived with the consent of the Holders of a majority in aggregate principal amount of the then outstanding Notes (including, without limitation, Additional Notes, if any) voting as a single class (including, without limitation, consents obtained in connection with a tender offer or exchange offer for, or purchase of, the Notes); and WHEREAS, all acts and things necessary to constitute this Supplement a valid indenture and agreement according to its terms have been done and performed, including the requisite consent of the Holders of a majority in aggregate principal amount of the then outstanding Notes, and the Company and the Trustee have duly authorized the execution and delivery of this Supplement and the amended and restated Notes. NOW, THEREFORE, the parties hereby agree as follows: Section 1. Definitions. Each capitalized term used but not otherwise defined herein has the meaning given to it in the Existing Indenture. Section 2. Amendments to Existing Indenture. From and after the date hereof: The Existing Indenture is hereby amended by deleting all references to “Calpine Corporation” therein and replacing them with “Calpine LLC”. The Existing Indenture is hereby amended by deleting all references to “a Delaware corporation” therein and replacing them with “a Delaware limited liability company”. Section 1.02 (Other Definitions) of the Existing Indenture is hereby amended by deleting the definitions of “Change of Control Offer”, “Change of Control Payment” and “Change of Control Payment Date”. Sections 4.03 (Reports), 4.04 (Compliance Certificate), 4.05 (Taxes), 4.06 (Stay, Extension and Usury Laws), 4.07 (Liens), 4.08 (Corporate Existence), 4.09 (Offer to Repurchase Upon Change of Control Triggering Event), and 5.01 (Merger, Consolidation, or Sale of Assets) of the Existing Indenture are each hereby deleted in their entirety and replaced as follows:

-2- “Section 4.03 Reserved” “Section 4.04 Reserved” “Section 4.05 Reserved” “Section 4.06 Reserved” “Section 4.07 Reserved” “Section 4.08 Reserved” “Section 4.09 Reserved” “Section 5.01 Reserved” provided further that, the Table of Contents set forth in the Existing Indenture shall be updated accordingly. Section 5.02 (Successor Corporation Substituted) of the Existing Indenture is hereby amended by deleting “in a transaction that is subject to, and that complies with the provisions of, Section 5.01 hereof” and “; provided, however, that the predecessor Company shall not be relieved from the obligation to pay the principal of and interest on the Notes except in the case of a sale of all of the Company’s assets in a transaction that is subject to, and that complies with the provisions of, Section 5.01 hereof” from such section. Clauses (3) and (4) of Section 6.01 (Events of Default) of the Existing Indenture are each hereby deleted in their entirety. The last sentence of Section 8.03 (Covenant Defeasance) of the Existing Indenture is hereby deleted in its entirety. Clause (2) of Section 9.02 (With Consent of Holders) of the Existing Indenture is hereby amended by deleting the following from such clause: “other than provisions relating to Section 4.09 hereof and”. Clause (7) of Section 9.02 (With Consent of Holders) of the Existing Indenture is hereby amended by deleting “(other than a payment required by Section 4.09 hereof)” from such clause. Section 3. Waiver. Subject to Section 6.04 (Waiver of Past Defaults) and Section 6.07 (Rights of Holders to Receive Payment) of the Existing Indenture, the Holders hereby waive (i) any existing Default or Event of Default and its consequences under the Existing Indenture and/or (ii) any current or future Default or Event of Default and its consequences under the Existing Indenture, in each case relating to the provisions of the Existing Indenture that have been deleted pursuant to this Supplement. Section 4. Authorization of Amended and Restated Notes. Upon the execution and delivery of this Supplement, the outstanding Notes shall each be, or be deemed to be, amended and restated substantially in the form attached to this Supplement as Exhibit A. Section 5. Notices. Pursuant to Section 11.01 (Notices) of the Existing Indenture, the Company hereby designates the following addresses for subsequent notices and communications:

-3- Calpine LLC c/o Constellation Energy Generation, LLC 200 Energy Way Kennett Square, PA, 19348-2473 Attention: Legal Department Email: legalnotices@constellation.com Telephone: (833) 883-0162 with a copy to (which shall not constitute notice): Ballard Spahr LLP Attention: Patrick R. Gillard, Esq. Telephone: (215) 864-8536 Email: gillard@ballardspahr.com Section 6. Execution and Authentication. Upon delivery of an executed copy of this Supplement, executed copies of an Officer’s Certificate and an Opinion of Counsel required by Section 9.05 (Trustee to Sign Amendments, etc.) of the Existing Indenture and an authentication and cancellation order, the Company may deliver amended and restated Notes to the Trustee for authentication as provided for in the Existing Indenture. Section 7. Ratification of Existing Indenture. As supplemented and amended hereby, the Existing Indenture is hereby, in all respects, ratified and confirmed and the Existing Indenture, as supplemented and amended hereby, shall be read, taken and construed as one and the same instrument. Section 8. Severability. If any provision of this Supplement shall be held invalid by any court of competent jurisdiction, such holding shall not invalidate any other provision hereof. Section 9. Counterparts. This Supplement may be executed in several counterparts, each of which together shall be an original and all of which shall constitute one instrument. Section 10. Governing Law. THE INTERNAL LAW OF THE STATE OF NEW YORK WILL GOVERN AND BE USED TO CONSTRUE THIS SUPPLEMENT AND THE NOTES WITHOUT GIVING EFFECT TO APPLICABLE PRINCIPLES OF CONFLICTS OF LAW TO THE EXTENT THAT THE APPLICATION OF THE LAWS OF ANOTHER JURISDICTION WOULD BE REQUIRED THEREBY. Section 11. The Trustee. The Trustee makes no representation or warranty as to the validity or sufficiency of this Supplement or with respect to the recitals contained herein, all of which recitals are made solely by the other parties hereto. To the extent that the requisite consents to any amendment effected by this Supplement are determined by a court of competent jurisdiction to have not been validly obtained in accordance with the Existing Indenture or applicable laws, such amendment shall not be deemed to have occurred. Section 12. Electronic Signatures. The parties may sign any number of copies of this Supplement. Signatures to this Supplement or any instrument, agreement or document necessary for the consummation of the transactions contemplated by this Supplement or related hereto or thereto (including, without limitation, addendums, amendments, notices, instructions, communications with respect to the delivery of securities or the wire transfer of funds or other communications) (“Executed Documentation”) may be manual, facsimile, or Electronic Signatures. Each signed copy shall be an original, but all of them together represent the same agreement. Delivery of an executed counterpart of a signature page to this

-4- Supplement and other Executed Documentation by telecopier, facsimile or other electronic transmission (e.g. a “pdf” or “tif”) shall be effective as delivery of a manually executed counterpart thereof. The exchange of copies of this Supplement and other Executed Documentation and of signature pages by telecopier, facsimile or other electronic transmission (e.g. a “pdf” or “tif”) shall constitute effective execution and delivery of this Supplement and other Executed Documentation as to the parties hereto and may be used in lieu of the original Supplement or other Executed Documentation and signature pages for all purposes. “Electronic Signatures” means any electronic signatures covered by the Electronic Signatures in Global and National Commerce Act of 2000, Uniform Electronic Transactions Act, the Electronic Signatures and Records Act or other applicable law (e.g., www.docusign.com). [Remainder of Page Intentionally Left Blank]

IN WITNESS WHEREOF, the Company and the Trustee have caused this Supplement to be executed and delivered by duly authorized officers thereof as of the day and year first written above. CALPINE LLC, a Delaware limited liability company By: Name: Eugene P. Miles Title: Assistant Treasurer

WILMINGTON TRUST, NATIONAL ASSOCIATION, as Trustee By: Name: Title:

A-1 EXHIBIT A FORM OF AMENDED AND RESTATED NOTES [Face of Note] [Insert the Global Note Legend, if applicable pursuant to the provisions of the Indenture] [Insert the Private Placement Legend, if applicable pursuant to the provisions of the Indenture] CUSIP/ISIN ____________ [RULE 144A][REGULATION S][GLOBAL] NOTE 4.625% Senior Notes due 2029 No. ___ $___________ CALPINE LLC promises to pay to or registered assigns, the principal sum of DOLLARS on February 1, 2029. Interest Payment Dates: February 1 and August 1 Record Dates: January 15 and July 15 [Signature Page Follows]

A-2 IN WITNESS HEREOF, the Company has caused this Note to be signed manually or by facsimile by its duly authorized officer as of the date first written above. CALPINE LLC By: Name: Title: This is one of the Notes referred to in the within-mentioned Indenture: Dated: ______________ , ____ WILMINGTON TRUST, NATIONAL ASSOCIATION, as Trustee By: Authorized Signatory

A-3 [Back of Note] 4.625% Senior Notes due 2029 Capitalized terms used herein have the meanings assigned to them in the Indenture referred to below unless otherwise indicated. (1) INTEREST. Calpine LLC, a Delaware limited liability company (formerly Calpine Corporation, a Delaware corporation) (the “Company”), promises to pay interest on the principal amount of this Note at 4.625% per annum from August 10, 2020 1 until maturity. The Company will pay interest semi-annually in arrears on February 1 and August 1 of each year (each, an “Interest Payment Date”), or if any such day is not a Business Day, on the next succeeding Business Day. Interest on the Notes will accrue from the most recent Interest Payment Date to which interest has been paid or, if no interest has been paid, from the date of issuance; provided that if there is no existing Default in the payment of interest, and if this Note is authenticated between a record date referred to on the face hereof and the next succeeding Interest Payment Date, interest shall accrue from such next succeeding Interest Payment Date; provided further that the first Interest Payment Date shall be February 1, 2021 2 . Interest will be computed on the basis of a 360- day year of twelve 30-day months. (2) METHOD OF PAYMENT. The Company will pay interest on the Notes (except defaulted interest) to the Persons who are registered Holders at the close of business on January 15 or July 15 next preceding the Interest Payment Date, even if such Notes are canceled after such record date and on or before such Interest Payment Date, except as provided in Section 2.12 of the Indenture with respect to defaulted interest. The Notes will be payable as to principal, premium, if any, and interest at the office or agency of the Company maintained for such purpose or, at the option of the Company, payment of interest may be made by check mailed to the Holders at their addresses set forth in the register of Holders; provided that payment by wire transfer of immediately available funds will be required with respect to principal of and interest, premium on, all Global Notes and all other Notes the Holders of which will have provided wire transfer instructions to the Company or the Paying Agent. Such payment will be in such coin or currency of the United States of America as at the time of payment is legal tender for payment of public and private debts. (3) PAYING AGENT AND REGISTRAR. Initially, Wilmington Trust, National Association, the Trustee under the Indenture, will act as Paying Agent and Registrar. The Company may change any Paying Agent or Registrar without notice to any Holder. The Company or any of its Subsidiaries may act in any such capacity. (4) INDENTURE. The Company issued the Notes under an Indenture dated as of August 10, 2020 (as amended or supplemented from time to time, including as of January [ ], 2026, the “Indenture”) among the Company and the Trustee. The Notes are subject to all such terms, and Holders are referred to the Indenture for a statement of such terms. To the extent any provision of this Note conflicts with the express provisions of the Indenture, the provisions of the Indenture shall govern and be controlling. The Notes are unsecured obligations of the Company. The indenture does not limit the aggregate principal amount of Notes that may be issued thereunder. (5) OPTIONAL REDEMPTION. (a) On or after February 1, 2024, the Company may on any one or more occasions redeem all or a part of the Notes, upon not less than 30 nor more than 60 days’ notice, at the redemption prices 1 With respect to the Initial Notes. 2 With respect to the Initial Notes.

A-4 (expressed as percentages of principal amount) set forth below, plus accrued and unpaid interest, if any, on the Notes redeemed, to but excluding the applicable date of redemption, if redeemed during the twelve- month period beginning on February 1 of the years indicated below, subject to the rights of Holders on the relevant record date to receive interest on the relevant interest payment date: Year Percentage 2024 ............................................................................................................ 102.313% 2025 ............................................................................................................ 101.156% 2026 and thereafter ..................................................................................... 100.000% Unless the Company defaults in the payment of the redemption price, interest will cease to accrue on the Notes or portions thereof called for redemption on the applicable redemption date. (b) At any time prior to February 1, 2024, the Company may on any one or more occasions redeem up to 35% of the aggregate principal amount of Notes issued under the Indenture, upon not less than 30 nor more than 60 days’ notice, at a redemption price equal to 104.625% of the principal amount of the Notes redeemed, plus accrued and unpaid interest, if any, to but excluding the date of redemption (subject to the rights of Holders on the relevant record date to receive interest on the relevant interest payment date), with the proceeds of one or more Equity Offerings; provided that: (i) at least 65% of the aggregate principal amount of Notes originally issued under the Indenture (excluding Notes held by the Company and its Subsidiaries) remains outstanding immediately after the occurrence of such redemption; and (ii) the redemption occurs within 90 days of the date of the closing of such Equity Offering. (c) At any time prior to February 1, 2024, the Company may on any one or more occasions redeem all or a part of the Notes, upon not less than 30 nor more than 60 days’ notice, at a redemption price equal to 100% of the principal amount of the Notes redeemed, plus the Applicable Premium as of, and accrued and unpaid interest, if any, to but excluding the date of redemption, subject to the rights of Holders on the relevant record date to receive interest due on the relevant interest payment date. (d) At any time, in connection with any tender offer for the Notes, if Holders of not less than 90% in aggregate principal amount of the outstanding Notes validly tender and do not withdraw such Notes in such tender offer and the Company, or any third party making such tender offer in lieu of the Company, purchases all of the Notes validly tendered and not withdrawn by such Holders, the Company may, upon not less than 10 nor more than 60 days’ prior notice, given not more than 30 days following such purchase date, redeem all Notes that remain outstanding following such purchase at a redemption price equal to the price paid to each other Holder in such tender offer plus, to the extent not included in the tender offer payment, accrued and unpaid interest, if any, thereon, to, but not excluding, the date of such redemption (subject to the rights of Holders on the relevant record date to receive interest on the relevant interest payment date). (6) MANDATORY REDEMPTION. The Company is not required to make mandatory redemption or sinking fund payments with respect to the Notes. (7) RESERVED. (8) NOTICE OF REDEMPTION. Notice of redemption will be mailed or delivered electronically at least 30 days but not more than 60 days before the redemption date to each Holder whose Notes are to be redeemed at its registered address, except that (i) redemption notices may be mailed or delivered electronically at least 10 days prior to the redemption date if the notice is issued in connection

A-5 with a redemption pursuant to Section 3.07(c) of the Indenture and (ii) redemption notices may be mailed or delivered electronically more than 60 days prior to a redemption date if the notice is issued in connection with a defeasance of the Notes or a satisfaction or discharge of the Indenture. Notes in denominations larger than $2,000 may be redeemed in part but only in whole multiples of $1,000, unless all of the Notes held by a Holder are to be redeemed. Any redemption notice may, in the Company’s discretion, be subject to the satisfaction of one or more conditions precedent. If such redemption is subject to the satisfaction of one of more conditions precedent, such notice shall state that, in the Company’s discretion, the redemption date may be delayed until such time as any or all such conditions shall be satisfied (or waived by the Company in its sole discretion), such redemption may not occur and such notice may be rescinded in the event that any or all of such conditions shall not have been satisfied (or waived by the Company in its sole discretion) by the redemption date, or by the redemption date so delayed. (9) DENOMINATIONS, TRANSFER, EXCHANGE. The Notes are in registered form without coupons in minimum denominations of $2,000 and integral multiples of $1,000 in excess thereof. The transfer of Notes may be registered and Notes may be exchanged as provided in the Indenture. The Registrar and the Trustee may require a Holder, among other things, to furnish appropriate endorsements and transfer documents and the Company may require a Holder to pay any taxes and fees required by law or permitted by the Indenture. The Company need not exchange or register the transfer of any Note or portion of a Note selected for redemption, except for the unredeemed portion of any Note being redeemed in part. Also, the Company need not exchange or register the transfer of any Notes for a period of 15 days before a selection of Notes to be redeemed or during the period between a record date and the corresponding Interest Payment Date. (10) PERSONS DEEMED OWNERS. The registered Holder of a Note may be treated as its owner for all purposes. (11) AMENDMENT, SUPPLEMENT AND WAIVER. Subject to certain exceptions, the Indenture or the Notes may be amended or supplemented with the consent of the Holders of a majority in aggregate principal amount of the then outstanding Notes including Additional Notes, if any, voting as a single class, and any existing Default or Event or Default or compliance with any provision of the Indenture or the Notes may be waived with the consent of the Holders of a majority in aggregate principal amount of the then outstanding Notes including Additional Notes, if any, voting as a single class. Without the consent of any Holder, the Indenture or the Notes, may be amended or supplemented to cure any ambiguity, defect or inconsistency in the Indenture or the Notes in a manner that does not adversely affect the rights of any Holder, to provide for uncertificated Notes in addition to or in place of certificated Notes, to provide for the assumption of the Company’s obligations to Holders in case of a merger or consolidation or sale of all or substantially all of the Company’s assets, to make any change that would provide any additional rights or benefits to the Holders or that does not adversely affect the legal rights under the Indenture of any such Holder, to conform the text of the Indenture or the Notes to any provision of the “Description of Notes” section of the Offering Memorandum, to the extent that such provision in that “Description of Notes” was intended to be a verbatim or substantially verbatim recitation of a provision of the Indenture or this Note, to evidence and provide for the acceptance and appointment under the Indenture of successor trustees pursuant to the requirements thereof or to provide for the issuance of Additional Notes of the same or an additional series in accordance with the limitations set forth in the Indenture as of the date hereof. (12) DEFAULTS AND REMEDIES. Events of Default include: (i) default for 30 days in the payment when due of interest on the Notes; (ii) default in payment when due of the principal of, or premium, if any, on, the Notes; and (iii) (a) a court of competent jurisdiction (x) enters an order or decree under any Bankruptcy Law that is for relief against the Company or any of its Material Subsidiaries in an involuntary case; (y) appoints a custodian for all or substantially all of the property of the Company or any of its Material Subsidiaries; or (z) orders the liquidation of the Company or any of its Material Subsidiaries and, in each

A-6 of clauses (x), (y) or (z), the order, appointment or decree remains unstayed and in effect for at least 60 consecutive days; or (b) the Company or any of its Material Subsidiaries, pursuant to or within the meaning of Bankruptcy Law, (w) commences a voluntary case; (x) consents to the entry of an order for relief against it in an involuntary case; (y) consents to the appointment of a custodian of it or for all or substantially all of its property; or (z) makes a general assignment for the benefit of its creditors. In the case of an Event of Default of the type specified in clause (iii) above, all outstanding Notes will become due and payable immediately without further action or notice. If any other Event of Default occurs and is continuing, the Trustee or the Holders of at least 25% in aggregate principal amount of the then outstanding Notes may declare all the Notes to be due and payable immediately. Holders may not enforce the Indenture or the Notes except as provided in the Indenture. Subject to certain limitations, Holders of a majority in aggregate principal amount of the then outstanding Notes may direct the Trustee in its exercise of any trust or power. The Trustee may withhold from Holders of the Notes notice of any continuing Default or Event of Default (except a Default or Event of Default relating to the payment of principal or interest or premium, if any,) if it determines that withholding notice is in their interest. The Holders of a majority in aggregate principal amount of the then outstanding Notes by notice to the Trustee may, on behalf of the Holders of all of the Notes, rescind an acceleration or waive any existing Default or Event of Default and its consequences under the Indenture except a continuing Default or Event of Default in the payment of interest or premium, if any, on, or the principal of, the Notes. The Company is required to deliver to the Trustee annually a statement regarding compliance with the Indenture, and the Company is required, upon becoming aware of any Default or Event of Default, to deliver to the Trustee a statement specifying such Default or Event of Default. (13) TRUSTEE DEALINGS WITH COMPANY. The Trustee, in its individual or any other capacity, may make loans to, accept deposits from, and perform services for the Company or its Affiliates, and may otherwise deal with the Company or its Affiliates, as if it were not the Trustee. (14) NO RECOURSE AGAINST OTHERS. A director, officer, employee, incorporator or stockholder of the Company, as such, will not have any liability for any obligations of the Company under the Notes or the Indenture or for any claim based on, in respect of, or by reason of, such obligations or their creation. Each Holder by accepting a Note waives and releases all such liability. The waiver and release are part of the consideration for the issuance of the Notes. (15) AUTHENTICATION. This Note will not be valid until authenticated by the manual signature of the Trustee or an authenticating agent. (16) ABBREVIATIONS. Customary abbreviations may be used in the name of a Holder or an assignee, such as: TEN COM (= tenants in common), TEN ENT (= tenants by the entireties), JT TEN (= joint tenants with right of survivorship and not as tenants in common), CUST (= Custodian), and U/G/M/A (= Uniform Gifts to Minors Act). (17) CUSIP NUMBERS. Pursuant to a recommendation promulgated by the Committee on Uniform Security Identification Procedures, the Company has caused CUSIP numbers to be printed on the Notes, and the Trustee may use CUSIP numbers in notices of redemption as a convenience to Holders. No representation is made as to the accuracy of such numbers either as printed on the Notes or as contained in any notice of redemption, and reliance may be placed only on the other identification numbers placed thereon. (18) GOVERNING LAW. THE INTERNAL LAW OF THE STATE OF NEW YORK WILL GOVERN AND BE USED TO CONSTRUE THE INDENTURE AND THIS NOTE WITHOUT GIVING EFFECT TO APPLICABLE PRINCIPLES OF CONFLICTS OF LAW TO THE EXTENT THAT THE APPLICATION OF THE LAWS OF ANOTHER JURISDICTION WOULD BE REQUIRED THEREBY.

A-7 The Company will furnish to any Holder upon written request and without charge a copy of the Indenture. Requests may be made to: Calpine LLC c/o Constellation Energy Generation, LLC 200 Energy Way Kennett Square, PA, 19348-2473 Attention: Legal Department Email: legalnotices@constellation.com

A-8 ASSIGNMENT FORM To assign this Note, fill in the form below: (I) or (we) assign and transfer this Note to: (Insert assignee’s legal name) (Insert assignee’s soc. sec. or tax I.D. no.) (Print or type assignee’s name, address and zip code) and irrevocably appoint to transfer this Note on the books of the Company. The agent may substitute another to act for him. Date: _______________ Your Signature: (Sign exactly as your name appears on the face of this Note) Signature Guarantee*: _________________________ * Participant in a recognized Signature Guarantee Medallion Program (or other signature guarantor acceptable to the Trustee).

A-9 SCHEDULE OF EXCHANGES OF INTERESTS IN THE GLOBAL NOTE * The following exchanges of a part of this Global Note for an interest in another Global Note or for a Definitive Note, or exchanges of a part of another Global Note or Definitive Note for an interest in this Global Note, have been made: Date of Exchange Amount of decrease in Principal Amount of this Global Note Amount of increase in Principal Amount of this Global Note Principal Amount of this Global Note following such decrease (or increase) Signature of authorized officer of Trustee or Custodian * This schedule should be included only if the Note is issued in global form.

ceg-202601158kexh42

#4936-1412-8007 v2 FIRST SUPPLEMENTAL INDENTURE between CALPINE LLC and WILMINGTON TRUST, NATIONAL ASSOCIATION, as Trustee Dated as of January 15, 2026 Supplementing and Amending the Indenture Dated as of August 10, 2020

This First Supplemental Indenture is dated as of January 15, 2026 (this “Supplement”), and is between Calpine LLC, a Delaware limited liability company (formerly Calpine Corporation, a Delaware corporation) (the “Company”), and Wilmington Trust, National Association, as trustee (the “Trustee”), and supplements and amends the Indenture, dated as of August 10, 2020 (as previously supplemented, the “Existing Indenture”), between the Company and the Trustee. WHEREAS, pursuant to the Existing Indenture, the Company issued its 5.000% Senior Notes due 2031 (the “Notes”); WHEREAS, pursuant to Section 9.02 (With Consent of Holders) of the Existing Indenture, the Company and the Trustee may amend or supplement the Existing Indenture and the Notes with the consent of the Holders of a majority in aggregate principal amount of the then outstanding Notes (including, without limitation, Additional Notes, if any) voting as a single class (including, without limitation, consents obtained in connection with a tender offer or exchange offer for, or purchase of, the Notes), and, subject to Sections 6.04 (Waiver of Past Defaults) and 6.07 (Rights of Holders to Receive Payment) of the Existing Indenture, any existing Default or Event of Default (other than a Default or Event of Default in the payment of the principal of, premium, if any, or interest on, the Notes, except a payment default resulting from an acceleration that has been rescinded) or compliance with any provision of the Existing Indenture or the Notes may be waived with the consent of the Holders of a majority in aggregate principal amount of the then outstanding Notes (including, without limitation, Additional Notes, if any) voting as a single class (including, without limitation, consents obtained in connection with a tender offer or exchange offer for, or purchase of, the Notes); and WHEREAS, all acts and things necessary to constitute this Supplement a valid indenture and agreement according to its terms have been done and performed, including the requisite consent of the Holders of a majority in aggregate principal amount of the then outstanding Notes, and the Company and the Trustee have duly authorized the execution and delivery of this Supplement and the amended and restated Notes. NOW, THEREFORE, the parties hereby agree as follows: Section 1. Definitions. Each capitalized term used but not otherwise defined herein has the meaning given to it in the Existing Indenture. Section 2. Amendments to Existing Indenture. From and after the date hereof: The Existing Indenture is hereby amended by deleting all references to “Calpine Corporation” therein and replacing them with “Calpine LLC”. The Existing Indenture is hereby amended by deleting all references to “a Delaware corporation” therein and replacing them with “a Delaware limited liability company”. Section 1.02 (Other Definitions) of the Existing Indenture is hereby amended by deleting the definitions of “Change of Control Offer”, “Change of Control Payment” and “Change of Control Payment Date”. Sections 4.03 (Reports), 4.04 (Compliance Certificate), 4.05 (Taxes), 4.06 (Stay, Extension and Usury Laws), 4.07 (Liens), 4.08 (Corporate Existence), 4.09 (Offer to Repurchase Upon Change of Control Triggering Event), and 5.01 (Merger, Consolidation, or Sale of Assets) of the Existing Indenture are each hereby deleted in their entirety and replaced as follows:

-4- together represent the same agreement. Delivery of an executed counterpart of a signature page to this Supplement and other Executed Documentation by telecopier, facsimile or other electronic transmission (e.g. a “pdf” or “tif”) shall be effective as delivery of a manually executed counterpart thereof. The exchange of copies of this Supplement and other Executed Documentation and of signature pages by telecopier, facsimile or other electronic transmission (e.g. a “pdf” or “tif”) shall constitute effective execution and delivery of this Supplement and other Executed Documentation as to the parties hereto and may be used in lieu of the original Supplement or other Executed Documentation and signature pages for all purposes. “Electronic Signatures” means any electronic signatures covered by the Electronic Signatures in Global and National Commerce Act of 2000, Uniform Electronic Transactions Act, the Electronic Signatures and Records Act or other applicable law (e.g., www.docusign.com). [Remainder of Page Intentionally Left Blank]

WILMINGTON TRUST, NATIONAL ASSOCIATION, as Trustee By: Name: Title:

A-1 EXHIBIT A FORM OF AMENDED AND RESTATED NOTES [Face of Note] [Insert the Global Note Legend, if applicable pursuant to the provisions of the Indenture] [Insert the Private Placement Legend, if applicable pursuant to the provisions of the Indenture] CUSIP/ISIN ____________ [RULE 144A][REGULATION S][GLOBAL] NOTE 5.000% Senior Notes due 2031 No. ___ $___________ CALPINE LLC promises to pay to or registered assigns, the principal sum of DOLLARS on February 1, 2031. Interest Payment Dates: February 1 and August 1 Record Dates: January 15 and July 15 [Signature Page Follows]

A-3 [Back of Note] 5.000% Senior Notes due 2031 Capitalized terms used herein have the meanings assigned to them in the Indenture referred to below unless otherwise indicated. (1) INTEREST. Calpine LLC, a Delaware limited liability company (formerly Calpine Corporation, a Delaware corporation) (the “Company”), promises to pay interest on the principal amount of this Note at 5.000% per annum from August 10, 2020 1 until maturity. The Company will pay interest semi-annually in arrears on February 1 and August 1 of each year (each, an “Interest Payment Date”), or if any such day is not a Business Day, on the next succeeding Business Day. Interest on the Notes will accrue from the most recent Interest Payment Date to which interest has been paid or, if no interest has been paid, from the date of issuance; provided that if there is no existing Default in the payment of interest, and if this Note is authenticated between a record date referred to on the face hereof and the next succeeding Interest Payment Date, interest shall accrue from such next succeeding Interest Payment Date; provided further that the first Interest Payment Date shall be February 1, 2021 2 . Interest will be computed on the basis of a 360- day year of twelve 30-day months. (2) METHOD OF PAYMENT. The Company will pay interest on the Notes (except defaulted interest) to the Persons who are registered Holders at the close of business on January 15 or July 15 next preceding the Interest Payment Date, even if such Notes are canceled after such record date and on or before such Interest Payment Date, except as provided in Section 2.12 of the Indenture with respect to defaulted interest. The Notes will be payable as to principal, premium, if any, and interest at the office or agency of the Company maintained for such purpose or, at the option of the Company, payment of interest may be made by check mailed to the Holders at their addresses set forth in the register of Holders; provided that payment by wire transfer of immediately available funds will be required with respect to principal of and interest, premium on, all Global Notes and all other Notes the Holders of which will have provided wire transfer instructions to the Company or the Paying Agent. Such payment will be in such coin or currency of the United States of America as at the time of payment is legal tender for payment of public and private debts. (3) PAYING AGENT AND REGISTRAR. Initially, Wilmington Trust, National Association, the Trustee under the Indenture, will act as Paying Agent and Registrar. The Company may change any Paying Agent or Registrar without notice to any Holder. The Company or any of its Subsidiaries may act in any such capacity. (4) INDENTURE. The Company issued the Notes under an Indenture dated as of August 10, 2020 (as amended or supplemented from time to time, including as of January [ ], 2026, the “Indenture”) among the Company and the Trustee. The Notes are subject to all such terms, and Holders are referred to the Indenture for a statement of such terms. To the extent any provision of this Note conflicts with the express provisions of the Indenture, the provisions of the Indenture shall govern and be controlling. The Notes are unsecured obligations of the Company. The indenture does not limit the aggregate principal amount of Notes that may be issued thereunder. (5) OPTIONAL REDEMPTION. (a) On or after February 1, 2026, the Company may on any one or more occasions redeem all or a part of the Notes, upon not less than 30 nor more than 60 days’ notice, at the redemption prices 1 With respect to the Initial Notes. 2 With respect to the Initial Notes.

A-4 (expressed as percentages of principal amount) set forth below, plus accrued and unpaid interest, if any, on the Notes redeemed, to but excluding the applicable date of redemption, if redeemed during the twelve- month period beginning on February 1 of the years indicated below, subject to the rights of Holders on the relevant record date to receive interest on the relevant interest payment date: Year Percentage 2026 ............................................................................................................ 102.500% 2027 ............................................................................................................ 101.667% 2028 ............................................................................................................ 100.833% 2029 and thereafter ..................................................................................... 100.000% Unless the Company defaults in the payment of the redemption price, interest will cease to accrue on the Notes or portions thereof called for redemption on the applicable redemption date. (b) At any time prior to February 1, 2024, the Company may on any one or more occasions redeem up to 35% of the aggregate principal amount of Notes issued under the Indenture, upon not less than 30 nor more than 60 days’ notice, at a redemption price equal to 105.000% of the principal amount of the Notes redeemed, plus accrued and unpaid interest, if any, to but excluding the date of redemption (subject to the rights of Holders on the relevant record date to receive interest on the relevant interest payment date), with the proceeds of one or more Equity Offerings; provided that: (i) at least 65% of the aggregate principal amount of Notes originally issued under the Indenture (excluding Notes held by the Company and its Subsidiaries) remains outstanding immediately after the occurrence of such redemption; and (ii) the redemption occurs within 90 days of the date of the closing of such Equity Offering. (c) At any time prior to February 1, 2026, the Company may on any one or more occasions redeem all or a part of the Notes, upon not less than 30 nor more than 60 days’ notice, at a redemption price equal to 100% of the principal amount of the Notes redeemed, plus the Applicable Premium as of, and accrued and unpaid interest, if any, to but excluding the date of redemption, subject to the rights of Holders on the relevant record date to receive interest due on the relevant interest payment date. (d) At any time, in connection with any tender offer for the Notes, if Holders of not less than 90% in aggregate principal amount of the outstanding Notes validly tender and do not withdraw such Notes in such tender offer and the Company, or any third party making such tender offer in lieu of the Company, purchases all of the Notes validly tendered and not withdrawn by such Holders, the Company may, upon not less than 10 nor more than 60 days’ prior notice, given not more than 30 days following such purchase date, redeem all Notes that remain outstanding following such purchase at a redemption price equal to the price paid to each other Holder in such tender offer plus, to the extent not included in the tender offer payment, accrued and unpaid interest, if any, thereon, to, but not excluding, the date of such redemption (subject to the rights of Holders on the relevant record date to receive interest on the relevant interest payment date). (6) MANDATORY REDEMPTION. The Company is not required to make mandatory redemption or sinking fund payments with respect to the Notes. (7) RESERVED. (8) NOTICE OF REDEMPTION. Notice of redemption will be mailed or delivered electronically at least 30 days but not more than 60 days before the redemption date to each Holder whose Notes are to be redeemed at its registered address, except that (i) redemption notices may be mailed or

A-5 delivered electronically at least 10 days prior to the redemption date if the notice is issued in connection with a redemption pursuant to Section 3.07(c) of the Indenture and (ii) redemption notices may be mailed or delivered electronically more than 60 days prior to a redemption date if the notice is issued in connection with a defeasance of the Notes or a satisfaction or discharge of the Indenture. Notes in denominations larger than $2,000 may be redeemed in part but only in whole multiples of $1,000, unless all of the Notes held by a Holder are to be redeemed. Any redemption notice may, in the Company’s discretion, be subject to the satisfaction of one or more conditions precedent. If such redemption is subject to the satisfaction of one of more conditions precedent, such notice shall state that, in the Company’s discretion, the redemption date may be delayed until such time as any or all such conditions shall be satisfied (or waived by the Company in its sole discretion), such redemption may not occur and such notice may be rescinded in the event that any or all of such conditions shall not have been satisfied (or waived by the Company in its sole discretion) by the redemption date, or by the redemption date so delayed. (9) DENOMINATIONS, TRANSFER, EXCHANGE. The Notes are in registered form without coupons in minimum denominations of $2,000 and integral multiples of $1,000 in excess thereof. The transfer of Notes may be registered and Notes may be exchanged as provided in the Indenture. The Registrar and the Trustee may require a Holder, among other things, to furnish appropriate endorsements and transfer documents and the Company may require a Holder to pay any taxes and fees required by law or permitted by the Indenture. The Company need not exchange or register the transfer of any Note or portion of a Note selected for redemption, except for the unredeemed portion of any Note being redeemed in part. Also, the Company need not exchange or register the transfer of any Notes for a period of 15 days before a selection of Notes to be redeemed or during the period between a record date and the corresponding Interest Payment Date. (10) PERSONS DEEMED OWNERS. The registered Holder of a Note may be treated as its owner for all purposes. (11) AMENDMENT, SUPPLEMENT AND WAIVER. Subject to certain exceptions, the Indenture or the Notes may be amended or supplemented with the consent of the Holders of a majority in aggregate principal amount of the then outstanding Notes including Additional Notes, if any, voting as a single class, and any existing Default or Event or Default or compliance with any provision of the Indenture or the Notes may be waived with the consent of the Holders of a majority in aggregate principal amount of the then outstanding Notes including Additional Notes, if any, voting as a single class. Without the consent of any Holder, the Indenture or the Notes, may be amended or supplemented to cure any ambiguity, defect or inconsistency in the Indenture or the Notes in a manner that does not adversely affect the rights of any Holder, to provide for uncertificated Notes in addition to or in place of certificated Notes, to provide for the assumption of the Company’s obligations to Holders in case of a merger or consolidation or sale of all or substantially all of the Company’s assets, to make any change that would provide any additional rights or benefits to the Holders or that does not adversely affect the legal rights under the Indenture of any such Holder, to conform the text of the Indenture or the Notes to any provision of the “Description of Notes” section of the Offering Memorandum, to the extent that such provision in that “Description of Notes” was intended to be a verbatim or substantially verbatim recitation of a provision of the Indenture or this Note, to evidence and provide for the acceptance and appointment under the Indenture of successor trustees pursuant to the requirements thereof or to provide for the issuance of Additional Notes of the same or an additional series in accordance with the limitations set forth in the Indenture as of the date hereof. (12) DEFAULTS AND REMEDIES. Events of Default include: (i) default for 30 days in the payment when due of interest on the Notes; (ii) default in payment when due of the principal of, or premium, if any, on, the Notes; and (iii) (a) a court of competent jurisdiction (x) enters an order or decree under any Bankruptcy Law that is for relief against the Company or any of its Material Subsidiaries in an involuntary case; (y) appoints a custodian for all or substantially all of the property of the Company or any of its Material

A-6 Subsidiaries; or (z) orders the liquidation of the Company or any of its Material Subsidiaries and, in each of clauses (x), (y) or (z), the order, appointment or decree remains unstayed and in effect for at least 60 consecutive days; or (b) the Company or any of its Material Subsidiaries, pursuant to or within the meaning of Bankruptcy Law, (w) commences a voluntary case; (x) consents to the entry of an order for relief against it in an involuntary case; (y) consents to the appointment of a custodian of it or for all or substantially all of its property; or (z) makes a general assignment for the benefit of its creditors. In the case of an Event of Default of the type specified in clause (iii) above, all outstanding Notes will become due and payable immediately without further action or notice. If any other Event of Default occurs and is continuing, the Trustee or the Holders of at least 25% in aggregate principal amount of the then outstanding Notes may declare all the Notes to be due and payable immediately. Holders may not enforce the Indenture or the Notes except as provided in the Indenture. Subject to certain limitations, Holders of a majority in aggregate principal amount of the then outstanding Notes may direct the Trustee in its exercise of any trust or power. The Trustee may withhold from Holders of the Notes notice of any continuing Default or Event of Default (except a Default or Event of Default relating to the payment of principal or interest or premium, if any,) if it determines that withholding notice is in their interest. The Holders of a majority in aggregate principal amount of the then outstanding Notes by notice to the Trustee may, on behalf of the Holders of all of the Notes, rescind an acceleration or waive any existing Default or Event of Default and its consequences under the Indenture except a continuing Default or Event of Default in the payment of interest or premium, if any, on, or the principal of, the Notes. The Company is required to deliver to the Trustee annually a statement regarding compliance with the Indenture, and the Company is required, upon becoming aware of any Default or Event of Default, to deliver to the Trustee a statement specifying such Default or Event of Default. (13) TRUSTEE DEALINGS WITH COMPANY. The Trustee, in its individual or any other capacity, may make loans to, accept deposits from, and perform services for the Company or its Affiliates, and may otherwise deal with the Company or its Affiliates, as if it were not the Trustee. (14) NO RECOURSE AGAINST OTHERS. A director, officer, employee, incorporator or stockholder of the Company, as such, will not have any liability for any obligations of the Company under the Notes or the Indenture or for any claim based on, in respect of, or by reason of, such obligations or their creation. Each Holder by accepting a Note waives and releases all such liability. The waiver and release are part of the consideration for the issuance of the Notes. (15) AUTHENTICATION. This Note will not be valid until authenticated by the manual signature of the Trustee or an authenticating agent. (16) ABBREVIATIONS. Customary abbreviations may be used in the name of a Holder or an assignee, such as: TEN COM (= tenants in common), TEN ENT (= tenants by the entireties), JT TEN (= joint tenants with right of survivorship and not as tenants in common), CUST (= Custodian), and U/G/M/A (= Uniform Gifts to Minors Act). (17) CUSIP NUMBERS. Pursuant to a recommendation promulgated by the Committee on Uniform Security Identification Procedures, the Company has caused CUSIP numbers to be printed on the Notes, and the Trustee may use CUSIP numbers in notices of redemption as a convenience to Holders. No representation is made as to the accuracy of such numbers either as printed on the Notes or as contained in any notice of redemption, and reliance may be placed only on the other identification numbers placed thereon. (18) GOVERNING LAW. THE INTERNAL LAW OF THE STATE OF NEW YORK WILL GOVERN AND BE USED TO CONSTRUE THE INDENTURE AND THIS NOTE WITHOUT GIVING

A-7 EFFECT TO APPLICABLE PRINCIPLES OF CONFLICTS OF LAW TO THE EXTENT THAT THE APPLICATION OF THE LAWS OF ANOTHER JURISDICTION WOULD BE REQUIRED THEREBY. The Company will furnish to any Holder upon written request and without charge a copy of the Indenture. Requests may be made to: Calpine LLC c/o Constellation Energy Generation, LLC 200 Energy Way Kennett Square, PA, 19348-2473 Attention: Legal Department Email: legalnotices@constellation.com

ceg-202601158kexh43

#4917-3501-4279 v2 SECOND SUPPLEMENTAL INDENTURE between CALPINE LLC and WILMINGTON TRUST, NATIONAL ASSOCIATION, as Trustee Dated as of January 15, 2026 Supplementing and Amending the Indenture Dated as of December 16, 2020

This Second Supplemental Indenture is dated as of January 15, 2026 (this “Supplement”), and is by and among Calpine LLC, a Delaware limited liability company (formerly Calpine Corporation, a Delaware corporation) (the “Company”), the guarantors party to the Existing Indenture (as defined below), Wilmington Trust, National Association, as trustee (the “Trustee”), and supplements and amends the Indenture, dated as of December 16, 2020 (as previously supplemented and amended, including by the First Supplemental Indenture, dated as of August 20, 2025, the “Existing Indenture”), between the Company and the Trustee. WHEREAS, pursuant to the Existing Indenture, the Company issued its 3.750% Senior Secured Notes due 2031 (the “Notes”); WHEREAS, pursuant to Section 9.02 (With Consent of Holders) of the Existing Indenture (and subject to Section 10.05 (Amendment of Security Documents)), the Company and the Trustee may amend or supplement the Existing Indenture and the Notes with the consent of the Holders of a majority in aggregate principal amount of the then outstanding Notes (including, without limitation, Additional Notes, if any) voting as a single class (including, without limitation, consents obtained in connection with a tender offer or exchange offer for, or purchase of, the Notes), and, subject to Sections 6.04 (Waiver of Past Defaults) and 6.07 (Rights of Holders to Receive Payment) of the Existing Indenture, any existing Default or Event of Default (other than a Default or Event of Default in the payment of the principal of, premium, if any, or interest on, the Notes, except a payment default resulting from an acceleration that has been rescinded) or compliance with any provision of the Existing Indenture or the Notes may be waived with the consent of the Holders of a majority in aggregate principal amount of the then outstanding Notes (including, without limitation, Additional Notes, if any) voting as a single class (including, without limitation, consents obtained in connection with a tender offer or exchange offer for, or purchase of, the Notes); and WHEREAS, all acts and things necessary to constitute this Supplement a valid indenture and agreement according to its terms have been done and performed, including the requisite consent of the Holders of a majority in aggregate principal amount of the then outstanding Notes (or as applicable, at least 66-2/3% in aggregate principal amount of Notes then outstanding), and the Company and the Trustee have duly authorized the execution and delivery of this Supplement and the amended and restated Notes. NOW, THEREFORE, the parties hereby agree as follows: Section 1. Definitions. Each capitalized term used but not otherwise defined herein has the meaning given to it in the Existing Indenture. Section 2. Amendments to Existing Indenture. From and after the date hereof: The Existing Indenture is hereby amended by deleting all references to “Calpine Corporation” therein and replacing them with “Calpine LLC”. The Existing Indenture is hereby amended by deleting all references to “a Delaware corporation” therein and replacing them with “a Delaware limited liability company”. The Existing Indenture is hereby amended by deleting all references to “3.750% Senior Secured Notes due 2031” therein (including any exhibits thereto) and replacing them with “3.750% Senior Notes due 2031” The definition of “First Lien Documents” included in Section 1.01 (Definitions) of the Existing Indenture is hereby amended by deleting “this Indenture,” from such definition.

-2- Section 1.01 (Definitions) of the Existing Indenture is hereby amended by deleting the following definitions: “CNTA Ratio” and “Consolidated Net Tangible Assets”. Section 1.02 (Other Definitions) of the Existing Indenture is hereby amended by deleting the definitions of “Change of Control Offer”, “Change of Control Payment”, “Change of Control Payment Date”, and “Title Datedown Product”. Sections 4.03 (Reports), 4.04 (Compliance Certificate), 4.05 (Taxes), 4.06 (Stay, Extension and Usury Laws), 4.07 (Incurrence of Indebtedness), 4.08 (Limitation on Secured Commodity Hedging), 4.09 (Liens), 4.10 (Corporate Existence), 4.11 (Offer to Repurchase Upon Change of Control Triggering Event), 4.12 (Limitation on Sale and Leaseback Transactions), 4.13 (Additional Note Guarantees), 4.14 (Further Assurances; Insurance), 4.15 (After-Acquired Collateral), 5.01 (Merger, Consolidation, or Sale of Assets), and 10.01 (Security Interest) of the Existing Indenture are each hereby deleted in their entirety and replaced as follows: “Section 4.03 Reserved” “Section 4.04 Reserved” “Section 4.05 Reserved” “Section 4.06 Reserved” “Section 4.07 Reserved” “Section 4.08 Reserved” “Section 4.10 Reserved” “Section 4.11 Reserved” “Section 4.12 Reserved” “Section 4.13 Reserved” “Section 4.14 Reserved” “Section 4.15 Reserved” “Section 5.01 Reserved” “Section 10.01 Reserved” provided further that, the Table of Contents set forth in the Existing Indenture shall be updated accordingly. Section 5.02 (Successor Corporation Substituted) of the Existing Indenture is hereby amended by deleting “in a transaction that is subject to, and that complies with the provisions of, Section 5.01 hereof” and “; provided, however, that the predecessor Company shall not be relieved from the obligation to pay the principal of and interest on the Notes except in the case of a sale of all of the Company’s assets in a transaction that is subject to, and that complies with the provisions of, Section 5.01 hereof” from such section.

-3- Clauses (4), (5), (6), (7), and (8) of Section 6.01 (Events of Default) of the Existing Indenture are each hereby deleted in their entirety. The last sentence of Section 8.03 (Covenant Defeasance) of the Existing Indenture is hereby deleted in its entirety. Clause (2) of Section 9.02 (With Consent of Holders) of the Existing Indenture is hereby amended by deleting the following from such clause: “other than provisions relating to Section 4.11 hereof and”. Clause (7) of Section 9.02 (With Consent of Holders) of the Existing Indenture is hereby amended by deleting “(other than a payment required by Section 4.11 hereof)” from such clause. Section 3. Waiver. Subject to Section 6.04 (Waiver of Past Defaults) and Section 6.07 (Rights of Holders to Receive Payment) of the Existing Indenture, the Holders hereby waive (i) any existing Default or Event of Default and its consequences under the Existing Indenture and/or (ii) any current or future Default or Event of Default and its consequences under the Existing Indenture, in each case relating to the provisions of the Existing Indenture that have been deleted pursuant to this Supplement. Section 4. Authorization of Amended and Restated Notes. Upon the execution and delivery of this Supplement, the outstanding Notes shall each be, or be deemed to be, amended and restated substantially in the form attached to this Supplement as Exhibit A. Section 5. Notices. Pursuant to Section 13.01 (Notices) of the Existing Indenture, the Company hereby designates the following addresses for subsequent notices and communications: Calpine LLC c/o Constellation Energy Generation, LLC 200 Energy Way Kennett Square, PA, 19348-2473 Attention: Legal Department Email: legalnotices@constellation.com Telephone: (833) 883-0162 with a copy to (which shall not constitute notice): Ballard Spahr LLP Attention: Patrick R. Gillard, Esq. Telephone: (215) 864-8536 Email: gillard@ballardspahr.com Section 6. Execution and Authentication. Upon delivery of an executed copy of this Supplement, executed copies of an Officer’s Certificate and an Opinion of Counsel required by Section 9.05 (Trustee to Sign Amendments, etc.) of the Existing Indenture and an authentication and cancellation order, the Company may deliver amended and restated Notes to the Trustee for authentication as provided for in the Existing Indenture. Section 7. Ratification of Existing Indenture. As supplemented and amended hereby, the Existing Indenture is hereby, in all respects, ratified and confirmed and the Existing Indenture, as supplemented and amended hereby, shall be read, taken and construed as one and the same instrument.

-4- Section 8. Severability. If any provision of this Supplement shall be held invalid by any court of competent jurisdiction, such holding shall not invalidate any other provision hereof. Section 9. Counterparts. This Supplement may be executed in several counterparts, each of which together shall be an original and all of which shall constitute one instrument. Section 10. Governing Law. THE INTERNAL LAW OF THE STATE OF NEW YORK WILL GOVERN AND BE USED TO CONSTRUE THIS SUPPLEMENT AND THE NOTES WITHOUT GIVING EFFECT TO APPLICABLE PRINCIPLES OF CONFLICTS OF LAW TO THE EXTENT THAT THE APPLICATION OF THE LAWS OF ANOTHER JURISDICTION WOULD BE REQUIRED THEREBY. Section 11. The Trustee. The Trustee makes no representation or warranty as to the validity or sufficiency of this Supplement or with respect to the recitals contained herein, all of which recitals are made solely by the other parties hereto. To the extent that the requisite consents to any amendment effected by this Supplement are determined by a court of competent jurisdiction to have not been validly obtained in accordance with the Existing Indenture or applicable laws, such amendment shall not be deemed to have occurred. Section 12. Electronic Signatures. The parties may sign any number of copies of this Supplement. Signatures to this Supplement or any instrument, agreement or document necessary for the consummation of the transactions contemplated by this Supplement or related hereto or thereto (including, without limitation, addendums, amendments, notices, instructions, communications with respect to the delivery of securities or the wire transfer of funds or other communications) (“Executed Documentation”) may be manual, facsimile, or Electronic Signatures. Each signed copy shall be an original, but all of them together represent the same agreement. Delivery of an executed counterpart of a signature page to this Supplement and other Executed Documentation by telecopier, facsimile or other electronic transmission (e.g. a “pdf” or “tif”) shall be effective as delivery of a manually executed counterpart thereof. The exchange of copies of this Supplement and other Executed Documentation and of signature pages by telecopier, facsimile or other electronic transmission (e.g. a “pdf” or “tif”) shall constitute effective execution and delivery of this Supplement and other Executed Documentation as to the parties hereto and may be used in lieu of the original Supplement or other Executed Documentation and signature pages for all purposes. “Electronic Signatures” means any electronic signatures covered by the Electronic Signatures in Global and National Commerce Act of 2000, Uniform Electronic Transactions Act, the Electronic Signatures and Records Act or other applicable law (e.g., www.docusign.com). [Remainder of Page Intentionally Left Blank]

IN WITNESS WHEREOF, the Company, the Guarantors and the Trustee have caused this Supplement to be executed and delivered by duly authorized officers thereof as of the day and year first written above. CALPINE LLC, a Delaware limited liability company By: Name: Eugene P. Miles Title: Assistant Treasurer THE GUARANTORS PARTY TO THE EXISTING INDENTURE, By: Name: Eugene P. Miles Title: Assistant Treasurer

WILMINGTON TRUST, NATIONAL ASSOCIATION, as Trustee By: Name: Title:

A-1 EXHIBIT A FORM OF AMENDED AND RESTATED NOTES [Face of Note] [Insert the Global Note Legend, if applicable pursuant to the provisions of the Indenture] [Insert the Private Placement Legend, if applicable pursuant to the provisions of the Indenture] [Insert the Regulation S Temporary Global Note Legend, if applicable pursuant to the provisions of the Indenture] CUSIP/ISIN ____________ [RULE 144A][REGULATION S][GLOBAL] NOTE 3.750% Senior Notes due 2031 No. ___ $___________ CALPINE LLC promises to pay to or registered assigns, the principal sum of DOLLARS on March 1, 2031. Interest Payment Dates: March 1 and September 1 Record Dates: February 15 and August 15 [Signature Page Follows]

A-2 IN WITNESS HEREOF, the Company has caused this Note to be signed manually or by facsimile by its duly authorized officer as of the date first written above. CALPINE LLC By: Name: Title: This is one of the Notes referred to in the within-mentioned Indenture: Dated: WILMINGTON TRUST, NATIONAL ASSOCIATION, as Trustee By: Authorized Signatory

A-3 [Back of Note] 3.750% Senior Notes due 2031 Capitalized terms used herein have the meanings assigned to them in the Indenture referred to below unless otherwise indicated. (1) INTEREST. Calpine LLC, a Delaware limited liability company (formerly Calpine Corporation, a Delaware corporation) (the “Company”), promises to pay interest on the principal amount of this Note at 3.750% per annum from December 16, 20201 until maturity. The Company will pay interest semi- annually in arrears on March 1 and September 1 of each year (each, an “Interest Payment Date”), or if any such day is not a Business Day, on the next succeeding Business Day. Interest on the Notes will accrue from the most recent Interest Payment Date to which interest has been paid or, if no interest has been paid, from the date of issuance; provided that if there is no existing Default in the payment of interest, and if this Note is authenticated between a record date referred to on the face hereof and the next succeeding Interest Payment Date, interest shall accrue from such next succeeding Interest Payment Date; provided further that the first Interest Payment Date shall be September 1, 20212. Interest will be computed on the basis of a 360-day year of twelve 30-day months. (2) METHOD OF PAYMENT. The Company will pay interest on the Notes (except defaulted interest) to the Persons who are registered Holders at the close of business on February 15 or August 15 next preceding the Interest Payment Date, even if such Notes are canceled after such record date and on or before such Interest Payment Date, except as provided in Section 2.12 of the Indenture with respect to defaulted interest. The Notes will be payable as to principal, premium, if any, and interest at the office or agency of the Company maintained for such purpose or, at the option of the Company, payment of interest may be made by check mailed to the Holders at their addresses set forth in the register of Holders; provided that payment by wire transfer of immediately available funds will be required with respect to principal of and interest, premium on, all Global Notes and all other Notes the Holders of which will have provided wire transfer instructions to the Company or the Paying Agent. Such payment will be in such coin or currency of the United States of America as at the time of payment is legal tender for payment of public and private debts. (3) PAYING AGENT AND REGISTRAR. Initially, Wilmington Trust, National Association, the Trustee under the Indenture, will act as Paying Agent and Registrar. The Company may change any Paying Agent or Registrar without notice to any Holder. The Company or any of its Subsidiaries may act in any such capacity. (4) INDENTURE. The Company issued the Notes under an Indenture dated as of December 16, 2020 (as amended or supplemented from time to time, the “Indenture”) among the Company, the Guarantors and the Trustee. The Notes are subject to all such terms, and Holders are referred to the Indenture for a statement of such terms. To the extent any provision of this Note conflicts with the express provisions of the Indenture, the provisions of the Indenture shall govern and be controlling. The Indenture does not limit the aggregate principal amount of Notes that may be issued thereunder. (5) OPTIONAL REDEMPTION. (a) On or after March 1, 2026, the Company may on any one or more occasions redeem all or a part of the Notes, upon not less than 30 nor more than 60 days’ notice, at the redemption prices (expressed as percentages of principal amount) set forth below, plus accrued and unpaid interest, if any, on the Notes redeemed, to but excluding the applicable date of redemption, if redeemed during the twelve-month 1 With respect to the Initial Notes 2 With respect to the Initial Notes

A-4 period beginning on March 1 of the years indicated below, subject to the rights of Holders on the relevant record date to receive interest on the relevant interest payment date: Year Percentage 2026 ............................................................................................................ 101.875% 2027 ............................................................................................................ 101.250% 2028 ............................................................................................................ 100.625% 2029 and thereafter ..................................................................................... 100.000% Unless the Company defaults in the payment of the redemption price, interest will cease to accrue on the Notes or portions thereof called for redemption on the applicable redemption date. (b) At any time prior to March 1, 2024, the Company may on any one or more occasions redeem up to 40% of the aggregate principal amount of Notes issued under the Indenture, upon not less than 30 nor more than 60 days’ notice, at a redemption price equal to 103.750% of the principal amount of the Notes redeemed, plus accrued and unpaid interest, if any, to but excluding the date of redemption (subject to the rights of Holders on the relevant record date to receive interest on the relevant interest payment date), with the proceeds of one or more Equity Offerings; provided that: (i) at least 50% of the aggregate principal amount of Notes originally issued under the Indenture (excluding Notes held by the Company and its Subsidiaries) remains outstanding immediately after the occurrence of such redemption; and (ii) the redemption occurs within 90 days of the date of the closing of such Equity Offering. (c) At any time prior to March 1, 2026, the Company may on any one or more occasions redeem all or a part of the Notes, upon not less than 30 nor more than 60 days’ notice, at a redemption price equal to 100% of the principal amount of the Notes redeemed, plus the Applicable Premium as of, and accrued and unpaid interest, if any, to but excluding the date of redemption, subject to the rights of Holders on the relevant record date to receive interest due on the relevant interest payment date. (d) The Company may redeem up to 10% of the aggregate principal amount of Notes issued under the Indenture during each 12-month period following March 1, 2021, that occurs prior to March 1, 2026, at a redemption price of 103% of the principal amount of Notes redeemed, plus accrued and unpaid interest, if any, to but excluding the redemption date (subject to the rights of Holders on the relevant record date to receive interest due on the relevant interest payment date). (e) At any time, in connection with any tender offer for the Notes, if Holders of not less than 90% in aggregate principal amount of the outstanding Notes validly tender and do not withdraw such Notes in such tender offer and the Company, or any third party making such tender offer in lieu of the Company, purchases all of the Notes validly tendered and not withdrawn by such Holders, the Company may, upon not less than 10 nor more than 60 days’ prior notice, given not more than 30 days following such purchase date, redeem all Notes that remain outstanding following such purchase at a redemption price equal to the price paid to each other Holder in such tender offer plus, to the extent not included in the tender offer payment, accrued and unpaid interest, if any, thereon, to, but not excluding, the date of such redemption (subject to the rights of Holders on the relevant record date to receive interest on the relevant interest payment date). (6) MANDATORY REDEMPTION. The Company is not required to make mandatory redemption or sinking fund payments with respect to the Notes. (7) RESERVED. (8) NOTICE OF REDEMPTION. Notice of redemption will be mailed or delivered electronically at least 30 days but not more than 60 days before the redemption date to each Holder whose Notes are to be redeemed at its registered address, except that (i) redemption notices may be mailed or delivered electronically at least 10 days prior to the redemption date if the notice is issued in connection

A-5 with a redemption pursuant to Section 3.07(c) of the Indenture and (ii) redemption notices may be mailed or delivered electronically more than 60 days prior to a redemption date if the notice is issued in connection with a defeasance of the Notes or a satisfaction or discharge of the Indenture. Notes in denominations larger than $2,000 may be redeemed in part but only in whole multiples of $1,000, unless all of the Notes held by a Holder are to be redeemed. Any redemption notice may, in the Company’s discretion, be subject to the satisfaction of one or more conditions precedent. If such redemption is subject to the satisfaction of one of more conditions precedent, such notice shall state that, in the Company’s discretion, the redemption date may be delayed until such time as any or all such conditions shall be satisfied (or waived by the Company in its sole discretion), such redemption may not occur and such notice may be rescinded in the event that any or all of such conditions shall not have been satisfied (or waived by the Company in its sole discretion) by the redemption date, or by the redemption date so delayed. (9) DENOMINATIONS, TRANSFER, EXCHANGE. The Notes are in registered form without coupons in minimum denominations of $2,000 and integral multiples of $1,000 in excess thereof. The transfer of Notes may be registered and Notes may be exchanged as provided in the Indenture. The Registrar and the Trustee may require a Holder, among other things, to furnish appropriate endorsements and transfer documents and the Company may require a Holder to pay any taxes and fees required by law or permitted by the Indenture. The Company need not exchange or register the transfer of any Note or portion of a Note selected for redemption, except for the unredeemed portion of any Note being redeemed in part. Also, the Company need not exchange or register the transfer of any Notes for a period of 15 days before a selection of Notes to be redeemed or during the period between a record date and the corresponding Interest Payment Date. (10) PERSONS DEEMED OWNERS. The registered Holder of a Note may be treated as its owner for all purposes. (11) AMENDMENT, SUPPLEMENT AND WAIVER. Subject to certain exceptions, the Indenture or the Notes or the Note Guarantees may be amended or supplemented with the consent of the Holders of a majority in aggregate principal amount of the Notes that are then outstanding including Additional Notes, if any, voting as a single class, and any existing Default or Event or Default or compliance with any provision of the Indenture or the Notes or the Note Guarantees may be waived with the consent of the Holders of a majority in aggregate principal amount of the Notes that are then outstanding including Additional Notes, if any, voting as a single class. Without the consent of any Holder, the Indenture, the Notes, or the Note Guarantees may be amended or supplemented to cure any ambiguity, defect or inconsistency in the Indenture, or the Notes in a manner that does not adversely affect the rights of any Holder, to provide for uncertificated Notes in addition to or in place of certificated Notes, to provide for the assumption of the Company’s or a Guarantor’s obligations to Holders in case of a merger or consolidation or sale of all or substantially all of the Company’s or such Guarantor’s assets, as applicable, to make any change that would provide any additional rights or benefits to the Holders or that does not adversely affect the legal rights under the Indenture of any such Holder, to conform the text of the Indenture or the Notes to any provision of the “Description of Notes” section of the Offering Memorandum, to the extent that such provision in that “Description of Notes” was intended to be a verbatim or substantially verbatim recitation of a provision of the Indenture, to evidence and provide for the acceptance and appointment under the Indenture of successor trustees pursuant to the requirements thereof, to allow any Guarantor to execute a supplemental indenture substantially in the form of Exhibit E to the Indenture and/or a joinder to the Guarantee or to provide for the issuance of Additional Notes of the same or an additional series in accordance with the limitations set forth in the Indenture as of the date hereof. (12) DEFAULTS AND REMEDIES. Events of Default include: (i) default for 30 days in the payment when due of interest on the Notes; (ii) default in payment when due (at maturity, upon redemption or otherwise) of the principal of, or premium, if any, on the Notes; and (iii) certain events of bankruptcy or insolvency described in the Indenture with respect to the Company or any Guarantor that is a Significant

A-6 Subsidiary or any group of Guarantors that, taken together, would constitute a Significant Subsidiary. If any Event of Default occurs and is continuing, the Trustee or the Holders of at least 25% in aggregate principal amount of the outstanding Notes may declare all the Notes to be due and payable immediately. Notwithstanding the foregoing, in the case of an Event of Default arising from certain events of bankruptcy or insolvency, all outstanding Notes will become due and payable immediately without further action or notice. Holders may not enforce the Indenture or the Notes except as provided in the Indenture. Subject to certain limitations, Holders of a majority in aggregate principal amount of the outstanding Notes may direct the Trustee in its exercise of any trust or power. The Trustee may withhold from Holders of the Notes notice of any continuing Default or Event of Default (except a Default or Event of Default relating to the payment of principal or interest or premium, if any,) if it determines that withholding notice is in their interest. The Holders of a majority in aggregate principal amount of the Notes that are then outstanding, by written notice to the Trustee may, on behalf of the Holders of the Notes, rescind an acceleration or waive any existing Default or Event of Default and its consequences under the Indenture except a continuing Default or Event of Default in the payment of interest or premium, if any, on, or the principal of, the Notes. (13) TRUSTEE DEALINGS WITH COMPANY. The Trustee, in its individual or any other capacity, may make loans to, accept deposits from, and perform services for the Company or its Affiliates, and may otherwise deal with the Company or its Affiliates, as if it were not the Trustee. (14) NO RECOURSE AGAINST OTHERS. A director, officer, employee, incorporator or stockholder of the Company or any of the Guarantors, as such, will not have any liability for any obligations of the Company or the Guarantors under the Notes, the Note Guarantees or the Indenture or for any claim based on, in respect of, or by reason of, such obligations or their creation. Each Holder by accepting a Note waives and releases all such liability. The waiver and release are part of the consideration for the issuance of the Notes. (15) AUTHENTICATION. This Note will not be valid until authenticated by the manual signature of the Trustee or an authenticating agent. (16) ABBREVIATIONS. Customary abbreviations may be used in the name of a Holder or an assignee, such as: TEN COM (= tenants in common), TEN ENT (= tenants by the entireties), JT TEN (= joint tenants with right of survivorship and not as tenants in common), CUST (= Custodian), and U/G/M/A (= Uniform Gifts to Minors Act). (17) CUSIP NUMBERS. Pursuant to a recommendation promulgated by the Committee on Uniform Security Identification Procedures, the Company has caused CUSIP numbers to be printed on the Notes, and the Trustee may use CUSIP numbers in notices of redemption as a convenience to Holders. No representation is made as to the accuracy of such numbers either as printed on the Notes or as contained in any notice of redemption, and reliance may be placed only on the other identification numbers placed thereon. (18) GOVERNING LAW. THE INTERNAL LAW OF THE STATE OF NEW YORK WILL GOVERN AND BE USED TO CONSTRUE THE INDENTURE, THIS NOTE AND THE NOTE GUARANTEES WITHOUT GIVING EFFECT TO APPLICABLE PRINCIPLES OF CONFLICTS OF LAW TO THE EXTENT THAT THE APPLICATION OF THE LAWS OF ANOTHER JURISDICTION WOULD BE REQUIRED THEREBY. The Company will furnish to any Holder upon written request and without charge a copy of the Indenture. Requests may be made to: Calpine LLC c/o Constellation Energy Generation, LLC 200 Energy Way Kennett Square, PA, 19348-2473

A-7 Attention: Legal Department Email: legalnotices@constellation.com Telephone: (833) 883-0162 with a copy to (which shall not constitute notice): Ballard Spahr LLP Attention: Patrick R. Gillard, Esq. Telephone: (215) 864-8536 Email: gillard@ballardspahr.com

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1 SUCH THIS NOTE IS A REGISTERED GLOBAL SECURITY WITHIN THE MEANING OF THE INDENTURE HEREINAFTER REFERRED TO AND IS REGISTERED IN THE NAME OF A DEPOSITORY OR A NOMINEE OF A DEPOSITORY OR A SUCCESSOR DEPOSITORY. THIS NOTE IS NOT EXCHANGEABLE FOR SECURITIES REGISTERED IN THE NAME OF A PERSON OTHER THAN THE DEPOSITORY OR ITS NOMINEE EXCEPT IN THE LIMITED CIRCUMSTANCES DESCRIBED IN THE INDENTURE, AND NO TRANSFER OF THIS NOTE (OTHER THAN A TRANSFER OF THIS NOTE AS A WHOLE BY THE DEPOSITORY TO A NOMINEE OF THE DEPOSITORY OR BY A NOMINEE OF THE DEPOSITORY TO THE DEPOSITORY OR ANOTHER NOMINEE OF THE DEPOSITORY) MAY BE REGISTERED EXCEPT IN THE LIMITED CIRCUMSTANCES DESCRIBED IN THE INDENTURE. UNLESS THIS CERTIFICATE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY, A NEW YORK CORPORATION (“DTC”), TO THE ISSUER 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. THIS SECURITY HAS NOT BEEN REGISTERED UNDER THE U.S. SECURITIES ACT OF 1933, AS AMENDED (THE “SECURITIES ACT”), OR THE SECURITIES LAWS OF ANY STATE OROTHER JURISDICTION. NEITHER THIS SECURITY NOR ANY INTEREST OR PARTICIPATION HEREIN MAY BE REOFFERED, SOLD, ASSIGNED, TRANSFERRED, PLEDGED, ENCUMBERED OR OTHERWISE DISPOSED OF IN THE ABSENCE OF SUCH REGISTRATION UNLESS SUCH TRANSACTION IS EXEMPT FROM, OR NOT SUBJECT TO, SUCH REGISTRATION. BY ITS ACQUISITION HEREOF, THE HOLDER AGREES TO OFFER, SELL OR OTHERWISE TRANSFER SUCH SECURITY, PRIOR TO THE DATE (THE “RESALE RESTRICTION TERMINATION DATE”) THAT IS ONE YEAR AFTER THE LATER OF THE ORIGINAL ISSUE DATE HEREOF AND THE LAST DATE ON WHICH THE ISSUER OR ANY AFFILIATE OF THE ISSUER WAS THE OWNER OF THIS SECURITY (OR ANY PREDECESSOR OF SUCH SECURITY), ONLY (A) TO THE ISSUER, (B) PURSUANT TO A REGISTRATION STATEMENT THAT HAS BEEN DECLARED EFFECTIVE UNDER THE SECURITIES ACT, (C) FOR SO LONG AS THE SECURITIES ARE ELIGIBLE FOR RESALE PURSUANT TO RULE 144A UNDER THESECURITIES ACT, TO A PERSON IT REASONABLY BELIEVES IS A “QUALIFIED INSTITUTIONAL BUYER,” AS DEFINED IN RULE 144A UNDER THE SECURITIES ACT, THAT PURCHASES FOR ITS OWN ACCOUNT OR FOR THE ACCOUNT OF A QUALIFIED INSTITUTIONAL BUYER TO WHOM NOTICE IS GIVEN THAT THE TRANSFER IS BEING MADE IN RELIANCE ON RULE 144A, (D) PURSUANT TO, AND IN COMPLIANCE WITH, OFFERS AND SALES THAT OCCUR OUTSIDE THE UNITED STATES TO PERSONS WHO ARE NOT U.S. PERSONS WITHIN THE MEANING OF REGULATION S UNDER THE SECURITIES ACT, (E) PURSUANT TO RULE 144 UNDER THE SECURITIES ACT, OR (F) PURSUANT TO ANY OTHER AVAILABLE EXEMPTION FROM THE REGISTRATION REQUIREMENTS OF THE SECURITIES ACT, SUBJECT TO THE ISSUER’S AND THE TRUSTEE’S RIGHT PRIOR TO

2 ANY SUCH OFFER, SALE OR TRANSFER PURSUANT TO CLAUSE (E) OR (F) TO REQUIRE THE DELIVERY OF AN OPINION OF COUNSEL, CERTIFICATIONS AND/OR OTHER INFORMATION SATISFACTORY TO EACH OF THEM. THIS LEGEND WILL BE REMOVED UPON THE REQUEST OF THE HOLDER AFTER THE RESALE RESTRICTION TERMINATION DATE. BY ITS ACQUISITION HEREOF, THE HOLDER WILL BE DEEMED TO HAVE REPRESENTED AND WARRANTED THAT EITHER (A) NO PORTION OF THE ASSETS USED BY SUCH HOLDER TO ACQUIRE AND HOLD THIS SECURITY CONSTITUTES ASSETS OF AN “EMPLOYEE BENEFIT PLAN” AS DEFINED IN SECTION 3(3) OF THE U.S. EMPLOYEERETIREMENT INCOME SECURITY ACT OF 1974, AS AMENDED (“ERISA”) THAT IS SUBJECTTO TITLE I OF ERISA, OF ANY PLAN, ACCOUNT OR OTHER ARRANGEMENT THAT IS SUBJECT TO SECTION 4975 OF THE U.S. INTERNAL REVENUE CODE OF 1986, AS AMENDED (THE “CODE”) OR ANY PROVISIONS UNDER ANY FEDERAL, STATE, LOCAL, NON-U.S. OR OTHER LAWS OR REGULATIONS THAT ARE SIMILAR TO SUCH PROVISIONS OF ERISA OR THE CODE (“SIMILAR LAWS”), OR OF ANY ENTITY WHOSE UNDERLYING ASSETS ARE CONSIDERED TO INCLUDE “PLAN ASSETS” OF ANY SUCH PLAN, ACCOUNT OR ARRANGEMENT, OR (B) THE PURCHASE AND HOLDING OF THIS SECURITY BY SUCH HOLDER WILL NOT CONSTITUTE A NONEXEMPT PROHIBITED TRANSACTION UNDER SECTION 406 OF ERISA OR SECTION 4975 OF THE CODE OR A VIOLATION UNDER ANY APPLICABLE SIMILAR LAWS. Constellation Energy Generation, LLC 4.625% Senior Notes due February 1, 2029 No. __ $ CUSIP No. 210385AG5 Constellation Energy Generation, LLC, a limited liability company duly organized and subsisting under the laws of the Commonwealth of Pennsylvania (herein called the “Issuer” which term includes any successor Person under the Indenture hereinafter referred to), for value received, hereby promises to pay to Cede & Co., or registered assigns, the principal sum of Dollars ($ ) on February 1, 2029, and to pay interest thereon from August 1, 2025 or from the most recent interest payment date to which interest has been paid or duly provided for, semi-annually on February 1 and August 1 in each year, beginning February 1, 2026 at the rate of 4.625% per annum, until the principal hereof is paid or made available for payment, provided that any principal and premium, and any such installment of interest, which is overdue shall bear interest at the rate of 4.625% per annum (to the extent that the payment of such interest shall be legally enforceable), from the dates such amounts are due until they are paid or made available for payment, and such interest shall be payable on demand. Interest on this Note shall be computed on the basis of a 360-day year composed of twelve 30-day months. The interest so payable, and punctually paid or duly provided for, on any interest payment date will, as provided in such Indenture, be paid to the Person in whose name this Note (or one or more predecessor

3 Securities) is registered at the close of business on the record date for such interest, which shall be January 15 or July 15 (whether or not a Business Day), as the case may be, next preceding such interest payment date. Any such interest not so punctually paid or duly provided for will forthwith cease to be payable to the Holder on such record date and may either be paid to the Person in whose name this Note (or one or more predecessor Securities) is registered at the close of business on a special record date for the payment of such defaulted interest to be fixed by the Trustee, notice whereof shall be given to Holders of Securities of this series not less than 10 days prior to such special record date, or be paid at any time in any other lawful manner not inconsistent with the requirements of any securities exchange on which the Securities of this series may be listed, and upon such notice as may be required by such exchange, all as more fully provided in said Indenture. Payment of the principal of (and premium, if any) and interest on this Note will be made at the office or agency of the Issuer maintained for that purpose in the Borough of Manhattan, the City of New York, in such coin or currency of the United States of America as at the time of payment is legal tender for payment of public and private debts; provided that so long as the Notes are held by DTC as Registered Global Securities, payments shall be made by wire transfer to DTC. Reference is hereby made to the further provisions of this Note set forth on the reverse hereof, which further provisions shall for all purposes have the same effect as if set forth at this place.

[Signature Page to New 2029 Notes] Unless the certificate of authentication hereon has been executed by the Trustee referred to on the reverse hereof, this Note shall not be entitled to any benefit under the Indenture or be valid or obligatory for any purpose. IN WITNESS WHEREOF the Issuer has caused this instrument to be duly executed. Dated: January 15, 2026 CONSTELLATION ENERGY GENERATION, LLC By:_____________________________________ Shane Smith Executive Vice President and Chief Financial Officer Attest: _________________________________________ Brian J. Buck, Assistant Secretary TRUSTEE’S CERTIFICATE OF AUTHENTICATION This is one of the Securities referred to in the within-mentioned Indenture. U.S. Bank Trust Company, National Association, as Trustee By: ____________________________________ Authorized Officer

5 [Reverse of Note] This Note is one of a duly authorized issue of securities of the Issuer (herein called the “Notes”), issued and to be issued in one or more series under an Indenture, dated as of September 28, 2007 (herein called the “Indenture”), between the Issuer (formerly known as Exelon Generation Company, LLC) and U.S. Bank Trust Company, National Association, as successor trustee (herein called the “Trustee”, which term includes any successor trustee under the Indenture), and reference is hereby made to the Indenture, including the Officer’s Certificate, dated as of January 15, 2026 delivered pursuant to Sections 2.1, 2.4(3) and 10.5 of the Indenture and setting forth additional terms of this Note, for a statement of the respective rights, limitations of rights, duties and immunities thereunder of the Issuer, the Trustee and the Holders of the Notes and of the terms upon which the Notes are, and are to be, authenticated and delivered. This Note is one of the series designated on the face hereof, initially limited in aggregate principal amount up to and including $646,822,000. On or after February 1, 2024, the Issuer may on any one or more occasions redeem all or a part of the Notes, upon not less than 10 nor more than 60 days’ notice, at the redemption prices (expressed as percentages of principal amount) set forth below, plus accrued and unpaid interest, if any, on the Notes redeemed, to but excluding the applicable date of redemption, if redeemed during the twelve-month period beginning on February 1 of the years indicated below, subject to the rights of Holders on the relevant record date to receive interest on the relevant interest payment date: Year Percentage 2024............................................................................ 102.313% 2025............................................................................ 101.156% 2026 and thereafter .................................................... 100.000% Unless the Issuer defaults in the payment of the redemption price, interest will cease to accrue on the Notes or portions thereof called for redemption on the applicable redemption date. The Indenture contains provisions for defeasance at any time of the entire indebtedness of this Note or certain restrictive covenants and Events of Default with respect to this Note, in each case upon compliance with certain conditions set forth in the Indenture. If an Event of Default with respect to Notes of this series shall occur and be continuing, the principal of the Notes of this series may be declared due and payable in the manner and with the effect provided in the Indenture. The Indenture permits, with certain exceptions as therein provided, the amendment thereof and the modification of the rights and obligations of the Issuer and the rights of the Holders of the Notes of each series to be affected under the Indenture at any time by the Issuer and the Trustee with the consent of the Holders of a majority in aggregate principal amount of the Notes at the time outstanding of each series to be affected. The Indenture also contains provisions permitting the Holders of specified percentages in principal amount of the Notes of each series at the time outstanding, on behalf of the Holders of all Notes of such series, to waive compliance by the Issuer with certain provisions of the Indenture and certain past defaults under the Indenture and their

6 consequences. Any such consent or waiver by the Holder of this Note shall be conclusive and binding upon such Holder and upon all future Holders of this Note and of any Note issued upon the registration of transfer hereof or in exchange herefor or in lieu hereof, whether or not notation of such consent or waiver is made upon this Note. As provided in and subject to the provisions of the Indenture, the Holder of this Note shall not have the right to institute any proceeding with respect to the Indenture or for the appointment of a receiver or trustee or for any other remedy thereunder, unless such Holder shall have previously given the Trustee written notice of a continuing Event of Default with respect to the Notes of this series, the Holders of not less than 25% in principal amount of the Notes of this series at the time outstanding shall have made written request to the Trustee to institute proceedings in respect of such Event of Default as Trustee and offered the Trustee reasonable indemnity, and the Trustee shall not have received from the Holders of a majority in principal amount of Notes of this series at the time outstanding a direction inconsistent with such request, and shall have failed to institute any such proceeding, for 60 days after receipt of such notice, request and offer of indemnity. The foregoing shall not apply to any suit instituted by the Holder of this Note for the enforcement of any payment of principal hereof or any premium or interest hereon on or after the respective due dates expressed herein. No reference herein to the Indenture and no provision of this Note or of the Indenture shall alter or impair the obligation of the Issuer, which is absolute and unconditional, to pay the principal of and any premium and interest on this Note at the times, place and rate, and in the coin or currency, herein prescribed. As provided in the Indenture and subject to certain limitations therein set forth, the transfer of this Note is registrable in the security register, upon surrender of this Note for registration of transfer at the office or agency of the Issuer in any place where the principal of and any premium and interest on this Note are payable, duly endorsed by, or accompanied by a written instrument of transfer in form satisfactory to the Issuer and the Trustee duly executed, by the Holder hereof or his attorney duly authorized in writing, and thereupon one or more new Notes of this series and of like tenor, of authorized denominations and for the same aggregate principal amount, will be issued to the designated transferee or transferees. The Notes of this series are issuable only in registered form without coupons in denominations of $2,000 and multiples of $1,000 in excess thereof. As provided in the Indenture and subject to certain limitations therein set forth, Notes of this series are exchangeable for a like aggregate principal amount of Notes of this series and of like tenor of a different authorized denomination, as requested in writing by the Holder surrendering the same. No service charge shall be made for any such registration of transfer or exchange, but the Issuer may require payment of a sum sufficient to cover any tax or other governmental charge payable in connection therewith. Prior to due presentment of this Note for registration of transfer and notice to the Trustee thereof the Issuer, the Trustee and any agent of the Issuer or the Trustee may treat the Person in whose name this Note is registered as the owner hereof for all purposes, whether or not this Note

7 be overdue, and neither the issuer, the Trustee nor any such agent shall be affected by notice to the contrary. The Issuer may deliver its signature page to this Note, and the Trustee may validly authenticate this Note, by manual, facsimile, or Electronic Signature, in each case which may be delivered by telecopier, facsimile or other electronic transmission (e.g. a “pdf” or “tif”), which shall be effective as delivery of a manually signature thereof and may be used in lieu of manual signature pages for all purposes. This Note shall not be valid until authenticated by the manual signature, facsimile, or Electronic Signature of the Trustee or an authenticating agent in accordance with the Indenture. An authenticating agent may authenticate Notes whenever the Trustee may do so. As used herein, “Electronic Signature” means any electronic signature covered by the Electronic Signatures in Global and National Commerce Act of 2000, Uniform Electronic Transactions Act, the Electronic Signatures and Records Act or other applicable law (e.g., www.docusign.com). Notwithstanding Section 2.5 of the Indenture, the Notes will not be required to be signed under the Issuer’s seal. THE INDENTURE AND THIS NOTE SHALL BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE COMMONWEALTH OF PENNSYLVANIA WITHOUT GIVING EFFECT TO PRINCIPLES OF CONFLICTS OF LAW. All terms used in this Note, which are not otherwise defined herein, but are defined in the Indenture shall have the meanings assigned to them in the Indenture.

9 ASSIGNMENT FORM If you, the holder, want to assign this Note, fill in the form below and have your signature guaranteed: I or we assign and transfer this Note to (Insert assignee’s social security or tax ID number) (Print or type assignee’s name, address and zip code) and irrevocably appoint agent to transfer this Note on the books of the Issuer. The agent may substitute another to act for such agent. Date: Your Signature: (Sign exactly as your name appears on the other side of this Note) By: NOTICE: To be executed by an executive officer Signature Guarantee:

10 SCHEDULE OF INCREASES OR DECREASES IN REGISTERED GLOBAL SECURITY The following increases or decreases in this Registered Global Security have been made: Date of Exchange Amount of decrease in Principal Amount of this Global Registered Security Amount of Increase in Principal Amount of this Global Registered Security Principal Amount of this Registered Global Security following such decrease or increase Signature of authorized officer of Trustee or Securities Custodian

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THIS NOTE IS A REGISTERED GLOBAL SECURITY WITHIN THE MEANING OF THE INDENTURE HEREINAFTER REFERRED TO AND IS REGISTERED IN THE NAME OF A DEPOSITORY OR A NOMINEE OF A DEPOSITORY OR A SUCCESSOR DEPOSITORY. THIS NOTE IS NOT EXCHANGEABLE FOR SECURITIES REGISTERED IN THE NAME OF A PERSON OTHER THAN THE DEPOSITORY OR ITS NOMINEE EXCEPT IN THE LIMITED CIRCUMSTANCES DESCRIBED IN THE INDENTURE, AND NO TRANSFER OF THIS NOTE (OTHER THAN A TRANSFER OF THIS NOTE AS A WHOLE BY THE DEPOSITORY TO A NOMINEE OF THE DEPOSITORY OR BY A NOMINEE OF THE DEPOSITORY TO THE DEPOSITORY OR ANOTHER NOMINEE OF THE DEPOSITORY) MAY BE REGISTERED EXCEPT IN THE LIMITED CIRCUMSTANCES DESCRIBED IN THE INDENTURE. UNLESS THIS CERTIFICATE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY, A NEW YORK CORPORATION (“DTC”), TO THE ISSUER 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. THIS SECURITY HAS NOT BEEN REGISTERED UNDER THE U.S. SECURITIES ACT OF 1933,AS AMENDED (THE “SECURITIES ACT”), OR THE SECURITIES LAWS OF ANY STATE OROTHER JURISDICTION. NEITHER THIS SECURITY NOR ANY INTEREST OR PARTICIPATION HEREIN MAY BE REOFFERED, SOLD, ASSIGNED, TRANSFERRED, PLEDGED, ENCUMBERED OR OTHERWISE DISPOSED OF IN THE ABSENCE OF SUCH REGISTRATION UNLESS SUCH TRANSACTION IS EXEMPT FROM, OR NOT SUBJECT TO, SUCH REGISTRATION. BY ITS ACQUISITION HEREOF, THE HOLDER AGREES TO OFFER, SELL OR OTHERWISE TRANSFER SUCH SECURITY, PRIOR TO THE DATE (THE “RESALE RESTRICTION TERMINATION DATE”) THAT IS ONE YEAR AFTER THE LATER OF THE ORIGINAL ISSUE DATE HEREOF AND THE LAST DATE ON WHICH THE ISSUER OR ANY AFFILIATE OF THE ISSUER WAS THE OWNER OF THIS SECURITY (OR ANY PREDECESSOR OF SUCH SECURITY), ONLY (A) TO THE ISSUER, (B) PURSUANT TO A REGISTRATION STATEMENT THAT HAS BEEN DECLARED EFFECTIVE UNDER THE SECURITIES ACT, (C) FOR SO LONG AS THE SECURITIES ARE ELIGIBLE FOR RESALE PURSUANT TO RULE 144A UNDER THE SECURITIES ACT, TO A PERSON IT REASONABLY BELIEVES IS A “QUALIFIED INSTITUTIONAL BUYER,” AS DEFINED IN RULE 144A UNDER THE SECURITIES ACT, THAT PURCHASES FOR ITS OWN ACCOUNT OR FOR THE ACCOUNT OF A QUALIFIED INSTITUTIONAL BUYER TO WHOM NOTICE IS GIVEN THAT THE TRANSFER IS BEING MADE IN RELIANCE ON RULE 144A, (D) PURSUANT TO, AND IN COMPLIANCE WITH, OFFERS AND SALES THAT OCCUR OUTSIDE THE UNITED STATES TO PERSONS WHO ARE NOT U.S. PERSONS WITHIN THE MEANING OF REGULATION S UNDER THE SECURITIES ACT, (E) PURSUANT TO RULE 144 UNDER THE SECURITIES ACT, OR (F) PURSUANT TO ANY OTHER AVAILABLE EXEMPTION FROM THE REGISTRATION REQUIREMENTS OF THE

1 SECURITIES ACT, SUBJECT TO THE ISSUER’S AND THE TRUSTEE’S RIGHT PRIOR TO ANY SUCH OFFER, SALE OR TRANSFER PURSUANT TO CLAUSE (E) OR (F) TO REQUIRE THE DELIVERY OF AN OPINION OF COUNSEL, CERTIFICATIONS AND/OR OTHER INFORMATION SATISFACTORY TO EACH OF THEM. THIS LEGEND WILL BE REMOVED UPON THE REQUEST OF THE HOLDER AFTER THE RESALE RESTRICTION TERMINATION DATE. BY ITS ACQUISITION HEREOF, THE HOLDER WILL BE DEEMED TO HAVE REPRESENTED AND WARRANTED THAT EITHER (A) NO PORTION OF THE ASSETS USED BY SUCH HOLDER TO ACQUIRE AND HOLD THIS SECURITY CONSTITUTES ASSETS OF AN “EMPLOYEE BENEFIT PLAN” AS DEFINED IN SECTION 3(3) OF THE U.S. EMPLOYEERETIREMENT INCOME SECURITY ACT OF 1974, AS AMENDED (“ERISA”) THAT IS SUBJECTTO TITLE I OF ERISA, OF ANY PLAN, ACCOUNT OR OTHER ARRANGEMENT THAT IS SUBJECT TO SECTION 4975 OF THE U.S. INTERNAL REVENUE CODE OF 1986, AS AMENDED (THE “CODE”) OR ANY PROVISIONS UNDER ANY FEDERAL, STATE, LOCAL, NON-U.S. OR OTHER LAWS OR REGULATIONS THAT ARE SIMILAR TO SUCH PROVISIONS OF ERISA OR THE CODE (“SIMILAR LAWS”), OR OF ANY ENTITY WHOSE UNDERLYING ASSETS ARE CONSIDERED TO INCLUDE “PLAN ASSETS” OF ANY SUCH PLAN, ACCOUNT OR ARRANGEMENT, OR (B) THE PURCHASE AND HOLDING OF THIS SECURITY BY SUCH HOLDER WILL NOT CONSTITUTE A NONEXEMPT PROHIBITED TRANSACTION UNDER SECTION 406 OF ERISA OR SECTION 4975 OF THE CODE OR A VIOLATION UNDER ANY APPLICABLE SIMILAR LAWS. Constellation Energy Generation, LLC 5.000% Senior Notes due February 1, 2031 No. $ CUSIP No. 210385AJ9 Constellation Energy Generation, LLC, a limited liability company duly organized and subsisting under the laws of the Commonwealth of Pennsylvania (herein called the “Issuer” which term includes any successor Person under the Indenture hereinafter referred to), for value received, hereby promises to pay to Cede & Co., or registered assigns, the principal sum of Dollars ($ ) on February 1, 2031, and to pay interest thereon from August 1, 2025 or from the most recent interest payment date to which interest has been paid or duly provided for, semi-annually on February 1 and August 1 in each year, beginning February 1, 2026 at the rate of 5.000% per annum, until the principal hereof is paid or made available for payment, provided that any principal and premium, and any such installment of interest, which is overdue shall bear interest at the rate of 5.000% per annum (to the extent that the payment of such interest shall be legally enforceable), from the dates such amounts are due until they are paid or made available for payment, and such interest shall be payable on demand. Interest on this Note shall be computed on the basis of a 360-day year composed of twelve 30-day months. The interest so payable, and punctually paid or duly provided for, on any interest payment date will, as provided in such

2 Indenture, be paid to the Person in whose name this Note (or one or more predecessor Securities) is registered at the close of business on the record date for such interest, which shall be January 15 or July 15 (whether or not a Business Day), as the case may be, next preceding such interest payment date. Any such interest not so punctually paid or duly provided for will forthwith cease to be payable to the Holder on such record date and may either be paid to the Person in whose name this Note (or one or more predecessor Securities) is registered at the close of business on a special record date for the payment of such defaulted interest to be fixed by the Trustee, notice whereof shall be given to Holders of Securities of this series not less than 10 days prior to such special record date, or be paid at any time in any other lawful manner not inconsistent with the requirements of any securities exchange on which the Securities of this series may be listed, and upon such notice as may be required by such exchange, all as more fully provided in said Indenture. Payment of the principal of (and premium, if any) and interest on this Note will be made at the office or agency of the Issuer maintained for that purpose in the Borough of Manhattan, the City of New York, in such coin or currency of the United States of America as at the time of payment is legal tender for payment of public and private debts; provided that so long as the Notes are held by DTC as Registered Global Securities, payments shall be made by wire transfer to DTC. Reference is hereby made to the further provisions of this Note set forth on the reverse hereof, which further provisions shall for all purposes have the same effect as if set forth at this place.

[Signature Page to New Feb 2031 Notes] Unless the certificate of authentication hereon has been executed by the Trustee referred to on the reverse hereof, this Note shall not be entitled to any benefit under the Indenture or be valid or obligatory for any purpose. IN WITNESS WHEREOF the Issuer has caused this instrument to be duly executed. Dated: January 15, 2026 CONSTELLATION ENERGY GENERATION, LLC By:_____________________________________ Shane Smith Executive Vice President and Chief Financial Officer Attest: _________________________________________ Brian J. Buck, Assistant Secretary TRUSTEE’S CERTIFICATE OF AUTHENTICATION This is one of the Securities referred to in the within-mentioned Indenture. U.S. Bank Trust Company, National Association, as Trustee By: ____________________________________ Authorized Officer

4 [Reverse of Note] This Note is one of a duly authorized issue of securities of the Issuer (herein called the “Notes”), issued and to be issued in one or more series under an Indenture, dated as of September 28, 2007 (herein called the “Indenture”), between the Issuer (formerly known as Exelon Generation Company, LLC) and U.S. Bank Trust Company, National Association, as successor trustee (herein called the “Trustee”, which term includes any successor trustee under the Indenture), and reference is hereby made to the Indenture, including the Officer’s Certificate, dated as of January 15, 2026 delivered pursuant to Sections 2.1, 2.4(3) and 10.5 of the Indenture and setting forth additional terms of this Note, for a statement of the respective rights, limitations of rights, duties and immunities thereunder of the Issuer, the Trustee and the Holders of the Notes and of the terms upon which the Notes are, and are to be, authenticated and delivered. This Note is one of the series designated on the face hereof, initially limited in aggregate principal amount up to and including $847,657,170. At any time prior to February 1, 2027, the Issuer may on any one or more occasions redeem all or a part of the Notes, upon not less than 10 nor more than 60 days’ notice, at a redemption price equal to 100% of the principal amount of the Notes redeemed, plus the Applicable Premium as of, and accrued and unpaid interest, if any, to but excluding the date of redemption, subject to the rights of Holders on the relevant record date to receive interest due on the relevant interest payment date. On or after February 1, 2027, the Company may on any one or more occasions redeem all or a part of the Notes, upon not less than 10 nor more than 60 days’ notice, at the redemption prices (expressed as percentages of principal amount) set forth below, plus accrued and unpaid interest, if any, on the Notes redeemed, to but excluding the applicable date of redemption, if redeemed during the twelve-month period beginning on February 1 of the years indicated below, subject to the rights of Holders on the relevant record date to receive interest on the relevant interest payment date: Year Percentage 2027............................................................................ 101.667% 2028............................................................................ 100.833% 2029 and thereafter .................................................... 100.000% Unless the Company defaults in the payment of the redemption price, interest will cease to accrue on the Notes or portions thereof called for redemption on the applicable redemption date. “Applicable Premium” means, with respect to any Note on any redemption date, as calculated by us, the greater of: (1) 1.0% of the principal amount of the Note; or (2) the excess of: (a)the present value at such redemption date of (i) the redemption price of the Note at February 1, 2027 (such redemption price being set forth in the table appearing above) plus (ii) all required interest payments due on the Note through February 1, 2027 (excluding accrued but unpaid interest to the redemption date),

5 computed using a discount rate equal to the Treasury Rate as of such redemption date plus 75 basis points; over (b) the principal amount of the Note. “Treasury Rate” means, as of any redemption date, the yield to maturity as of such redemption date of United States Treasury securities with a constant maturity (as compiled and published in the most recent Federal Reserve Statistical Release H.15 (519) that has become publicly available at least two business days prior to the redemption date (or, if such Statistical Release is no longer published, any publicly available source of similar market data)) most nearly equal to the period from the redemption date to February 1, 2027; provided, however, that if the period from the redemption date to February 1, 2027 is less than one year, the weekly average yield on actively traded United States Treasury securities adjusted to a constant maturity of one year will be used. The Indenture contains provisions for defeasance at any time of the entire indebtedness of this Note or certain restrictive covenants and Events of Default with respect to this Note, in each case upon compliance with certain conditions set forth in the Indenture. If an Event of Default with respect to Notes of this series shall occur and be continuing, the principal of the Notes of this series may be declared due and payable in the manner and with the effect provided in the Indenture. The Indenture permits, with certain exceptions as therein provided, the amendment thereof and the modification of the rights and obligations of the Issuer and the rights of the Holders of the Notes of each series to be affected under the Indenture at any time by the Issuer and the Trustee with the consent of the Holders of a majority in aggregate principal amount of the Notes at the time outstanding of each series to be affected. The Indenture also contains provisions permitting the Holders of specified percentages in principal amount of the Notes of each series at the time outstanding, on behalf of the Holders of all Notes of such series, to waive compliance by the Issuer with certain provisions of the Indenture and certain past defaults under the Indenture and their consequences. Any such consent or waiver by the Holder of this Note shall be conclusive and binding upon such Holder and upon all future Holders of this Note and of any Note issued upon the registration of transfer hereof or in exchange herefor or in lieu hereof, whether or not notation of such consent or waiver is made upon this Note. As provided in and subject to the provisions of the Indenture, the Holder of this Note shall not have the right to institute any proceeding with respect to the Indenture or for the appointment of a receiver or trustee or for any other remedy thereunder, unless such Holder shall have previously given the Trustee written notice of a continuing Event of Default with respect to the Notes of this series, the Holders of not less than 25% in principal amount of the Notes of this series at the time outstanding shall have made written request to the Trustee to institute proceedings in respect of such Event of Default as Trustee and offered the Trustee reasonable indemnity, and the Trustee shall not have received from the Holders of a majority in principal amount of Notes of this series at the time outstanding a direction inconsistent with such request, and shall have failed to institute any such proceeding, for 60 days after receipt of such notice, request and offer of indemnity. The foregoing shall not apply to any suit instituted by the Holder of this Note for the

6 enforcement of any payment of principal hereof or any premium or interest hereon on or after the respective due dates expressed herein. No reference herein to the Indenture and no provision of this Note or of the Indenture shall alter or impair the obligation of the Issuer, which is absolute and unconditional, to pay the principal of and any premium and interest on this Note at the times, place and rate, and in the coin or currency, herein prescribed. As provided in the Indenture and subject to certain limitations therein set forth, the transfer of this Note is registrable in the security register, upon surrender of this Note for registration of transfer at the office or agency of the Issuer in any place where the principal of and any premium and interest on this Note are payable, duly endorsed by, or accompanied by a written instrument of transfer in form satisfactory to the Issuer and the Trustee duly executed, by the Holder hereof or his attorney duly authorized in writing, and thereupon one or more new Notes of this series and of like tenor, of authorized denominations and for the same aggregate principal amount, will be issued to the designated transferee or transferees. The Notes of this series are issuable only in registered form without coupons in denominations of $2,000 and multiples of $1,000 in excess thereof. As provided in the Indenture and subject to certain limitations therein set forth, Notes of this series are exchangeable for a like aggregate principal amount of Notes of this series and of like tenor of a different authorized denomination, as requested in writing by the Holder surrendering the same. No service charge shall be made for any such registration of transfer or exchange, but the Issuer may require payment of a sum sufficient to cover any tax or other governmental charge payable in connection therewith. Prior to due presentment of this Note for registration of transfer and notice to the Trustee thereof the Issuer, the Trustee and any agent of the Issuer or the Trustee may treat the Person in whose name this Note is registered as the owner hereof for all purposes, whether or not this Note be overdue, and neither the issuer, the Trustee nor any such agent shall be affected by notice to the contrary. The Issuer may deliver its signature page to this Note, and the Trustee may validly authenticate this Note, by manual, facsimile, or Electronic Signature, in each case which may be delivered by telecopier, facsimile or other electronic transmission (e.g. a “pdf” or “tif”), which shall be effective as delivery of a manually signature thereof and may be used in lieu of manual signature pages for all purposes. This Note shall not be valid until authenticated by the manual signature, facsimile, or Electronic Signature of the Trustee or an authenticating agent in accordance with the Indenture. An authenticating agent may authenticate Notes whenever the Trustee may do so. As used herein, “Electronic Signature” means any electronic signature covered by the Electronic Signatures in Global and National Commerce Act of 2000, Uniform Electronic Transactions Act, the Electronic Signatures and Records Act or other applicable law (e.g., www.docusign.com).

7 Notwithstanding Section 2.5 of the Indenture, the Notes will not be required to be signed under the Issuer’s seal. THE INDENTURE AND THIS NOTE SHALL BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE COMMONWEALTH OF PENNSYLVANIA WITHOUT GIVING EFFECT TO PRINCIPLES OF CONFLICTS OF LAW. All terms used in this Note, which are not otherwise defined herein, but are defined in the Indenture shall have the meanings assigned to them in the Indenture.

8 ASSIGNMENT FORM If you, the holder, want to assign this Note, fill in the form below and have your signature guaranteed: I or we assign and transfer this Note to (Insert assignee’s social security or tax ID number) (Print or type assignee’s name, address and zip code) and irrevocably appoint agent to transfer this Note on the books of the Issuer. The agent may substitute another to act for such agent. Date: Your Signature: (Sign exactly as your name appears on the other side of this Note) By: NOTICE: To be executed by an executive officer Signature Guarantee:

9 SCHEDULE OF INCREASES OR DECREASES IN REGISTERED GLOBAL SECURITY The following increases or decreases in this Registered Global Security have been made: Date of Exchange Amount of decrease in Principal Amount of this Global Registered Security Amount of Increase in Principal Amount of this Global Registered Security Principal Amount of this Registered Global Security following such decrease or increase Signature of authorized officer of Trustee or Securities Custodian

ceg-202601158kexh46

THIS NOTE IS A REGISTERED GLOBAL SECURITY WITHIN THE MEANING OF THE INDENTURE HEREINAFTER REFERRED TO AND IS REGISTERED IN THE NAME OF A DEPOSITORY OR A NOMINEE OF A DEPOSITORY OR A SUCCESSOR DEPOSITORY. THIS NOTE IS NOT EXCHANGEABLE FOR SECURITIES REGISTERED IN THE NAME OF A PERSON OTHER THAN THE DEPOSITORY OR ITS NOMINEE EXCEPT IN THE LIMITED CIRCUMSTANCES DESCRIBED IN THE INDENTURE, AND NO TRANSFER OF THIS NOTE (OTHER THAN A TRANSFER OF THIS NOTE AS A WHOLE BY THE DEPOSITORY TO A NOMINEE OF THE DEPOSITORY OR BY A NOMINEE OF THE DEPOSITORY TO THE DEPOSITORY OR ANOTHER NOMINEE OF THE DEPOSITORY) MAY BE REGISTERED EXCEPT IN THE LIMITED CIRCUMSTANCES DESCRIBED IN THE INDENTURE. UNLESS THIS CERTIFICATE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY, A NEW YORK CORPORATION (“DTC”), TO THE ISSUER 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. THIS SECURITY HAS NOT BEEN REGISTERED UNDER THE U.S. SECURITIES ACT OF 1933,AS AMENDED (THE “SECURITIES ACT”), OR THE SECURITIES LAWS OF ANY STATE OROTHER JURISDICTION. NEITHER THIS SECURITY NOR ANY INTEREST OR PARTICIPATION HEREIN MAY BE REOFFERED, SOLD, ASSIGNED, TRANSFERRED, PLEDGED, ENCUMBERED OR OTHERWISE DISPOSED OF IN THE ABSENCE OF SUCH REGISTRATION UNLESS SUCH TRANSACTION IS EXEMPT FROM, OR NOT SUBJECT TO, SUCH REGISTRATION. BY ITS ACQUISITION HEREOF, THE HOLDER AGREES TO OFFER, SELL OR OTHERWISE TRANSFER SUCH SECURITY, PRIOR TO THE DATE (THE “RESALE RESTRICTION TERMINATION DATE”) THAT IS ONE YEAR AFTER THE LATER OF THE ORIGINAL ISSUE DATE HEREOF AND THE LAST DATE ON WHICH THE ISSUER OR ANY AFFILIATE OF THE ISSUER WAS THE OWNER OF THIS SECURITY (OR ANY PREDECESSOR OF SUCH SECURITY), ONLY (A) TO THE ISSUER, (B) PURSUANT TO A REGISTRATION STATEMENT THAT HAS BEEN DECLARED EFFECTIVE UNDER THE SECURITIES ACT, (C) FOR SO LONG AS THE SECURITIES ARE ELIGIBLE FOR RESALE PURSUANT TO RULE 144A UNDER THESECURITIES ACT, TO A PERSON IT REASONABLY BELIEVES IS A “QUALIFIED INSTITUTIONAL BUYER,” AS DEFINED IN RULE 144A UNDER THE SECURITIES ACT, THAT PURCHASES FOR ITS OWN ACCOUNT OR FOR THE ACCOUNT OF A QUALIFIED INSTITUTIONAL BUYER TO WHOM NOTICE IS GIVEN THAT THE TRANSFER IS BEING MADE IN RELIANCE ON RULE 144A, (D) PURSUANT TO, AND IN COMPLIANCE WITH, OFFERS AND SALES THAT OCCUR OUTSIDE THE UNITED STATES TO PERSONS WHO ARE NOT U.S. PERSONS WITHIN THE MEANING OF REGULATION S UNDER THE SECURITIES ACT, (E) PURSUANT TO RULE 144 UNDER THE SECURITIES ACT, OR (F) PURSUANT TO ANY OTHER AVAILABLE EXEMPTION FROM THE REGISTRATION REQUIREMENTS OF THE SECURITIES ACT, SUBJECT TO THE ISSUER’S AND THE TRUSTEE’S RIGHT PRIOR TO

ANY SUCH OFFER, SALE OR TRANSFER PURSUANT TO CLAUSE (E) OR (F) TO REQUIRE THE DELIVERY OF AN OPINION OF COUNSEL, CERTIFICATIONS AND/OR OTHER INFORMATION SATISFACTORY TO EACH OF THEM. THIS LEGEND WILL BE REMOVED UPON THE REQUEST OF THE HOLDER AFTER THE RESALE RESTRICTION TERMINATION DATE. BY ITS ACQUISITION HEREOF, THE HOLDER WILL BE DEEMED TO HAVE REPRESENTED AND WARRANTED THAT EITHER (A) NO PORTION OF THE ASSETS USED BY SUCH HOLDER TO ACQUIRE AND HOLD THIS SECURITY CONSTITUTES ASSETS OF AN “EMPLOYEE BENEFIT PLAN” AS DEFINED IN SECTION 3(3) OF THE U.S. EMPLOYEERETIREMENT INCOME SECURITY ACT OF 1974, AS AMENDED (“ERISA”) THAT IS SUBJECTTO TITLE I OF ERISA, OF ANY PLAN, ACCOUNT OR OTHER ARRANGEMENT THAT IS SUBJECT TO SECTION 4975 OF THE U.S. INTERNAL REVENUE CODE OF 1986, AS AMENDED (THE “CODE”) OR ANY PROVISIONS UNDER ANY FEDERAL, STATE, LOCAL, NON-U.S. OR OTHER LAWS OR REGULATIONS THAT ARE SIMILAR TO SUCH PROVISIONS OF ERISA OR THE CODE (“SIMILAR LAWS”), OR OF ANY ENTITY WHOSE UNDERLYING ASSETS ARE CONSIDERED TO INCLUDE “PLAN ASSETS” OF ANY SUCH PLAN, ACCOUNT OR ARRANGEMENT, OR (B) THE PURCHASE AND HOLDING OF THIS SECURITY BY SUCH HOLDER WILL NOT CONSTITUTE A NONEXEMPT PROHIBITED TRANSACTION UNDER SECTION 406 OF ERISA OR SECTION 4975 OF THE CODE OR A VIOLATION UNDER ANY APPLICABLE SIMILAR LAWS. Constellation Energy Generation, LLC 3.750% Senior Notes due March 1, 2031 No. $ CUSIP No. 210385AL4 Constellation Energy Generation, LLC, a limited liability company duly organized and subsisting under the laws of the Commonwealth of Pennsylvania (herein called the “Issuer” which term includes any successor Person under the Indenture hereinafter referred to), for value received, hereby promises to pay to Cede & Co., or registered assigns, the principal sum of Dollars ($ ) on March 1, 2031, and to pay interest thereon from September 1, 2025 or from the most recent interest payment date to which interest has been paid or duly provided for, semi-annually on March 1 and September 1 in each year, beginning March 1, 2026 at the rate of 3.750% per annum, until the principal hereof is paid or made available for payment, provided that any principal and premium, and any such installment of interest, which is overdue shall bear interest at the rate of 3.750% per annum (to the extent that the payment of such interest shall be legally enforceable), from the dates such amounts are due until they are paid or made available for payment, and such interest shall be payable on demand. Interest on this Note shall be computed on the basis of a 360-day year composed of twelve 30-day months. The interest so payable, and punctually paid or duly provided for, on any interest payment date will, as provided in such Indenture, be paid to the Person in whose name this Note (or one or more predecessor Securities)

is registered at the close of business on the record date for such interest, which shall be February 15 or August 15 (whether or not a Business Day), as the case may be, next preceding such interest payment date. Any such interest not so punctually paid or duly provided for will forthwith cease to be payable to the Holder on such record date and may either be paid to the Person in whose name this Note (or one or more predecessor Securities) is registered at the close of business on a special record date for the payment of such defaulted interest to be fixed by the Trustee, notice whereof shall be given to Holders of Securities of this series not less than 10 days prior to such special record date, or be paid at any time in any other lawful manner not inconsistent with the requirements of any securities exchange on which the Securities of this series may be listed, and upon such notice as may be required by such exchange, all as more fully provided in said Indenture. Payment of the principal of (and premium, if any) and interest on this Note will be made at the office or agency of the Issuer maintained for that purpose in the Borough of Manhattan, the City of New York, in such coin or currency of the United States of America as at the time of payment is legal tender for payment of public and private debts; provided that so long as the Notes are held by DTC as Registered Global Securities, payments shall be made by wire transfer to DTC. Reference is hereby made to the further provisions of this Note set forth on the reverse hereof, which further provisions shall for all purposes have the same effect as if set forth at this place.

[Signature Page to New Mar 2031 Notes] Unless the certificate of authentication hereon has been executed by the Trustee referred to on the reverse hereof, this Note shall not be entitled to any benefit under the Indenture or be valid or obligatory for any purpose. IN WITNESS WHEREOF the Issuer has caused this instrument to be duly executed. Dated: January 15, 2026 CONSTELLATION ENERGY GENERATION, LLC By:_____________________________________ Shane Smith Executive Vice President and Chief Financial Officer Attest: _________________________________________ Brian J. Buck, Assistant Secretary TRUSTEE’S CERTIFICATE OF AUTHENTICATION This is one of the Securities referred to in the within-mentioned Indenture. U.S. Bank Trust Company, National Association, as Trustee By: ____________________________________ Authorized Officer

5 [Reverse of Note] This Note is one of a duly authorized issue of securities of the Issuer (herein called the “Notes”), issued and to be issued in one or more series under an Indenture, dated as of September 28, 2007 (herein called the “Indenture”), between the Issuer (formerly known as Exelon Generation Company, LLC) and U.S. Bank Trust Company, National Association, as successor trustee (herein called the “Trustee”, which term includes any successor trustee under the Indenture), and reference is hereby made to the Indenture, including the Officer’s Certificate, dated as of January 15, 2026 delivered pursuant to Sections 2.1, 2.4(3) and 10.5 of the Indenture and setting forth additional terms of this Note, for a statement of the respective rights, limitations of rights, duties and immunities thereunder of the Issuer, the Trustee and the Holders of the Notes and of the terms upon which the Notes are, and are to be, authenticated and delivered. This Note is one of the series designated on the face hereof, initially limited in aggregate principal amount up to and including $795,179,800. At any time prior to December 1, 2030 (the “Par Call Date”), the Issuer may redeem the Notes in whole or in part, at the Issuer’s option 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 thereon discounted to the redemption date (assuming such Notes matured on the applicable Par Call Date) on a semi-annual basis (assuming a 360-day year consisting of twelve 30-day months) at the Treasury Rate (defined below) plus 75 basis points, and in each case, less (b) interest accrued to the date of redemption; and (2) 100% of the principal amount of the Notes then outstanding to be redeemed, plus, in each case, accrued and unpaid interest thereon to but excluding the redemption date. On or after the applicable Par Call Date, the Issuer may redeem the Notes, in whole or in part, at any time and from time to time, at a redemption price equal to 100% of the principal amount of the notes being redeemed plus accrued and unpaid interest thereon to but excluding the redemption date. “Treasury Rate” means, with respect to any redemption date, the yield determined by the Issuer in accordance with the following two paragraphs. The Treasury Rate shall be determined by the Issuer 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 Issuer shall select, as applicable: (1) the yield for the Treasury constant maturity on H.15 exactly equal to the period from the redemption date to the Par Call Date (the “Remaining Life”); or (2) if there is no such Treasury constant maturity on H.15 exactly equal to the Remaining Life, the two yields – one yield corresponding to the Treasury constant maturity on H.15 immediately shorter than and one yield corresponding to the Treasury constant maturity on H.15

6 immediately longer than the Remaining Life – and shall interpolate to the Par Call Date on a straight-line basis (using the actual number of days) using such yields and rounding the result to three decimal places; or (3) if there is no such Treasury constant maturity on H.15 shorter than or longer than the Remaining Life, the yield for the single Treasury constant maturity on H.15 closest to the Remaining Life. For purposes of this paragraph, the applicable Treasury constant maturity or maturities on H.15 shall be deemed to have a maturity date equal to the relevant number of months or years, as applicable, of such Treasury constant maturity from the redemption date. If on the third business day preceding the redemption date H.15 TCM is no longer published, the Issuer shall calculate the Treasury Rate based on the rate per annum equal to the semi-annual equivalent yield to maturity at 11:00 a.m., New York City time, on the second business day preceding such redemption date of the United States Treasury security maturing on, or with a maturity that is closest to, the Par Call Date, as applicable. If there is no United States Treasury security maturing on the Par Call Date but there are two or more United States Treasury securities with a maturity date equally distant from the Par Call Date, one with a maturity date preceding the Par Call Date and one with a maturity date following the Par Call Date, the Issuer shall select the United States Treasury security with a maturity date preceding the Par Call Date. If there are two or more United States Treasury securities maturing on the Par Call Date or two or more United States Treasury securities meeting the criteria of the preceding sentence, the Issuer 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 Issuer will provide notice of any redemption at least 10 days but not more than 60 days before the redemption date to each holder of Notes to be redeemed. Unless the Issuer defaults in payment of the redemption price, on and after the redemption date interest will cease to accrue on the Notes or portions thereof called for redemption. The Indenture contains provisions for defeasance at any time of the entire indebtedness of this Note or certain restrictive covenants and Events of Default with respect to this Note, in each case upon compliance with certain conditions set forth in the Indenture. If an Event of Default with respect to Notes of this series shall occur and be continuing, the principal of the Notes of this series may be declared due and payable in the manner and with the effect provided in the Indenture. The Indenture permits, with certain exceptions as therein provided, the amendment thereof and the modification of the rights and obligations of the Issuer and the rights of the Holders of the Notes of each series to be affected under the Indenture at any time by the Issuer and the Trustee with the consent of the Holders of a majority in aggregate principal amount of the Notes at the time outstanding of each series to be affected. The Indenture also contains provisions permitting the Holders of specified percentages in principal amount of the Notes of each series at the time

7 outstanding, on behalf of the Holders of all Notes of such series, to waive compliance by the Issuer with certain provisions of the Indenture and certain past defaults under the Indenture and their consequences. Any such consent or waiver by the Holder of this Note shall be conclusive and binding upon such Holder and upon all future Holders of this Note and of any Note issued upon the registration of transfer hereof or in exchange herefor or in lieu hereof, whether or not notation of such consent or waiver is made upon this Note. As provided in and subject to the provisions of the Indenture, the Holder of this Note shall not have the right to institute any proceeding with respect to the Indenture or for the appointment of a receiver or trustee or for any other remedy thereunder, unless such Holder shall have previously given the Trustee written notice of a continuing Event of Default with respect to the Notes of this series, the Holders of not less than 25% in principal amount of the Notes of this series at the time outstanding shall have made written request to the Trustee to institute proceedings in respect of such Event of Default as Trustee and offered the Trustee reasonable indemnity, and the Trustee shall not have received from the Holders of a majority in principal amount of Notes of this series at the time outstanding a direction inconsistent with such request, and shall have failed to institute any such proceeding, for 60 days after receipt of such notice, request and offer of indemnity. The foregoing shall not apply to any suit instituted by the Holder of this Note for the enforcement of any payment of principal hereof or any premium or interest hereon on or after the respective due dates expressed herein. No reference herein to the Indenture and no provision of this Note or of the Indenture shall alter or impair the obligation of the Issuer, which is absolute and unconditional, to pay the principal of and any premium and interest on this Note at the times, place and rate, and in the coin or currency, herein prescribed. As provided in the Indenture and subject to certain limitations therein set forth, the transfer of this Note is registrable in the security register, upon surrender of this Note for registration of transfer at the office or agency of the Issuer in any place where the principal of and any premium and interest on this Note are payable, duly endorsed by, or accompanied by a written instrument of transfer in form satisfactory to the Issuer and the Trustee duly executed, by the Holder hereof or his attorney duly authorized in writing, and thereupon one or more new Notes of this series and of like tenor, of authorized denominations and for the same aggregate principal amount, will be issued to the designated transferee or transferees. The Notes of this series are issuable only in registered form without coupons in denominations of $2,000 and multiples of $1,000 in excess thereof. As provided in the Indenture and subject to certain limitations therein set forth, Notes of this series are exchangeable for a like aggregate principal amount of Notes of this series and of like tenor of a different authorized denomination, as requested in writing by the Holder surrendering the same. No service charge shall be made for any such registration of transfer or exchange, but the Issuer may require payment of a sum sufficient to cover any tax or other governmental charge payable in connection therewith. Prior to due presentment of this Note for registration of transfer and notice to the Trustee thereof the Issuer, the Trustee and any agent of the Issuer or the Trustee may treat the Person in

8 whose name this Note is registered as the owner hereof for all purposes, whether or not this Note be overdue, and neither the issuer, the Trustee nor any such agent shall be affected by notice to the contrary. The Issuer may deliver its signature page to this Note, and the Trustee may validly authenticate this Note, by manual, facsimile, or Electronic Signature, in each case which may be delivered by telecopier, facsimile or other electronic transmission (e.g. a “pdf” or “tif”), which shall be effective as delivery of a manually signature thereof and may be used in lieu of manual signature pages for all purposes. This Note shall not be valid until authenticated by the manual signature, facsimile, or Electronic Signature of the Trustee or an authenticating agent in accordance with the Indenture. An authenticating agent may authenticate Notes whenever the Trustee may do so. As used herein, “Electronic Signature” means any electronic signature covered by the Electronic Signatures in Global and National Commerce Act of 2000, Uniform Electronic Transactions Act, the Electronic Signatures and Records Act or other applicable law (e.g., www.docusign.com). Notwithstanding Section 2.5 of the Indenture, the Notes will not be required to be signed under the Issuer’s seal. THE INDENTURE AND THIS NOTE SHALL BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE COMMONWEALTH OF PENNSYLVANIA WITHOUT GIVING EFFECT TO PRINCIPLES OF CONFLICTS OF LAW. All terms used in this Note, which are not otherwise defined herein, but are defined in the Indenture shall have the meanings assigned to them in the Indenture.