CEG

ceg-20260224Pennsylvania1310 Point StreetBaltimoreMaryland21231-3380(833)883-0162Pennsylvania200 Energy WayKennett SquarePennsylvania19348-2473(833)883-016200018682750001168165False00018682752026-02-242026-02-240001868275ceg:ConstellationEnergyGenerationLLCMember2026-02-242026-02-24

UNITED STATES SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 February 24, 2026 Date of Report (Date of earliest event reported)

Commission File NumberName of Registrant; State or Other Jurisdiction of Incorporation; Address of Principal Executive Offices; and Telephone NumberIRS Employer Identification Number

001-41137CONSTELLATION ENERGY CORPORATION87-1210716

(a Pennsylvania corporation) 1310 Point Street Baltimore, Maryland 21231-3380 (833) 883-0162

333-85496CONSTELLATION ENERGY GENERATION, LLC23-3064219

(a Pennsylvania limited liability company) 200 Energy Way Kennett Square, Pennsylvania 19348-2473 (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: ☐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: Title of each classTrading Symbol(s)Name of each exchange on which registered

CONSTELLATION ENERGY CORPORATION:

Common Stock, without par valueCEG 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. ☐

Section 2 - Financial Information Item 2.02. Results of Operations and Financial Condition Section 7 - Regulation FD Item 7.01. Regulation FD Disclosure

On February 24, 2026, Constellation Energy Corporation (Nasdaq: CEG) announced via press release its results for the fourth quarter ended December 31, 2025. A copy of the press release and related attachments are attached hereto as Exhibit 99.1.

This Form 8-K and the attached exhibits are provided under Items 2.02, 7.01 and 9.01 of Form 8-K and are furnished to, but not filed with, the Securities and Exchange Commission.

Section 9 - Financial Statements and Exhibits Item 9.01. Financial Statements and Exhibits

(d)    Exhibits.

Exhibit No.Description 99.1 Press release and earnings release attachments

101Cover Page Interactive Data File - the cover page XBRL tags are embedded within the Inline XBRL document. 104The cover page from the 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 the Registrant on its own behalf. Neither Registrant makes any representation as to information relating to the other Registrant.

This report 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 our 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 acquisition of Calpine Corporation, the pro forma combined company and its operations, strategies and plans, enhancements to investment-grade credit profile, synergies, opportunities and anticipated future performance and capital structure, and expected accretion to earnings per share and free cash flow. Information adjusted for the acquisition should not be considered a forecast of future results.

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. The factor

ceg-20251107Pennsylvania1310 Point StreetBaltimoreMaryland21231-3380(833)883-0162Pennsylvania200 Energy WayKennett SquarePennsylvania19348-2473(833)883-0162Common Stock, without par valueCEGThe Nasdaq Stock Market LLC00018682750001168165False☐00018682752025-11-072025-11-070001868275ceg:ConstellationEnergyGenerationLLCMember2025-11-072025-11-07

UNITED STATES SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 November 7, 2025 Date of Report (Date of earliest event reported)

Commission File NumberName of Registrant; State or Other Jurisdiction of Incorporation; Address of Principal Executive Offices; and Telephone NumberIRS Employer Identification Number

001-41137CONSTELLATION ENERGY CORPORATION87-1210716

(a Pennsylvania corporation) 1310 Point Street Baltimore, Maryland 21231-3380 (833) 883-0162

333-85496CONSTELLATION ENERGY GENERATION, LLC23-3064219

(a Pennsylvania limited liability company) 200 Energy Way Kennett Square, Pennsylvania 19348-2473 (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: ☐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: Title of each classTrading Symbol(s)Name of each exchange on which registered

CONSTELLATION ENERGY CORPORATION:

Common Stock, without par valueCEG 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. ☐

Section 2 - Financial Information Item 2.02. Results of Operations and Financial Condition Section 7 - Regulation FD Item 7.01. Regulation FD Disclosure On November 7, 2025, Constellation Energy Corporation (Nasdaq: CEG) announced via press release its results for the third quarter ended September 30, 2025. A copy of the press release and related attachments are attached hereto as Exhibit 99.1. Also attached as Exhibit 99.2 to this Current Report on Form 8-K are the presentation slides to be used during the third quarter 2025 earnings conference call. This Form 8-K and the attached exhibits are provided under Items 2.02, 7.01 and 9.01 of Form 8-K and are furnished to, but not filed with, the Securities and Exchange Commission. We have scheduled the conference call for 10:00 AM ET on November 7, 2025. To access the call by phone, please follow the registration link available on the Investor Relations page of our website: https://investors.constellationenergy.com. The call will also be webcast and archived on the Investor Relations page of our website. Media representatives are invited to participate on a listen-only basis. Section 9 - Financial Statements and Exhibits Item 9.01. Financial Statements and Exhibits

(d)    Exhibits.

Exhibit No.Description 99.1 Press release and earnings release attachments

99.2 Earnings conference call presentation slides

101Cover Page Interactive Data File - the cover page XBRL tags are embedded within the Inline XBRL document. 104The cover page from the 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 the Registrant on its own behalf. Neither Registrant makes any representation as to information relating to the other Registrant. This report 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 our 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

ceg-20250807Pennsylvania1310 Point StreetBaltimoreMaryland21231-3380(833)883-0162Pennsylvania200 Energy WayKennett SquarePennsylvania19348-2473(833)883-0162Common Stock, without par valueCEGThe Nasdaq Stock Market LLC00018682750001168165False☐00018682752025-08-072025-08-070001868275ceg:ConstellationEnergyGenerationLLCMember2025-08-072025-08-07

UNITED STATES SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 August 7, 2025 Date of Report (Date of earliest event reported)

Commission File NumberName of Registrant; State or Other Jurisdiction of Incorporation; Address of Principal Executive Offices; and Telephone NumberIRS Employer Identification Number

001-41137CONSTELLATION ENERGY CORPORATION87-1210716

(a Pennsylvania corporation) 1310 Point Street Baltimore, Maryland 21231-3380 (833) 883-0162

333-85496CONSTELLATION ENERGY GENERATION, LLC23-3064219

(a Pennsylvania limited liability company) 200 Energy Way Kennett Square, Pennsylvania 19348-2473 (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: ☐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: Title of each classTrading Symbol(s)Name of each exchange on which registered

CONSTELLATION ENERGY CORPORATION:

Common Stock, without par valueCEG 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. ☐

Section 2 - Financial Information Item 2.02. Results of Operations and Financial Condition Section 7 - Regulation FD Item 7.01. Regulation FD Disclosure On August 7, 2025, Constellation Energy Corporation (Nasdaq: CEG) announced via press release its results for the second quarter ended June 30, 2025. A copy of the press release and related attachments are attached hereto as Exhibit 99.1. Also attached as Exhibit 99.2 to this Current Report on Form 8-K are the presentation slides to be used during the second quarter 2025 earnings conference call. This Form 8-K and the attached exhibits are provided under Items 2.02, 7.01 and 9.01 of Form 8-K and are furnished to, but not filed with, the Securities and Exchange Commission. We have scheduled the conference call for 10:00 AM ET on August 7, 2025. To access the call by phone, please follow the registration link available on the Investor Relations page of our website: https://investors.constellationenergy.com. The call will also be webcast and archived on the Investor Relations page of our website. Media representatives are invited to participate on a listen-only basis. Section 9 - Financial Statements and Exhibits Item 9.01. Financial Statements and Exhibits

(d)    Exhibits.

Exhibit No.Description 99.1 Press release and earnings release attachments

99.2 Earnings conference call presentation slides

101Cover Page Interactive Data File - the cover page XBRL tags are embedded within the Inline XBRL document. 104The cover page from the 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 the Registrant on its own behalf. Neither Registrant makes any representation as to information relating to the other Registrant. This report 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 our 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