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vistra-20260507

FALSE0001692819CHX00016928192026-05-072026-05-070001692819exch:XCHI2026-05-072026-05-07

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, DC 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d)

of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): May 7, 2026

VISTRA CORP.

(Exact name of registrant as specified in its charter)

Delaware 001-3808636-4833255

(State or other jurisdiction of incorporation or organization) (Commission File Number) (I.R.S. Employer Identification No.)

6555 Sierra Drive,

Irving,

Texas 75039(214)812-4600

(Address of principal executive offices) (Zip Code) (Registrant's telephone number, including area code)

N/A

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

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

☐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.l4a-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

Common stock, par value $0.01 per shareVSTNew York Stock Exchange

NYSE Texas

Indicate by check mark whether the registrant is an emerging growth company 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 the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item 2.02.Results of Operations and Financial Condition.

On May 7, 2026, Vistra Corp. (the “Company”) issued a news release announcing, among other matters, its financial results for the quarter ended March 31, 2026. A copy of such news release is furnished herewith as Exhibit 99.1 to this Current Report on Form 8-K. In accordance with General Instruction B.2 of Form 8-K, the information set forth in this Item 2.02 and in the attached Exhibit 99.1 is deemed to be furnished and shall not be deemed to be “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”).

Item 9.01.Financial Statements and Exhibits.

(d)    Exhibits.

Exhibit No.Description

99.1 News release dated May 7, 2026

104The cover page from this Current Report on Form 8-K, formatted in Inline XBRL

SIGNATURES

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

Vistra Corp.

Dated: May 7, 2026/s/ Margaret Montemayor

Name:Margaret Montemayor

Title:Senior Vice President and Chief Accounting Officer

8-K

false 0001692819 0001692819 2026-02-26 2026-02-26

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, DC 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): February 26, 2026

VISTRA CORP.

(Exact name of registrant as specified in its charter)

Delaware

001-38086

36-4833255

(State or other jurisdiction of incorporation or organization)

(Commission File Number)

(I.R.S. Employer Identification No.)

6555 Sierra Drive Irving, TX

75039

(Address of principal executive offices)

(Zip Code) (214) 812-4600 (Registrant’s telephone number, including area code) N/A (Former name or former address, if changed since last report)

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

☐ 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.l4a-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 Class

Trading Symbol(s)

Name of Each Exchange on Which Registered

Common stock, par value $0.01 per share

VST

New York Stock Exchange

Indicate by check mark

NYSE Texas Indicate by check mark whether the registrant is an emerging growth company 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 the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item 2.02. Results of Operations and Financial Condition.

On February 26, 2026, Vistra Corp. (the “Company”) issued a news release announcing, among other matters, its financial results for the quarter and year ended December 31, 2025. A copy of such news release is furnished herewith as Exhibit 99.1 to this Current Report on Form 8-K. In accordance with General Instruction B.2 of Form 8-K, the information set forth in this Item 2.02 and in the attached Exhibit 99.1 is deemed to be furnished and shall not be deemed to be “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”).

Item 9.01. Financial Statements and Exhibits.

(d) Exhibits.

Exhibit No.

Description

99.1

News release dated February 26, 2026

104

The cover page from this Current Report on Form 8-K, formatted in Inline XBRL

SIGNATURES

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

Vistra Corp.

Dated: February 26, 2026

/s/ Margaret Montemayor

Name:

Margaret Montemayor

Title:

Senior Vice President and Chief Accounting Officer