Joinder Agreement, dated as of December 21, 2020, among TXU Energy Retail Company LLC, as seller party agent, Vistra Operations Company LLC, as guarantor, certain originators named therein, and MUFG Bank, Ltd., as buyer

Exhibit 10.1

JOINDER AGREEMENT

THIS JOINDER AGREEMENT dated as of December 21, 2020 is executed and delivered by each of the entities identified on the signature page hereto as a “Joining Originator” (each a “Joining Originator”, and collectively, the “Joining Originators”), in favor of MUFG Bank, Ltd., a Japanese banking corporation (“Buyer”), with respect to that certain Master Framework Agreement, dated as of October 9, 2020, by and among TXU Energy Retail Company LLC, a Texas limited liability company (“TXU”), as seller (the “Seller”), the various Originators from time to time party thereto, TXU, as seller party agent, and Buyer (as amended, restated, supplemented and otherwise modified from time to time, the “Framework Agreement”). Capitalized terms used and not otherwise defined are used with the meanings attributed thereto in the Framework Agreement (including those incorporated by reference therein), and the interpretive provisions of Section 1.2 of the Framework Agreement shall apply to this Joinder Agreement, mutatis mutandis.

Subject to receipt of counterparts hereof signed by the signatories below, by its signature below, each Joining Originator hereby absolutely and unconditionally agrees to become a party to the Framework Agreement as an Originator thereunder and to be bound by all of the provisions thereof, and hereby makes as to itself, as of the date hereof, each of the representations and warranties in Section 5.1 of the Framework Agreement, which representations and warranties shall, where applicable, be deemed to include this Joinder Agreement and the other agreements, documents, certificates and opinions delivered in connection herewith.

Attached hereto are (i) an amended and restated version of Schedule 3 to the Framework Agreement incorporating relevant information with respect to each Joining Originator, (ii) an amended and restated version of Schedule 4 to the Framework Agreement incorporating relevant information with respect to each Joining Originator and (iii) each of the other documents, certificates and opinions required to be delivered by each Joining Originator pursuant to Section 3.5 of the Framework Agreement. After giving effect to the amendments and restatements embodied in such Schedules 3 and 4 and the execution and delivery of this Joinder Agreement and the other aforementioned agreements, certificates, documents and opinions by each of the applicable parties hereto or thereto, each of the representations and warranties contained in Section 5.1 of the Framework Agreement will be true and correct in all material respects (except that any representation or warranty that is subject to any materiality qualification shall be true and correct in all respects) as to each Joining Originator.

The provisions of Article 9 of the Framework Agreement are incorporated in this Joinder Agreement by this reference with the same force and effect as if set forth in full herein except that references in such Article 9 to “this Framework Agreement” shall be deemed to refer to “this Joinder Agreement and to the Framework Agreement as modified by this Joinder Agreement.”

The Guarantor hereby acknowledges each Joining Originator’s entry into this Joinder Agreement and consents to the terms and conditions of this Joinder Agreement, it being understood that (i) such terms and conditions may affect the extent of the Obligations (as defined in the Guaranty) for which such Guarantor may be liable under the Guaranty and (ii) each Joining Originator shall constitute an “Originator” for purposes of the Guaranty. The Guarantor further confirms and agrees that the Guaranty remains in full force and effect after giving effect to this

Joinder Agreement and, for the avoidance of doubt, acknowledges that any amendment herein to a defined term in the Framework Agreement or the Master Repurchase Agreement (as the case may be) shall apply to terms in the Guaranty which are defined by reference to the Framework Agreement or Master Repurchase Agreement.

Please acknowledge your consent to each Joining Originator’s joinder to the Framework Agreement by signing the enclosed copy hereof in the appropriate space provided below.

[signature pages follow]

IN WITNESS WHEREOF, each Joining Originator has executed this Joinder Agreement as of the date first written above.

Each of the undersigned hereby consents to each Joining Originator’s joinder to the Framework Agreement:

SCHEDULE 3

UCC DETAILS SCHEDULE

Schedule 3-1

Schedule 3-2

Schedule 3-3

Schedule 3-4

Schedule 3-5

SCHEDULE 4

ORIGINATORS

Schedule 4