Exhibit 15.1
Consent of Independent Registered Public Accounting Firm
The Board of Directors
Greenbrook TMS Inc.:
We consent to the use of our report dated March 31, 2022, on the consolidated financial statements of Greenbrook TMS Inc. (the “Entity”) which comprise the consolidated statements of financial position as of December 31, 2021 and December 31, 2020, the related consolidated statements of net loss and comprehensive loss, changes in equity and cash flows for each of the years in the three-year period ended December 31, 2021, and the related notes (collectively the “consolidated financial statements”), which is included in the Annual Report on Form 20-F of the Entity for the fiscal year ended December 31, 2021.
We also consent to the incorporation by reference of such report in the Registration Statements (No. 333-254880 and 333-257680) on Form S-8 of the Entity.
/s/ KPMG LLP
Chartered Professional Accountants, Licensed Public Accountants
March 31, 2022
Vaughan, Canada
KPMG LLP, an Ontario limited liability partnership and member firm of the KPMG global organization of independent
member firms affiliated with KPMG International Limited, a private English company limited by guarantee.
KPMG Canada provides services to KPMG LLP.