Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON D.C. 20549 FORM 10-Q (Mark One) ☒ Quarterly report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934. For the quarterly period ended March 31, 2024 ☐ Transition report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934. For the transition period from to Commission File Number 001-40199 GREENBROOK TMS INC. (Exact name of Registrant as Specified in its Charter) Ontario 98-1512724 (State or ot ...

Exhibit 99.1 -2- SELECTED FIRST QUARTER FINANCIAL AND OPERATING RESULTS Selected Financial Results | (unaudited) ($) | Q1 2024 | Q1 2023 | | --- | --- | --- | | Total revenue | 18,012,190 | 19,304,461 | | Regional operating loss | (2,491,800) | (497,505) | | Loss before income taxes | (14,540,145) | (10,660,136) | | Loss for the year and comprehensive loss | (14,540,145) | (10,660,136) | | Loss attributable to the common shareholders of | | | | Greenbrook | (14,218,296) | (10,591,310) | | Net loss per share ...

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K (Mark one) ☒ ANNUAL REPORT UNDER SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2023. ☐ TRANSITION REPORT UNDER SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Commission file number: 001-40199 GREENBROOK TMS INC. (Exact name of registrant as specified in its charter) Ontario 98-1512724 (State or other jurisdiction of incorporation or organization) ...

Company Participants Erns Loubser - Chief Financial Officer David Martin - Bloom Burton Operator Factors that could cause actual results or events to differ materially from current expectations are discussed in the Risk Factors section of the company's annual report on Form 20-F for the fiscal year ended December 31, 2022, and in the company's other materials filed with the Canadian securities regulatory authorities and the U.S. Securities and Exchange Commission from time to time, which are available on SE ...

Financial Data and Key Metrics Changes - Quarterly revenue increased by 52% to $19.9 million, up $6.8 million compared to Q1 2022, primarily due to the acquisition of Success TMS and strong performance in mature regions [9][28] - Adjusted EBITDA loss reduced by 45% compared to Q4 2022, indicating progress towards near-term profitability [5] - The loss for the period increased by 16% to $9.3 million during Q1 2023, mainly due to increased interest expenses and depreciation from the Success TMS acquisition [33] Business Line Data and Key Metrics Changes - Patient starts and treatment volumes both increased by 57% to 2,854 and 92,533, respectively, compared to Q1 2022 [9][35] - Average revenue per treatment decreased by 3% to $215 in Q1 2023, attributed to changes in payer mix and geographical revenue distribution [31] Market Data and Key Metrics Changes - Same region sales growth was 26.8% in Q1 2023 compared to 8.3% in Q1 2022, driven by strong performance in mature regions [10] - The company expanded its Spravato offering to 45 treatment centers, addressing the high unmet demand for mental health treatment in the U.S. [7][30] Company Strategy and Development Direction - The company is focused on executing a comprehensive restructuring plan aimed at reducing costs and streamlining operations, with a target of $22 million to $25 million in cost reductions [6][15] - The restructuring plan has already led to a return to positive regional operating income, positioning the company for future profitability [15][32] Management's Comments on Operating Environment and Future Outlook - Management noted positive momentum in payer criteria for TMS and the use of non-physician practitioners, which is a favorable sign for the industry [29] - The company believes it is on track to achieve operational synergies through the restructuring plan, enhancing regional operating income [32] Other Important Information - The total number of treatment centers increased by 9% to 162 from 148 a year ago, but the operating footprint has been reduced to 133 treatment centers as part of the restructuring [13][30] - The company has treated over 32,000 patients with more than 1.2 million treatments performed, indicating a significant positive impact on mental health [38] Q&A Session Summary Question: Can you provide details on the Neuronetics partnership and its expected benefits? - The partnership with Neuronetics is strong, focusing on increasing the ability to treat more patients and enhance the industry [40] Question: What are the expected levels for corporate G&A and regional center support costs post-restructuring? - Corporate G&A is currently about $6 million, with a target to reduce it to between $4 million and $4.5 million by 2024 [45] Question: Can you discuss the liquidity position and the ability to proceed through restructuring? - The company is in discussions to shore up its balance sheet and has interest in additional capital, supported by a lender [51] Question: What is the current status of accounts receivable and any associated risks? - Accounts receivable increased slightly, but management does not see significant risk, expecting a reversion in collections [52] Question: How has the Spravato offering performed in terms of revenue contribution? - Spravato accounted for over 10% of total revenue, with expectations for continued growth throughout the year [56]

Company Participants David Martin - Bloom Burton This call contains forward-looking statements, which reflect the current expectations or beliefs of the company based on current -- currently available information. Forward-looking statements are subject to a number of risks and uncertainties that may cause the actual results of the company to differ materially from those discussed in the forward-looking statements. And now I would like to turn the meeting over to Mr. Bill Leonard, President and Chief Executi ...

Exhibit 99.1 GREENBROOK TMS REPORTS FISCAL 2022 OPERATIONAL AND FINANCIAL RESULTS April 17, 2023 – Toronto, Ontario – Greenbrook TMS Inc. (NASDAQ: GBNH) ("Greenbrook" or the "Company"), today announced its fourth quarter 2022 ("Q4 2022") and year-end 2022 ("Fiscal 2022") operational and financial results. All values in this news release are in United States dollars, unless otherwise stated. FISCAL 2022 OPERATIONAL AND FINANCIAL HIGHLIGHTS FOURTH QUARTER 2022 OPERATIONAL AND FINANCIAL HIGHLIGHTS RESTRUCTURIN ...

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 20-F ☐ REGISTRATION STATEMENT PURSUANT TO SECTION 12(b) OR 12(g) OF THE SECURITIES EXCHANGE ACT OF 1934 OR ☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2022 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to OR ☐ SHELL COMPANY REPORT PURSUANT TO SECTION 13 OR ...

Exhibit 99.1 GREENBROOK TMS INC. Form 51-102F4 Business Acquisition Report Item 1 – Identity of Company Item 2 – Details of Acquisition 2.1 Nature of Business Acquired 1.1 Name and Address of Company Greenbrook TMS Inc. (the "Company") 890 Yonge Street, 7 Floor Toronto, ON M4W 3P4 1.2 Executive Officer For further information, please contact: Erns Loubser Chief Financial Officer (416) 322-9700 x548 On July 14, 2022, the Company, through its wholly-owned U.S. subsidiary, TMS NeuroHealth Centers Inc., complet ...

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 20-F ☐ REGISTRATION STATEMENT PURSUANT TO SECTION 12(b) OR 12(g) OF THE SECURITIES EXCHANGE ACT OF 1934 OR ☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2021 OR ☐ SHELL COMPANY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of event requiring this shell company report For the transition period from _ ...