OPPENHEIMER HOLDINGS INC

REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

To the Stockholders and the Board of Directors of Oppenheimer Holdings Inc.

Opinion on the Financial Statements

We have audited the accompanying consolidated balance sheets of Oppenheimer Holdings Inc. and subsidiaries (the “Company”) as of December 31, 2023 and 2022, the related consolidated income statements, statements of comprehensive income, statements of changes in stockholders’ equity and redeemable noncontrolling interests, and statements of cash flows, for each of the three years in the period ended December 31, 2023, and the related notes (collectively referred to as the “financial statements”). In our opinion, the financial statements present fairly, in all material respects, the financial position of the Company as of December 31, 2023 and 2022, and the results of its operations and its cash flows for each of the three years in the period ended December 31, 2023, in conformity with accounting principles generally accepted in the United States of America.

We have also audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States) (PCAOB), the Company’s internal control over financial reporting as of December 31, 2023, based on criteria established in Internal Control — Integrated Framework (2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission and our report dated March 1, 2024, expressed an unqualified opinion on the Company’s internal control over financial reporting.

Basis for Opinion

These financial statements are the responsibility of the Company’s management. Our responsibility is to express an opinion on the Company’s financial statements based on our audits. We are a public accounting firm registered with the PCAOB and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audits in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement, whether due to error or fraud. Our audits included performing procedures to assess the risks of material misstatement of the financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the financial statements. We believe that our audits provide a reasonable basis for our opinion.

Critical Audit Matter

The critical audit matter communicated below is a matter arising from the current-period audit of the financial statements that was communicated or required to be communicated to the audit committee and that (1) relates to accounts or disclosures that are material to the financial statements and (2) involved our especially challenging, subjective, or complex judgments. The communication of critical audit matter does not alter in any way our opinion on the financial statements, taken as a whole, and we are not, by communicating the critical audit matter below, providing a separate opinion on the critical audit matter or on the accounts or disclosures to which it relates.

Advisory Fees – Earned on Asset-based programs - Refer to Note 6 to the financial statements

Critical Audit Matter Description

The Company earns advisory fees in connection with advisory and asset management services it provides to various types of funds and investment vehicles through its subsidiaries. Advisory fees earned on asset-based programs are generally based on the customer’s account value at the valuation date per the respective asset management agreements. Fees are calculated based on underlying information, such as asset balances and rates, sourced from multiple internal and external systems. Advisory fees earned on assets held in the Company’s asset-based programs are included as a part of the Company’s total advisory fee revenue.

Given the Company's use of multiple systems and databases in recording advisory fees earned on asset-based programs, auditing advisory fees earned on asset-based programs was complex and challenging due to the extent of audit effort required to evaluate the completeness and accuracy of underlying information and required the involvement of information technology (IT) professionals with specialized skills and expertise.

How the Critical Audit Matter Was Addressed in the Audit

Our audit procedures related to the Company’s systems to process advisory fees earned on asset-based programs included the following, among others:

•With the assistance of our IT specialists, we identified the significant systems used in the calculation of advisory fees earned on asset-based programs and, using a risk-based approach, tested the relevant general IT controls over each of these systems. Additionally, for the relevant service organizations, we obtained the service auditor's reports and evaluated IT-related controls, related exceptions and complementary user entity controls specified in the reports.

•We tested the effectiveness of controls over the Company’s advisory fees earned on asset-based programs, including automated business controls and system interface controls, as well as the controls designed to ensure the accuracy and completeness of advisory fees earned on asset-based programs.

•With the assistance of our data specialists, we created data visualizations to evaluate recorded advisory fees earned on asset-based programs and evaluate trends in the transactional revenue data.

•For a sample of advisory fees earned on asset-based programs, we performed detail testing by agreeing the amounts recognized to source documents and testing the mathematical accuracy of the recorded advisory fees earned on asset-based programs.

•For a sample of accounts within the asset-based programs, we tested the accuracy and completeness of assets under management by obtaining independent pricing support and reconciling total positions to third-party statements.

/s/ Deloitte & Touche LLP

New York, New York

March 1, 2024

We have served as the Company's auditor since 2013.