OPPENHEIMER HOLDINGS INC. 85 Broad Street New York, NY 10004

NOTICE OF ANNUAL MEETING OF STOCKHOLDERS TO BE HELD ON MAY 10, 2021 To our Stockholders: NOTICE IS HEREBY GIVEN that the Annual Meeting of Stockholders of OPPENHEIMER HOLDINGS INC., a Delaware corporation (the ‘‘Company’’), will be held virtually on Monday, May 10, 2021, at the hour of 4:30 P.M. (New York time) for the following purposes: 1. To elect nine directors; 2. To ratify the appointment of Deloitte & Touche LLP as auditors of the Company for 2021 and authorize the Audit Committee to fix the auditors’ remuneration; and 3. To transact such other business as is proper at such meeting or any adjournments thereof. Only holders of Class B voting common stock of record at the close of business on March 15, 2021 will be entitled to vote at the Annual Meeting of Stockholders and any adjournments thereof. Holders of Class B voting common stock who are unable to attend the meeting virtually are requested to date, sign and return the enclosed form of proxy for use by holders of Class B voting common stock. Detailed instructions to remotely access, participate in and vote at the virtual Annual Meeting of Stockholders are available at www.oppenheimer.com/about-us/investor-relations/proxies.aspx. Holders of Class A non-voting common stock of the Company are entitled to listen in and to view the Annual Meeting of Stockholders and any adjournments thereof, and will have an opportunity to submit questions for consideration and response at or after the meeting by emailing [email protected]. Holders of Class A non-voting common stock are not entitled to vote with respect to the matters referred to above. A copy of the Company’s Annual Report on Form 10-K for the year ended December 31, 2020 is available on the Company’s website at www.oppenheimer.com. Paper copies are available, free of charge, upon request, by (i) writing to Oppenheimer Holdings Inc., 85 Broad Street, 22nd Floor, New York, New York 10004, Attention: Secretary, (ii) calling 1-800-221-5588, (iii) emailing us with your request at [email protected], or (iv) through our website at www.oppenheimer.com/investor-relations/index.aspx.

By Order of the Board of Directors,

17MAR202010172614 Dennis P. McNamara Secretary

New York, New York March 19, 2021

Important Notice Regarding the Internet Availability of Proxy Materials for the Annual Meeting of Stockholders to be held on May 10th, 2021: The Notice of Meeting, Proxy Statement and Annual Report to Stockholders are available at https://www.oppenheimer.com/investor-relations/index.aspx. OPPENHEIMER HOLDINGS INC.

PROXY STATEMENT SUMMARY This summary highlights selected information appearing elsewhere in this proxy statement and does not contain all the information that you should consider in making a decision with respect to the proposals described in this proxy statement. You should read this summary in its entirety, together with the more detailed information in this proxy statement, as well as our Annual Report on Form l0-K for the year ended December 31, 2020, which is available without charge, except for exhibits to the report, by (i) writing to Oppenheimer Holdings Inc., 85 Broad Street, 22nd Floor, New York, New York 10004, Attention: Secretary, (ii) calling 1-800-221-5588, (iii) emailing us with your request at [email protected] or (iv) through our website at www.oppenheimer.com/investor-relations/index.aspx. Unless otherwise provided in this proxy statement, references to the ‘‘Company,’’ ‘‘Oppenheimer Holdings,’’ ‘‘we,’’ ‘‘us,’’ and ‘‘our’’ refer to Oppenheimer Holdings Inc., a Delaware corporation.

Oppenheimer Holdings Inc. The Company is a holding company which, through its subsidiaries, is a leading middle-market investment and full service firm. Through our operating subsidiaries, we provide a broad range of financial services, including retail securities brok