BOK FINANCIAL CORP

If you are the “record holder” of your shares (shares owned in your own name and not through a bank or brokerage firm), you may vote by phone, by mail, over the Internet, or in person (via live webcast) at the annual meeting. We encourage you to vote by phone, mail, or on the Internet in advance of the meeting even if you plan to attend the live webcast of the meeting.

If not revoked, your proxy will be voted at the annual meeting in accordance with your instructions marked on the proxy card. If you fail to mark your proxy with instructions, your proxy will be voted in accordance with the recommendations of the Board of Directors: (1)FOR the election of the fifteen (15) nominees for director listed in this Proxy Statement, (2)FOR the ratification of Ernst & Young LLP as the Company’s independent auditor for the fiscal year ending December 31, 2026, and (3)FOR the approval of the named executives’ compensation. If you are voting shares held in the BOKF Thrift Plan (also sometimes referred to as the BOKF 401(k) Plan) and you fail to mark your proxy with instructions, your shares will be voted by the Trustee of the Thrift Plan in the same ratio as those shares credited to the account of the Thrift Plan participants who do give instructions to the Trustee. George B. Kaiser currently owns approximately 62.50% of the outstanding common stock and plans to vote all of his shares FOR the three proposals.

If you hold your shares in “street name” (shares held in the name of a bank or broker on a person’s behalf), you must vote by following the instructions on the form that you receive from your broker or nominee. Without your instructions, your broker or nominee is permitted to use its own discretion and vote your shares on certain routine matters (such as Proposal 2), but is not permitted to use discretion and vote your shares on non-routine matters (such as Proposals 1 and 3). We urge you to give voting instructions to your broker on all voting proposals.

As to any other matter that may properly be brought before the annual meeting, your proxy will be voted as the Board of Directors may recommend. If the Board of Directors makes no recommendation, your proxy will be voted as the proxy holder named in your proxy card deems advisable. The Board of Directors does not know of any other matter that is expected to be presented for consideration at the annual meeting.

Any shareholder executing a proxy retains the right to revoke it any time prior to exercise at the annual meeting. A proxy may be revoked by (i) delivery of written notice of revocation to Tamara Sloan, Secretary, at 124 East Fourth Street, Tulsa, Oklahoma 74103, (ii) execution and delivery of a later proxy to the address indicated on the proxy card, or (iii) voting the shares electronically at the annual meeting. If not revoked, all shares represented by properly executed proxies will be voted as specified therein.