BOK Financial (BOKF) 10-K 2017 FY Annual report

Exhibit 32

CERTIFICATION PURSUANT TO

18 U.S.C. SECTION 1350,

AS ADOPTED PURSUANT TO

SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

In connection with the Annual Report of BOK Financial Corporation (“BOK Financial”) on Form 10-K for the fiscal year ending December 31, 2017 as filed with the Securities and Exchange Commission on the date hereof (the “Report”), we, Steven G. Bradshaw and Steven E. Nell, Chief Executive Officer and Chief Financial Officer, respectively, of BOK Financial, certify, pursuant to 18 U.S.C. § 1350, as adopted pursuant to § 906 of the Sarbanes-Oxley Act of 2002, that to our knowledge:

1. The Report fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934; and

2. The information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of BOK Financial as of, and for, the periods presented.

February 27, 2018

/s/ Steven G. Bradshaw       

Steven G. Bradshaw

President

Chief Executive Officer

BOK Financial Corporation

/s/ Steven E. Nell            

Steven E. Nell

Executive Vice President

Chief Financial Officer

BOK Financial Corporation