Exhibit 32

CERTIFICATION

I, David Harlow, Chief Executive Officer and Kevin Lawrence, Chief Financial Officer of BancFirst Corporation (the “Company”), certify, pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, 18 U.S.C. Section 1350, that:

(1) The Annual Report on Form 10-K of the Company for the annual period ended December 31, 2018 (the “Report”) fully complies with the requirements of section 13(a) of the Securities Exchange Act of 1934 (15 U.S.C. 78m); and

(2) The information contained in the Form 10-K fairly presents, in all material respects, the financial condition and results of operations of the Company.

/s/ David Harlow 

David Harlow

President and Chief Executive Officer

(Principal Executive Officer)

February 26, 2019

/s/ Kevin Lawrence 

Kevin Lawrence

Executive Vice President

and Chief Executive Officer

(Principal Financial Officer)

February 26, 2019