Exhibit 21

BOK FINANCIAL CORPORATION

SUBSIDIARIES OF THE REGISTRANT

Banking Subsidiaries

BOKF, National Association (1)

Other subsidiaries of BOK Financial Corporation

BOKF Capital Corporation

BOKF-CC (Collision Works), LLC

BOKFCC (Cyber), LLC

BOKFCC (FDS), LLC

BOKFCC (Fixed Income II), LLC

BOKF-CC (FSE), LLC

BOKF-CC (HD Repair), LLC

BOKF-CC (IPS), LLC

BOKF-CC (O2 Concepts), LLC

BOKF-CC (QRC), LLC

BOKF-CC (SSP), LLC

BOKF-CC (Switchgrass), LLC

BOKF-CC (VFP), LLC

BOKFCC Merchant Banking Fund I, LLC

BOKFCC MB II, LLC

BOKFCC MB III, LLC

BOKF Energy Fund Investment I, LLC

BOK Financial Private Wealth, Inc. (5)

BOK Financial Securities, Inc.

Cavanal Hill Distributors, Inc.

Industrial Pipe & Supply, LLC

Lumifi Holdco, LLC

RMA Holdings, Inc. (5)

Switchgrass I, LLC

Switchgrass II, LLC

Switchgrass III, LLC

Switchgrass IV, LLC

Switchgrass V, LLC

Switchgrass VI, LLC

Switchgrass Holdings, LLC

Switchgrass Management, LLC

Switchgrass Properties, LLC

Switchgrass Properties-II, LLC

Subsidiaries of BOKF, National Association (1)

Affiliated BancServices, Inc.

Affiliated Financial Holding Co.

Affiliated Financial Insurance Agency, Inc.

BancOklahoma Agri-Service Corporation

BOK Delaware, Inc. (3)

BOK Financial Equipment Finance, Inc.

BOK Financial Public Finance, Inc. (5)

BOK Funding Trust (3)

BOKF Community Development Fund, LLC

BOKF Community Development Fund II

BOKF Community Development Corporation

BOKF Investment Fund II, LLC

BOKF Petro Holding, LLC

BOKF Petro Holdings II, LLC

BOKF Petro Holdings III, LLC

BOKF Petro Holdings IV, LLC

BOSC Agency, Inc. (Oklahoma)

BOSC Agency, Inc. (New Mexico) (4)

BOSC Agency, Inc. (Texas) (2)

Cavanal Hill Investment Management, Inc.

Cottonwood Valley Ventures, Inc.

CVV Management, Inc.

CVV Partnership, an Oklahoma General Partnership

All Subsidiaries listed above were incorporated in Oklahoma, except as noted.

(1)Chartered by the United States Government

(2)Incorporated in Texas

(3)Incorporated in Delaware

(4)Incorporated in New Mexico

(5)Incorporated in Colorado