Exhibit 21 WESTERN RESOURCES, INC. Subsidiaries of the Registrant State of Date Subsidiary Incorporation Incorporated 1) Kansas Gas and Electric Company Kansas October 9, 1990 2) Mid Continent Market Center, Inc. Kansas December 13, 1994 3) Westar Business Services Kansas April 14, 1995 4) Westar Consumer Services Kansas April 14, 1995 5) Westar Capital Kansas October 8, 1990