ICOCA can be used at the following 281 stations of JR West Kinki district, 135 stations of JR West Chugoku district, the stations of the entities where PiTaPa has been introduced, the five companies in which Suica has been introduced (Tokyo Metropolitan Area, Sendai Area and Niigata Area of JR East; Tokyo Monorail Co., Ltd.; Tokyo Waterfront Area Rapid Transit, Inc.; Saitama New Urban Transit Co., Ltd.; Sendai Airport Transit Co., Ltd.), and the stations in the TOICA area of JR Central.
ICOCAは、下記のJR西日本の近畿地区281駅・中国地区135駅の他、PiTaPaを導入している事業者やSuica導入5社の利用可能駅（首都圏・仙台・新潟地区の東日本旅客鉄道・東京モノレール・東京臨海高速鉄道・埼玉新都市交通・仙台空港鉄道）、JR東海のTOICAエリアでも利用できる。