| 1 | CPX | Capital Air Service, Inc. | Callsign: Capair, | USA | AVCODES |
| 2 | CPX | Cathay Pacific Airways Ltd. | IATA: CX, Callsign: Cathay, IATA Prefix: 160, ICAO designator changed to CPA | HK | AVCODES |
| 3 | CPX | Capital Air Service | | | ICAO1 |
| 4 | CPX | Central Packing Co., Inc. | 1/1950-10/1957; eliminated 4/1961 | | NAKINA |
| 5 | CPX | Central City Pickle Co. | 1/1945-4/1947 | | NAKINA |
| 6 | CPX | Cleveland Provision Co. | 7/1930 | | NAKINA |
| 7 | CPX | Cleveland Provision Car Co. | 8/1920-7/1923 | | NAKINA |
| 8 | CPX | Central Packing Co., Inc. | 1/52-10/57; eliminated 4/61 | | NRHS |
| 9 | CPX | *CLEVELAND PROVISION CO. | | | PWRC |
| 10 | CPX | *CENTRAL CITY PICKLE CO. | | | PWRC |
| 11 | CPX | *CENTRAL PACKING CO., INC. | | | PWRC |
| 12 | CPXC | COMPTON TRANSPORT LLC | | | SCAC4 |
| 13 | CPXD | CAPEX (A DIVISION OF 35061 ALBERTA | | | SCAC3 |
| 14 | CPXF | CTN EXPRESS TRANSPORT INC | | | SCAC4 |
| 15 | CPXG | C M C TRANSPORTATION LLC | | | SCAC4 |
| 16 | CPXI | CPX TRUCKING CO INC | | | SCAC3 |
| 17 | CPXI | CAPEX INDUSTRIES LIMITED | | | SCAC4 |
| 18 | CPXJ | CRESTLINE TRANSPORTATION INC | | | SCAC4 |
| 19 | CPXK | CAPE EXPRESS | | | SCAC3 |
| 20 | CPXK | COMPLETE TRANSPORTATION USA LTD | | | SCAC4 |
| 21 | CPXL | CIMPEX LTD | | | SCAC3 |
| 22 | CPXL | COPPER TRANSPORT LLC | | | SCAC4 |
| 23 | CPXM | C TRANSPORT PANAMAX B V | | | SCAC4 |
| 24 | CPXN | C P X INC | | | SCAC3 |
| 25 | CPXQ | COACH AMERICA PHOENIX | | | SCAC4 |
| 26 | CPXR | COOP TRANSPORT INC | | | SCAC4 |
| 27 | CPXT | CHAMPLAIN EXPRESS TRANSPORT (INTERN | | | SCAC3 |
| 28 | CPXU | COASTAL PACIFIC XPRESS INC | | | SCAC4 |
| 29 | CPXV | CRESPO TRANSPORT | | | SCAC4 |
| 30 | CPXW | CAPITAL EXPRESSWAYS INC | | | SCAC3 |
| 31 | CPXY | C P TRANSPORT INC | | | SCAC4 |
