| 1 | PCX | Pacific Aviation Corporation | | USA | AVCODES |
| 2 | PCX | Pacific Aviation (United States) | | | ICAO1 |
| 3 | PCX | Packers Car Line Co. | added 4/1957; 10/1957-4/1970; eliminated 7/1972 | | NAKINA |
| 4 | PCX | Pittsburgh Coal Carbonization Co. | 7/1935-1/1946 | | NAKINA |
| 5 | PCX | Pelican Oil Refining Co., Inc. | 8/1920 | | NAKINA |
| 6 | PCX | Pittsburgh Coal Carbonization Co. | Apr-38 | | NRHS |
| 7 | PCX | Packers Car Line Co. | added 4/57; 10/57-4/70 | | NRHS |
| 8 | PCX | *PELICAN OIL REFINING CO., INC. | | | PWRC |
| 9 | PCX | *PITTSBURGH COAL CARBONIZATION CO. | | | PWRC |
| 10 | PCX | *PACKERS CAR LINE CO. | | | PWRC |
| 11 | PCXC | PACIFIC SEAS TRANSPORT INC | | | SCAC4 |
| 12 | PCXE | PACIFIC XPRESS TRUCKING INC | | | SCAC4 |
| 13 | PCXG | P & C TRANSPORTS LLC | | | SCAC4 |
| 14 | PCXI | PACIFIC EXPRESS INC | | | SCAC3 |
| 15 | PCXL | PACIFIC COAST EXPRESS LIMITED | | | SCAC4 |
| 16 | PCXN | PC EXPRESS INC | | | SCAC4 |
| 17 | PCXR | PACIFIC COAST EXPRESS | | | SCAC4 |
| 18 | PCXS | PROCON EXPRESS LINES | | | SCAC4 |
| 19 | PCXU | SHIRLSTAR CONTAINER TRANSPORT | | | SCAC4 |
| 20 | PCXW | PROTECH EXPRESS TOWING | | | SCAC4 |
