| 1 | PRX | VIP Avia | Callsign: Parex, Name changed from Vip Aviation | LV | AVCODES |
| 2 | PRX | VIP Aviation | Callsign: Parex, Name changed to Vip Avia | LV | AVCODES |
| 3 | PRX | Pradhaan Air Express Private Ltd | IATA: 6P, Callsign: Pradhaan, IATA Prefix: 339, JV between Astral Aviation (Kenya) and UAE-based lessor Vaayu Group. Planned start up with A320-200(P2F). | IND | AVCODES |
| 4 | PRX | VIP Avia | | | ICAO1 |
| 5 | PRX | Palomar Oil & Refining Corp. | 4/1947-4/1961; eliminated 1/1964 | | NAKINA |
| 6 | PRX | Palomar Refining Co. | 1/1943-1/1946 | | NAKINA |
| 7 | PRX | Pennsylvania-Conley Tank Line, a Division of General American Transportation Corp. | 7/1937 (not listed) | | NAKINA |
| 8 | PRX | Pennsylvania Refining Co. | 7/1923-7/1935 | | NAKINA |
| 9 | PRX | The Pennsylvania Refining Co., Ltd. | 8/1920 | | NAKINA |
| 10 | PRX | Palomar Oil & Refining Corp. | 1/52-4/61 | | NRHS |
| 11 | PRX | PALOMAR OIL & REFINING CORP. [PENNSYLVANIA-CONLEY TANK LINE, DIV. GATX; PENNSYLVANIA REFINING CO.} | | | PWRC |
| 12 | PRXA | POLAR SOLUTIONS INC | | | SCAC4 |
| 13 | PRXB | PLANET ROAMER EXPRESS INC | | | SCAC4 |
| 14 | PRXD | PROFESSIONAL EXPEDITING INC | | | SCAC4 |
| 15 | PRXF | PUERTO RICO EXPRESS FREIGHT INC | | | SCAC3 |
| 16 | PRXG | PUERTO RICO INTERNATIONAL CARGO EXP | | | SCAC4 |
| 17 | PRXH | PREX | | | SCAC3 |
| 18 | PRXH | PIEDMONT REGIONAL TRANSPORT INC | | | SCAC4 |
| 19 | PRXI | P R EXPRESS COURIER INC | | | SCAC3 |
| 20 | PRXI | PRAXAIR INC | | | SCAC4 |
| 21 | PRXJ | PILLAR TRANS CALIFORNIA | | | SCAC4 |
| 22 | PRXL | PATRICK REFRIGERATED EXPRESS LTD | | | SCAC3 |
| 23 | PRXN | PRICE, T H REFRIGERATED EXPRESS INC | | | SCAC3 |
| 24 | PRXO | PROULX OIL SERVICE INC | | | SCAC4 |
| 25 | PRXP | PRESS EXPRESS | | | SCAC3 |
| 26 | PRXP | PRIORITY XPRESS INC | | | SCAC4 |
| 27 | PRXQ | PARTS EXPRESS INC | | | SCAC3 |
| 28 | PRXR | PRIORITY COURIER INC | | | SCAC4 |
| 29 | PRXS | PRESIDENTIAL EXPRESS TRUCKING | | | SCAC3 |
| 30 | PRXS | PRESIDENTIAL EXPRESS TRUCKING | | | SCAC4 |
| 31 | PRXT | PRTI, Pacific Rim Transport, INC | | | SCAC3 |
| 32 | PRXT | PRTI TRANSPORT INC | | | SCAC4 |
| 33 | PRXU | PRAXAIR HELIUM | | USA | BIC |
| 34 | PRXU | Praxair Helium | | | RSRV |
| 35 | PRXU | PRAXAIR INC | | | SCAC4 |
| 36 | PRXV | PREMIER TRANSPORTATION SERVICES LLC | | | SCAC4 |
| 37 | PRXW | PACIFIC RIM TRANSPORT LLC | | | SCAC4 |
| 38 | PRXY | PRANCER TRANSPORT LTD | | | SCAC4 |
