| 6601 | PNVG | PANAMAX NAVEGACAO LTDA - | | | SCAC4 |
| 6602 | PNVI | PETRO-NAV INC | | | SCAC4 |
| 6603 | PNVK | PRONAV SHIP MANAGEMENT GMBH & CO KG | | | SCAC4 |
| 6604 | PNVL | PROSPER NAVIGATION LTD | | | SCAC4 |
| 6605 | PNVN | PORT NAVIGATION INC | | | SCAC3 |
| 6606 | PNVO | PENAVICO | | | SCAC4 |
| 6607 | PNVS | PRONAV SHIP MANAGEMENT INC | | | SCAC4 |
| 6608 | PNVT | PINEHURST MOVING & STORAGE CO | | | SCAC4 |
| 6609 | PNW | Palestinian Airlines | IATA: PF, Callsign: Palestinian, IATA Prefix: 400, Liquidation started in December 2020. | PS | AVCODES |
| 6610 | PNW | Palestinian Airlines | IATA: PF | | ICAO1 |
| 6611 | PNW | The Prescott and Northwestern R.R. Co. | 1/1975-1/1994; eliminated 1/2000; 7/2000-7/2005 | | NAKINA |
| 6612 | PNW | The Prescott and Northwestern R.R. Co. | 1/75-1/94; eliminated 1/2000; 7/2000 | | NRHS |
| 6613 | PNW | PRESCOTT & NORTHWESTERN RAILROAD CO. | | | PWRC |
| 6614 | PNW | Prescott and Northwestern Railroad | | | RSRV |
| 6615 | PNWA | PACIFIC NORTHWEST REF EXPRESS LLC | | | SCAC4 |
| 6616 | PNWC | PACIFIC NORTHWEST CHAPTER-NRHS INC | | | PWRC |
| 6617 | PNWC | PACIFIC NORTHWEST CHAPTER-NAT'L RAI | | | SCAC3 |
| 6618 | PNWC | PACIFIC NORTHWEST CHAPTER-NRHS INC | | | SCAC4 |
| 6619 | PNWE | PACIFIC NORTHWEST ENERGY | | | SCAC4 |
| 6620 | PNWM | PRO NATIONWIDE MOVERS | | | SCAC3 |
| 6621 | PNWO | PORT OF NEW ORLEANS - PORT AUTHORIT | | | SCAC3 |
| 6622 | PNWQ | P AND W CARTAGE | | | SCAC3 |
| 6623 | PNWQ | PACIFIC NORTHWEST EQUIPMENT INC | | | SCAC4 |
| 6624 | PNWR | Portland & Western R.R., Inc. | 7/2000-7/2005 | | NAKINA |
| 6625 | PNWR | Portland & Western R.R., Inc. | Jul-00 | | NRHS |
| 6626 | PNWR | PORTLAND & WESTERN RAILROAD | | | PWRC |
| 6627 | PNWR | Portland and Western Railroad | | | RSRV |
| 6628 | PNWR | PORTLAND & WESTERN RAILROAD INC | | | SCAC4 |
| 6629 | PNWR | Portland & Western | | USA | TRAFFIC |
| 6630 | PNWS | PACIFIC-NATIONAL TRANSPORTATION WAR | | | SCAC3 |
| 6631 | PNWS | PACIFIC-NATIONAL TRANSPORTATION WAR | | | SCAC4 |
| 6632 | PNWT | PREWITT & WALKER TRUCKING COMPANY | | | SCAC3 |
| 6633 | PNWU | PACIFIC NORTHWEST EQUIPMENT INC | | USA | BIC |
| 6634 | PNWU | PACIFIC NORTHWEST EQUIPMENT INC. | | | PWRC |
| 6635 | PNWU | Pacific Northwest Equipment | | | RSRV |
| 6636 | PNWU | RAIL LOGISTICS LC | | | SCAC4 |
| 6637 | PNWX | Pacific Northwest Salvage, Inc. | added 4/1981; eliminated 10/1989 | | NAKINA |
| 6638 | PNWX | Pacific Northwest Salvage, Inc. | added 4/81; eliminated 10/89 | | NRHS |
| 6639 | PNWX | PACIFIC NORTHWEST SALVAGE INC. | | | PWRC |
| 6640 | PNWY | PENN WAY TRUCKING COMPANY | | | SCAC3 |
| 6641 | PNWY | PELEE ISLAND WINERY | | | SCAC4 |
| 6642 | PNX | Imperial Airways, Inc. | Callsign: Phoenix, | USA | AVCODES |
| 6643 | PNX | AIS Airlines B.V. | IATA: IS, Callsign: Spinner, | NL | AVCODES |
| 6644 | PNX | Imperial Airways | | | ICAO1 |
| 6645 | PNX | PORTSMOUTH NAVAL YARD | | | PWRC |
| 6646 | PNXC | PHOENIX CARRIERS INC | | | SCAC3 |
| 6647 | PNXE | PHOENIX TRANSPORTATION LLC | | | SCAC4 |
| 6648 | PNXF | PHOENIX FREIGHT SYSTEMS INC | | | SCAC3 |
| 6649 | PNXF | PHOENIX RACING OF FLORIDA INC | | | SCAC4 |
| 6650 | PNXH | PRINCE TRANSPORT | | | SCAC4 |
| 6651 | PNXI | PIONEER EXPRESS INC | | | SCAC3 |
| 6652 | PNXJ | PROCAN TRANSPORT | | | SCAC4 |
| 6653 | PNXL | PHOENIX LOGISTICS LLC | | | SCAC4 |
| 6654 | PNXM | PHOENIX MEMORIAL PORTRAITS | | | SCAC4 |
| 6655 | PNXN | PACIFIC NATIONAL TRANSPORTATION COR | | | SCAC4 |
| 6656 | PNXO | PN TRANSPORT | | | SCAC4 |
| 6657 | PNXP | P N F EXPRESS | | | SCAC3 |
| 6658 | PNXP | PHOENIX PRINTING & DESIGN INC | | | SCAC4 |
| 6659 | PNXR | PACIFIC NORTH WEST EXPRESS INC | | | SCAC3 |
| 6660 | PNXS | PHOENIX SHIPPING 1986 INC | | | SCAC3 |
| 6661 | PNXS | PHOENIX SHIPPING 1986 INC | | | SCAC4 |
| 6662 | PNXT | PENNEX TRANSPORTATION CO INC | | | SCAC3 |
| 6663 | PNXY | PANAM EXPRESS INC | | | SCAC4 |
| 6664 | PNY | Polish Navy | Callsign: Polish Navy, | PL | AVCODES |
| 6665 | PNY | Polish Navy | | | ICAO1 |
| 6666 | PNYA | PONY EXPRESS LLC | | | SCAC4 |
| 6667 | PNYD | PENNEYS DRIVE A WAY INC | | | SCAC3 |
| 6668 | PNYI | PORT OF NEW YORK EXPRESS CO INC | | | SCAC3 |
| 6669 | PNYO | PORT OF NY CARTAGE CO | | | SCAC3 |
| 6670 | PNYP | PINEY POINT TRANSPORTATION COMPANY | | | SCAC3 |
| 6671 | PNYP | PAINTED PONY EXPRESS INC | | | SCAC4 |
| 6672 | PNYQ | PENNYPACKER, JAMES G | | | SCAC3 |
| 6673 | PNYR | PONY EXPRESS | | | SCAC4 |
| 6674 | PNYSA | PKS w Nysie Sp. z o.o. | | PL | TRAFFIC |
| 6675 | PNZL | PENZOIL-QUAKER STATE CO | | | SCAC4 |
| 6676 | PNZT | P & Z TRUCKING COMPANY INC | | | SCAC3 |
| 6677 | PNZU | PETROLEUM CORP. OF NEW ZEALAND | | | SCAC3 |
| 6678 | PO | Polar Air Cargo, Inc. | ICAO: PAC, Callsign: Polar, IATA Prefix: 403, Name changed to Polar Air Cargo Worldwide, Inc. ICAO Callsign changed from Polar Tiger | USA | AVCODES |
| 6679 | PO | Protea Lugdiens (EDMS.) BPK | Callsign: Protea, | ZA | AVCODES |
| 6680 | PO | Polar Air Cargo, Inc. | ICAO: PAC, Callsign: Polar Tiger, IATA Prefix: 403, ICAO Callsign changed to Polar | USA | AVCODES |
| 6681 | PO | Aeropelican Air Services Pty Ltd. | ICAO: PEL, Designator PO recalled by IATA. Established on 23 October 1968 and started operations on 1 July 1971. | AUS | AVCODES |
| 6682 | PO | Polar Air Cargo Worldwide, Inc. | ICAO: PAC, Callsign: Polar, IATA Prefix: 403, Name changed from Polar Air Cargo, Inc. ICAO Callsign changed from Polar Tiger | USA | AVCODES |
| 6683 | PO | Compagnie du chemin de fer Paris et Orléans | | F | TRAFFIC |
| 6684 | POA | Portuguese Army | Callsign: Portuguese Army, | P | AVCODES |
| 6685 | POA | Portuguese Army | | | ICAO1 |
| 6686 | POAA | POLAR TRANSPORT | | | SCAC4 |
| 6687 | POAB | PROFILES AB | | | SCAC3 |
| 6688 | POAC | POOLE AIR COURIERS | | | SCAC3 |
| 6689 | POAC | POIRIER, SERGE | | | SCAC4 |
| 6690 | POAD | POOLE, A D TRANSPORTATION CO INC | | | SCAC3 |
| 6691 | POAE | POL-TRAILER CORP | | | SCAC4 |
| 6692 | POAF | PORTLAND AIR FREIGHT INC | | | SCAC3 |
| 6693 | POAF | PORTLAND AIR FREIGHT INC | | | SCAC4 |
| 6694 | POAG | PRO AG TRANSPORT INC | | | SCAC3 |
| 6695 | POAJ | PROA INTERNACIONAL Y LOGISTICA SA D | | | SCAC4 |
| 6696 | POAK | Port of Oakland Ry. | 1/1980-7/2005 | | NAKINA |
| 6697 | POAK | Port of Oakland Ry. | 1/80-7/2000 | | NRHS |
| 6698 | POAK | PORT OF OAKLAND RAILWAY | | | PWRC |
| 6699 | POAK | Port of Oakland Railway | | | RSRV |
| 6700 | POAK | PORT OF OAKLAND RAILWAY | | | SCAC3 |
