| 1 | PAR | Spair Air Transport Corporation | Callsign: Spair, | RUS | AVCODES |
| 2 | PAR | Pacific Rim Airways PTY Ltd. | Callsign: Pacrim, | AUS | AVCODES |
| 3 | PAR | Partner Air Services A/S | Callsign: Partnerair, Name changed to Partnair A/S | N | AVCODES |
| 4 | PAR | Partnair A/S | Callsign: Partnerair, Name changed from Partner Air Services A/S | N | AVCODES |
| 5 | PAR | Pacific Rim Airways | | | ICAO1 |
| 6 | PAR | PACIFIC RAILWAY SOCIETY INC | | | PWRC |
| 7 | PAR | | City: Paris | F | TRAFFIC |
| 8 | PARA | PARAMOUNT EXPRESS OF PATERSON INC | | | SCAC3 |
| 9 | PARAC | Parachini SA (Sersa Group) | | CH | VKM |
| 10 | PARB | PARKER BROTHERS, INC | | | SCAC3 |
| 11 | PARC | CONSOLIDATED RAIL CORP. [PENNSYLVANIA & ATLANTIC RAILROAD CO.] | | | PWRC |
| 12 | PARC | PARCEL DELIVERY, INC | | | SCAC3 |
| 13 | PARD | PARADISE TRUCKING INC | | | SCAC3 |
| 14 | PARD | Pardubice | | CZ | TRAFFIC |
| 15 | PARE | PARE TRANSPORT CO, INC | | | SCAC3 |
| 16 | PARF | PARRAS TRUCKING | | | SCAC4 |
| 17 | PARG | PARR, GEORGE TRUCKING SERVICE INC | | | SCAC3 |
| 18 | PARG | PARGA TRUCKING | | | SCAC4 |
| 19 | PARH | PARISH OIL CO INC | | | SCAC4 |
| 20 | PARI | PARADIS INC | | | SCAC4 |
| 21 | PARK | PARK TRUCKING COMPANY, THE | | | SCAC3 |
| 22 | PARLA | Tranvia de Parla | City: Parla | E | TRAFFIC |
| 23 | PARN | PACIFIC & ARCTIC RAILROAD & NAVIGATION CO. | | | PWRC |
| 24 | PARN | PARROTT TRANSPORT COMPANY INC, THE | | | SCAC4 |
| 25 | PARO | PARSON, JACK B COMPANIES | | | SCAC4 |
| 26 | PARP | PARAMETERS UNLIMITED | | | SCAC3 |
| 27 | PARP | PARKERS PROPANE | | | SCAC4 |
| 28 | PARQ | P & R TRANSFER INC | | | SCAC3 |
| 29 | PARR | PARKER, RICHARD, INC | | | SCAC3 |
| 30 | PARS | PACIFIC RELOCATING SERVICES INC | | | SCAC3 |
| 31 | PART | PARIS TRUCKING COMPANY INC | | | SCAC4 |
| 32 | PARTL | Партнер Лизинг АД | | BG | VKM |
| 33 | PARU | PARAGUAY LINIE SCHIFFAHRTGESELL | | | SCAC3 |
| 34 | PARV | PARKHURST, VIRGIL | | | SCAC3 |
| 35 | PARW | PEARCE WORLDWIDE LOGISITCS INC | | | SCAC4 |
| 36 | PARX | Pan American Ry. Co. | added 4/1975; 1/1980-7/2005 | | NAKINA |
| 37 | PARX | Union Tank Car Co. | 10/1957; added 1/1958; 4/1961-10/1966; eliminated 10/1968 | | NAKINA |
| 38 | PARX | Sinclair Refining Co. | 7/1937-7/1954; eliminated 1/1958 | | NAKINA |
| 39 | PARX | Producers & Refiners Corp. (Sinclair Refining Co.) | 7/1935 | | NAKINA |
| 40 | PARX | Producers & Refiners Corp. | 7/1923-7/1932 | | NAKINA |
| 41 | PARX | Pan-American Refining Co. | 8/1920 | | NAKINA |
| 42 | PARX | Producers & Refiners Corp. (Sinclair Refining Co.) | Apr-38 | | NRHS |
| 43 | PARX | Sinclair Refining Co. | 1/52; eliminated 1/58 | | NRHS |
| 44 | PARX | Union Tank Car Co. | 10/57; added 1/58; 4/61-10/66; eliminated 10/68 | | NRHS |
| 45 | PARX | Pan American Ry. Co. | added 4/75; 1/80-7/2000 | | NRHS |
| 46 | PARX | *SINCLAIR REFINING CO. [PRODUCERS & REFINERS CORP.; PAN-AMERICAN REFINING CO.] | | | PWRC |
| 47 | PARX | *BLUE MOUNTAIN RAILROAD, INC. [PALOUSE RIVER RAILROAD CO.] | | | PWRC |
| 48 | PARX | +PAN AMERICAN RAILWAY COMPANY (UNION TANK CAR CO.) | | | PWRC |
| 49 | PARX | Pan American Railway | | | RSRV |
| 50 | PARX | PAN AMERICAN RAILWAY COMPANY | | | SCAC4 |
| 51 | PARX | Pan American Railway Copany | | USA | TRAFFIC |
| 52 | PARY | Prairie Trunk Ry. | 1/1980; added 4/1980; eliminated 10/1987 | | NAKINA |
| 53 | PARY | Prairie Trunk Ry. | 1/80; added 4/80; eliminated 10/87 | | NRHS |
| 54 | PARY | RETIRED 01-19-90 DMC (0777) [PRAIRIE TRUNK RY.] | | | PWRC |
| 55 | PARY | Prairie Trunk Railway | | | RSRV |
| 56 | PARY | PARRY, C D CO INC | | | SCAC4 |
| 57 | PARZ | PARK INDUSTRIES | | | PWRC |
