| 1 | PBR | Fast Air Ltd. | Callsign: Polar Bear, | CDN | AVCODES |
| 2 | PBR | Patapsco & Back Rivers R.R. Co. | 1/1950-1/1994; eliminated 10/1999; 7/2000-7/2005 | | NAKINA |
| 3 | PBR | Patapsco & Back Rivers R.R. Co. | 1/52-1/94; eliminated 10/99; 7/2000 | | NRHS |
| 4 | PBR | PATAPSCO & BACK RIVERS RAILROAD CO. | | | PWRC |
| 5 | PBR | Patapsco and Back Rivers Railroad | | | RSRV |
| 6 | PBR | Joux Le Pont-Le Brassus | | CH | TRAFFIC |
| 7 | PBRA | PROFESSIONAL BULL RIDERS INC | | | SCAC4 |
| 8 | PBRC | PERMIAN BASIN RAILROAD CO. | | | PWRC |
| 9 | PBRC | P & B TRUCKING | | | SCAC3 |
| 10 | PBRH | PALI BROTHERS | | | SCAC4 |
| 11 | PBRI | PARABRIS OR TOPTENT | | | SCAC4 |
| 12 | PBRJ | PETROLEO BRASILEIRO S A | | | SCAC3 |
| 13 | PBRJ | PETROLEO BRASILEIRO S A | | | SCAC4 |
| 14 | PBRL | PEROULIS BROS LTD | | | SCAC4 |
| 15 | PBRN | PUERTO BARRIOS COMPANIA NAVIERA S A | | | SCAC3 |
| 16 | PBRO | PETRIG BROS | | | SCAC3 |
| 17 | PBRQ | PORTER BROTHERS INC | | | SCAC3 |
| 18 | PBRR | Pine Belt Southern R.R. Co., Inc. | 7/2000-7/2005 | | NAKINA |
| 19 | PBRR | Pine Belt Southern R.R. Co., Inc. | Jul-00 | | NRHS |
| 20 | PBRR | PINE BELT SOUTHERN RAILROAD | | | PWRC |
| 21 | PBRR | Prairie Belt Railroad | | | RSRV |
| 22 | PBRR | PINE BELT SOUTHERN RAILROAD CO INC | | | SCAC4 |
| 23 | PBRS | PETERS BROS TRUCKING INC | | | SCAC3 |
| 24 | PBRT | PAULSEN BROS TRANS INC | | | SCAC3 |
| 25 | PBRU | PORTABULL STORAGE LLC | | USA | BIC |
| 26 | PBRX | Tyson Fresh Meats | added 7/2006 | | NAKINA |
| 27 | PBRX | TYSON FRESH MEATS | | | PWRC |
| 28 | PBRX | TYSON FRESH MEATS | | | SCAC4 |
| 29 | PBRZ | PACER STACKTRAIN | | | SCAC4 |
