| 1 | GTR | Galistair Trading Limited | IATA: GH, Callsign: Galister, | M | AVCODES |
| 2 | GTR | Gestar | | | ICAO1 |
| 3 | GTR | Great River R.R. Rosedale-Bolivar County Port Commission | added 1/1984; 1/1994-7/2005 | | NAKINA |
| 4 | GTR | Great River R.R. Rosedale-Bolivar County Port Commission | 1/94-7/2000 | | NRHS |
| 5 | GTR | GREAT RIVER RAILROAD d/b/a ROSEDALE-BOLIVAR COUNTY PORT COMMISSION | | | PWRC |
| 6 | GTR | Great River Railroad (Rosedale-Bolivar County Port Commission) | | | RSRV |
| 7 | GTR | Greentrains | | AUS | TRAFFIC |
| 8 | GTR | Goldschmidt Thermit Railservice (Österreich) GmbH | | AT | VKM |
| 9 | GTRA | Golden Triangle R.R. | added 7/1982; 1/1994-7/2005 | | NAKINA |
| 10 | GTRA | Golden Triangle R.R. | added 7/82; 1/94-7/2000 | | NRHS |
| 11 | GTRA | GOLDEN TRIANGLE RAILROAD | | | PWRC |
| 12 | GTRA | Golden Triangle Railroad | | | RSRV |
| 13 | GTRA | GOLDEN TRIANGLE RAILROAD | | | SCAC4 |
| 14 | GTRA | Golden Triangle R.R. | | USA | TRAFFIC |
| 15 | GTRE | GRANT TRUCKING | | | SCAC4 |
| 16 | GTRI | GRANTIER OIL CO INC | | | SCAC4 |
| 17 | GTRJ | GRANTS TRANSPORT LIMITED | | | SCAC4 |
| 18 | GTRK | G & T TRUCKING | | | SCAC4 |
| 19 | GTRM | | ~Sorin Oprisan | GB | TRAFFIC |
| 20 | GTRO | GREENSVILLE TRANSPORT COMPANY | | | SCAC4 |
| 21 | GTRP | GUARDIAN TRANSPORTATION CORPORATION | | | SCAC4 |
| 22 | GTRR | GTR TRANSPORT | | | SCAC4 |
| 23 | GTRS | GLOBETROTTER TRANSPORT SERVICES | | | SCAC4 |
| 24 | GTRT | GTRV-USA INC | | | SCAC4 |
| 25 | GTRU | GENTENAAR TRANSPORT BV | | NL | BIC |
| 26 | GTRW | GATOR PLANT CO | | | SCAC4 |
| 27 | GTRX | The Goodyear Tire & Rubber Co. | 8/1920-7/1930 | | NAKINA |
| 28 | GTRX | GOODYEAR TIRE & RUBBER CO. | | | PWRC |
| 29 | GTRY | GENTRY TRUCKING | | | SCAC4 |
