| 1 | GWR | Aura Airlines S.L. t/a Gowair Vaction Airlines | IATA: G6, Callsign: Lemon, Designator G6 recalled by IATA. | E | AVCODES |
| 2 | GWR | Aura Airlines S.L. t/a Gowair Vaction Airlines | Callsign: Lemon, Name changed to Aura Airlines S.L. Designator G6 recalled by IATA. | E | AVCODES |
| 3 | GWR | Aura Airlines S.L. | IATA: U5, Callsign: Lemon, Ceased operation on 27 October 2022. Name changed from Aura Airlines S.L. t/a Gowair Vaction Airlines. Designator G6 recalled by IATA. | E | AVCODES |
| 4 | GWR | Great Western Ry. of Colorado LLC | added 10/2004; 7/2005; eliminated 4/2006 | | NAKINA |
| 5 | GWR | Great Western Ry. Co. | 4/1938-7/2000; eliminated 10/2004 | | NAKINA |
| 6 | GWR | The Great Western Ry. | 7/1923-7/1936 | | NAKINA |
| 7 | GWR | Great Western Ry. Co. | 4/38-7/2000 | | NRHS |
| 8 | GWR | GREAT WESTERN RAILWAY OF COLORADO LLC | | | PWRC |
| 9 | GWR | Great Western Railway of Colorado | | | RSRV |
| 10 | GWR | GREAT WESTERN RAILWAY OF COLORADO L | | | SCAC4 |
| 11 | GWR | Great Western | | USA | TRAFFIC |
| 12 | GWRC | Georgia Woodlands R.R. Co. | 1/1994-7/2000; added 10/2003; 7/2005 | | NAKINA |
| 13 | GWRC | Georgia Woodlands R.R. Co. | 1/94-7/2000 | | NRHS |
| 14 | GWRC | GEORGIA WOODLANDS RAILROAD CO. | | | PWRC |
| 15 | GWRC | Georgia Woodlands Railroad | | | RSRV |
| 16 | GWRC | GEORGIA WOODLANDS RAILROAD CO | | | SCAC4 |
| 17 | GWRN | GRACE, W R & CO - CONN | | | SCAC4 |
| 18 | GWRP | GATEWAY RECYCLING PRODUCTS INC | | | SCAC4 |
| 19 | GWRS | Great Western Ry. Ltd. | 7/2005 | | NAKINA |
| 20 | GWRS | GREAT WEESTERN RAILWAY LTD (GREAT WESTERN RAILWAY OF COLORADO) | | | PWRC |
| 21 | GWRS | Great Western Railway (Saskatchewan) | | | RSRV |
| 22 | GWRS | GREAT WESTERN RAILWAY LTD | | | SCAC4 |
| 23 | GWRT | GOWER TRUCKING | | | SCAC4 |
| 24 | GWRW | GRACE, W.R. & CO. | | | SCAC4 |
| 25 | GWRX | COUNCIL BLUFFS RAILWAY (GREAT WESTERN RAILWAY OF IOWA) | | | PWRC |
