| 1 | THR | Tehran Airline | Callsign: Tehran Air, | IR | AVCODES |
| 2 | THR | Tehran Airline | | | ICAO1 |
| 3 | THR | Tenryu Hamanako Railroad | | J | TRAFFIC |
| 4 | THRA | TRANSPORTES HUGO ROMAN ANAYA | | | SCAC4 |
| 5 | THRB | THORNBURG BROTHERS INC | | | SCAC4 |
| 6 | THRC | TRANSPORTADORA HRH SA DE CV | | | SCAC4 |
| 7 | THRD | TRANSPORT HAROLD INC | | | SCAC4 |
| 8 | THRE | THREE I TRUCK LINE, INC | | | SCAC1 |
| 9 | THRI | THREE RIVERS TRUCKING INC | | | SCAC4 |
| 10 | THRN | THR AND ASSOCIATES INC | | | SCAC4 |
| 11 | THRO | THUNDERROLLS INC | | | SCAC4 |
| 12 | THRP | THURSTON TRANSPORTATION | | | SCAC4 |
| 13 | THRQ | THRILL MASTERS INC | | | SCAC4 |
| 14 | THRS | THORESEN & CO (BANGKOK) LTD | | | SCAC4 |
| 15 | THRT | THRIFT TRUCKING, INC | | | SCAC1 |
| 16 | THRT | THRIFT TRUCKING | | | SCAC4 |
| 17 | THRW | THREE WAY TRANSFER, INC | | | SCAC1 |
| 18 | THRW | THREE WAY | | | SCAC4 |
| 19 | THRX | Transportation Corp. of America | added 7/1999; 7/2000-7/2005 | | NAKINA |
| 20 | THRX | Transportation Corp. of America | added 7/99; 7/2000 | | NRHS |
| 21 | THRX | TRANSPORTATION CORPORATION OF AMERICA | | | PWRC |
| 22 | THRX | TENNESSEE HOLSTON RAILWAY | | | PWRC |
| 23 | THRX | Transportation of America | | | RSRV |
| 24 | THRX | TRANSPORTATION CORPORATION OF AMERI | | | SCAC4 |
| 25 | THRY | TRANSPORT HENRI ROY ENR | | | SCAC4 |