| 4501 | THLR | THOMAS, LOREN O | | | SCAC3 |
| 4502 | THLR | THALER OIL CO INC | | | SCAC4 |
| 4503 | THLS | THATCHER LIMOUSINE SERVICE | | | SCAC3 |
| 4504 | THLS | TRANSTECH LOGISTICS | | | SCAC4 |
| 4505 | THLU | TRAVERWAY MARITIME LTD | | | SCAC3 |
| 4506 | THLV | THAMES LIVERY CORP LTD | | | SCAC3 |
| 4507 | THLY | TAYLOR HAULING LLC | | | SCAC4 |
| 4508 | THM | Thai Global Airline Company Limited | IATA: YH, Callsign: Thai Global, Ceased operations | T | AVCODES |
| 4509 | THM | Airmark Aviation | | | ICAO1 |
| 4510 | THM | Train Hungary Magánvasút Kft | | H | TRAFFIC |
| 4511 | THM | Train Hungary Magánvasút Kft | | HU | VKM |
| 4512 | THMA | THIBODEAU, MARTIN | | | SCAC4 |
| 4513 | THMB | THOMPSON, BILL TRANSPORT INC | | | SCAC4 |
| 4514 | THME | THOMAS & THOMAS ENTERPRISE LLC | | | SCAC4 |
| 4515 | THMH | THERMO DISTRIBUTION INC | | | SCAC4 |
| 4516 | THMI | THOMPSON TRUCKING CO INC | | | SCAC4 |
| 4517 | THMK | THERMO KING OF FARGO | | | SCAC4 |
| 4518 | THML | THOMPSON TRUCKING L C | | | SCAC4 |
| 4519 | THMN | THYSSEN MINING | | | SCAC4 |
| 4520 | THMS | THOMAS AND SONS | | | SCAC4 |
| 4521 | THMW | THOMAS, WILLIAM, TRUCKING, INCORPORATED | | | SCAC1 |
| 4522 | THN | International Security Assistance Force | Callsign: Athena, | CDN | AVCODES |
| 4523 | THN | International Security Assistance Force | | | ICAO1 |
| 4524 | THNA | TECHNIC CANADA | | | SCAC4 |
| 4525 | THNB | TECHO-BLOC INC | | | SCAC4 |
| 4526 | THNC | THOMAS ENTERPRISES OF GREENSBORO IN | | | SCAC4 |
| 4527 | THNH | TMCL HOLDING NV | | | SCAC4 |
| 4528 | THNI | TALHAN TRANSPORT INC | | | SCAC4 |
| 4529 | THNJ | THOM-TRANS INC | | | SCAC4 |
| 4530 | THNM | THORNTON, MIKE TRUCKING INC | | | SCAC4 |
| 4531 | THNN | TRAUSCH ENTERPRISES INC | | | SCAC4 |
| 4532 | THNO | TECHNIP UK LIMITED | | | SCAC4 |
| 4533 | THNQ | THINNES TRANSPORT INC | | | SCAC4 |
| 4534 | THNS | THOMASON EXPRESS LLC | | | SCAC4 |
| 4535 | THNT | THORNTONS INC | | | SCAC4 |
| 4536 | THNU | CHENGDU TIANHAN SUPPLY CHAIN MANAGEMENT CO. LTD. | | PRC | BIC |
| 4537 | THNV | THORN TREE TECHNOLOGY CORP | | | SCAC4 |
| 4538 | THNW | THREE R (3R) OF CHARLESTON INC | | | SCAC4 |
| 4539 | THNY | THORNLEY OIL COMPANY INC | | | SCAC4 |
| 4540 | THO | Transportes Aereos Centroamericanos de Honduras (TACA de Honduras) | Callsign: Lempira, | HN | AVCODES |
| 4541 | THO | Thro Aviation, Inc. d/b/a ZEN Flight | Callsign: Thro, ICAO designator changed to XEN. ICAO Callsign changed to Zen Jet. | USA | AVCODES |
| 4542 | THO | TACA De Honduras | | | ICAO1 |
| 4543 | THOA | TRANSPORTES HO SA DE CV | | | SCAC4 |
| 4544 | THOB | THOMPSON, BRAD | | | SCAC4 |
| 4545 | THOC | THOMSEN OIL CO | | | SCAC4 |
| 4546 | THOE | THOMPSON & SONS ENTERPRISES INC | | | SCAC4 |
| 4547 | THOJ | THORNLEY ENTERPRISES INC | | | SCAC4 |
| 4548 | THOL | THOMS TRANSPORT CO INC | | | SCAC4 |
| 4549 | THOM | THOMSON TERMINALS LIMITED | | | SCAC4 |
| 4550 | THOO | THOMAS TRUCKING INC | | | SCAC4 |
| 4551 | THOP | THREE-O MANUFACTURING INC | | | SCAC4 |
| 4552 | THOR | THORSONS MARKETING ASSOCIATES CANAD | | | SCAC4 |
| 4553 | THOS | THOR SHIPPING LIMITED | | | SCAC4 |
| 4554 | THOT | TEXAS HOT SHOT CO | | | SCAC4 |
| 4555 | THOW | THOMPSON MOTOR COACH | | | SCAC4 |
| 4556 | THOY | TALLY HO INC | | | SCAC4 |
| 4557 | THPA | THROOP PROPANE CO | | | SCAC4 |
| 4558 | THPB | THOMPSON-ARTHUR PAVING | | | SCAC4 |
| 4559 | THPC | THX TRANSPORT LLC | | | SCAC4 |
| 4560 | THPD | THOMPSON, DAVID, TRUCKING COMPANY | | | SCAC1 |
| 4561 | THPD | THOMPSON, DAVID TRUCKING COMPANY | | | SCAC4 |
| 4562 | THPJ | THOMPSON, JOE E | | | SCAC1 |
| 4563 | THPK | THOMPSON TRUCKING COMPANY | | | SCAC4 |
| 4564 | THPL | THIBODEAU, PAUL | | | SCAC4 |
| 4565 | THPQ | TRANSPORTES HILDA PATRICIA QUINTANI | | | SCAC4 |
| 4566 | THPS | THOMPSON, JAMES W TRUCKING | | | SCAC4 |
| 4567 | THPT | THOMPSON TRANSPORTATION COMPANY INC | | | SCAC4 |
| 4568 | THPU | ITALMATCH CHEMICALS S.P.A. | | I | BIC |
| 4569 | THPU | THERMPHOS INTERNATIONAL | | | SCAC4 |
| 4570 | THPY | THOMPSON TRANSPORTATION | | | SCAC4 |
| 4571 | THPZ | THOMAS HILL POWER PLANT | | | PWRC |
| 4572 | THQF | THREE FIVE FIVE SIX NINE SEVEN TWO | | | SCAC4 |
| 4573 | THQL | THUNDER LOGISTICS INC | | | SCAC4 |
| 4574 | THQN | THOMPSON, RON | | | SCAC4 |
| 4575 | THQP | THOMAS PETROLEUM INC | | | SCAC4 |
| 4576 | THQR | THOMAS TOURS | | | SCAC4 |
| 4577 | THQT | T H TRANSPORT INC | | | SCAC4 |
| 4578 | THQU | THOR QUIMICOS DE MEXICO, SA DE CV | | MEX | BIC |
| 4579 | THQU | Thor Quimicos De Mexico | | | RSRV |
| 4580 | THQU | THOR QUIMICOS DE MEXICO SA DE | | | SCAC4 |
| 4581 | THR | Tehran Airline | Callsign: Tehran Air, | IR | AVCODES |
| 4582 | THR | Tehran Airline | | | ICAO1 |
| 4583 | THR | Tenryu Hamanako Railroad | | J | TRAFFIC |
| 4584 | THRA | TRANSPORTES HUGO ROMAN ANAYA | | | SCAC4 |
| 4585 | THRB | THORNBURG BROTHERS INC | | | SCAC4 |
| 4586 | THRC | TRANSPORTADORA HRH SA DE CV | | | SCAC4 |
| 4587 | THRD | TRANSPORT HAROLD INC | | | SCAC4 |
| 4588 | THRE | THREE I TRUCK LINE, INC | | | SCAC1 |
| 4589 | THRI | THREE RIVERS TRUCKING INC | | | SCAC4 |
| 4590 | THRN | THR AND ASSOCIATES INC | | | SCAC4 |
| 4591 | THRO | THUNDERROLLS INC | | | SCAC4 |
| 4592 | THRP | THURSTON TRANSPORTATION | | | SCAC4 |
| 4593 | THRQ | THRILL MASTERS INC | | | SCAC4 |
| 4594 | THRS | THORESEN & CO (BANGKOK) LTD | | | SCAC4 |
| 4595 | THRT | THRIFT TRUCKING, INC | | | SCAC1 |
| 4596 | THRT | THRIFT TRUCKING | | | SCAC4 |
| 4597 | THRW | THREE WAY TRANSFER, INC | | | SCAC1 |
| 4598 | THRW | THREE WAY | | | SCAC4 |
| 4599 | THRX | Transportation Corp. of America | added 7/1999; 7/2000-7/2005 | | NAKINA |
| 4600 | THRX | Transportation Corp. of America | added 7/99; 7/2000 | | NRHS |
