| 1 | WTS | W.A.T.S. Ltd. | Callsign: Watts, Ceased operations 1990 | GB | AVCODES |
| 2 | WTSC | WOOLARD TRUCK SERVICE LLC | | | SCAC4 |
| 3 | WTSD | W T S EXPRESS INC | | | SCAC4 |
| 4 | WTSE | West Shore R.R. Corp. | added 10/1985; 1/1994; eliminated 4/2000; 7/2000-7/2005 | | NAKINA |
| 5 | WTSE | West Shore R.R. Corp. | 1/94; eliminated 4/2000; 7/2000 | | NRHS |
| 6 | WTSE | WEST SHORE RAILROAD CORP. | | | PWRC |
| 7 | WTSE | West Shore Railroad | | | RSRV |
| 8 | WTSG | WATSON TRUCKING | | | SCAC4 |
| 9 | WTSI | WES-TEX SERVICES INC | | | SCAC4 |
| 10 | WTSJ | WATCO CO | | | SCAC4 |
| 11 | WTSK | WALSHAK TRUCK SERVICES | | | SCAC4 |
| 12 | WTSN | WATSON, SAM TRUCKING INC | | | SCAC4 |
| 13 | WTSP | WATTS, BRUCE E PLUMBING & HEATING | | | SCAC4 |
| 14 | WTST | WELLING TRANSPORTATION SYSTEMS | | | SCAC4 |
| 15 | WTSU | WEIGAND-GRUNDSTUCKS GMBH & CO. KG | | D | BIC |
| 16 | WTSW | WT TRANSPORTATION SERVICES LLC | | | SCAC4 |
| 17 | WTSX | WEST SHORE RAILWAY SERVICES, INC. | | | PWRC |
| 18 | WTSY | WITHERS/SUDDATH RELOCATION SYSTEMS | | | SCAC4 |
