| 1 | WTC | Weasua Air Transport Company Limited (WATCO) | Callsign: Watco, | LB | AVCODES |
| 2 | WTC | Weasua Air Transport Company | | | ICAO1 |
| 3 | WTC | WEYERHAUSER TIMBER CO. | | | PWRC |
| 4 | WTCA | WALCOTT, PETER E & ASSOCIATES LIMIT | | | SCAC4 |
| 5 | WTCD | WESTCAN AIRCRAFT SALES & SALVAGE LT | | | SCAC4 |
| 6 | WTCL | WESTRAN INC | | | SCAC4 |
| 7 | WTCM | WORLD TRAFFIC DE MEXICO | | | SCAC4 |
| 8 | WTCN | WESTERN TRANSPORTATION CO INC | | | SCAC4 |
| 9 | WTCO | Western Transportation Co. | 1/1975-7/2005 | | NAKINA |
| 10 | WTCO | Western Transportation Co. | 1/75-7/2000 | | NRHS |
| 11 | WTCO | WESTERN TRANSPORTATION CO. | | | PWRC |
| 12 | WTCO | Western Transportation | | | RSRV |
| 13 | WTCO | WHEELING TRANSPORTATION COMPANY INC | | | SCAC4 |
| 14 | WTCQ | WASTECO | | | SCAC4 |
| 15 | WTCS | WILLIAMS TRUCKING CO INC | | | SCAC4 |
| 16 | WTCV | WTC | | | SCAC4 |
| 17 | WTCW | WOLSIFER TRUCKING LLC | | | SCAC4 |
| 18 | WTCX | Weyerhauser Timber Co. | added 10/1958; eliminated 1/1960 | | NAKINA |
| 19 | WTCX | Weyerhauser Co. | added 1/1960; 4/1961-4/1970; eliminated 4/1974 | | NAKINA |
| 20 | WTCX | Atlantic Terminals Inc. | added 4/1974; 1/1975; eliminated 4/1977 | | NAKINA |
| 21 | WTCX | Weyerhauser Co. | added 4/1977; 1/1980-7/2000; eliminated 10/2000; 7/2005 (not listed) | | NAKINA |
| 22 | WTCX | Weyerhauser Timber Co. | added 10/58; eliminated 1/60 | | NRHS |
| 23 | WTCX | Weyerhauser Co. | added 1/60; 4/61-4/70 | | NRHS |
| 24 | WTCX | Atlantic Terminals Inc. | Jan-75 | | NRHS |
| 25 | WTCX | Weyerhauser Co. | 1/80-7/2000; eliminated 10/2000 | | NRHS |
| 26 | WTCX | WEYERHAUSER COMPANY (ATLANTIC TERMINALS, INC.) | | | PWRC |
| 27 | WTCX | Weyerhaeuser | | | RSRV |
| 28 | WTCY | WELBORN TRUCKING CO INC | | | SCAC4 |
