| 1 | WT | Nigeria Airways Ltd. | ICAO: NGA, Callsign: Nigeria, IATA Prefix: 087, Ceased operations | WAN | AVCODES |
| 2 | WT | Wasaya Airways L.P. | ICAO: WSG, Callsign: Wasaya, Designator WT recalled by IATA. IATA designator changed from WG*. Name changed from Wasaya Airways Ltd. | CDN | AVCODES |
| 3 | WT | Swiftair, S.A. | ICAO: SWT, Callsign: Swift, IATA Prefix: 227, | E | AVCODES |
| 4 | WT | Swiftair, S.A. | ICAO: SWT, Callsign: Swift, IATA Prefix: 221, IATA Prefix code changed from 227. | E | AVCODES |
| 5 | WT | Weldwood Transportation Ltd. | 1/1975-1/1980 | | NAKINA |
| 6 | WT | Weldwood Transportation Ltd. | 1/75-1/80 | | NRHS |
| 7 | WT | *WELDWOOD TRANSPORTATION LTD. | | | PWRC |
| 8 | WT | *WICHITA TERMINAL | | | PWRC |
| 9 | WT | Weldwood Transportation | | | RSRV |
| 10 | WT | WELDWOOD TRANSPORTATION LIMITED | | | SCAC4 |
| 11 | WTA | Africa West | IATA: 3L, Callsign: West Togo, IATA Prefix: 858, Designator 3L* recalled by IATA | TG | AVCODES |
| 12 | WTA | Africa West | IATA: FK, Callsign: West Togo, IATA Prefix: 858, Designator FK recalled by IATA. IATA Desginator changed from FK*. Designator 3L* recalled by IATA | TG | AVCODES |
| 13 | WTA | Africa West | IATA: FK, Callsign: West Togo, IATA Prefix: 858, IATA Desginator changed to FK. Designator 3L* recalled by IATA | TG | AVCODES |
| 14 | WTA | Africa West | IATA: FK | | ICAO1 |
| 15 | WTA | WICHITA TERMINAL ASSOCIATION | | | PWRC |
| 16 | WTA | WICHITA TERMINAL ASSOCIATION | | | SCAC4 |
| 17 | WTAC | WILLIAMS TRUCKING | | | SCAC4 |
| 18 | WTAE | WILCO TRANSPORTATION SERVICES INC | | | SCAC4 |
| 19 | WTAG | WARDEN FARMS TRUCKING LLC | | | SCAC4 |
| 20 | WTAH | WESTERN TRANSPORTATION SERVICES LLC | | | SCAC4 |
| 21 | WTAK | WHITLOW TRUCKING | | | SCAC4 |
| 22 | WTAL | WORLDTRANS AIR-SEA SERVICE LTD | | | SCAC4 |
| 23 | WTAP | WALLACE TRANSPORT | | | SCAC1 |
| 24 | WTAP | WALLACE TRANSPORT | | | SCAC4 |
| 25 | WTAQ | WALLER TRANSPORT & EQUIPMENT INC | | | SCAC4 |
| 26 | WTAR | WHITETAIL TRUCKING INC | | | SCAC4 |
| 27 | WTAS | WESTERN TRAILER SERVICE INC | | | SCAC4 |
| 28 | WTAU | WILTRADING PTY LTD | | | SCAC4 |
| 29 | WTAV | WESTS TRANSPORTATION SOLUTIONS LLC | | | SCAC4 |
| 30 | WTAW | WIREDTIME.COM INC | | | SCAC4 |
| 31 | WTB | Wutachtalbahn e.V. | Fützen | D | privat-bahn.de |
| 32 | WTB | Dampflok-Gemeinschaft 41096 e.V | | DE | VKM |
| 33 | WTBA | WALLEY'S TRUCKING | | | SCAC4 |
| 34 | WTBB | Stadt Blumberg-Wutachtalbahn | | DE | VKM |
| 35 | WTBC | West Towns Bus Company | City: Chicago | USA | TRAFFIC |
| 36 | WTBJ | WEBB TRANSPORT LLC | | | SCAC4 |
| 37 | WTBM | WELLS TRUCKING | | | SCAC4 |
| 38 | WTBN | WILSON TRANSPORT SERVICE LLC | | | SCAC4 |
| 39 | WTBO | WAREHOUSE TRANSPORT ASSOCIATES INC | | | SCAC4 |
| 40 | WTBS | WATTS BROTHERS MOVING & STORAGE SYS | | | SCAC4 |
| 41 | WTBT | WALL TO WALL ENTERPRISES INC | | | SCAC4 |
| 42 | WTBV | WINEBARGER TRUCKING | | | SCAC4 |
| 43 | WTBY | WILLIAMS TRANSPORTATION | | | SCAC4 |
| 44 | WTC | Weasua Air Transport Company Limited (WATCO) | Callsign: Watco, | LB | AVCODES |
| 45 | WTC | Weasua Air Transport Company | | | ICAO1 |
| 46 | WTC | WEYERHAUSER TIMBER CO. | | | PWRC |
| 47 | WTCA | WALCOTT, PETER E & ASSOCIATES LIMIT | | | SCAC4 |
| 48 | WTCD | WESTCAN AIRCRAFT SALES & SALVAGE LT | | | SCAC4 |
| 49 | WTCL | WESTRAN INC | | | SCAC4 |
| 50 | WTCM | WORLD TRAFFIC DE MEXICO | | | SCAC4 |
| 51 | WTCN | WESTERN TRANSPORTATION CO INC | | | SCAC4 |
| 52 | WTCO | Western Transportation Co. | 1/1975-7/2005 | | NAKINA |
| 53 | WTCO | Western Transportation Co. | 1/75-7/2000 | | NRHS |
| 54 | WTCO | WESTERN TRANSPORTATION CO. | | | PWRC |
| 55 | WTCO | Western Transportation | | | RSRV |
| 56 | WTCO | WHEELING TRANSPORTATION COMPANY INC | | | SCAC4 |
| 57 | WTCQ | WASTECO | | | SCAC4 |
| 58 | WTCS | WILLIAMS TRUCKING CO INC | | | SCAC4 |
| 59 | WTCV | WTC | | | SCAC4 |
| 60 | WTCW | WOLSIFER TRUCKING LLC | | | SCAC4 |
| 61 | WTCX | Weyerhauser Timber Co. | added 10/1958; eliminated 1/1960 | | NAKINA |
| 62 | WTCX | Weyerhauser Co. | added 1/1960; 4/1961-4/1970; eliminated 4/1974 | | NAKINA |
| 63 | WTCX | Atlantic Terminals Inc. | added 4/1974; 1/1975; eliminated 4/1977 | | NAKINA |
| 64 | WTCX | Weyerhauser Co. | added 4/1977; 1/1980-7/2000; eliminated 10/2000; 7/2005 (not listed) | | NAKINA |
| 65 | WTCX | Weyerhauser Timber Co. | added 10/58; eliminated 1/60 | | NRHS |
| 66 | WTCX | Weyerhauser Co. | added 1/60; 4/61-4/70 | | NRHS |
| 67 | WTCX | Atlantic Terminals Inc. | Jan-75 | | NRHS |
| 68 | WTCX | Weyerhauser Co. | 1/80-7/2000; eliminated 10/2000 | | NRHS |
| 69 | WTCX | WEYERHAUSER COMPANY (ATLANTIC TERMINALS, INC.) | | | PWRC |
| 70 | WTCX | Weyerhaeuser | | | RSRV |
| 71 | WTCY | WELBORN TRUCKING CO INC | | | SCAC4 |
| 72 | WTD | | City: Woltersdorf | D | TRAFFIC |
| 73 | WTDA | WASHINGTON TRUCKING | | | SCAC4 |
| 74 | WTDB | WALLENIUS TRANSROLL DO BRASIL LTDA | | | SCAC4 |
| 75 | WTDE | WADE TRUCKING LLC | | | SCAC4 |
| 76 | WTDI | WEE-TOTE DELIVERY SSERVICES | | | SCAC4 |
| 77 | WTDK | WESTERN TRANSPORT | | | SCAC4 |
| 78 | WTDR | WESTON TRANSPORTATION & LOGISTICS | | | SCAC4 |
| 79 | WTDS | W T DISTRIBUTORS INC | | | SCAC4 |
| 80 | WTDV | WEST TRUCKING INC | | | SCAC4 |
| 81 | WTDW | WALLER TRUCKING LLC | | | SCAC4 |
| 82 | WTEC | WATERTEC IRRIGATION LTD | | | SCAC4 |
| 83 | WTEI | WILMER TOURS AND EXECUTIVE | | | SCAC4 |
| 84 | WTEJ | WALLACE TRUCKING | | | SCAC4 |
| 85 | WTEL | WEST TO EAST LOGISTICS | | | SCAC4 |
| 86 | WTEM | WILSON TRUCKING SERVICE INC | | | SCAC4 |
| 87 | WTEN | WEST TEXAS EXPRESS INC | | | SCAC4 |
| 88 | WTEO | WHITE OIL COMPANY LLC | | | SCAC4 |
| 89 | WTEP | WESTEX, INC | | | SCAC1 |
| 90 | WTEQ | WILDCAT TRUCKING ENTERPRISES INC | | | SCAC4 |
| 91 | WTER | WINTER GARDENS QUALITY FOODS | | | SCAC4 |
| 92 | WTEU | WORLD WIDE TRANSPORT | | | SCAC4 |
| 93 | WTEV | WTS TRANSPORTATION SERVICES LLC | | | SCAC4 |
| 94 | WTEW | WORLDWIDE TRUCKING EXPEDITORS INC | | | SCAC4 |
| 95 | WTEX | WASTE CONTROL SPECIALISTS LLC | | | SCAC4 |
| 96 | WTF | West African Air Transport | Callsign: Westaf Airtrans, | SN | AVCODES |
| 97 | WTF | West African Air Transport | | | ICAO1 |
| 98 | WTFF | WAINWRIGHT TRANSFER COMPANY OF FAYE | | | SCAC4 |
| 99 | WTFG | WHITE, F G CO INC | | | SCAC4 |
| 100 | WTFH | WARRIOR, THE SERVICE TRANSPORTATION | | | SCAC4 |
