| 1 | WTL | Atlantic Flight Training Ltd. | Callsign: Whittle, Purchased by Airways Aviation. | GB | AVCODES |
| 2 | WTL | West Texas and Lubbock R.R. Co. Inc. | 7/2000-7/2005 | | NAKINA |
| 3 | WTL | West Texas and Lubbock R.R. Co. Inc. | Jul-00 | | NRHS |
| 4 | WTL | WEST TEXAS & LUBBOCK RAILROAD CO., INC. | | | PWRC |
| 5 | WTL | West Texas and Lubbock Railroad | | | RSRV |
| 6 | WTLA | WINTER TRUCK LINE | | | SCAC4 |
| 7 | WTLB | WETZEL, JOHN E | | | SCAC4 |
| 8 | WTLC | West Texas and Lubbock R.R. Co. | eliminated 1/2004 | | NAKINA |
| 9 | WTLC | West Texas and Lubbock Ry. Co. | 7/2005 | | NAKINA |
| 10 | WTLC | WEST TEXAS & LUBBOCK RAILROAD CO., INC. | | | PWRC |
| 11 | WTLC | West Texas and Lubbock Railroad | | | RSRV |
| 12 | WTLC | WEST TEXAS AND LUBBOCK RAILWAY COMP | | | SCAC4 |
| 13 | WTLI | WESWEN TRUCK LINES INC | | | SCAC4 |
| 14 | WTLJ | WHITE, L A TRUCKING CO INC | | | SCAC4 |
| 15 | WTLK | WAITE, LEITH K | | | SCAC4 |
| 16 | WTLM | WINDSPEAR TRANSPORTATION LTD | | | SCAC4 |
| 17 | WTLP | WOODLAND TRANSPORTATION LLC | | | SCAC4 |
| 18 | WTLQ | WESTERN TANKLINES | | | SCAC4 |
| 19 | WTLR | West Texas and Lubbock R.R. Co. Inc. | added 1/1996; eliminated 7/1999; 7/2000-7/2005 | | NAKINA |
| 20 | WTLR | West Texas and Lubbock R.R. Co. Inc. | added 1/96; eliminated 7/99; 7/2000 | | NRHS |
| 21 | WTLR | WEST TEXAS & LUBBOCK RAILROAD CO., INC. | | | PWRC |
| 22 | WTLR | West Texas and Lubbock Railroad | | | RSRV |
| 23 | WTLR | WEST TEXAS AND LUBBOCK RAILROAD COM | | | SCAC4 |
| 24 | WTLS | WELLS TRUCKING & LEASING INC | | | SCAC4 |
| 25 | WTLU | WHITE LINE SHIPPING | | UAE | BIC |
| 26 | WTLU | WHITE LINE SHIPPING | | | SCAC4 |
| 27 | WTLW | WILLMAX TRUCKING LLP | | | SCAC4 |
| 28 | WTLX | Washington Tank Car Co. | 8/1920 | | NAKINA |
| 29 | WTLX | White Tank Line | 7/1930-7/1932 | | NAKINA |
| 30 | WTLX | Western Tank Line | 4/1947-1/1950 | | NAKINA |
| 31 | WTLX | Wilmot Transportation & Logistics Ltd. | added 1/2004; 7/2005; eliminated 4/2007 | | NAKINA |
| 32 | WTLX | WT&L Corp. | added 4/2007 | | NAKINA |
| 33 | WTLX | *WASHINGTON TANK CAR CO. | | | PWRC |
| 34 | WTLX | *WHITE TANK LINE | | | PWRC |
| 35 | WTLX | *WESTERN TANK LINE | | | PWRC |
| 36 | WTLX | +WT&L CORP. [WILMOT TRANSPORTATION & LOGISTICS LTD.] | | | PWRC |
| 37 | WTLX | WILMOT TRANSPORTATION & LOGISTICS L | | | SCAC4 |
| 38 | WTLZ | WTL RAIL CORPORATION | | | PWRC |
| 39 | WTLZ | WTL Rail Corporation | | | RSRV |
| 40 | WTLZ | WTL RAIL CORPORATION | | | SCAC4 |
