| 1 | WSL | Westflight Aviation | | | ICAO1 |
| 2 | WSLB | WILSON LUBRICANTS | | | SCAC4 |
| 3 | WSLD | WEEMS & SON LLC | | | SCAC4 |
| 4 | WSLH | WUHL- SHAFMAN LIEBERMAN CORP | | | SCAC4 |
| 5 | WSLK | WATSON, LESLIE K | | | SCAC4 |
| 6 | WSLL | WALKING STICK LONG HAUL LLC | | | SCAC4 |
| 7 | WSLO | WESTCO LOGISTICS | | | SCAC4 |
| 8 | WSLQ | WALTERS & SONS LLC | | | SCAC4 |
| 9 | WSLS | WESTWIND SHIPPING AND LOGISTICS INC | | | SCAC4 |
| 10 | WSLT | WINSYS LOGISTICS INC | | | SCAC4 |
| 11 | WSLU | WESTWOOD SHIPPING LINES | | USA | BIC |
| 12 | WSLU | Westwood Shipping Lines | | | RSRV |
| 13 | WSLU | WESTWOOD SHIPPING LINES | | | SCAC4 |
| 14 | WSLX | Wheeling Steel Corp. | 7/1930-4/1961; eliminated 1/1965 | | NAKINA |
| 15 | WSLX | Wheeling Steel Corp. | 4/38-4/61; eliminated 1/65 | | NRHS |
| 16 | WSLX | WHEELING STEEL CORP. | | | PWRC |
| 17 | WSLZ | WILEY SANDERS TRUCK LINES, INC. | | | PWRC |
| 18 | WSLZ | Wiley Sanders Truck Lines | | | RSRV |
| 19 | WSLZ | WILEY SANDERS TRUCK LINES, INC. | | | SCAC4 |
