| 1 | WD | WDL Aviation GmbH & Co. KG | ICAO: WDL, Callsign: WDL, Designator WD recalled by IATA. | D | AVCODES |
| 2 | WD | Wardair Canada Ltd. | ICAO: WDA, Callsign: Wardair, Merged into Canadian Airlines 15 January 1990. | CDN | AVCODES |
| 3 | WD | DAS Air Limited | ICAO: DAZ, Callsign: Dasair, IATA Prefix: 761, Name changed to Dairo Air Service Ltd. IATA code changed from SE* | EAK | AVCODES |
| 4 | WD | Dairo air Service Ltd. | ICAO: DSR, Callsign: Dasair, IATA Prefix: 761, Name changed from DAS Air Limited. IATA code changed from SE* | EAK | AVCODES |
| 5 | WD | Amsterdam Airlines BV | ICAO: AAN, Callsign: Amstel, Founded in 2007. Ceased operations on 31 October 2011. | NL | AVCODES |
| 6 | WD | Wat Phnom Airlines | ICAO: WPH, Callsign: Wat Phnom, IATA Prefix: 913, Ceased operations during 2014. | K | AVCODES |
| 7 | WD | Modern Transporte Aereo De Carga S.A. d/b/a Modern Logistics | ICAO: MWM, Callsign: Modernair, IATA Prefix: 372, | BR | AVCODES |
| 8 | WD | LLC Aviation Company Eleron | ICAO: VVA, Callsign: Load Shark, IATA Prefix: 352, | UA | AVCODES |
| 9 | WD | Kleinbahn Wedenau - Deutz | | D | TRAFFIC |
| 10 | WDA | Wardair Canada Ltd. | IATA: WD, Callsign: Wardair, Merged into Canadian Airlines 15 January 1990. | CDN | AVCODES |
| 11 | WDA | Wimbi Dira Airways | IATA: 9C, Callsign: Wimbidira, Designator 9C* recalled by IATA. Accounting code 357 recalled by IATA. Founded in 2003. Operations commenced on 13 August 2003. | ZRE | AVCODES |
| 12 | WDA | Adam Aircraft Services GmbH | Callsign: Adam, | RSM | AVCODES |
| 13 | WDA | Wimbi Dira Airways | | | ICAO1 |
| 14 | WDAE | WOODALL ENTERPRISES INC | | | SCAC4 |
| 15 | WDAI | WAYNES DELIVERY | | | SCAC4 |
| 16 | WDAS | WALTS DRIVE-A-WAY SERVICE INC | | | SCAC4 |
| 17 | WDAX | Washington Dept. of Agriculture | 1/1994-7/2005 (not listed) | | NAKINA |
| 18 | WDAX | Washington Dept. of Agriculture | Jul-00 | | NRHS |
| 19 | WDAX | Washington Dept. of Agriculture | Jan-94 | | NRHS |
| 20 | WDAX | WASHINGTON DEPARTMENT OF AGRICULTURE | | | PWRC |
| 21 | WDAX | Washington Department of Agriculture | | | RSRV |
| 22 | WDAX | WASHINGTON DEPARTMENT OF AGRICULTUR | | | SCAC4 |
| 23 | WDBC | WOODBURY TRANSPORTATION INC | | | SCAC4 |
| 24 | WDBI | WDS BROKERAGE INC | | | SCAC4 |
| 25 | WDBP | WIDDICOMB TRANSPORT INC | | | SCAC4 |
| 26 | WDBT | WOODARD DISTRIBUTING LLC | | | SCAC4 |
| 27 | WDC | Washington Metropolitan Area Transit Authority | City: Washington DC | US-DC | TRAFFIC |
| 28 | WDCC | WEBSTER, DON COMPANY INC, THE | | | SCAC4 |
| 29 | WDCH | WOOD, CHAS & SON MOVING INC | | | SCAC4 |
| 30 | WDCM | WOOD FARMS | | | SCAC4 |
| 31 | WDCN | WARD DISTRIBUTING COMPANY INC | | | SCAC4 |
| 32 | WDCP | WAYNE-DALTON CORP | | | SCAC4 |
| 33 | WDCQ | WORLDWIDE CONTAINER TRANSPORT INC | | | SCAC4 |
| 34 | WDCX | Wm. Davies Co., Inc. | 8/1920-7/1932 | | NAKINA |
| 35 | WDCX | Wm. Davies Co., Inc. (Canada Packers Ltd.) | 7/1935 | | NAKINA |
| 36 | WDCX | Warren-Douglas Chemical Co., Inc. | added 10/1964; 7/1965-4/1970; eliminated 11/1973 | | NAKINA |
| 37 | WDCX | Warren-Douglas Chemical Co., Inc. | Apr-70 | | NRHS |
| 38 | WDCX | Warren-Douglas Chemical Co., Inc. | 7/65-10/66; eliminated 11/73 | | NRHS |
| 39 | WDCX | *WM. DAVIES CO., INC. | | | PWRC |
| 40 | WDCX | *WARREN-DOUGLAS CHEMICAL CO., INC. | | | PWRC |
| 41 | WDCY | WORLDWIDE DELIVERY CORP | | | SCAC4 |
| 42 | WDDA | WOOD, DAVID TRUCKING | | | SCAC4 |
| 43 | WDDB | WESTERN DISPATCH & DISTRIBUTION | | | SCAC4 |
| 44 | WDDL | WADDELL TRANSFER INC | | | SCAC4 |
| 45 | WDDN | WADDEN TRANSPORTATION INC | | | SCAC4 |
| 46 | WDDT | WELDED TUBE OF CANADA | | | SCAC4 |
| 47 | WDE | Pallas Aviation, LLC | Callsign: Sandstone, | USA | AVCODES |
| 48 | WDEA | WADE TRANSPORTATION COMPANY INC | | | SCAC4 |
| 49 | WDEG | WRIGLEY DESIGNS | | | SCAC4 |
| 50 | WDEP | WINDERMERE PROPERTIES LLC | | | SCAC4 |
| 51 | WDFC | W D F INC | | | SCAC4 |
| 52 | WDFE | WOODFIELD INC | | | SCAC4 |
| 53 | WDFG | WOODSON FREIGHT | | | SCAC4 |
| 54 | WDFN | WOODFIN OIL CO | | | SCAC4 |
| 55 | WDFO | WE DO FOR YOU | | | SCAC4 |
| 56 | WDFR | WIND AFRAMAX TANKER CORPORATION | | | SCAC4 |
| 57 | WDFU | ALLNEX AUSTRIA GMBH | | A | BIC |
| 58 | WDG | Ministry Of Agriculture Fisheries And Food | Callsign: Watchdog, | GB | AVCODES |
| 59 | WDG | Ministry of Agriculture, Fisheries and Food | | | ICAO1 |
| 60 | WDGP | WIDE DISTRIBUTION GROUP INC | | | SCAC4 |
| 61 | WDHC | WAMBOLD, HOWARD C | | | SCAC4 |
| 62 | WDHG | WINDISH TRUCKING INC | | | SCAC4 |
| 63 | WDHT | WDH TRUCKING INC | | | SCAC4 |
| 64 | WDHU | TSIDEHAAN GMBH | | D | BIC |
| 65 | WDIN | WEST, DEAN, TRUCKING, INC | | | SCAC1 |
| 66 | WDIN | WEST, DEAN TRUCKING INC | | | SCAC4 |
| 67 | WDIU | WHEELS DEDICATED INC | | | SCAC4 |
| 68 | WDIV | WILSON DIVERSIFIED SERVICES | | | SCAC4 |
| 69 | WDJC | WHELAN, D J & CO INC | | | SCAC4 |
| 70 | WDJM | WOODS, JIM MARKETING INC | | | SCAC4 |
| 71 | WDJT | WOOD, JIMMY T INC | | | SCAC4 |
| 72 | WDK | Oxford Air Services Ltd. | Callsign: Woodstock, Name changed to Capital Air Services Ltd. | GB | AVCODES |
| 73 | WDK | Capital Air Services Ltd. | Callsign: Woodstock, Name changed from Oxford Air Services Ltd. | GB | AVCODES |
| 74 | WDK | Oxford Air Services | | | ICAO1 |
| 75 | WDKC | WOOD TRUCKING CORPORATION | | | SCAC4 |
| 76 | WDKG | WENDT TRUCKING | | | SCAC4 |
| 77 | WDKI | WEILAND TRUCKING COMPANY INC | | | SCAC4 |
| 78 | WDL | WDL Aviation GmbH & Co. KG | IATA: WD, Callsign: WDL, Designator WD recalled by IATA. | D | AVCODES |
| 79 | WDL | WDL Aviation GmbH & Co. KG | IATA: WH, Callsign: WDL, IATA Prefix: 944, Name changed to German Airways. ICAO designator changed to GER. Designator WD recalled by IATA. | D | AVCODES |
| 80 | WDL | WDL Aviation | IATA: W1 | | ICAO1 |
| 81 | WDLC | WATERDALE INC | | | SCAC4 |
| 82 | WDLH | WADLEIGHS INC | | | SCAC4 |
| 83 | WDLL | WD LOGISTICS L L C | | | SCAC4 |
| 84 | WDLM | WILLY DOG LTD | | | SCAC4 |
| 85 | WDLO | WORLD OIL TOOLS INC | | | SCAC4 |
| 86 | WDLQ | WHITE DUCKS LTD | | | SCAC4 |
| 87 | WDLR | WENDLAND TRUCKING | | | SCAC1 |
| 88 | WDLS | WORLD LOGISTICS SERVICE (USA) INC. | | | SCAC1 |
| 89 | WDLS | WORLD LOGISTICS SERVICE (USA) INC | | | SCAC4 |
| 90 | WDLT | WORLD LINK TRANSPORTATION | | | SCAC4 |
| 91 | WDLX | Waddell Coal Mining Co., Inc. | 1/1952-10/1957; eliminated 4/1958 | | NAKINA |
| 92 | WDLX | Waddell Coal Mining Co., Inc. | 1/52-10/57 | | NRHS |
| 93 | WDLX | WADDELL COAL MINING CO., INC. | | | PWRC |
| 94 | WDLY | WOODIWISS LOG & TIMBER SYSTEMS INC | | | SCAC4 |
| 95 | WDMA | WIEDMAIER TRUCKS STOP | | | SCAC4 |
| 96 | WDMG | WAREHOUSE DISTRIBUTION MANAGEMENT | | | SCAC4 |
| 97 | WDMK | WESTERDALE, D & M TRUCKING INC | | | SCAC4 |
| 98 | WDML | WESTWOOD MFG LTD | | | SCAC4 |
| 99 | WDMR | WOODS, MARK | | | SCAC1 |
| 100 | WDMZ | WEST DECKER MINE | | | PWRC |
