| 601 | WBSH | WORLDBRIDGE SHIPPING INC | | | SCAC4 |
| 602 | WBSI | WEBSCAN INC | | | SCAC4 |
| 603 | WBSK | WILSON BROS TRUCKING | | | SCAC4 |
| 604 | WBSL | WEBCO SERVICES LLC | | | SCAC4 |
| 605 | WBSO | WAYNE BUILT & SON INC | | | SCAC4 |
| 606 | WBSQ | WBS INC | | | SCAC4 |
| 607 | WBST | WINDHAM BUTCHER SHOP TRUCKING INC | | | SCAC4 |
| 608 | WBSV | WILLMAR BUS SERVICE | | | SCAC4 |
| 609 | WBSW | WHITE, BOB SALES | | | SCAC4 |
| 610 | WBSW | White Bus Service of Windfield | | GB | TRAFFIC |
| 611 | WBSZ | WILBANKS STEEL COMPANY | | | PWRC |
| 612 | WBT | Weets Bahntransport GmbH | Emden | D | privat-bahn.de |
| 613 | WBT | WHITE & BLUE TAXI OF | | | SCAC4 |
| 614 | WBTC | WILSON, BILL TRUCKING LLC | | | SCAC4 |
| 615 | WBTC | Wabtec Rail Limited | | GB | TRAFFIC |
| 616 | WBTE | WEST BROTHERS TRANSFER & STORAGE H&S DIV | | | SCAC1 |
| 617 | WBTF | WOOD BAY TURF TECHNOLOGIES | | | SCAC4 |
| 618 | WBTG | WILSON, BARRY TRUCKING | | | SCAC4 |
| 619 | WBTI | WESTBROOK TECHNOLOGIES INC | | | SCAC4 |
| 620 | WBTK | WILLIAMS BROTHERS TRUCKING LLC | | | SCAC4 |
| 621 | WBTL | WIEBE BROS TRANSPORTATION LTD | | | SCAC4 |
| 622 | WBTR | WHELAN BROTHERS TRANSPORT | | | SCAC4 |
| 623 | WBTS | Waco, Beaumont, Trinity & Sabine Ry. Co. | 1/1975-7/2005 | | NAKINA |
| 624 | WBTS | Waco, Beaumont, Trinity & Sabine Ry. Co. | 1/75-7/2000 | | NRHS |
| 625 | WBTS | WACO, BEAUMONT, TRINITY & SABINE RWY | | | PWRC |
| 626 | WBTS | Waco, Beaumont, Trinity and Sabine Railway | | | RSRV |
| 627 | WBTT | WTI TRANSPORT INC | | | SCAC4 |
| 628 | WBTU | WILBERT TRADING BV | | NL | BIC |
| 629 | WBTU | WILBERT TRADING BV | | | SCAC4 |
| 630 | WBTV | WOODMAN, BOB TIRES INC | | | SCAC4 |
| 631 | WBTW | WEST BROTHERS TRUCKING INC | | | SCAC4 |
| 632 | WBUL | WESTCAN BULK TRANSPORT LTD | | | SCAC4 |
| 633 | WBUO | WATERBUOY PUMPS | | | SCAC4 |
| 634 | WBUR | WILBURN OIL CO INC | | | SCAC4 |
| 635 | WBUS | Westfalen Bus GmbH | Real: WB | D | TRAFFIC |
| 636 | WBVS | WILLOW BEE VENTURES | | | SCAC4 |
| 637 | WBWC | WRIGHT, BARRY W CONSTRUCTION CO INC | | | SCAC4 |
| 638 | WBWP | WILSON, B W PAPER CO INC | | | SCAC4 |
| 639 | WBXI | WINNSBORO TRANSPORT INC | | | SCAC4 |
| 640 | WBXN | WBT TRANSPORTATION | | | SCAC4 |
| 641 | WBXU | WILLBOX LTD | | GB | BIC |
| 642 | WBYT | WILD BOYZ TRANSPORT LTD | | | SCAC4 |
| 643 | WBZ | WHEELER BROTHERS GRAIN CO. | | | PWRC |
| 644 | WC | Wien Consolidated Airlines Ltd. | Callsign: Wien Consolidated, | USA | AVCODES |
| 645 | WC | Islena de Inversiones S.A. de C.V. d/b/a Islena Airlines | ICAO: ISV, IATA Prefix: 506, Designator WC reinstated by IATA. Founded in 1981. Name changed to Avianca Honduras. | HN | AVCODES |
| 646 | WC | Avianca Honduras | ICAO: ISV, IATA Prefix: 506, Designator WC reinstated by IATA. Founded in 1981. Name changed from Islena de Inversiones S.A. de C.V. d/b/a Islena Airlines | HN | AVCODES |
| 647 | WC | Wisconsin Central Ltd. | added 1/1988; 1/1994-7/2005 | | NAKINA |
| 648 | WC | Wisconsin Central Ltd. | added 1/88; 1/94-7/2000 | | NRHS |
| 649 | WC | CANADIAN NATIONAL RWY. [WISCONSIN CENTRAL RWY.] | | | PWRC |
| 650 | WC | Wisconsin Central Railway (Canadian National Railway) | | | RSRV |
| 651 | WC | WISCONSIN CENTRAL LIMITED | | | SCAC4 |
| 652 | WC | Wisconsin Central Limited | | USA | TRAFFIC |
| 653 | WCA | West Coast Airways Limited | Callsign: West-Leone, | WAL | AVCODES |
| 654 | WCA | West Coast Airways | | | ICAO1 |
| 655 | WCAA | WILLINGHAM CANADA | | | SCAC4 |
| 656 | WCAC | WESTWAY GROUP CANADA INC | | | SCAC4 |
| 657 | WCAF | WINDY CITY CARRIERS INC | | | SCAC4 |
| 658 | WCAI | WCA LOGISTICS LLC | | | SCAC4 |
| 659 | WCAL | WEST COAST AMUSEMENT LTD | | | SCAC4 |
| 660 | WCAM | WOOD CARRIERS INC | | | SCAC4 |
| 661 | WCAP | WILDCAT TRANSPORT SERVICE | | | SCAC4 |
| 662 | WCAQ | WEST CENTRAL AG SERVICES INC | | | SCAC4 |
| 663 | WCAR | WHITACRE, CARROLL E | | | SCAC4 |
| 664 | WCAU | WORLD CONTAINER TRADING GMBH | | | SCAC4 |
| 665 | WCAW | WHITBY TRUCKING | | | SCAC4 |
| 666 | WCAX | Westcan Rail Ltd. | 7/2000-7/2005 (not listed) | | NAKINA |
| 667 | WCAX | Westcan Rail Ltd. | Jul-00 | | NRHS |
| 668 | WCAX | WESTCAN RAIL LTD. | | | PWRC |
| 669 | WCAX | Westcan Rail Limited | | | RSRV |
| 670 | WCAX | WESTCAN RAIL LTD | | | SCAC4 |
| 671 | WCB | West Africa Airlines Ltd. | IATA: WH, Callsign: Kilo Yankee, Ceased operations. | GH | AVCODES |
| 672 | WCB | West Africa Airlines | | | ICAO1 |
| 673 | WCB | Wagon Care | | NL | TRAFFIC |
| 674 | WCB | Wagon Care B.V. | | NL | VKM |
| 675 | WCBD | WEST COAST T & D INC | | | SCAC4 |
| 676 | WCBM | WORTHINGTON COMPANY, THE | | | SCAC4 |
| 677 | WCBQ | WCB TRUCKING INC | | | SCAC4 |
| 678 | WCBR | WOODCOCK BROTHERS | | | SCAC4 |
| 679 | WCBS | WE COVER BUILDINGS | | | SCAC4 |
| 680 | WCBT | WORLD COURIER GROUND | | | SCAC4 |
| 681 | WCBY | WALLACE, BEVERLY L | | | SCAC4 |
| 682 | WCC | Sports Air Travel, Inc. | Callsign: West Coast, | USA | AVCODES |
| 683 | WCC | West Coast Aviation Services, LLC / West Coast Charters | Callsign: West Coast, | USA | AVCODES |
| 684 | WCC | Sport Air Travel | | | ICAO1 |
| 685 | WCCA | WEST COAST CARRIERS INC | | | SCAC4 |
| 686 | WCCB | WEST COAST CABINETRY (2002) LTD | | | SCAC4 |
| 687 | WCCD | WEST COAST CONTAINER SERVICES INC | | | SCAC4 |
| 688 | WCCE | WESTERN CONTAINER CARRIER INC | | | SCAC4 |
| 689 | WCCJ | WEST COAST TRANSPORT LINES INC | | | SCAC4 |
| 690 | WCCL | Wisconsin Chicago Link Ltd. | added 4/2000; 7/2000-7/2005 | | NAKINA |
| 691 | WCCL | Wisconsin Chicago Link Ltd. | added 4/2000; 7/2000 | | NRHS |
| 692 | WCCL | CANADIAN NATIONAL RWY. [WISCONSIN CHICAGO LINK LTD.; WISCONSIN CENTRAL RWY.] | | | PWRC |
| 693 | WCCL | Wisconsin Central Railway (Canadian National Railway) | | | RSRV |
| 694 | WCCL | WISCONSIN CHICAGO LINK LTD | | | SCAC4 |
| 695 | WCCL | Wisconsin Chicago Link Ltd. | | USA | TRAFFIC |
| 696 | WCCM | WEST COAST COMMODITIES INC | | | SCAC4 |
| 697 | WCCN | WIREGRASS CONSTRUCTION CO INC | | | SCAC4 |
| 698 | WCCO | WESTCOAST CONVERTERS | | | SCAC4 |
| 699 | WCCP | WILLIAM CARTER COMPANY, THE | | | SCAC4 |
| 700 | WCCQ | WHEAT CITY CONCRETE | | | SCAC4 |
