| 3601 | WPRX | Union Tank Car Co. | added 4/1962; eliminated 10/1962 | | NAKINA |
| 3602 | WPRX | Fruit Growers Express Co. | added 7/1968; 4/1970-1/1975; eliminated 7/1978 | | NAKINA |
| 3603 | WPRX | Wainwright Producers and Refiners Ltd. | 10/57-4/61; eliminated 4/62 | | NRHS |
| 3604 | WPRX | Union Tank Car Co. | added 4/62 | | NRHS |
| 3605 | WPRX | Fruit Growers Express Co. | added 7/68; 4/70-1/75; eliminated 7/78 | | NRHS |
| 3606 | WPRX | *WAINWRIGHT PRODUCERS & REFINERS LTD. | | | PWRC |
| 3607 | WPRX | *FRUIT GROWERS EXPRESS CO. [UNION TANK CAR CO.] | | | PWRC |
| 3608 | WPRX | *WESTPORT RAILWAY CORPORATION FOUNDATION | | | PWRC |
| 3609 | WPS | WHEELING PITTSBURGH STEEL | | | PWRC |
| 3610 | WPSI | WILSON PET SUPPLY INC | | | SCAC4 |
| 3611 | WPSK | WAGRAM PAPER STOCK INC | | | SCAC4 |
| 3612 | WPSMU | Wytwórnia Podkładów Strunobetonowych S.A. | | PL | VKM |
| 3613 | WPST | WPS TEAM LOGISTICS, INC. | | | SCAC4 |
| 3614 | WPSU | ALASKA STRUCTURES INC | | USA | BIC |
| 3615 | WPSX | W.P. Stork Refrigerator Line | 7/1930-7/1932 | | NAKINA |
| 3616 | WPSX | Wisconsin Public Service Corp. | added 10/1981; eliminated 4/1993; 1/1994-7/2005 (not listed) | | NAKINA |
| 3617 | WPSX | Wisconsin Public Service Corp. | added 10/81; eliminated 4/93; 1/94-7/2000 | | NRHS |
| 3618 | WPSX | *W. P. STORK REFRIGERATOR LINE | | | PWRC |
| 3619 | WPSX | *WESTERN PLANT SERVICES (CALIFORNIA) | | | PWRC |
| 3620 | WPSX | +WISCONSIN PUBLIC SERVICE CORPORATION | | | PWRC |
| 3621 | WPSX | Wisconsin Public Service Corporation | | | RSRV |
| 3622 | WPSX | WISCONSIN PUBLIC SERVICE CORPORATIO | | | SCAC4 |
| 3623 | WPT | Wapiti Aviation Ltd. | Callsign: Wapiti, | CDN | AVCODES |
| 3624 | WPT | World 2 Fly Portugal, S.A. | IATA: 3P, Callsign: New Blue, | P | AVCODES |
| 3625 | WPT | Wapiti Aviation | | | ICAO1 |
| 3626 | WPT | The Wabash-Pittsburgh Terminal Ry. (The Pittsburgh & West Virginia Ry. Co.) | 8/1920-7/1930 | | NAKINA |
| 3627 | WPT | The Pittsburgh & West Virginia Ry. Co. | 7/1932 | | NAKINA |
| 3628 | WPT | PITTSBURGH & WEST VIRGINIA RWY. CO. {WABASH-PITTSBURGH TERMINAL RWY.] | | | PWRC |
| 3629 | WPT | WEST POINT TOURS INC | | | SCAC4 |
| 3630 | WPTA | WESTERN PACIFIC TRANSPORT LTD | | | SCAC4 |
| 3631 | WPTD | WP TRANSPORTATION INC | | | SCAC4 |
| 3632 | WPTE | WESTERN PACIFIC TRANSPORT LLC | | | SCAC4 |
| 3633 | WPTK | WHISPERING PINES TRUCKING INC | | | SCAC4 |
| 3634 | WPTL | WALKER, P & T CAPITAL LTD | | | SCAC4 |
| 3635 | WPTN | WALLPORT TRANSIT XPRESS INC | | | SCAC4 |
| 3636 | WPTQ | WESTPOINT TRANSPORTATION INC | | | SCAC4 |
| 3637 | WPTT | WESTERN PORTS TRANSPORTATION INC | | | SCAC4 |
| 3638 | WPTZ | UNION PACIFIC RAILROAD COMPANY | | | PWRC |
| 3639 | WPTZ | Western Pacific Railroad (Union Pacific Railroad) | | | RSRV |
| 3640 | WPTZ | UNION PACIFIC RAILROAD COMPANY | | | SCAC4 |
| 3641 | WPWP | W P WESTERN PACIFIC FREIGHT SYSTEMS | | | SCAC4 |
| 3642 | WPWX | Wilson Propane Wholesale Co., Inc. | added 10/1976; eliminated 10/1977 | | NAKINA |
| 3643 | WPWX | Wilson Propane Wholesale Co. | added 10/1977; 1/1980; eliminated 7/1981 | | NAKINA |
| 3644 | WPWX | Fruit Growers Express Co. | added 7/1981; eliminated 4/1982 | | NAKINA |
| 3645 | WPWX | Wilson Propane Wholesale Co. | 1/80; eliminated 7/81 | | NRHS |
| 3646 | WPWX | Fruit Growers Express Co. | added 7/81; eliminated 4/82 | | NRHS |
| 3647 | WPWX | WILSON PROPANE WHOLESALE CO., INC. (FRUIT GROWERS EXPRESS CO.) | | | PWRC |
| 3648 | WPX | Wood Products Co. | 8/1920-7/1923 | | NAKINA |
| 3649 | WPX | WOOD PRODUCTS CO. | | | PWRC |
| 3650 | WPXC | WPX COURIERS | | | SCAC4 |
| 3651 | WPXI | WHITE PLUS XPRESS INC | | | SCAC4 |
| 3652 | WPXY | WORLDPOINT TRANSPORT COMPANY | | | SCAC4 |
| 3653 | WPXZ | UNION PACIFIC RAILROAD COMPANY | | | PWRC |
| 3654 | WPXZ | Western Pacific Railroad (Union Pacific Railroad) | | | RSRV |
| 3655 | WPXZ | UNION PACIFIC RAILROAD COMPANY | | | SCAC4 |
| 3656 | WPY | White Pass & Yukon Route | 1/1975-1/1980 | | NAKINA |
| 3657 | WPY | White Pass & Yukon Corp., Ltd. | 7/2005 | | NAKINA |
| 3658 | WPY | White Pass & Yukon Route | 1/75-1/80 | | NRHS |
| 3659 | WPY | WHITE PASS & YUKON CORPORATION, LTD. | | | PWRC |
| 3660 | WPY | White Pass and Yukon Route | | | RSRV |
| 3661 | WPY | WHITE PASS & YUKON | | | SCAC4 |
| 3662 | WPZ | *UNION PACIFIC RAILROAD COMPANY | | | PWRC |
| 3663 | WPZ | *WESTERN PAVING | | | PWRC |
| 3664 | WPZ | Western Pacific Railroad (Union Pacific Railroad) | | | RSRV |
| 3665 | WPZ | UNION PACIFIC RAILROAD COMPANY | | | SCAC4 |
| 3666 | WPZA | WHAT A PIZZA | | | SCAC4 |
| 3667 | WQ | Romanian Aviation Company ROMAVIA R.A. | ICAO: RMV, Callsign: Aeromavia, IATA Prefix: 534, Designator WQ reinstated by IATA. Declared bankrupt and ceased operations in August 2014. | RO | AVCODES |
| 3668 | WQ | Bahamas World Airlines (1974) Ltd. | ICAO: WQA, Callsign: Whiskey Quebec, | BS | AVCODES |
| 3669 | WQ | Interstate Equipment Leasing, Inc. d/b/a Swift Air | ICAO: SWQ, Callsign: Swiftflight, IATA designator changed from Q7. | USA | AVCODES |
| 3670 | WQ | iAero Airways d/b/a Swift Air | ICAO: SWQ, Callsign: Swiftflight, Name changed from Interstate Equipment Leasing, Inc. d/b/a Swift Air. IATA designator changed from Q7. | USA | AVCODES |
| 3671 | WQA | Bahamas World Airlines (1974) Ltd. | IATA: WQ, Callsign: Whiskey Quebec, | BS | AVCODES |
| 3672 | WQAX | Warner-Quinlan Co. | 8/1920-7/1930 | | NAKINA |
| 3673 | WQAX | WARNER-QUINLAN CO. | | | PWRC |
| 3674 | WQGC | WINDSOR G | | | SCAC4 |
| 3675 | WQIN | WINDLE, W W | | | SCAC4 |
| 3676 | WQMI | WINNISQUAM MARINE INC | | | SCAC4 |
| 3677 | WQOC | WESTPHAL OIL CO | | | SCAC4 |
| 3678 | WQSS | WORLD SEAS SHIPPING LINE INC | | | SCAC4 |
| 3679 | WR | Royal Tongan Airlines | ICAO: HRH, Callsign: Tonga Royal, IATA Prefix: 971, Ceased operatioins | TO | AVCODES |
| 3680 | WR | Aviaprad, Joint-Stock Company | ICAO: VID, Callsign: Aviaprad, Founded in 1996. Ceased operations on 05 February 2008. | RUS | AVCODES |
| 3681 | WR | Westjet Encore Ltd. | ICAO: WEN, Callsign: Encore, Commenced operations on 24 June 2013. | CDN | AVCODES |
| 3682 | WR | Wincanton Rail GmbH | St. Ingbert | D | privat-bahn.de |
| 3683 | WR | WHIPPANY RIVER | | | PWRC |
| 3684 | WR | Westrail | | AUS | TRAFFIC |
| 3685 | WRA | White River Air Services Ltd. | | CDN | AVCODES |
| 3686 | WRA | White River Air Services | | | ICAO1 |
| 3687 | WRA | CSX TRANSPORTATION [SEABOARD SYSTEM; WESTERN RAILWAY OF ALABAMA] | | | PWRC |
| 3688 | WRA | Western Railway of Alabama (CSX Transportation) | | | RSRV |
| 3689 | WRA | Western Railway of Alabama | | USA | TRAFFIC |
| 3690 | WRAA | WILLIAMS, R A & SONS | | | SCAC4 |
| 3691 | WRAB | WESTGATE, RICHARD TRUCKING | | | SCAC4 |
| 3692 | WRAC | WRIGHT, A C TRUCKING INC | | | SCAC4 |
| 3693 | WRAE | WILLIAMS, R TRUCKING | | | SCAC4 |
| 3694 | WRAF | WRIGHTS RAINBOWS | | | SCAC4 |
| 3695 | WRAI | WESTAR INC | | | SCAC4 |
| 3696 | WRAJ | WEST, R A INTERNATIONAL INC | | | SCAC4 |
| 3697 | WRAK | WARACK TRUCKING | | | SCAC4 |
| 3698 | WRAM | WU, RAMON | | | SCAC4 |
| 3699 | WRAS | WRIGHT AIR SERVICE INC (AIR CODE 8V | | | SCAC4 |
| 3700 | WRAX | The Wine Railway Appliance Co. | 7/1930-1/1941 | | NAKINA |
