| 1 | WPR | Auckland Regional Rescue Helicopter Trust | Callsign: Westpac Rescue, | NZ | AVCODES |
| 2 | WPR | Auckland Regional Rescue Helicopter Trust | | | ICAO1 |
| 3 | WPRB | Western Pacific R.R. Co. | 7/1965-4/1970 | | NAKINA |
| 4 | WPRB | Western Pacific R.R. Co. | 7/65-4/70 | | NRHS |
| 5 | WPRB | WESTERN PACIFIC RAILROAD CO. | | | PWRC |
| 6 | WPRC | WELL PORT CONTAINER LINE INC | | | SCAC4 |
| 7 | WPRD | WOODWELL PRODUCTS | | | SCAC4 |
| 8 | WPRP | W P RAULS | | | SCAC4 |
| 9 | WPRR | Willamette & Pacific R.R., Inc. | added 7/1993; 1/1994-7/2005 | | NAKINA |
| 10 | WPRR | Willamette & Pacific R.R., Inc. | added 7/93; 1/94-7/2000 | | NRHS |
| 11 | WPRR | WILLAMETTE & PACIFIC RAILROAD COMPANY, INC. | | | PWRC |
| 12 | WPRR | Willamette and Pacific Railroad | | | RSRV |
| 13 | WPRR | WILLAMETTE & PACIFIC RAILROAD INC | | | SCAC4 |
| 14 | WPRR | Willamette & Pacific | | USA | TRAFFIC |
| 15 | WPRU | WATERMAN OF PUERTO RICO-USA INC | | | PWRC |
| 16 | WPRU | Waterman of Puerto Rico-USA | | | RSRV |
| 17 | WPRX | Wainwright Producers and Refiners Ltd. | added 4/1956; 10/1957-4/1961; eliminated 4/1962 | | NAKINA |
| 18 | WPRX | Union Tank Car Co. | added 4/1962; eliminated 10/1962 | | NAKINA |
| 19 | WPRX | Fruit Growers Express Co. | added 7/1968; 4/1970-1/1975; eliminated 7/1978 | | NAKINA |
| 20 | WPRX | Wainwright Producers and Refiners Ltd. | 10/57-4/61; eliminated 4/62 | | NRHS |
| 21 | WPRX | Union Tank Car Co. | added 4/62 | | NRHS |
| 22 | WPRX | Fruit Growers Express Co. | added 7/68; 4/70-1/75; eliminated 7/78 | | NRHS |
| 23 | WPRX | *WAINWRIGHT PRODUCERS & REFINERS LTD. | | | PWRC |
| 24 | WPRX | *FRUIT GROWERS EXPRESS CO. [UNION TANK CAR CO.] | | | PWRC |
| 25 | WPRX | *WESTPORT RAILWAY CORPORATION FOUNDATION | | | PWRC |
