| 1 | PREX | Pioneer Railroad Equipment Co. Ltd. | added 7/1994; eliminated 4/1997; 7/2000-7/2005 (not listed) | | NAKINA |
| 2 | PREX | REA Express, Inc. | added 1/1971; eliminated 4/1974 | | NAKINA |
| 3 | PREX | REA Express, owned and operated by Railway Express Agency, Inc. | eliminated 1/1971 | | NAKINA |
| 4 | PREX | Pacific Refining Co. | 7/1923 | | NAKINA |
| 5 | PREX | REA Express | added 10/1970 | | NAKINA |
| 6 | PREX | REA Express | added 10/70; eliminated 4/74 | | NRHS |
| 7 | PREX | Pioneer Railroad Equipment Co. Ltd. | added 7/94; eliminated 4/97; 7/2000 | | NRHS |
| 8 | PREX | *PACIFIC REFINING CO. | | | PWRC |
| 9 | PREX | *REA EXPRESS, INC. (RAILWAY EXPRESS AGENCY, INC.) | | | PWRC |
| 10 | PREX | +PIONEER RAILROAD EQUIPMENT CO., LTD. | | | PWRC |
| 11 | PREX | Pioneer Railroad Equipment | | | RSRV |
| 12 | PREX | PIONEER RAILROAD EQUIPMENT CO., LTD | | | SCAC4 |
| 13 | PREX | Peoria & Western Railway | | USA | TRAFFIC |