| 1 | IRC | Iran Asseman Airlines | IATA: EP, IATA Prefix: 815, Name changed to Iran Aseman Airlines | IR | AVCODES |
| 2 | IRC | Iran Aseman Airline | IATA: EP, Callsign: Aseman, IATA Prefix: 815, Name changed from Iran Asseman Airlines | IR | AVCODES |
| 3 | IRC | Iran Aseman Airlines | IATA: EP | | ICAO1 |
| 4 | IRC | Intercolonial Ry. of Canada (Canadian National Rys.) | 8/1920-7/1932 | | NAKINA |
| 5 | IRC | Canadian Government Rys. (Canadian National Rys.) | 8/1920-7/1932 | | NAKINA |
| 6 | IRC | Canadian Government Rys. (Canadian National Rys.) | 23-Jul | | NRHS |
| 7 | IRC | CANADIAN NATIONAL RWY. [INTERCOLONIAL RWY. OF CANADA] | | | PWRC |
| 8 | IRC | InterRegional Calatori | | RO | TRAFFIC |
| 9 | IRCC | INDIAN RIVER CONSTRUCTION CO | | | PWRC |
| 10 | IRCH | INTERNATIONAL PAPER (LAFAYETTE CONT | | | SCAC4 |
| 11 | IRCL | INDUSTRIAL RESIN RECYCLING INC | | | SCAC4 |
| 12 | IRCN | IROC TRANSPORT INC | | | SCAC4 |
| 13 | IRCU | INTRUSCO LLC | | RUS | BIC |
| 14 | IRCU | KRONOS SA | | | SCAC4 |
| 15 | IRCX | Island Creek Corp. | eliminated 7/1997 | | NAKINA |
| 16 | IRCX | Nationwide Railroad Leasing, Inc. | added 4/1966; 10/1966-4/1970; eliminated 1/1971 | | NAKINA |
| 17 | IRCX | Morrison Plan, Inc. | added 1/1962; 7/1965; eliminated 4/1966 | | NAKINA |
| 18 | IRCX | International Railway Car Leasing Co. | added 1/1959; 4/1961; eliminated 1/1962 | | NAKINA |
| 19 | IRCX | International Railway Car Co. | added 10/1954; 10/1957; eliminated 1/1959 | | NAKINA |
| 20 | IRCX | International Railway Car & Equipment Co. | 1/1945-7/1954 (not listed) | | NAKINA |
| 21 | IRCX | Indian Refining Co., Inc. | 8/1920-7/1932 | | NAKINA |
| 22 | IRCX | International Railway Car & Equipment Co. | Jan-52 | | NRHS |
| 23 | IRCX | International Railway Car Co. | 10/57; eliminated 1/59 | | NRHS |
| 24 | IRCX | International Railway Car Leasing Co. | added 1/59; 4/61; eliminated 1/62 | | NRHS |
| 25 | IRCX | Morrison Plan, Inc. | added 1/62; 7/65; eliminated 4/66 | | NRHS |
| 26 | IRCX | Nationwide Railroad Leasing, Inc. | added 4/66; 10/66-4/70; eliminated 1/71 | | NRHS |
| 27 | IRCX | Island Creek Corp. | eliminated 7/97 | | NRHS |
| 28 | IRCX | *INDIAN REFINING CO., INC. | | | PWRC |
| 29 | IRCX | *NATIONWIDE RAILROAD LEASING, INC. [MORRISON PLAN, INC.; INTERNATIONAL RAILWAY CAR LEASING CO.] | | | PWRC |
| 30 | IRCX | *RETIRED 08-15-91 ATP (0359) | | | PWRC |
| 31 | IRCX | *ISLAND CREEK CORP. | | | PWRC |
| 32 | IRCZ | ITEL RAIL CORPORATION | | | PWRC |
