| 1 | EFR | Elf Air Ltd. | Callsign: Elfair, IATA Prefix: 934, Name changed to Grizoldubova Air | RUS | AVCODES |
| 2 | EFR | Erfoto | Callsign: Erfoto, | P | AVCODES |
| 3 | EFR | Eisenbahnfreunde Rodachtalbahn e.V | | DE | VKM |
| 4 | EFRA | EFRA SERVICE & ASSOCIATION CORP | | | SCAC4 |
| 5 | EFRI | Emile Frisch | | L | TRAFFIC |
| 6 | EFRL | ELITE FREIGHT LINES | | | SCAC4 |
| 7 | EFRN | Freunde der 212 001-2 e.V | | DE | VKM |
| 8 | EFRR | Effingham R.R. Co. | 7/2000-7/2005 | | NAKINA |
| 9 | EFRR | Effingham R.R. Co. | Jul-00 | | NRHS |
| 10 | EFRR | EFFINGHAM RAILROAD COMPANY | | | PWRC |
| 11 | EFRR | Effingham Railroad | | | RSRV |
| 12 | EFRR | EFFINGHAM RAILROAD COMPANY | | | SCAC4 |
| 13 | EFRT | ELITE FREIGHT | | | SCAC3 |
| 14 | EFRV | Euro Ferroviaria | | IT | VKM |
| 15 | EFRX | The Rail-Trailer Co. | added 7/1960; 4/1961; eliminated 1/1962 | | NAKINA |
| 16 | EFRX | The Rail-Trailer Co. | added 7/60; 4/61; eliminated 1/62 | | NRHS |
| 17 | EFRX | THE RAIL-TRAILER CO. | | | PWRC |
