| Abbreviation | Definition |
|---|---|
| EMPX | Empiregas Equipment Corporation |
| EMR | Ergonomic Modular Rail |
| EMRU | Equipment Management Services |
| EMRY | Eastern Maine Railway |
| EMRY | Eastern Maine Railway Company |
| EMSU | Equipment Management Services |
| EMTU | East-Med Tanks International |
| EMUU | Rez-1 |
| EN | Canadian Pacific Railway |
| EN | E and N Railway (Canadian Pacific Railway) |
| ENCX | EN ERCO International |
| ENDX | Ferroquadrum, S. A. de C. V. |
| ENDX | GATX de Mexico de CV |
| ENEX | Lake Shore Railway Historical Society |
| ENGX | Englehard Corporation |
| ENPX | Enterprise Products |
| ENR | E and N Railway (Canadian Pacific Railway) |
| ENRT | Electronic National Rail Timetable |
| ENRX | United States Enrichment Corporation |
| ENSZ | Norfolk Southern |