| Abbreviation | Definition |
|---|---|
| BLE | Bessemer and Lake Erie Railroad |
| BLE | Bessemer and Lake Erie Railroad Company |
| BLHR | Buffalo & Lake Huron Railway |
| BLKM | Black Mesa and Lake Powell |
| BLKM | Black Mesa and Lake Powell Railway |
| BLKU | Bulkhaul |
| BLKU | Bulkhaul Company Limited |
| BLKZ | Mid-American Intermodal Equipment Corporation |
| BLMR | Blue Mountain Railroad |
| BLMR | Blue Mountain Railroad Incorporated |
| BLOL | Bloomer Line |
| BLOR | Bloomer Line |
| BLU | Blue Ridge Southern Railroad |
| BM | Baltimore and Maine |
| BM | Boston and Maine Railroad (Pan Am Railways) |
| BM | ST Rail system |
| BMAZ | Better Asset Management (TAL International) |
| BMAZ | Transamerica Leasing Incorporated (Better Asset Management) |
| BMCX | Bluewater Michigan Chapter |
| BMDX | Belle Meade Distilling Corp (GE Railcar Services Corporation) |