| Abbreviation | Railroad Name |
| NA | Na
|
| NGDS | Nacogdoches & Southeastern
|
| NAFX | NAFX
|
| NAPA VALLE | Napa Valley
|
| NAPER JUNC | Napierville Junction
|
| NARRAGANSE | Narragansett Pier
|
| NASA | Nasa
|
| NCSL | Nash. Chatt. & St. Louis
|
| NACZ | Nashville & Ashland City |
| NAT IRON | Nat Iron Works
|
| NTR | Natches Trace Railroad
|
| NUR | Natchez, Urania & Ruston
|
| NCCX | National Car Co.
|
| NDEM | National Of Mexico
|
| NOX | National Oil Co.
|
| NAT PCK | National Packing Co.
|
| NAT STEEL | National Steel Car (Canada)
|
| NAVAJO | Navajo Trucking
|
| NED PCK | Needham Packing Co.
|
| NELA | Nelson & Albemarle
|
| NCO | Nevada California & Oregon |
| NCB | Nevada Copper Belt
|
| NEV COPPER | Nevada Copper Belt
|
| NCNG | Nevada County Narrow Gauge
|
| NEVADA NOR | Nevada Northern
|
| NVPX | Nevada Power Co.
|
| NBS | New Brunswick Southern |
| NEW HAMPSH | New Hampshire
|
| NHVT | New Hampshire & Vermont
|
| NH | New Haven
|
| NJ | New Jersey
|
| NJT | New Jersey Transit
|
| NOLC | New Orleans & Lower Coast
|
| NOPB | New Orleans Public Belt
|
| NSW | New South Wahles
|
| NPS | Newark Pub Serv Coor. Tran. |
| NSR | Newburg & South Shore
|
| NEZPERCE | Nezperce
|
| NKP | Nickel Plate
|
| NBNR | Nicolet Badger Northern
|
| NISX | NISX
|
| NJNY | NJ & New York
|
| NJII | NJ, Indiana & Illinois
|
| NM DOT | NM Dot Rail Runner
|
| NW | Norfolk & Western
|
| NS | Norfolk Southern
|
| NACC | North American Car Co.
|
| NCSTL | North Carolina & St Louis
|
| NCDOT | North Carolina DOT
|
| NCTR | North Central Texas
|
| NLG | North Louisiana & Gulf
|
| NORTH SHOR | North Shore Lines
|
| NBAT | Northampton & Bath
|
| NORTH OKLA | Northeast Oklahoma (elec)
|
| NAR | Northern Alberta (Canadian Natl)
|
| NP | Northern Pacific
|
| NRC | Northern Refrigeerator Car
|
| NSPX | Northern States Power Company
|
| NST | Northstar |
| NOKL | Northwestern Oklahoma
|
| NWP | Northwestern Pacific
|
| NSTL | Norwood & St. Lawrence
|
| NYA | NY & Atlantic Railway Co.
|
| NYLB | NY & Long Branch
|
| NYNE | NY & New England
|
| NYOM | NY & Oswego Midland
|
| NYC | NY Central
|
| NYCH | NY Central & Hudson River
|
| NYCS | NY Chicago & St. Louis
|
| NYCT | NY City Transit
|
| NYLE | NY Lake Erie
|
| NYNHH | NY New Haven & Hartford
|
| NYOW | NY Ontario & West.
|
| NYSW | NY Susquehanna & West.
|
| HYA | NY&A
|