Amtrak's Vermonter is a 611-mile (983 km) passenger train service between St. Albans (Vermont), New York City and Washington, D.C. One trip runs in each direction per day.

The train replaced the overnight Montrealer which terminated in Montréal, Québec, Canada. When the Montrealer route was threatened with cancellation due to budget cuts, the State of Vermont stepped in to subsidize service as far north as St. Albans, near the Canadian border.

The tracks currently used were originally part of the Canadian National Railway, Central Vermont Railway, Boston and Maine Railroad, New Haven Railroad, New York Central Railroad, and Pennsylvania Railroad systems. The tracks currently used are owned by the New England Central Railroad (St. Albans, VT – Palmer, MA), CSX (Palmer, MA – Springfield, MA), Amtrak (Springfield, MA – New Haven, CT and New Rochelle, NY – Washington, DC), and Metro-North Railroad (New Haven, CT – New Rochelle, NY).

The Montrealer was originally a service of the Boston and Maine Railroad (BM), running between Montreal and Washington. The southbound line from 1972-1974 was called the Washingtonian, and the northbound was called the Montrealer. The Washingtonian was also Train 185, which came from New York and later along with most other regular trains on the Northeast Corridor, folded into one NortheastDirect in 1995. The Ambassador ran the same route but terminated in New York. Both services used the Boston and Maine's Connecticut River Railroad south of Vernon, Vermont, rather than the current route over the New England Central.