The Greyhound bus (tel. 800-231-2222 or visit www.greyhound.com) makes its route from/to Montreal to Burlington Airport and on to Boston. One carry-on and 1 bag is free; an add'l bag is $10; bags over 50 lbs are charged $25.
NOTE: if heading to Montreal, you need to present your passport, passport card,enhanced drivers license or Nexus card.
Amtrak stops in Burlington heading towards Boston (visit: www.amtrak.com).
The Megabus express serves US & Canada (visit: www.megabus.com/rouemap.espx - in multiple languages).
Ferries cross Lake Champlain year-round (open: ferries.com/crossing-schedule-rates/grand-isle-to-plattsburgh-ferry ).