Inaugurated by the Canadian Pacific Railway (CPR) as a "limited stop" service on September 25, 1955, The Atlantic Limited used numbers 41/42 (westbound/eastbound) and took the schedule and equipment for what were previously numbered trains between Montreal, Quebec (Windsor Station) and Saint John, New Brunswick (Union Station).
While The Atlantic Limited name was only used officially after 1955 on the Montreal-Saint John service, the name, or a variation of it, has possibly seen use for a service which operated on CPR and CPR-subsidiary Soo Line between Minneapolis, Minnesota, via Sault Ste.