The exact launch date and timetable are to be confirmed, but flights will operate four times weekly.
This is the fourth North American route for Norwegian from London Gatwick after New York, Los Angeles and Fort Lauderdale.
The airline will also fly to Puerto Rico from November 2015.
This news will be welcomed by London Gatwick as it is the first time in many years Boston has been served by the airport.
Norwegian has stated in the Financial Times that it has ambitions to serve many more long haul destinations from the UK beyond the Americas and to Africa and Asia.