JetBlue will add a second daily Heathrow-JFK service from next week.
The move will see the airline’s Gatwick service reduce to a single daily frequency.
In June the airline will add France to its transatlantic operation, with a daily route from Charles de Gaulle to JFK, followed by a Paris-Boston service.
The airline began operating daily flights between the US and UK in August 2021.
A JetBlue spokesperson said: “Slots at Heathrow are prized, and while this change will have no effect on overall capacity, the airline gains further access to one of the most lucrative markets in the world and solidifies its competitive position.”