Norse Atlantic Airways is to serve Miami from Gatwick from September.
Flights to Fort Lauderdale will end and be replaced by the Miami route from September 18.
Passengers booked to Fort Lauderdale after September 17 will be rebooked onto the Miami service or offered a full refund, according to the airline.
Norse Atlantic started serving Fort Lauderdale and Orlando from Gatwick last week.
The low fare long-haul carrier today confirmed that flights to Miami will operate four times a week during the winter.
Tickets start at £450 return on the service which is introduced on September 18 using Boeing 787 Dreamliner aircraft.
Chief executive Bjorn Tore Larsen said: “We are pleased to be able to now offer the popular destination of Miami as part of our winter route network.
“Miami has high levels of passenger demand with both direct and connecting traffic volumes greater than other airports in the region.
“We look forward to being able to offer our cargo customers increased choice and flexibility as we begin operations from our new south Florida base in September.”