Passengers carried by Norwegian rose by 8% in April to almost 2.3 million, helped by “high demand” for long-haul flights.
Europe’s third largest low cost carrier saw a 168,000 rise in passengers over the same month last year.
The load factor increased by 2.1 percentage points to 84.5% despite an 11% rise in total capacity.
Norwegian is the third largest airline at Gatwick and serves seven US destinations with low-fare transatlantic flights
Chief executive Bjørn Kjos said: “We are very pleased that an increasing number of travellers are choosing Norwegian, not least business travellers.
“We see growth in the Nordics and in Europe in general, and the high demand for long-haul routes keeps growing.”
The airline took delivery of one Boeing 737-800 and one Boeing 787-9 Dreamliner in April as part of plans to introduce 21 new aircraft in 2016.