The busiest routes were Amsterdam, Geneva and Bucharest as more passengers chose to travel from the airport for both business and leisure. Ryanair also announced a new route to Krakow, which will begin flying in October.
The upgrade of the terminal is now complete, with a second executive lounge due to open in April.
London Luton chief executive Alberto Martin said: “The diversity in destinations that we offer is just one reason why more passengers are choosing to travel from LLA, both for business and leisure.
“Since the opening of our newly upgraded terminal, our passengers have been able to experience a more comfortable journey thanks to the addition of new shops and restaurants, more seats, and new boarding gates.”