Passengers using Luton airport rose by almost a quarter in March to 1.05 million.
The 24.4% year-on-year rise came as this year’s early Easter fell into last month.
The increase marks the first time that more than one million passengers passed through the airport in March.
This came as Vueling and Transavia started new services from the airport since the start of the year.
Further network expansion has come from Blue Air starting flights to Turin last week and a service to Larnaca in Cyprus from April 25.
Thomas Cook Airlines is to run charter routes from Luton to Ibiza, Menorca, Corfu and Majorca from summer 2017, as previously reported by Travel Weekly.
Airport chief executive, Nick Barton, said: “The arrival of Thomas Cook is a very exciting milestone for the airport. Coming as we mark two consecutive years of growth, it is further evidence of Luton airport’s growing popularity among passengers.
“Luton airport is well set to continue its strong recent growth as we are making good progress with our £110 million transformation plans.
“Our redevelopment and expansion will not only create a more enjoyable experience for passengers, but also allow us to offer an ever-widening selection of exciting new destinations.”