A deal has been agreed by easyJet to double the number of passengers it flies from Luton during the next decade to more than 9 million a year.
It comes within days of the budget carrier sealing a seven-year arrangement to allow for expansion at Gatwick.
The airline, which was founded and is based at Luton, said the deal could see traffic more than double from four to nine million passengers a year.
EasyJet has agreed to increase the frequency of flights on some routes, as well as add new destinations.
The airline’s capacity at Luton would rise by 20% in the first year as part of the agreement.
The expansion could also see as many as 2,500 jobs created at the airport and in the local area, easyJet said.
The agreement comes as the airport’s operator awaits approval for £100 million investment plans to expand its capacity to 18 million passengers a year.
The plans, which involve extending the airport’s terminal and improving road access, are being assessed by the Department for Communities and Local Government.
Last year 9.7 million passengers passed through Luton and the airport wants to increase that to 18 million a year.
Spanish airports authority Aena took over the operation of Luton last year for €502 million, promising to redevelop the UK’s fifth biggest airport by passenger numbers.
Aena and private equity partner Ardian said: “This deal is a major endorsement of our long-term financial investment and commitment to London Luton airport.
“We see our role as enabling the airport to fulfil its potential in becoming London’s local airport, delivering a better experience for our customers and supporting Luton’s economy.
“EasyJet’s announcement is a significant step forward along this journey.”
The airline’s chief executive Carolyn McCall said: “We are looking forward to working with the airport, and the new concession owners Ardian and Aena.
“Their financial investment and long-term commitment to developing London Luton were a key factor in our agreeing to this new deal and will help us deliver our plans.”
Airport managing director Glyn Jones added: “It’s a really important deal for the airport.
“It’s a massive vote of confidence in the airport and in our new shareholders, Ardian and Aena who have been really clear about their desire, not only to make the airport bigger, but also to make it a lot better, to improve the passenger experience.”