Ryanair is to base three aircraft at London Southend from April to operate 13 routes to eight countries.
Announcing the $300 million investment today, Ryanair said it would offer more than 55 weekly flights from the airport, carrying around one million passengers a year.
Last winter, Ryanair suspended some of its flights from Southend, including some domestic services.
However, it said its new base at the airport from April 2019 would create an additional 750 on site jobs.
It will fly from Southend next year to Alicante, Barcelona Reus, Bilbao, Brest, Corfu, Cluj, Dublin, Faro, Kosice, Malaga, Milan Bergamo, Palma and Venice.
Dublin will get a twice daily service from Southend, while the other destinations will be served by up to five flights a week.
Ryanair's chief commercial officer David O'Brien said: "We are pleased to add London Southend Airport to our UK base network. Ryanair guests travelling to and from London and the Essex area can now enjoy low fares on a choice of 13 routes through London Southend's exceptionally passenger friendly terminal.
"Southend Airport's train station will deliver direct services from the terminal to London Liverpool St and also the new Crossrail service (opening in 2019), making the airport even more accessible from all parts of London."
Stobart Group CEO Warwick Brady said: "We are delighted to welcome Ryanair and its guests to London Southend in S2019. We have a clear and focused strategy to grow our airport to welcome over five million passengers a year by 2022.
"This news will help us achieve that aim, and Ryanair will be a valuable partner to Stobart Group in developing London Southend airport with 13 routes and six new destinations, allowing us to play a key role in solving London's capacity crisis.
"We look forward to delivering a great service to Ryanair guests to ensure we support the extraordinary growth of Ryanair operations out of London."
Virgin announces first flight to South America13 Jun - 18
Virgin has announced it will start flying between London and Sao Paulo in Brazil next year.
BA to add third Saudi route13 Jun - 18
British Airways will fly daily from Heathrow to Dammam in Saudi Arabia from December 1 2019.
Turkish Airlines brings back Gatwick-Bodrum flights13 Jun - 18
Turkish Airlines is bringing back London Gatwick to Bodrum flights this summer.
Starting from Apr…
Emirates to launch additional London flight13 Jun - 18
Emirates is to launch a second daily flight between Dubai and Stansted on July 1.
The additional …
Avani to open trio of Vietnam hotels13 Jun - 18
Minor Hotels Group's Avani hotel brand has inked a deal to bring three new hotels to Vietnam.
Qatar unveils new economy class and more routes13 Jun - 18
Qatar Airways has unveiled its new economy class experience and seven new routes.
The news was an…
Loganair to add flights to Derry13 Jun - 18
Loganair will take over a key route between London and Northern Ireland following the collapse of F…
Emirates launching Bangkok, Phnom Penh route13 Jun - 18
Gulf carrier Emirates will connect Phnom Penh and Bangkok with a new daily service from its Dubai h…
Delta restarting seasonal Rio flights from New York JFK13 Jun - 18
Delta Air lines will resume nonstop seasonal service between New York's JFK and Rio de Janeiro next…
Travelodge opens hotel close to Ashford International13 Jun - 18
Travelodge has opened a hotel close to Ashford International railway station and is now seeking oth…