Adria Airways will operate the two-hour service three times a week between June and October. It is the first route linking London with Maribor.
Announcing the news at a press conference with the Mayor of Maribor and representatives from Southend Airport, Adria Airways Chief Executive Mark Anžur said: "We are absolutely excited about our new scheduled connection from the second biggest city in Slovenia, Maribor to London Southend Airport.
“We are looking forward to a beginning of a successful partnership and bringing our passengers to both attractive destinations, with the new route offering the travellers from both countries to explore new destinations and everything both countries have to offer.
“We are very pleased to welcome travellers from UK to enjoy the diversity of Slovenia and all that it has to offer; from mountains to seaside."
Flights go on sale from March 30th with return prices starting from 69 euros.