The Department for Transport (DfT) has pledged to continue subsidising flights between Derry in Northern Ireland and London.
Loganair will operate the PSO – public service obligation – route, which will relocate from Stansted airport to Southend airport.
It will maintain service at 26 flights a week onboard a 49-seater aircraft.
Southend, meanwhile, is served by six direct trains an hour to and from London.
Transport secretary Grant Shapps said the route was a vital business and tourism link, and underlined the government’s £300 million commitment to supporting growth in the UK’s devolved nations.