London Stansted airport is to be sold to Manchester Airports Group under a £1.5 billion ($2.4 billion) cash transaction.
Heathrow Airport Holdings, the operating company for Stansted, has confirmed an agreement to sell the airport.
It states that it expects the sale to complete by the end of February. The sale follows divestment of London Gatwick and Edinburgh airports, which the operator had run under its former name BAA.
BAA was ordered by UK competition regulators to sell some of its airports after an in-depth investigation into the UK airport market.
London Stansted is notable as a gateway to the UK capital for low-cost carriers, including Ryanair - which had been participating in the sale process until October last year.
Fourteen airlines operate from Stansted airport and it handles some 17.5 million passengers per year.
Heathrow chief Colin Matthews says the operating company will "continue to focus" on improving the remaining airports in its portfolio: Heathrow, Glasgow, Aberdeen and Southampton.
Manchester Airports Group runs East Midlands and Bournemouth airports alongside its main Manchester facility.