British Airways is to operate the only route between Heathrow and Newquay this summer after Flybe switched its London flights to Gatwick.
British Airways will run flights from the Cornish airport to the London hub between July 2 and September 7.
Flights will operate on Mondays, Thursdays, Fridays, Saturdays and Sundays.
Return fares start at £90, rising to £250 in Club Europe.
Flybe announced last month it would switch its Heathrow-Newquay service with Gatwick in March as it tackles a cash-flow crisis.
On Tuesday the government was reported to be considering a stake in Flybe to save the struggling carrier.
Ministers are said to be in talks with Flybe and the European Commission to avoid any breach of EU state aid rules.
More:Comment: What did the government agree with Flybe?
British Airways network and alliances director Neil Chernoff said: “We know that customers enjoy exploring the UK as much as they do going further afield, and Newquay has so much to offer, especially in the summer months.”
Cornwall airport Newquay interim director Richard Thomasson added: “We are delighted British Airways will be flying to Cornwall this summer and to be able to continue to offer this vital link between Cornwall and Heathrow.
“With such a major global carrier we will be able to offer our passengers one-stop access to the world, while worldwide investors and tourists will benefit from an easier connection to our stunning county.”