Finnair plans an expansion of its transatlantic network next summer with the addition of a Seattle service.
Flights from Stockholm to New York and Los Angeles throughout the summer are also planned.
Seattle will be served three times a week on Mondays, Wednesdays and Fridays from Helsinki starting on June 1.
Connecting flights from Heathrow to Helsinki rise to four a day for summer 2022, with wide bodied aircraft operating two of the four daily frequencies.
Departing west-bound passengers will appear to land at the US west coast city 15 minutes before they take off due to the international time difference, with flights leaving Helsinki at 5.55pm and arriving into Seattle at 5.40pm local time, the same day.
The return flight leaves Seattle at 7.20pm and arrives in the Finnish capital at 2.50pm the following day.
Finnair chief commercial officer Ole Orver said: “We are delighted to offer more connections between the US and Northern Europe.
“Seattle is a fantastic destination for leisure travellers who enjoy vibrant city life and beautiful nature. We also expect this new connection to be a pleasant surprise for many business travellers.”