Finnair flights from London Heathrow Airport to Seattle (LHR - SEA)

LHR — SEA
11 Dec — 18 Dec1
1 adult
1 adult, Economy, 0 bags

Find Finnair flight deals from Heathrow to Seattle

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Cheapest Finnair flights from Heathrow to Seattle

Thu 10/1209:25 -
Nonstop10h 00m
Thu 24/1213:40 -
Nonstop9h 30m
Deal found 8/11£427
Tue 8/1210:35 -
2 stops22h 12m
Tue 15/1206:00 -
1 stop19h 40m
Deal found 9/11£448
Sun 15/1109:55 -
1 stop21h 15m
Sat 21/1117:24 -
1 stop31h 11m
Deal found 7/11£449
  • Can I get a flight from London Heathrow Airport to Seattle on Finnair for under £597?

    London Heathrow Airport to Seattle flights on Finnair are currently available under £597. 6 flights have been found by Cheapflights users under that amount. To find flights for your dates, click here.

Finnair flights from Heathrow to Seattle in 2026

One-way from

£450

Return from

£426

Popular in

July

Cheapest in

January

Average price (all airlines)

£540
Finnair
  • Finnair
  • 11/12-31/12
  • 1 total stop
  • 17h 56m total
  • London to Seattle
Finnair
  • Finnair
  • 26/4-4/5
  • 1 total stop
  • 41h 05m total
  • London to Seattle
Highest demand for flights from London Heathrow to Seattle/Tacoma Intl; 8% potential price increase.
Best time to find cheap flights from London Heathrow to Seattle/Tacoma Intl; 1% potential price drop.
Average price for all London Heathrow to Seattle/Tacoma Intl flights (one-way and round-trip).

Which month is the cheapest to fly Economy class from London Heathrow Airport to Seattle?

For Economy class flights, the cheapest month to fly this route is January. The most expensive months are May and July.

Best time to book a flight from Heathrow to Seattle

Have a flexible travel schedule? Discover the best time to fly to Seattle from Heathrow with our price prediction graph.
Estimated return price

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See what others are saying about Finnair

Finnair
7.6
Good
1,413 reviews
Overview

Entertainment

6.9

Food

6.7

Comfort

7.4

Boarding

7.6

Crew

8.2

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