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

LHR — SEA
12 Jul — 19 Jul1
1 adult
1 adult, Economy, 0 bags

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Cheapest Finnair flights from Heathrow to Seattle
Explore the most affordable Finnair flight options available from Heathrow to Seattle. Find the lowest fares with prices last updated on 12 June 2026.

Sat 4/709:50
LHR
-
SEA
Nonstop9h 45m
Finnair
Tue 14/717:40
SEA
-
LHR
1 stop15h 25m
Finnair
Deal found 12/6£543
Mon 20/709:15
LHR
-
SEA
1 stop34h 25m
Finnair
Thu 30/707:10
SEA
-
LHR
1 stop17h 55m
Finnair
Deal found 12/6£570
Thu 9/709:45
LHR
-
SEA
1 stop23h 07m
Finnair
Wed 22/720:20
SEA
-
LHR
Nonstop9h 25m
Finnair
Deal found 12/6£592

  • Can I get a flight from London Heathrow Airport to Seattle on Finnair for under £671?

    London Heathrow Airport to Seattle flights on Finnair are currently available under £671. 10 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

Find detailed information about Finnair flights from Heathrow to Seattle. Explore the options provided by Finnair to plan your journey from Heathrow to Seattle. Data last updated 12 June 2026.

One-way from

£444

Return from

£524

Popular in

July

Cheapest in

January

Average price (all airlines)

£647
Finnair
  • Finnair
  • 19/8
  • Nonstop
  • 9h 45m total
  • London to Seattle
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Finnair
  • Finnair
  • 5/9-28/9
  • 1 total stop
  • 29h 13m total
  • London to Seattle
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Highest demand for flights from London Heathrow to Seattle/Tacoma Intl; 10% potential price increase.
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Best time to find cheap flights from London Heathrow to Seattle/Tacoma Intl; 1% potential price drop.
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Average price for all London Heathrow to Seattle/Tacoma Intl flights (one-way and round-trip).
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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 October and May.

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
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

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See what others are saying about Finnair

Read reviews and see what other travellers are saying about their experiences with Finnair. Get insights from real passengers regarding the airline's services, customer satisfaction, and overall travel experience. Use these reviews to inform your decision when choosing Finnair for your next flight. Reviews last updated 12 June 2026.
Finnair
7.7
Good
1,406 reviews
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Overview

Boarding

7.7

Entertainment

6.9

Crew

8.2

Food

6.7

Comfort

7.4

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