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

LHR — SEA
13 Jun — 20 Jun1
1 adult
1 adult, Economy, 0 bags

Cheapflights users flying from London to Seattle on Finnair typically fly into Seattle/Tacoma Intl and depart from London Heathrow. Select your dates above for pricing.

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 14 May 2026.

One-way from

£416

Return from

£579

Popular in

July

Cheapest in

February

Average price (all airlines)

£611
Finnair
  • Finnair
  • 7/10
  • Nonstop
  • 9h 45m total
  • London to Seattle
Finnair
  • Finnair
  • 9/6-25/6
  • Nonstop
  • 19h 00m total
  • London to Seattle
Highest demand for flights from London Heathrow to Seattle/Tacoma Intl; 9% 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).
  • How do most travelers feel about Finnair?

    The general consensus from 1,393 Cheapflights users is that Finnair is a 7.6/10. Select your travel dates above for updated prices on flights from London Heathrow Airport to Seattle (LHR-SEA).

  • Can I get a flight from London Heathrow Airport to Seattle on Finnair for under £665?

    London Heathrow Airport to Seattle flights on Finnair are currently available under £665. 10 flights have been found by Cheapflights users under that amount. To find flights for your dates, click here.

Find Finnair flight deals from Heathrow to Seattle

Enter your travel dates to find the best prices.

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 14 May 2026.

Tue 9/609:50
LHR
-
SEA
Nonstop9h 45m
Finnair
Thu 25/613:30
SEA
-
LHR
Nonstop9h 15m
Finnair
Deal found 12/5£579
Tue 9/609:50
LHR
-
SEA
Nonstop9h 45m
Finnair
Tue 16/620:20
SEA
-
LHR
Nonstop9h 25m
Finnair
Deal found 12/5£596
Mon 8/609:50
LHR
-
SEA
Nonstop9h 45m
Finnair
Mon 15/620:20
SEA
-
LHR
Nonstop9h 25m
Finnair
Deal found 11/5£600

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 February.

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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Fly from Heathrow to Seattle on another airline

Consider alternative airlines that service the Seattle area. Flight routes are based on user searches made on Cheapflights and were last updated on 14 May 2026.

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 14 May 2026.
Finnair
7.6
Good
1,393 reviews
Overview

Food

6.7

Crew

8.2

Comfort

7.4

Entertainment

6.9

Boarding

7.7

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