Cheap Flights From Seattle - Tacoma Intl. (SEA) To Heathrow (LHR)

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Cheapest Flights from Seattle (SEA) to London (LHR)

The cheapest flights to Heathrow found within the past 7 days were CA $723 round trip and CA $341 one way. Prices and availability subject to change. Additional terms may apply.

Mon, Mar 16 - Tue, Mar 24
SEA
Seattle
LHR
London
CA $723 Roundtrip, found 6 days ago
CA $723
Roundtrip
found 6 days ago
Select Icelandair flight, departing Mon, Mar 16 from Seattle to London, returning Tue, Mar 24, priced at CA $723 found 6 days ago
Wed, Feb 18 - Wed, Feb 25
SEA
Seattle
LHR
London
CA $782 Roundtrip, found 4 days ago
CA $782
Roundtrip
found 4 days ago
Select British Airways flight, departing Wed, Feb 18 from Seattle to London, returning Wed, Feb 25, priced at CA $782 found 4 days ago
Sun, Mar 1 - Fri, Mar 20
SEA
Seattle
LHR
London
CA $807 Roundtrip, found 2 days ago
CA $807
Roundtrip
found 2 days ago
Select Lufthansa flight, departing Sun, Mar 1 from Seattle to London, returning Fri, Mar 20, priced at CA $807 found 2 days ago
Wed, Aug 19 - Fri, Aug 28
SEA
Seattle
LHR
London
CA $815 Roundtrip, found 5 days ago
CA $815
Roundtrip
found 5 days ago
Select Aer Lingus flight, departing Wed, Aug 19 from Seattle to London, returning Fri, Aug 28, priced at CA $815 found 5 days ago
Sun, Mar 1 - Fri, Mar 20
SEA
Seattle
LHR
London
CA $824 Roundtrip, found 2 days ago
CA $824
Roundtrip
found 2 days ago
Select British Airways flight, departing Sun, Mar 1 from Seattle to London, returning Fri, Mar 20, priced at CA $824 found 2 days ago
Mon, Feb 2 - Tue, Feb 17
SEA
Seattle
LHR
London
CA $824 Roundtrip, found 11 hours ago
CA $824
Roundtrip
found 11 hours ago
Select Air Canada flight, departing Mon, Feb 2 from Seattle to London, returning Tue, Feb 17, priced at CA $824 found 11 hours ago
Tue, Mar 17 - Tue, Mar 24
SEA
Seattle
LHR
London
CA $832 Roundtrip, found 1 day ago
CA $832
Roundtrip
found 1 day ago
Select American Airlines flight, departing Tue, Mar 17 from Seattle to London, returning Tue, Mar 24, priced at CA $832 found 1 day ago
Wed, May 6 - Mon, May 18
SEA
Seattle
LHR
London
CA $854 Roundtrip, found 5 days ago
CA $854
Roundtrip
found 5 days ago
Select Air France flight, departing Wed, May 6 from Seattle to London, returning Mon, May 18, priced at CA $854 found 5 days ago
Sat, Mar 21 - Tue, Mar 31
SEA
Seattle
LHR
London
CA $855 Roundtrip, found 1 day ago
CA $855
Roundtrip
found 1 day ago
Select Delta flight, departing Sat, Mar 21 from Seattle to London, returning Tue, Mar 31, priced at CA $855 found 1 day ago
Sun, Mar 22 - Mon, Mar 30
SEA
Seattle
LHR
London
CA $855 Roundtrip, found 1 day ago
CA $855
Roundtrip
found 1 day ago
Select KLM flight, departing Sun, Mar 22 from Seattle to London, returning Mon, Mar 30, priced at CA $855 found 1 day ago

Frequently asked questions

Are there direct flights from Seattle - Tacoma Intl. Airport (SEA) to Heathrow Airport (LHR)?
Sometimes, travel is all about the journey; sometimes the magic is in the destination. But if you just want to get to where you're headed fast, multiple airlines have direct flights from Seattle - Tacoma Intl. Airport (SEA) to LHR, including Virgin Atlantic and American Airlines.
What airlines fly from Sea-Tac Airport to London Heathrow?
With a few airlines operating direct flights from Sea-Tac Airport to LHR, you shouldn't have a problem finding that perfect fare. Below are some of the most reliable air carriers:

  • Virgin Atlantic - (VS) with 30 flights every month
  • American Airlines - (AA) with 30 flights every month
  • British Airways - (BA) with 30 flights every month
  • Delta - (DL) with 4 flights every month

What is the best day to buy a plane ticket?
Airfares offered on Friday tend to be the cheapest, according to flight demand on Travelocity.ca in 2021. Purchasing your airfares on a Thursday or Saturday can also provide better value, however our advice if you're looking to save money is to avoid booking on a Wednesday or Sunday. Our data shows that those two days have the highest ticket values on average, so keep this in mind if you're browsing flight deals.
What are the cheapest days to fly?
Frequent travellers may already know this, but earlier in the week is often the cheapest time to fly. Flights departing on a Monday are the cheapest of the week. Since flights towards the middle of the week tend to be more popular, this causes the prices to rise. This is why, on average, airfares booked on Travelocity.ca in 2021 were most expensive for Wednesday departures.
How far in advance can you book a flight?
Here's the deal: It is typically possible to start comparing international airfares on Travelocity.ca up to 12 months in advance. However, it does depend on the carrier as not all airlines release their prices that far out. According to our 2021 flight demand trends, last minute planners can still bag a bargain with some of the cheapest fares appearing 2-4 weeks prior to their travel dates.*According to flight demand on Travelocity.ca from January to December 2021. Savings are subject to change and may vary depending on selections made.
*Price based on the lowest price found within past 24 hours and based upon one night stay for two adults over the next thirty days. Prices and availability subject to change. Additional terms may apply.