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 $877 round trip and CA $351 one way. Prices and availability subject to change. Additional terms may apply.

Thu., 6 Mar. - Thu., 13 Mar.
SEA
Seattle
LHR
London
CA $877 Roundtrip, found 6 days ago
CA $877
Roundtrip
found 6 days ago
Select Icelandair flight, departing Thu., 6 Mar. from Seattle to London, returning Thu., 13 Mar., priced at CA $877 found 6 days ago
Wed., 5 Mar. - Wed., 12 Mar.
SEA
Seattle
LHR
London
CA $884 Roundtrip, found 2 days ago
CA $884
Roundtrip
found 2 days ago
Select Delta flight, departing Wed., 5 Mar. from Seattle to London, returning Wed., 12 Mar., priced at CA $884 found 2 days ago
Sun., 28 Sep. - Tue., 14 Oct.
SEA
Seattle
LHR
London
CA $886 Roundtrip, found 18 hours ago
CA $886
Roundtrip
found 18 hours ago
Select Scandinavian Airlines flight, departing Sun., 28 Sep. from Seattle to London, returning Tue., 14 Oct., priced at CA $886 found 18 hours ago
Tue., 11 Feb. - Mon., 3 Mar.
SEA
Seattle
LHR
London
CA $900 Roundtrip, found 6 days ago
CA $900
Roundtrip
found 6 days ago
Select Virgin Atlantic flight, departing Tue., 11 Feb. from Seattle to London, returning Mon., 3 Mar., priced at CA $900 found 6 days ago
Tue., 25 Feb. - Tue., 4 Mar.
SEA
Seattle
LHR
London
CA $902 Roundtrip, found 4 days ago
CA $902
Roundtrip
found 4 days ago
Select American Airlines flight, departing Tue., 25 Feb. from Seattle to London, returning Tue., 4 Mar., priced at CA $902 found 4 days ago
Mon., 20 Oct. - Wed., 29 Oct.
SEA
Seattle
LHR
London
CA $909 Roundtrip, found 2 days ago
CA $909
Roundtrip
found 2 days ago
Select Lufthansa flight, departing Mon., 20 Oct. from Seattle to London, returning Wed., 29 Oct., priced at CA $909 found 2 days ago
Mon., 3 Mar. - Wed., 19 Mar.
SEA
Seattle
LHR
London
CA $937 Roundtrip, found 20 hours ago
CA $937
Roundtrip
found 20 hours ago
Select Aer Lingus flight, departing Mon., 3 Mar. from Seattle to London, returning Wed., 19 Mar., priced at CA $937 found 20 hours ago
Sun., 2 Mar. - Tue., 11 Mar.
SEA
Seattle
LHR
London
CA $973 Roundtrip, just found
CA $973
Roundtrip
just found
Select JetBlue Airways flight, departing Sun., 2 Mar. from Seattle to London, returning Tue., 11 Mar., priced at CA $973 just found
Tue., 11 Mar. - Tue., 25 Mar.
SEA
Seattle
LHR
London
CA $990 Roundtrip, found 1 day ago
CA $990
Roundtrip
found 1 day ago
Select Air Canada flight, departing Tue., 11 Mar. from Seattle to London, returning Tue., 25 Mar., priced at CA $990 found 1 day ago
Tue., 22 Apr. - Tue., 29 Apr.
SEA
Seattle
LHR
London
CA $1,036 Roundtrip, found 2 hours ago
CA $1,036
Roundtrip
found 2 hours ago
Select British Airways flight, departing Tue., 22 Apr. from Seattle to London, returning Tue., 29 Apr., priced at CA $1,036 found 2 hours 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.