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

Wander Wisely with exceptional service, 24/7 supportOpens in a new window

Feel at ease with free flight cancellations within 24 hours of booking

Change your flight without a fee on select flights

Find The Best Dates To Fly

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

The cheapest flights to Heathrow found within the past 7 days were CA $805 round trip and CA $479 one way. Prices and availability subject to change. Additional terms may apply.

Mon, Apr 13 - Tue, Apr 28
SEA
Seattle
LHR
London
CA $805 Roundtrip, found 5 days ago
CA $805
Roundtrip
found 5 days ago
Select Icelandair flight, departing Mon, Apr 13 from Seattle to London, returning Tue, Apr 28, priced at CA $805 found 5 days ago
Fri, Sep 11 - Thu, Oct 1
SEA
Seattle
LHR
London
CA $872 Roundtrip, found 22 hours ago
CA $872
Roundtrip
found 22 hours ago
Select Scandinavian Airlines flight, departing Fri, Sep 11 from Seattle to London, returning Thu, Oct 1, priced at CA $872 found 22 hours ago
Mon, Apr 13 - Wed, Apr 22
SEA
Seattle
LHR
London
CA $881 Roundtrip, found 4 days ago
CA $881
Roundtrip
found 4 days ago
Select Aer Lingus flight, departing Mon, Apr 13 from Seattle to London, returning Wed, Apr 22, priced at CA $881 found 4 days ago
Tue, Dec 1 - Thu, Dec 10
SEA
Seattle
LHR
London
CA $912 Roundtrip, found 3 days ago
CA $912
Roundtrip
found 3 days ago
Select Virgin Atlantic flight, departing Tue, Dec 1 from Seattle to London, returning Thu, Dec 10, priced at CA $912 found 3 days ago
Mon, May 4 - Mon, May 11
SEA
Seattle
LHR
London
CA $917 Roundtrip, found 5 days ago
CA $917
Roundtrip
found 5 days ago
Select American Airlines flight, departing Mon, May 4 from Seattle to London, returning Mon, May 11, priced at CA $917 found 5 days ago
Mon, Apr 13 - Wed, Apr 22
SEA
Seattle
LHR
London
CA $928 Roundtrip, found 4 days ago
CA $928
Roundtrip
found 4 days ago
Select British Airways flight, departing Mon, Apr 13 from Seattle to London, returning Wed, Apr 22, priced at CA $928 found 4 days ago
Mon, Apr 13 - Wed, Apr 22
SEA
Seattle
LHR
London
CA $928 Roundtrip, found 4 days ago
CA $928
Roundtrip
found 4 days ago
Select British Airways flight, departing Mon, Apr 13 from Seattle to London, returning Wed, Apr 22, priced at CA $928 found 4 days ago
Tue, Dec 1 - Thu, Dec 10
SEA
Seattle
LHR
London
CA $932 Roundtrip, found 3 days ago
CA $932
Roundtrip
found 3 days ago
Select Lufthansa flight, departing Tue, Dec 1 from Seattle to London, returning Thu, Dec 10, priced at CA $932 found 3 days ago
Tue, Jan 12 - Tue, Jan 26
SEA
Seattle
LHR
London
CA $956 Roundtrip, found 1 day ago
CA $956
Roundtrip
found 1 day ago
Select KLM flight, departing Tue, Jan 12 from Seattle to London, returning Tue, Jan 26, priced at CA $956 found 1 day ago
Wed, Aug 12 - Thu, Aug 27
SEA
Seattle
LHR
London
CA $969 Roundtrip, found 5 days ago
CA $969
Roundtrip
found 5 days ago
Select Alaska Airlines flight, departing Wed, Aug 12 from Seattle to London, returning Thu, Aug 27, priced at CA $969 found 5 days 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.