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 $661 round trip and CA $411 one way. Prices and availability subject to change. Additional terms may apply.

Mon, Oct 27 - Wed, Nov 5
SEA
Seattle
LHR
London
CA $661 Roundtrip, found 22 hours ago
CA $661
Roundtrip
found 22 hours ago
Select Aer Lingus flight, departing Mon, Oct 27 from Seattle to London, returning Wed, Nov 5, priced at CA $661 found 22 hours ago
Wed, Oct 22 - Wed, Nov 5
SEA
Seattle
LHR
London
CA $663 Roundtrip, found 1 day ago
CA $663
Roundtrip
found 1 day ago
Select Aer Lingus flight, departing Wed, Oct 22 from Seattle to London, returning Wed, Nov 5, priced at CA $663 found 1 day ago
Mon, Oct 6 - Wed, Oct 22
SEA
Seattle
LHR
London
CA $663 Roundtrip, found 4 days ago
CA $663
Roundtrip
found 4 days ago
Select Aer Lingus flight, departing Mon, Oct 6 from Seattle to London, returning Wed, Oct 22, priced at CA $663 found 4 days ago
Mon, Oct 6 - Wed, Oct 15
SEA
Seattle
LHR
London
CA $664 Roundtrip, found 1 day ago
CA $664
Roundtrip
found 1 day ago
Select Aer Lingus flight, departing Mon, Oct 6 from Seattle to London, returning Wed, Oct 15, priced at CA $664 found 1 day ago
Mon, Oct 27 - Wed, Nov 5
SEA
Seattle
LHR
London
CA $692 Roundtrip, found 22 hours ago
CA $692
Roundtrip
found 22 hours ago
Select Lufthansa flight, departing Mon, Oct 27 from Seattle to London, returning Wed, Nov 5, priced at CA $692 found 22 hours ago
Wed, Sep 10 - Thu, Oct 9
SEA
Seattle
LHR
London
CA $699 Roundtrip, found 6 days ago
CA $699
Roundtrip
found 6 days ago
Select Virgin Atlantic flight, departing Wed, Sep 10 from Seattle to London, returning Thu, Oct 9, priced at CA $699 found 6 days ago
Sat, Sep 27 - Fri, Oct 10
SEA
Seattle
LHR
London
CA $701 Roundtrip, found 4 days ago
CA $701
Roundtrip
found 4 days ago
Select Delta flight, departing Sat, Sep 27 from Seattle to London, returning Fri, Oct 10, priced at CA $701 found 4 days ago
Mon, Oct 6 - Wed, Oct 22
SEA
Seattle
LHR
London
CA $710 Roundtrip, found 4 days ago
CA $710
Roundtrip
found 4 days ago
Select Virgin Atlantic flight, departing Mon, Oct 6 from Seattle to London, returning Wed, Oct 22, priced at CA $710 found 4 days ago
Mon, Oct 6 - Wed, Oct 22
SEA
Seattle
LHR
London
CA $710 Roundtrip, found 4 days ago
CA $710
Roundtrip
found 4 days ago
Select Air Canada flight, departing Mon, Oct 6 from Seattle to London, returning Wed, Oct 22, priced at CA $710 found 4 days ago
Wed, Oct 22 - Tue, Oct 28
SEA
Seattle
LHR
London
CA $710 Roundtrip, found 3 days ago
CA $710
Roundtrip
found 3 days ago
Select British Airways flight, departing Wed, Oct 22 from Seattle to London, returning Tue, Oct 28, priced at CA $710 found 3 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.