$533+ Cheap flights from Seattle (SEA) to London, ON (YXU)
This is the cheapest round-trip flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 11/12. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — YXU
Nov 19 — Nov 261
Round-trip
1 adult, Economy
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Find cheap flights from Seattle to London with Cheapflights
1. Tell us where you want to go
Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”2. Select your favorite providers
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Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.Cheap flight deals from Seattle to London
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Cheapest flights from Seattle to LondonExplore the most affordable flight options available from Seattle to London. Find the lowest fares from popular airlines and budget airlines, with prices last updated on October 20, 2026.
Explore the most affordable flight options available from Seattle to London. Find the lowest fares from popular airlines and budget airlines, with prices last updated on October 20, 2026.
This WestJet deal was found by Cheapflights users on 10/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure WestJet is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/122:30 pm -
1 stop12h 05m
Thu 11/196:40 am -
1 stop10h 00m
Deal found 10/14![WestJet logo]()
$533
This Kiwi.com deal was found by Cheapflights users on 10/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/305:48 pm -
1 stop8h 47m
Mon 12/710:15 am -
1 stop30h 17m
Deal found 10/16![Multiple Airlines logo]()
$682
This United Airlines deal was found by Cheapflights users on 10/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/512:20 pm -
2 stops23h 22m
Sun 11/89:15 am -
2 stops33h 57m
Deal found 10/15![United Airlines logo]()
$914
This WestJet deal was found by Cheapflights users on 10/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure WestJet is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/302:30 pm -
1 stop12h 05m
Mon 12/76:40 am -
1 stop10h 00m
Deal found 10/16![WestJet logo]()
$922
This United deal was found by Cheapflights users on 10/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/56:30 pm -
2 stops22h 57m
Sun 11/89:15 am -
1 stop14h 44m
Deal found 10/15![Multiple Airlines logo]()
$1,054
This United Airlines deal was found by Cheapflights users on 10/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/127:35 pm -
2 stops21h 52m
Thu 11/193:25 pm -
2 stops10h 42m
Deal found 10/14![United Airlines logo]()
$1,084
This Air Canada deal was found by Cheapflights users on 10/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/57:45 am -
1 stop9h 42m
Sun 11/89:15 am -
1 stop14h 44m
Deal found 10/15![Air Canada logo]()
$1,105
Best flights from Seattle to LondonDiscover carefully curated flight deals from Seattle to London that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated October 20, 2026.
Discover carefully curated flight deals from Seattle to London that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated October 20, 2026.
This Kiwi.com deal was found by Cheapflights users on 10/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/309:53 pm -
2 stops28h 42m
Mon 12/710:15 am -
1 stop30h 17m
Deal found 10/16![Multiple Airlines logo]()
$693
This WestJet deal was found by Cheapflights users on 10/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure WestJet is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/122:30 pm -
1 stop12h 05m
Thu 11/196:40 am -
1 stop10h 00m
Deal found 10/14![WestJet logo]()
$856
This United Airlines deal was found by Cheapflights users on 10/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/512:20 pm -
2 stops23h 22m
Sun 11/89:15 am -
2 stops33h 57m
Deal found 10/15![United Airlines logo]()
$914
This Justfly.com deal was found by Cheapflights users on 10/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Justfly.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 3/143:30 pm -
1 stop12h 05m
Sun 3/286:15 am -
1 stop31h 51m
Deal found 10/19![Multiple Airlines logo]()
$785
This Mytrip deal was found by Cheapflights users on 10/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 3/1412:00 pm -
3 stops15h 35m
Thu 4/87:40 am -
1 stop10h 00m
Deal found 10/19![Multiple Airlines logo]()
$920
This United Airlines deal was found by Cheapflights users on 10/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 3/146:29 am -
2 stops23h 08m
Thu 4/85:30 am -
3 stops17h 40m
Deal found 10/19![United Airlines logo]()
$1,069
This United Airlines deal was found by Cheapflights users on 10/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/127:35 pm -
2 stops21h 52m
Thu 11/193:25 pm -
2 stops10h 42m
Deal found 10/14![United Airlines logo]()
$1,084
This United deal was found by Cheapflights users on 10/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/56:30 pm -
2 stops22h 57m
Sun 11/89:15 am -
1 stop14h 44m
Deal found 10/15![Multiple Airlines logo]()
$1,054
This United Airlines deal was found by Cheapflights users on 10/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 3/186:10 am -
2 stops12h 39m
Thu 4/85:30 am -
3 stops17h 40m
Deal found 10/19![United Airlines logo]()
$1,131
Last-minute flights from Seattle to LondonDiscover last-minute flight deals from Seattle to London. Data last updated October 20, 2026 and is based on user searches.
Discover last-minute flight deals from Seattle to London. Data last updated October 20, 2026 and is based on user searches.
This United Airlines deal was found by Cheapflights users on 10/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/512:20 pm -
2 stops23h 22m
Sun 11/89:15 am -
2 stops33h 57m
Deal found 10/15![United Airlines logo]()
$914
This United deal was found by Cheapflights users on 10/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/56:30 pm -
2 stops22h 57m
Sun 11/89:15 am -
1 stop14h 44m
Deal found 10/15![Multiple Airlines logo]()
$1,054
This Air Canada deal was found by Cheapflights users on 10/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/57:45 am -
1 stop9h 42m
Sun 11/89:15 am -
1 stop14h 44m
Deal found 10/15![Air Canada logo]()
$1,105
This WestJet deal was found by Cheapflights users on 10/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure WestJet is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/122:30 pm -
1 stop12h 05m
Thu 11/196:40 am -
1 stop10h 00m
Deal found 10/14![WestJet logo]()
$533
This United Airlines deal was found by Cheapflights users on 10/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/127:35 pm -
2 stops21h 52m
Thu 11/193:25 pm -
2 stops10h 42m
Deal found 10/14![United Airlines logo]()
$1,084
This Kiwi.com deal was found by Cheapflights users on 10/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/305:48 pm -
1 stop8h 47m
Mon 12/710:15 am -
1 stop30h 17m
Deal found 10/16![Multiple Airlines logo]()
$682
This WestJet deal was found by Cheapflights users on 10/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure WestJet is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/302:30 pm -
1 stop12h 05m
Mon 12/76:40 am -
1 stop10h 00m
Deal found 10/16![WestJet logo]()
$922
Find flight deals from Seattle to London
Discover tips and strategies to find the most affordable flight options for your journey from Seattle (SEA) to London (YXU). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated October 20, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $533 (WestJet) |
Cheapflights Fare Finder
Customize your flight search to find flights from Seattle to London that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 7,457,451 searches. Data last updated October 20, 2026.
Use the filters below to find and compare flights from Seattle to London that are best for you.
Fly from
Fly to
Route
Depart
Return
Cheapest round-trip
SeattleLondon
SEA Seattle/Tacoma Intl - YXU London
SEAYXU
Seattle/Tacoma Intl
Mon 11/30
9:53 pm-5:35 am
2 stops28h 42m
London
Mon 12/7
10:15 am-1:32 pm
1 stop30h 17m
$693
SeattleLondon
SEA Seattle/Tacoma Intl - YXU London
SEAYXU
Seattle/Tacoma Intl
Sun 3/14
3:30 pm-6:35 am
1 stop12h 05m
London
Sun 3/28
6:15 am-11:06 am
1 stop31h 51m
$785
Quickest round-trip
SeattleLondon
SEA Seattle/Tacoma Intl - YXU London
SEAYXU
Seattle/Tacoma Intl
Thu 11/12
2:30 pm-5:35 am
1 stop12h 05m
London
Thu 11/19
6:40 am-1:40 pm
1 stop10h 00m
$856
SeattleLondon
SEA Seattle/Tacoma Intl - YXU London
SEAYXU
Seattle/Tacoma Intl
Thu 11/5
12:20 pm-2:42 pm
2 stops23h 22m
London
Sun 11/8
9:15 am-4:12 pm
2 stops33h 57m
$914
SeattleLondon
SEA Seattle/Tacoma Intl - YXU London
SEAYXU
Seattle/Tacoma Intl
Sun 3/14
12:00 pm-6:35 am
3 stops15h 35m
London
Thu 4/8
7:40 am-2:40 pm
1 stop10h 00m
$920
SeattleLondon
SEA Seattle/Tacoma Intl - YXU London
SEAYXU
Seattle/Tacoma Intl
Thu 11/5
6:30 pm-8:27 pm
2 stops22h 57m
London
Sun 11/8
9:15 am-8:59 pm
1 stop14h 44m
$1,054
SeattleLondon
SEA Seattle/Tacoma Intl - YXU London
SEAYXU
Seattle/Tacoma Intl
Sun 3/14
6:29 am-8:37 am
2 stops23h 08m
London
Thu 4/8
5:30 am-8:10 pm
3 stops17h 40m
$1,069
SeattleLondon
SEA Seattle/Tacoma Intl - YXU London
SEAYXU
Seattle/Tacoma Intl
Thu 11/12
7:35 pm-8:27 pm
2 stops21h 52m
London
Thu 11/19
3:25 pm-11:07 pm
2 stops10h 42m
$1,084
SeattleLondon
SEA Seattle/Tacoma Intl - YXU London
SEAYXU
Seattle/Tacoma Intl
Thu 3/18
6:10 am-9:49 pm
2 stops12h 39m
London
Thu 4/8
5:30 am-8:10 pm
3 stops17h 40m
$1,131
Sorted by cheapest first
- Most accurate provider: When it comes to deals on Seattle-London, Ontario flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Seattle-London, Ontario flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Seattle-London, Ontario flight searches over the past month and is updated monthly.
- Most trusted provider: When it comes to deals on Seattle-London, Ontario flights, Cheapflights users trust FlightHub the most. FlightHub has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for Seattle-London, Ontario flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.
Best time to book a flight from Seattle to London
Have a flexible travel schedule? Discover the best time to fly to London from Seattle with our price prediction graph.
SEA-YXU
Estimated round-trip 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.
Related info for your journey
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