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$171+ Cheap flights from London, ON (YXU) to Seattle (SEA)

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 10/26. Fares are subject to change and may not be available on all flights or dates of travel.
YXU — SEA
Oct 11 — Oct 181
Sat 10/11
Sat 10/18
1 adult, Economy
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Cheap flight deals from London to Seattle

Discover tips and strategies to find the most affordable flight options for your journey from London (YXU) to Seattle (SEA). 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 September 11, 2025.

Round-trip from

$296
(Kiwi.com)

One-way from

$171
(Trip.com)
From London to Seattle/Tacoma Intl
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One-way flight from London to Seattle/Tacoma Intl
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Find flight deals from London to Seattle

Cheapest flights from London to Seattle
Explore the most affordable flight options available from London to Seattle. Find the lowest fares from popular airlines and budget airlines, with prices last updated on September 11, 2025.

This Kiwi.com deal was found by Cheapflights users on 9/11. 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.
Wed 10/226:00 amYXU - SEA
1 stop9h 59mWestJet
Tue 11/113:10 pmSEA - YXU
1 stop25h 02mWestJet
Deal found 9/11$296
This Kiwi.com deal was found by Cheapflights users on 9/11. 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.
Sat 10/256:00 amYXU - SEA
1 stop9h 59mWestJet
Tue 11/113:10 pmSEA - YXU
1 stop25h 02mWestJet
Deal found 9/11$312
This Kiwi.com deal was found by Cheapflights users on 9/11. 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.
Wed 10/226:00 amYXU - SEA
1 stop9h 59mWestJet
Wed 11/123:10 pmSEA - YXU
1 stop25h 02mWestJet
Deal found 9/11$319
This Kiwi.com deal was found by Cheapflights users on 9/11. 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.
Fri 10/248:00 pmYXU - SEA
1 stop19h 59mWestJet
Thu 11/133:10 pmSEA - YXU
1 stop25h 02mWestJet
Deal found 9/11$321
This Kiwi.com deal was found by Cheapflights users on 9/11. 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.
Sat 10/256:00 amYXU - SEA
1 stop9h 59mWestJet
Wed 11/123:10 pmSEA - YXU
1 stop25h 02mWestJet
Deal found 9/11$333
This Kiwi.com deal was found by Cheapflights users on 9/11. 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.
Wed 10/226:00 amYXU - SEA
1 stop9h 59mMultiple Airlines
Wed 11/1211:10 pmSEA - YXU
2 stops17h 02mMultiple Airlines
Deal found 9/11$343
This Kiwi.com deal was found by Cheapflights users on 9/11. 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.
Wed 10/226:00 amYXU - SEA
1 stop9h 59mMultiple Airlines
Thu 11/1311:10 pmSEA - YXU
2 stops17h 02mMultiple Airlines
Deal found 9/11$356
This Kiwi.com deal was found by Cheapflights users on 9/11. 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.
Sat 10/256:00 amYXU - SEA
1 stop9h 59mMultiple Airlines
Tue 11/1111:10 pmSEA - YXU
2 stops17h 02mMultiple Airlines
Deal found 9/11$358
This Kiwi.com deal was found by Cheapflights users on 9/11. 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 10/208:00 pmYXU - SEA
1 stop19h 59mWestJet
Thu 11/133:10 pmSEA - YXU
1 stop25h 02mWestJet
Deal found 9/11$361
This Kiwi.com deal was found by Cheapflights users on 9/11. 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.
Wed 10/226:00 amYXU - SEA
1 stop9h 59mWestJet
Mon 11/1011:55 amSEA - YXU
2 stops28h 17mWestJet
Deal found 9/11$365
This Kiwi.com deal was found by Cheapflights users on 9/11. 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.
Fri 10/248:00 pmYXU - SEA
1 stop19h 59mMultiple Airlines
Wed 11/1211:10 pmSEA - YXU
2 stops17h 02mMultiple Airlines
Deal found 9/11$368
This Kiwi.com deal was found by Cheapflights users on 9/11. 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.
Sat 10/256:00 amYXU - SEA
1 stop9h 59mMultiple Airlines
Thu 11/1311:10 pmSEA - YXU
2 stops17h 02mMultiple Airlines
Deal found 9/11$370

Cheapflights Fare Finder

 
Customize your flight search to find flights from London to Seattle 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 2,558,603 searches. Data last updated September 11, 2025.
Use the filters below to find and compare flights from London to Seattle that are best for you.

Fly from

London

Fly to

Seattle

Route

Depart

Return

Price

LondonSeattle

YXU - SEA

YXUSEA

London

Thu 10/23

6:00 am-12:59 pm

1 stop9h 59m

Seattle/Tacoma Intl

Tue 11/11

3:10 pm-7:12 pm

1 stop25h 02m

$296

LondonSeattle

YXU - SEA

YXUSEA

London

Sat 10/25

6:00 am-12:59 pm

1 stop9h 59m

Seattle/Tacoma Intl

Thu 11/13

3:10 pm-7:12 pm

1 stop25h 02m

$312

LondonSeattle

YXU - SEA

YXUSEA

London

Wed 10/22

6:00 am-12:59 pm

1 stop9h 59m

Seattle/Tacoma Intl

Wed 11/12

3:10 pm-7:12 pm

1 stop25h 02m

$319

LondonSeattle

YXU - SEA

YXUSEA

London

Sat 10/25

6:15 am-2:16 pm

2 stops11h 01m

Seattle/Tacoma Intl

Sat 11/1

8:00 pm-9:46 am

2 stops10h 46m

$321

LondonSeattle

YXU - SEA

YXUSEA

London

Wed 10/22

6:00 am-12:59 pm

1 stop9h 59m

Seattle/Tacoma Intl

Tue 11/11

11:10 pm-7:12 pm

2 stops17h 02m

$343

LondonSeattle

YXU - SEA

YXUSEA

London

Fri 10/24

8:00 pm-12:59 pm

1 stop19h 59m

Seattle/Tacoma Intl

Wed 11/12

3:10 pm-7:12 pm

1 stop25h 02m

$343

LondonSeattle

YXU - SEA

YXUSEA

London

Thu 10/23

6:00 am-12:59 pm

1 stop9h 59m

Seattle/Tacoma Intl

Thu 11/13

11:10 pm-7:12 pm

2 stops17h 02m

$356

LondonSeattle

YXU - SEA

YXUSEA

London

Sat 10/25

6:00 am-12:59 pm

1 stop9h 59m

Seattle/Tacoma Intl

Wed 11/12

11:10 pm-7:12 pm

2 stops17h 02m

$358

LondonSeattle

YXU - SEA

YXUSEA

London

Sat 10/25

6:00 am-12:59 pm

1 stop9h 59m

Seattle/Tacoma Intl

Tue 11/11

11:10 pm-7:12 pm

2 stops17h 02m

$358

LondonSeattle

YXU - SEA

YXUSEA

London

Mon 10/20

8:00 pm-12:59 pm

1 stop19h 59m

Seattle/Tacoma Intl

Tue 11/11

3:10 pm-7:12 pm

1 stop25h 02m

$361

Flights are sorted by cheapest round-trip flights first.

Deals found on 9/11

Showing 1-10 of 18 results
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Best time to book a flight from London to Seattle

Have a flexible travel schedule? Discover the best time to fly to Seattle from London with our price prediction graph.
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.

Cheapflights Insights

Everything you need to know about your flight from London to Seattle

What is the cheapest month to book a flight from London, Ontario to Seattle?

Currently, January is the cheapest month in which you can book a flight from London, Ontario to Seattle (average of $238). Flying from London, Ontario to Seattle in June is currently the most expensive (average of $388). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

What is the cheapest time of day to fly from YXU to SEA?

Find hourly flight availability from London to Seattle. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated September 11, 2025.

Unlike in the morning, when flights are generally more expensive, you can save up to 31% on flights from London, Ontario to Seattle by exploring options for tickets at noon.

Related info for your journey

Find useful and relevant information for your journey from London to Seattle. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • How long is the flight from London, Ontario to Seattle?

    Departing from London, Ontario to Seattle will take you 9h 59m. There are 2000 mi between London, Ontario and Seattle. When browsing for deals, the options you’ll see will be for both nonstop flights and flights with stops.

  • Can I find deals for flights from London to Seattle that include hotel bookings?

    Yes. In addition to deals on London to Seattle flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from London to Seattle?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from London to Seattle.

  • Can I find deals for business class flights from London to Seattle?

    Yes. Cheapflights offers flight deals from London to Seattle by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

  • What is the cheapest month to book a flight from London, Ontario to Seattle?

    Currently, January is the cheapest month in which you can book a flight from London, Ontario to Seattle (average of $238). Flying from London, Ontario to Seattle in June is currently the most expensive (average of $388). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

Traveling to a place near Seattle?

Book flights to Seattle if you plan to visit one of these locations
SeaTac
Tukwila
Tacoma
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Edmonds
Leavenworth
Lacey
Renton
Olympia
Kent
Federal Way
Cle Elum
Puyallup
Chehalis
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Issaquah
Aberdeen
Shoreline

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