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$192+ Cheap flights from Seattle (SEA) to London, ON (YXU)

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 7/11. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — YXU
jul. 8 — jul. 151
mar. 7/8
mar. 7/15
1 adult, Economy
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Cheap 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 julio 3, 2025.

Round-trip from

$275
(Trip.com)

One-way from

$192
(Delta)
From Seattle/Tacoma Intl to London
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One-way flight from Seattle/Tacoma Intl to London
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Find flight deals from Seattle to London

Cheapest flights from Seattle to London
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 julio 3, 2025.

This Trip.com deal was found by Cheapflights users on 6/30. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
vie. 8/158:40 amSEA - YXU
1 stop7h 29mWestJet
vie. 8/226:00 amYXU - SEA
1 stop9h 58mWestJet
Deal found 6/30$275
This Booking.com deal was found by Cheapflights users on 6/30. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
vie. 8/157:35 pmSEA - YXU
1 stop6h 39mMultiple Airlines
vie. 8/229:55 amYXU - SEA
2 stops13h 46mMultiple Airlines
Deal found 6/30$313
This Air Canada deal was found by Cheapflights users on 7/3. 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.
jue. 7/107:15 pmSEA - YXU
2 stops11h 02mAir Canada
mar. 7/155:45 pmYXU - SEA
2 stops18h 36mAir Canada
Deal found 7/3$366
This United Airlines deal was found by Cheapflights users on 6/30. 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.
jue. 8/1412:20 amSEA - YXU
2 stops11h 42mUnited Airlines
vie. 8/226:15 amYXU - SEA
1 stop7h 45mUnited Airlines
Deal found 6/30$475

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 2,558,603 searches. Data last updated julio 3, 2025.
Use the filters below to find and compare flights from Seattle to London that are best for you.

Fly from

Seattle

Fly to

London

Route

Depart

Return

Price

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

vie. 8/15

8:40 am-7:09 pm

1 stop7h 29m

London

vie. 8/22

6:00 am-12:58 pm

1 stop9h 58m

$275

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

vie. 8/15

7:35 pm-5:14 am

1 stop6h 39m

London

vie. 8/22

9:55 am-8:41 pm

2 stops13h 46m

$313

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

sáb. 8/16

7:20 am-9:17 am

2 stops22h 57m

London

sáb. 8/23

9:55 am-8:41 pm

2 stops13h 46m

$428

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

jue. 8/14

12:20 am-3:02 pm

2 stops11h 42m

London

vie. 8/22

6:15 am-11:00 am

1 stop7h 45m

$475

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

vie. 7/11

7:35 pm-5:14 am

1 stop6h 39m

$192

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

vie. 7/11

7:20 am-9:27 pm

2 stops11h 07m

$532

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

jue. 7/31

7:05 am-7:09 pm

1 stop9h 04m

$540

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

jue. 7/31

5:26 pm-3:02 pm

2 stops18h 36m

$591

Flights are sorted by cheapest round-trip flights first.

Deals found on 7/1

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.
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.

Reviews of airlines servicing London

Get insights into the airlines that provide service to London. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to London. Reviews last updated julio 3, 2025.
Get a feel of what it's like to fly with Delta, United Airlines, and WestJet from Seattle to London by reading reviews from past customers. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
Delta
8.0
Very good
7,982 reviews

Overall

8.0

Comfort

7.9

Food

7.3

Crew

8.5

Boarding

8.2

Entertainment

7.9

Reviews

1 / 20
10.0
Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!
Delta
8.0
Very good
7,982 reviews
Delta
8.0
Very good
7,982 reviews

Overall

8.0

Comfort

7.9

Food

7.3

Crew

8.5

Boarding

8.2

Entertainment

7.9

Reviews

1 / 20
10.0
Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!
United Airlines
7.4
Good
8,861 reviews
Delta
8.0
Very good
7,982 reviews

Overall

8.0

Comfort

7.9

Food

7.3

Crew

8.5

Boarding

8.2

Entertainment

7.9

Reviews

1 / 20
10.0
Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!
WestJet
7.2
Good
2,917 reviews
Delta
8.0
Very good
7,982 reviews

Overall

8.0

Comfort

7.9

Food

7.3

Crew

8.5

Boarding

8.2

Entertainment

7.9

Reviews

1 / 20
10.0
Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!
Air Canada
7.1
Good
9,681 reviews
Delta
8.0
Very good
7,982 reviews

Overall

8.0

Comfort

7.9

Food

7.3

Crew

8.5

Boarding

8.2

Entertainment

7.9

Reviews

1 / 20
10.0
Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!

Related info for your journey

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

  • What are the cheapest airlines flying from Seattle to London, Ontario round-trip?

    Cheapflights users have booked flights from Seattle to London, Ontario round-trip from $275. Other airlines that can offer you cheap pricing are Air Canada, from $428, and United Airlines, from $475.

  • What are the cheapest airlines to fly from Seattle to London, Ontario one-way?

    The cheapest airline one-way is Delta, with whom users have recently found tickets for as low as $192. However, be on the lookout for offers from Air Canada and WestJet, as they are both options that can get you from Seattle to London, Ontario for a low price.

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

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

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

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

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

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

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Alternative routes for Seattle to London

See prices for flight routes from nearby airports that may be better suited for you.
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Top 2 airlines flying from Seattle to London

Discover the top 2 airlines that operate flights from Seattle to London. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated julio 3, 2025.
AirlineCheapestAverageFlexibilityOn-time
United AirlinesCheapest$185Average$660FlexibilityNo cancel feeOn-time69%
Air CanadaCheapest$248Average$603FlexibilityNo cancel feeOn-time67%

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