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$154+ 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 4/7. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — YXU
Feb 4 — Feb 111
Tue 2/4
Tue 2/11
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 January 30, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$349
(Kiwi.com)

One-way from

$188
(Trip.com)
Provider with most accurate pricing for Seattle/Tacoma Intl-London flight deals.
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Provider most trusted by Cheapflights users for Seattle/Tacoma Intl-London flights.
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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 January 30, 2025.

This Kiwi.com deal was found by Cheapflights users on 1/30. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/113:02 pmSEA - YXU
2 stops25h 11mMultiple Airlines
Tue 3/188:00 pmYXU - SEA
1 stop21h 21mMultiple Airlines
Deal found 1/30$349
This Kiwi.com deal was found by Cheapflights users on 1/30. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/113:15 pmSEA - YXU
1 stop24h 58mWestJet
Tue 3/188:00 pmYXU - SEA
1 stop21h 21mWestJet
Deal found 1/30$382
This Gotogate deal was found by Cheapflights users on 1/30. 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 Gotogate is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 3/166:05 amSEA - YXU
1 stop11h 15mAir Canada
Sun 3/235:15 amYXU - SEA
2 stops12h 15mAir Canada
Deal found 1/30$437
This United Airlines deal was found by Cheapflights users on 1/30. 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.
Sun 3/166:05 amSEA - YXU
1 stop11h 15mUnited Airlines
Sun 3/233:20 pmYXU - SEA
1 stop9h 10mUnited Airlines
Deal found 1/30$464

Find flights from Seattle to London within your budget

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 January 30, 2025.

Fly from

Any airport

Fly to

Any airport

Route

Depart

Return

Price

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Tue 3/11

3:02 pm-7:13 pm

2 stops25h 11m

London

Tue 3/18

8:00 pm-2:21 pm

1 stop21h 21m

$349

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Tue 3/11

3:15 pm-7:13 pm

1 stop24h 58m

London

Tue 3/18

8:00 pm-2:21 pm

1 stop21h 21m

$382

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Sun 3/16

6:05 am-8:20 pm

1 stop11h 15m

London

Sun 3/23

5:15 am-2:30 pm

2 stops12h 15m

$437

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Sun 3/16

6:05 am-8:20 pm

1 stop11h 15m

London

Sun 3/23

3:20 pm-9:30 pm

1 stop9h 10m

$464

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Mon 4/7

11:30 am-7:13 pm

2 stops28h 43m

$154

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Sun 3/16

3:12 pm-7:13 pm

3 stops49h 01m

$188

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Sun 3/16

6:05 am-8:20 pm

1 stop11h 15m

$224

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Sun 3/16

6:05 am-8:20 pm

1 stop11h 15m

$231

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Sun 3/16

7:50 pm-7:13 pm

2 stops20h 23m

$382

Flights are sorted by cheapest round-trip flights first.

Deals found on 1/30

  • 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.
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.

Travel insights for flights from Seattle to London

Get recent, data-driven insights about flights from Seattle to London including ideal travel times, pricing trends, and more.

Rainfall in London by month

Plan your trip to London by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in London, Ontario ranges from 2.8 - 3.9 inches per month. January is typically the wettest month, when rainfall can reach 3.9 in. March is typically the driest time to visit London, Ontario when rainfall is around 2.8 in.

Temperature in London by month

Plan your trip to London by taking into account the average temperature totals by month.

If weather is an important factor for your trip to London, Ontario, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 68.0 F. Travelers looking to avoid the cold should look outside of February, when temperatures are typically at their lowest (around 21.2 F).

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 January 30, 2025.
Delta
8.0
Very good
8,450 reviews

Comfort

8.0

Entertainment

7.9

Overall

8.0

Boarding

8.2

Food

7.3

Crew

8.5

Reviews

1 / 20

10.0
Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.

Delta
8.0
Very good
8,450 reviews
Delta
8.0
Very good
8,450 reviews

Comfort

8.0

Entertainment

7.9

Overall

8.0

Boarding

8.2

Food

7.3

Crew

8.5

Reviews

1 / 20

10.0
Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.

United Airlines
7.4
Good
8,906 reviews
Delta
8.0
Very good
8,450 reviews

Comfort

8.0

Entertainment

7.9

Overall

8.0

Boarding

8.2

Food

7.3

Crew

8.5

Reviews

1 / 20

10.0
Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.

WestJet
7.2
Good
2,817 reviews
Delta
8.0
Very good
8,450 reviews

Comfort

8.0

Entertainment

7.9

Overall

8.0

Boarding

8.2

Food

7.3

Crew

8.5

Reviews

1 / 20

10.0
Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.

Air Canada
7.0
Good
8,641 reviews
Delta
8.0
Very good
8,450 reviews

Comfort

8.0

Entertainment

7.9

Overall

8.0

Boarding

8.2

Food

7.3

Crew

8.5

Reviews

1 / 20

10.0
Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.

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 $382. Other airlines that can offer you cheap pricing are Air Canada, from $437, and United Airlines, from $464.

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

    The cheapest airline one-way is United Airlines, with whom users have recently found tickets for as low as $224. However, be on the lookout for offers from Air Canada and Delta, 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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Top airline flying from Seattle to London

Discover the top airline 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 January 30, 2025.
AirlineCheapestAverageFlexibilityOn-time
Air CanadaCheapest$205Average$530FlexibilityNo cancel feeOn-time67%
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