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Cheap flights from London, ON to Seattle from C$ 338

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 5/4. Fares are subject to change and may not be available on all flights or dates of travel.
YXU — SEA
26 Feb — 5 Mar1
1 adult

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 21 February 2025.

Round-trip from

C$ 585

One-way from

C$ 338

Popular in

April

Cheapest in

September

Average price

C$ 1,291
WestJet
  • WestJet
  • 4/4-21/4
  • 4 total stops
  • 45h 43m total
  • London to Seattle
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United Airlines
  • United Airlines
  • 5/4
  • 1 total stop
  • 9h 01m total
  • London to Seattle
Search Deals
Highest demand for flights based on searches. 34% potential increase in price (C$ 546 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 14% potential price decrease (C$ 132 potential savings vs. average RT price).
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Average for round-trip flights in February 2025
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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 21 February 2025.

Fri 4/48:00 p.m.YXU - SEA
2 stops17h 00mWestJet
Mon 21/411:30 a.m.SEA - YXU
2 stops28h 43mWestJet
Deal found 19/2C$ 585
Sun 6/48:00 p.m.YXU - SEA
1 stop21h 21mMultiple Airlines
Sun 13/49:15 p.m.SEA - YXU
1 stop11h 05mMultiple Airlines
Deal found 20/2C$ 598
Sat 5/43:25 p.m.YXU - SEA
1 stop9h 01mUnited Airlines
Sat 19/47:33 p.m.SEA - YXU
2 stops10h 40mUnited Airlines
Deal found 19/2C$ 621
Fri 4/43:25 p.m.YXU - SEA
1 stop9h 01mAir Canada
Sun 20/46:05 a.m.SEA - YXU
1 stop11h 13mAir Canada
Deal found 19/2C$ 700

Find flights from London to Seattle within your budget

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 629,999 searches. Data last updated 21 February 2025.

Fly from

London

Fly to

Seattle

Route

Depart

Return

Price

LondonSeattle

YXU - SEA

YXUSEA

London

Fri 4/4

8:00 p.m.-10:00 a.m.

2 stops17h 00m

Seattle/Tacoma Intl

Mon 21/4

11:30 a.m.-7:13 p.m.

2 stops28h 43m

C$ 585

LondonSeattle

YXU - SEA

YXUSEA

London

Sun 6/4

8:00 p.m.-2:21 p.m.

1 stop21h 21m

Seattle/Tacoma Intl

Sun 13/4

9:15 p.m.-11:20 a.m.

1 stop11h 05m

C$ 598

LondonSeattle

YXU - SEA

YXUSEA

London

Sat 5/4

3:25 p.m.-9:26 p.m.

1 stop9h 01m

Seattle/Tacoma Intl

Sat 19/4

7:33 p.m.-9:13 a.m.

2 stops10h 40m

C$ 621

LondonSeattle

YXU - SEA

YXUSEA

London

Fri 4/4

3:25 p.m.-9:26 p.m.

1 stop9h 01m

Seattle/Tacoma Intl

Sun 20/4

6:05 a.m.-8:18 p.m.

1 stop11h 13m

C$ 700

LondonSeattle

YXU - SEA

YXUSEA

London

Sat 5/4

3:25 p.m.-9:26 p.m.

1 stop9h 01m

C$ 338

Flights are sorted by cheapest round-trip flights first.

Deals found on 19/2

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.

Travel insights for flights from London to Seattle

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

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 C$ 262). Flying from London, Ontario to Seattle in April is currently the most expensive (average of C$ 382). 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 21 February 2025.

One of the essential ways to save on airfare from London, Ontario to Seattle is to remain as flexible as possible. Flights that are in the morning tend to be the most expensive. A flight at noon could potentially save you up to 2% on airfare.

Rainfall in Seattle by month

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

In terms of precipitation, rainfall in Seattle ranges from 18.0 - 168.0 mm per month. November is typically the wettest month, when rainfall can reach 168.0 mm. July is typically the driest time to visit Seattle when rainfall is around 18.0 mm.

Temperature in Seattle by month

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

If weather is an important factor for your trip to Seattle, 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 19.0 C. Travellers hoping to avoid the cold should look outside of December, when temperatures are typically at their lowest (around 5.0 C).

Reviews of airlines servicing Seattle

Get insights into the airlines that provide service to Seattle. 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 Seattle. Reviews last updated 21 February 2025.
United Airlines
7.4
Good
8,766 reviews
Check prices

Entertainment

7.1

Boarding

7.7

Food

6.7

Comfort

7.3

Overall

7.4

Crew

8.1

Reviews

1 / 20

4.0
Okay

Patti,Feb 2025

FCO - EWR

The food was inedible! We are in the food business and aren’t sure who got this contract. But prisoners eat better. The food was so bad. I ate just a small amount and it made me nauseous. Everything is over microwaved too. And what is with the options? Vegan and vegetarian, but no keto or carnivore? I get that may be more expensive. But I’d gladly pay if it even was an option. But it’s not. There are many fresh options that could have been offered that don’t have to be heated too!

United Airlines
7.4
Good
8,766 reviews
United Airlines
7.4
Good
8,766 reviews
Check prices

Entertainment

7.1

Boarding

7.7

Food

6.7

Comfort

7.3

Overall

7.4

Crew

8.1

Reviews

1 / 20

4.0
Okay

Patti,Feb 2025

FCO - EWR

The food was inedible! We are in the food business and aren’t sure who got this contract. But prisoners eat better. The food was so bad. I ate just a small amount and it made me nauseous. Everything is over microwaved too. And what is with the options? Vegan and vegetarian, but no keto or carnivore? I get that may be more expensive. But I’d gladly pay if it even was an option. But it’s not. There are many fresh options that could have been offered that don’t have to be heated too!

WestJet
7.2
Good
2,801 reviews
United Airlines
7.4
Good
8,766 reviews
Check prices

Entertainment

7.1

Boarding

7.7

Food

6.7

Comfort

7.3

Overall

7.4

Crew

8.1

Reviews

1 / 20

4.0
Okay

Patti,Feb 2025

FCO - EWR

The food was inedible! We are in the food business and aren’t sure who got this contract. But prisoners eat better. The food was so bad. I ate just a small amount and it made me nauseous. Everything is over microwaved too. And what is with the options? Vegan and vegetarian, but no keto or carnivore? I get that may be more expensive. But I’d gladly pay if it even was an option. But it’s not. There are many fresh options that could have been offered that don’t have to be heated too!

Air Canada
7.0
Good
8,748 reviews
United Airlines
7.4
Good
8,766 reviews
Check prices

Entertainment

7.1

Boarding

7.7

Food

6.7

Comfort

7.3

Overall

7.4

Crew

8.1

Reviews

1 / 20

4.0
Okay

Patti,Feb 2025

FCO - EWR

The food was inedible! We are in the food business and aren’t sure who got this contract. But prisoners eat better. The food was so bad. I ate just a small amount and it made me nauseous. Everything is over microwaved too. And what is with the options? Vegan and vegetarian, but no keto or carnivore? I get that may be more expensive. But I’d gladly pay if it even was an option. But it’s not. There are many fresh options that could have been offered that don’t have to be heated too!

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.

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

    According to our current data, WestJet (C$ 585), United Airlines (C$ 621), and Air Canada (C$ 700) offers the cheapest pricing from London, Ontario to Seattle. WestJet is 20% cheaper than the average price of flights available within the next 90 days to this destination.

  • 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 C$ 262). Flying from London, Ontario to Seattle in April is currently the most expensive (average of C$ 382). 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

Travelling to a place near London?

Book flights to London if you plan to visit one of these locations
SeaTac
Tukwila
Marysville
Bothell
Leavenworth
Tacoma
Olympia
Lynnwood

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Top airline flying from London to Seattle

Discover the top airline that operate flights from London to Seattle. 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 629,999 searches. Data last updated 21 February 2025.
AirlineCheapestAverageFlexibilityOn-time
Air CanadaCheapestC$ 371AverageC$ 514FlexibilityNo cancel feeOn-time67%
Search Air Canada flights

Fly with Cheapflights

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How does Cheapflights help users find flights from London to Seattle?

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Why should you use Cheapflights to find cheap flight tickets from London to Seattle?

Cheapflights helps you find that perfect flight to Seattle from London by searching from hundreds of airlines and agencies you know and love. We are also free to use, in case you were wondering!

Can Cheapflights find flights from London to Seattle with no change fees?

Certainly. Search results for flights to Seattle from London shown to you on Cheapflights can be narrowed down with different useful search filters, which includes flexible booking options.

Can Cheapflights notify me if prices for flights from London to Seattle become cheaper?

Yes, Cheapflights offers price alerts on London to Seattle flights so you can book your travel at the perfect time. Price Alerts can be enabled by clicking the bell icon next to the flight deals above and providing your email address where you want to receive the alerts.

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