What is the cheapest airline that flies from London to Seattle/Tacoma Intl?

WestJet, Air Canada, and United Airlines are the most popular carriers operating from London to Seattle/Tacoma Intl

What airlines fly to Seattle?

Alaska Airlines, Air Canada and WestJet are the top three most popular airlines that fly to Seattle from London, Ontario according to our data. Alaska Airlines is the first choice among our users, with 36% of people opting to fly with this airline when traveling to Seattle. Keep in mind that there are 6 different airlines that fly to Seattle on a routine basis, so you have a few additional options to choose from.

When did momondo last update prices for flights from London Airport to Seattle/Tacoma Intl Airport?

Prices for flights from London Airport to Seattle/Tacoma Intl Airport are updated daily.

How old do you have to be to fly from London Airport to Seattle/Tacoma Intl Airport?

The minimum age for a child to fly alone is five, but airlines that offer an unaccompanied minor (UNMR) service may have their own age limitations. Flight duration, scheduling, and layovers are among the considerations that may influence age limits. We recommend that you double-check with the airline you are booking with for travel from London Airport to Seattle/Tacoma Intl Airport.

What documentation or ID do you need to fly to Seattle/Tacoma Intl Airport?

The necessary travel and health documents for your Seattle/Tacoma Intl Airport trip may vary depending on your travel plans and individual circumstances. Generally, you should have various documents, such as a national ID card or driver's license and a passport that is valid for six months beyond your scheduled arrival date. We recommend seeking advice from your airline or a trusted third party, such as IATA.

$189 Cheap Flights from London to Seattle in 2025

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Find the cheapest flights from London, Ontario to Seattle

Round-trip

One-way

Cheap round-trip flights

8:00 pm - 12:33 pmYXU-SEA

19h 33m2 stops

2:05 pm - 5:12 amSEA-YXU

12h 07m1 stop

$359WestJet

Find Deal

Sat, Sep 20 - Tue, Sep 23

10:00 am - 7:31 pmYXU-SEA

12h 31m2 stops

7:15 pm - 9:19 amSEA-YXU

11h 04m2 stops

$401Air Canada

Find Deal

Sat, Sep 20 - Tue, Sep 23

6:00 am - 12:59 pmYXU-SEA

9h 59m1 stop

7:05 am - 7:07 pmSEA-YXU

9h 02m1 stop

$460WestJet

Find Deal

Mon, Sep 15 - Mon, Sep 22

3:50 pm - 10:59 pmYXU-SEA

10h 09m2 stops

4:55 pm - 3:17 pmSEA-YXU

19h 22m2 stops

$490United Airlines

Find Deal

Mon, Sep 15 - Mon, Sep 22

6:10 am - 10:59 amYXU-SEA

7h 49m1 stop

5:14 pm - 9:19 amSEA-YXU

13h 05m2 stops

$579United Airlines

Find Deal

Mon, Sep 15 - Mon, Sep 22

WestJet flights from London, Ontario to Seattle

Our best WestJet deals on London, Ontario to Seattle flight tickets

WestJet

Sep 20

YXU8:00 pmLondon

19h 33m

2 stops

SEA12:33 pmSeattle/Tacoma Intl

Sep 23

SEA2:05 pmSeattle/Tacoma Intl

12h 07m

1 stop

YXU5:12 amLondon

$359

Find similar

WestJet

Sep 15

YXU6:00 amLondon

9h 59m

1 stop

SEA12:59 pmSeattle/Tacoma Intl

Sep 22

SEA7:05 amSeattle/Tacoma Intl

9h 02m

1 stop

YXU7:07 pmLondon

$460

Find similar

United Airlines flights from London, Ontario to Seattle

Our best United Airlines deals on London, Ontario to Seattle flight tickets

United Airlines

Sep 15

YXU3:50 pmLondon

10h 09m

2 stops

SEA10:59 pmSeattle/Tacoma Intl

Sep 22

SEA4:55 pmSeattle/Tacoma Intl

19h 22m

2 stops

YXU3:17 pmLondon

$490

Find similar

United Airlines

Sep 15

YXU6:10 amLondon

7h 49m

1 stop

SEA10:59 amSeattle/Tacoma Intl

Sep 22

SEA5:14 pmSeattle/Tacoma Intl

13h 05m

2 stops

YXU9:19 amLondon

$579

Find similar

Fly from

Fly to

Route

Depart

Return

Price

LondonSeattle

YXU - SEA

YXUSEA

London

Sat 9/20

8:00 pm-12:33 pm

2 stops19h 33m

Seattle/Tacoma Intl

Tue 9/23

2:05 pm-5:12 am

1 stop12h 07m

$359

LondonSeattle

YXU - SEA

YXUSEA

London

Sat 9/20

10:00 am-7:31 pm

2 stops12h 31m

Seattle/Tacoma Intl

Tue 9/23

7:15 pm-9:19 am

2 stops11h 04m

$401

LondonSeattle

YXU - SEA

YXUSEA

London

Mon 9/15

6:00 am-12:59 pm

1 stop9h 59m

Seattle/Tacoma Intl

Mon 9/22

7:05 am-7:07 pm

1 stop9h 02m

$460

LondonSeattle

YXU - SEA

YXUSEA

London

Mon 9/15

3:50 pm-10:59 pm

2 stops10h 09m

Seattle/Tacoma Intl

Mon 9/22

4:55 pm-3:17 pm

2 stops19h 22m

$490

LondonSeattle

YXU - SEA

YXUSEA

London

Mon 9/15

6:10 am-10:59 am

1 stop7h 49m

Seattle/Tacoma Intl

Mon 9/22

5:14 pm-9:19 am

2 stops13h 05m

$579

LondonSeattle

YXU - SEA

YXUSEA

London

Mon 9/15

8:00 pm-7:14 pm

1 stop26h 14m

$189

LondonSeattle

YXU - SEA

YXUSEA

London

Sun 9/14

6:10 am-10:59 am

1 stop7h 49m

$221

LondonSeattle

YXU - SEA

YXUSEA

London

Mon 9/15

8:00 pm-3:02 pm

2 stops22h 02m

$238

LondonSeattle

YXU - SEA

YXUSEA

London

Sun 9/14

6:00 am-11:42 pm

2 stops20h 42m

$310

LondonSeattle

YXU - SEA

YXUSEA

London

Sun 9/14

8:00 pm-1:43 pm

3 stops20h 43m

$339

Flights are sorted by cheapest round-trip flights first.

Showing 1-10 of 11 resultsSorted by cheapest first

How to get the cheapest flight ticket from London, Ontario to Seattle

Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip

Prices

Airlines

What is the cheapest day to depart on your flight to Seattle?

On average, the least expensive day to fly to Seattle from London, Ontario is on a Saturday. momondo users have found tickets for Saturday departures for as low as $316. However, this price may fluctuate depending on the airline, the season, and holidays. On the other hand, Monday is the most expensive day to depart from London, Ontario because it is more convenient for both business and leisure travelers. As a result, prices tend to be around $449.

What is the cheapest time of day to depart on your flight to Seattle?

Flying to Seattle from London, Ontario in the afternoon is the least expensive time of day to depart. momondo users have found prices as low as $330 when looking at flights departing in the afternoon. Flights to Seattle are more costly in the morning, with an average ticket price of $477. Departure times in the morning fall within the peak daily travel times, which is why tickets can be more expensive.

When to book flights from London, Ontario to Seattle

Are you open to changing your travel dates? Check out the ideal times to fly from London, Ontario to Seattle according to our flight data. Find out which month and days have the cheapest flights.

Estimated round-trip price

Cheap London, Ontario to Seattle (YXU to SEA) flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from London, Ontario to Seattle

Best Price Found	$189
Fastest flight time	7h 49m
Direct flights	None
Airports in Seattle	1 airport

The best one-way flight to Seattle from London, Ontario in the past 72 hours is $189. The best round-trip flight deal from London, Ontario to Seattle found on momondo in the last 72 hours is $359.

The fastest flight from London, Ontario to Seattle takes 7h 49m

There are no direct flights from London, Ontario to Seattle. Popular non-direct route for this connection is London Airport - Seattle/Tacoma Intl Airport.

There is 1 airport near Seattle: Seattle/Tacoma Intl (SEA)

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How far is London to Seattle/Tacoma Intl by plane?
Seattle/Tacoma Intl is 1997.9 mi away from London. Flights usually cover this in 7h 49m, depending on flying conditions and air traffic around both airports.
When did momondo last update prices for flights from London Airport to Seattle/Tacoma Intl Airport?
Prices for flights from London Airport to Seattle/Tacoma Intl Airport are updated daily.
How old do you have to be to fly from London Airport to Seattle/Tacoma Intl Airport?
The minimum age for a child to fly alone is five, but airlines that offer an unaccompanied minor (UNMR) service may have their own age limitations. Flight duration, scheduling, and layovers are among the considerations that may influence age limits. We recommend that you double-check with the airline you are booking with for travel from London Airport to Seattle/Tacoma Intl Airport.
What documentation or ID do you need to fly to Seattle/Tacoma Intl Airport?
The necessary travel and health documents for your Seattle/Tacoma Intl Airport trip may vary depending on your travel plans and individual circumstances. Generally, you should have various documents, such as a national ID card or driver's license and a passport that is valid for six months beyond your scheduled arrival date. We recommend seeking advice from your airline or a trusted third party, such as IATA.

Leavenworth

Tacoma

SeaTac

Ocean Shores

Olympia

Renton

Kent

Federal Way

Puyallup

Lynnwood

Marysville

Tukwila

Kirkland

Lakewood

Fife

Centralia

Cle Elum

Shoreline

Westport

Redmond

Why use momondo?

Why should I use momondo to find a flight deal from London to Seattle?

To find the flight that best suits your needs, momondo gathers a range of flights from a large pool of different airlines and agents; you can then use our insights and filters to find and book the right flight to Seattle from London.

Can I find flights from London to Seattle with flexible booking policies on momondo?

momondo does allow users to show only those flights to Seattle from London which offer a flexible booking policy as well as other useful filters and features.

How can momondo help me find flights from London to Seattle?

momondo provides multiple filters to help you find the best flight to Seattle from London. Filter by price, airline, airports, cabin, aircraft, payment method, number of stops and more.

I’m not ready to book a flight from London to Seattle right now. Can momondo alert me if prices change?

If you are simply researching potential flights to Seattle, momondo offers a useful price alert feature which will track prices for flights to Seattle from London and alert you when they change.