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

WestJet is the most popular carrier 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 37% 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.

$145 Cheap Flights from London to Seattle in 2025/26

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0 bags

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Find the cheapest flights from London, Ontario to Seattle

Round-trip

One-way

Cheap round-trip flights

Enter your travel dates to find the best prices.

8:10 pm - 2:19 pm

YXU

SEA

21h 09m1 stop

3:10 pm - 6:35 am

SEA

YXU

12h 25m1 stop

$525WestJet

lun., mar. 2 - mié., mar. 4

5:10 am - 3:01 pm

YXU

SEA

12h 51m2 stops

5:50 am - 9:21 pm

SEA

YXU

12h 31m2 stops

$529Air Canada

lun., mar. 2 - mié., mar. 4

8:10 pm - 2:19 pm

YXU

SEA

21h 09m1 stop

3:10 pm - 6:35 am

SEA

YXU

12h 25m1 stop

$530WestJet

lun., mar. 2 - mié., mar. 4

8:10 pm - 2:19 pm

YXU

SEA

21h 09m1 stop

3:10 pm - 6:35 am

SEA

YXU

12h 25m1 stop

$532WestJet

lun., mar. 2 - mié., mar. 4

9:25 am - 7:16 pm

YXU

SEA

12h 51m2 stops

5:50 am - 9:21 pm

SEA

YXU

12h 31m2 stops

$543Air Canada

lun., mar. 2 - mié., mar. 4

5:40 pm - 10:16 pm

YXU

SEA

7h 36m1 stop

5:50 am - 9:21 pm

SEA

YXU

12h 31m2 stops

$562Air Canada

lun., mar. 2 - mié., mar. 4

5:40 pm - 10:16 pm

YXU

SEA

7h 36m1 stop

8:00 pm - 8:46 am

SEA

YXU

9h 46m2 stops

$563Air Canada

lun., mar. 2 - mié., mar. 4

WestJet flights from London, Ontario to Seattle

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

WestJet

Mar 2

YXU8:10 pmLondon

21h 09m

1 stop

SEA2:19 pmSeattle/Tacoma Intl

Mar 4

SEA3:10 pmSeattle/Tacoma Intl

12h 25m

1 stop

YXU6:35 amLondon

$525

Find similar

WestJet

Mar 2

YXU8:10 pmLondon

21h 09m

1 stop

SEA2:19 pmSeattle/Tacoma Intl

Mar 4

SEA3:10 pmSeattle/Tacoma Intl

12h 25m

1 stop

YXU6:35 amLondon

$530

Find similar

WestJet

Mar 2

YXU8:10 pmLondon

21h 09m

1 stop

SEA2:19 pmSeattle/Tacoma Intl

Mar 4

SEA3:10 pmSeattle/Tacoma Intl

12h 25m

1 stop

YXU6:35 amLondon

$532

Find similar

Air Canada flights from London, Ontario to Seattle

Our best Air Canada deals on London, Ontario to Seattle flight tickets

Air Canada

Mar 2

YXU5:10 amLondon

12h 51m

2 stops

SEA3:01 pmSeattle/Tacoma Intl

Mar 4

SEA5:50 amSeattle/Tacoma Intl

12h 31m

2 stops

YXU9:21 pmLondon

$529

Find similar

Air Canada

Mar 2

YXU9:25 amLondon

12h 51m

2 stops

SEA7:16 pmSeattle/Tacoma Intl

Mar 4

SEA5:50 amSeattle/Tacoma Intl

12h 31m

2 stops

YXU9:21 pmLondon

$543

Find similar

Air Canada

Mar 2

YXU5:40 pmLondon

7h 36m

1 stop

SEA10:16 pmSeattle/Tacoma Intl

Mar 4

SEA5:50 amSeattle/Tacoma Intl

12h 31m

2 stops

YXU9:21 pmLondon

$562

Find similar

Fly from

Fly to

Route

Depart

Return

Price

LondonSeattle

YXU - SEA

YXUSEA

London

lun. 3/2

8:10 pm-2:19 pm

1 stop21h 09m

Seattle/Tacoma Intl

mié. 3/4

3:10 pm-6:35 am

1 stop12h 25m

$525

LondonSeattle

YXU - SEA

YXUSEA

London

lun. 3/2

5:10 am-3:01 pm

2 stops12h 51m

Seattle/Tacoma Intl

mié. 3/4

5:50 am-9:21 pm

2 stops12h 31m

$529

LondonSeattle

YXU - SEA

YXUSEA

London

lun. 3/2

8:10 pm-2:19 pm

1 stop21h 09m

Seattle/Tacoma Intl

mié. 3/4

3:10 pm-6:35 am

1 stop12h 25m

$530

LondonSeattle

YXU - SEA

YXUSEA

London

lun. 3/2

8:10 pm-2:19 pm

1 stop21h 09m

Seattle/Tacoma Intl

mié. 3/4

3:10 pm-6:35 am

1 stop12h 25m

$532

LondonSeattle

YXU - SEA

YXUSEA

London

lun. 3/2

9:25 am-7:16 pm

2 stops12h 51m

Seattle/Tacoma Intl

mié. 3/4

5:50 am-9:21 pm

2 stops12h 31m

$543

LondonSeattle

YXU - SEA

YXUSEA

London

lun. 3/2

5:40 pm-10:16 pm

1 stop7h 36m

Seattle/Tacoma Intl

mié. 3/4

5:50 am-9:21 pm

2 stops12h 31m

$562

LondonSeattle

YXU - SEA

YXUSEA

London

lun. 3/2

5:40 pm-10:16 pm

1 stop7h 36m

Seattle/Tacoma Intl

mié. 3/4

8:00 pm-8:46 am

2 stops9h 46m

$563

LondonSeattle

YXU - SEA

YXUSEA

London

dom. 2/1

8:10 pm-2:19 pm

1 stop21h 09m

$145

LondonSeattle

YXU - SEA

YXUSEA

London

dom. 2/1

8:10 pm-10:25 am

2 stops17h 15m

$177

LondonSeattle

YXU - SEA

YXUSEA

London

dom. 2/1

8:10 pm-10:25 am

3 stops17h 15m

$196

Flights are sorted by cheapest round-trip flights first.

Sorted 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

Fastest flight time	7h 36m
Direct flights	None

The fastest flight from London, Ontario to Seattle takes 7h 36m

There are no direct flights from London, Ontario to Seattle. There are no popular flight routes from London, Ontario to Seattle.

Search flight deals

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 36m, 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.

Tacoma

Leavenworth

SeaTac

Ocean Shores

Renton

Olympia

Lynnwood

Kent

Marysville

Puyallup

Redmond

Tukwila

Cle Elum

Federal Way

Lakewood

Fife

Centralia

Westport

Kirkland

Shoreline

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.