What airlines fly to London, Ontario?

Alaska Airlines, Air Canada and WestJet are the top three most popular airlines that fly to London, Ontario from Seattle according to our data. Alaska Airlines is the first choice among our users, with 60% of people opting to fly with this airline when traveling to London, Ontario. Keep in mind that there are 5 different airlines that fly to London, Ontario on a routine basis, so you have a few additional options to choose from.

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

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

How many operators does momondo search for flights from Seattle/Tacoma Intl Airport to London Airport?

There is 1 operator available for flights from Seattle/Tacoma Intl Airport to London Airport as of January 2026.

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

The minimum age for a child to fly alone is five, but airlines offering an unaccompanied minor (UNMR) service may have their age restrictions, such as regulations concerning flight duration, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Seattle/Tacoma Intl Airport to London Airport.

What documentation or ID do you need to fly to London Airport?

The travel and health documents you'll need for your trip to London Airport may differ based on your itinerary and personal situation. Typically, you should have several documents on hand, such as a national ID card or driver's license and a passport that is valid for six months after your intended arrival at London Airport. It is always advisable to seek advice from your airline or a trusted third party, such as IATA.

$277 Cheap Flights from Seattle to London in 2026

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Find the cheapest flights from Seattle to London

Round-trip

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Cheap round-trip flights

Enter your travel dates to find the best prices.

8:00 pm - 8:46 am

SEA

YXU

9h 46m2 stops

5:40 pm - 10:16 pm

YXU

SEA

7h 36m1 stop

$277Air Canada

Thu, Jan 29 - Sun, Feb 1

8:00 pm - 8:46 am

SEA

YXU

9h 46m2 stops

5:10 am - 2:31 pm

YXU

SEA

12h 21m2 stops

$282Air Canada

Thu, Jan 29 - Sun, Feb 1

8:10 am - 9:21 pm

SEA

YXU

10h 11m1 stop

5:40 pm - 10:16 pm

YXU

SEA

7h 36m1 stop

$296Air Canada

Thu, Jan 29 - Sun, Feb 1

8:00 pm - 8:46 am

SEA

YXU

9h 46m2 stops

5:10 am - 7:16 pm

YXU

SEA

17h 06m2 stops

$301Air Canada

Thu, Jan 29 - Sun, Feb 1

8:10 am - 9:21 pm

SEA

YXU

10h 11m1 stop

9:25 am - 10:16 pm

YXU

SEA

15h 51m1 stop

$320Air Canada

Tue, Feb 10 - Fri, Feb 13

9:00 am - 8:46 am

SEA

YXU

20h 46m2 stops

5:40 pm - 10:16 pm

YXU

SEA

7h 36m1 stop

$367United Airlines

Wed, Feb 4 - Wed, Feb 11

8:10 am - 9:20 pm

SEA

YXU

10h 10m1 stop

5:40 pm - 10:16 pm

YXU

SEA

7h 36m1 stop

$382United Airlines

Wed, Feb 4 - Wed, Feb 11

11:59 pm - 5:05 pm

SEA

YXU

14h 06m2 stops

9:25 am - 8:56 pm

YXU

SEA

14h 31m2 stops

$383United Airlines

Fri, Feb 20 - Fri, Feb 27

12:57 pm - 5:05 pm

SEA

YXU

25h 08m3 stops

5:10 am - 4:01 pm

YXU

SEA

13h 51m2 stops

$388United Airlines

Thu, Jan 29 - Sun, Feb 1

7:00 am - 9:20 pm

SEA

YXU

11h 20m2 stops

9:25 am - 9:15 pm

YXU

SEA

14h 50m2 stops

$407United Airlines

Wed, Feb 4 - Wed, Feb 11

Air Canada flights from Seattle to London, Ontario

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

Air Canada

Jan 29

SEA8:00 pmSeattle/Tacoma Intl

9h 46m

2 stops

YXU8:46 amLondon

Feb 1

YXU5:40 pmLondon

7h 36m

1 stop

SEA10:16 pmSeattle/Tacoma Intl

$277

Air Canada

Jan 29

SEA8:00 pmSeattle/Tacoma Intl

9h 46m

2 stops

YXU8:46 amLondon

Feb 1

YXU5:10 amLondon

12h 21m

2 stops

SEA2:31 pmSeattle/Tacoma Intl

$282

Air Canada

Jan 29

SEA8:10 amSeattle/Tacoma Intl

10h 11m

1 stop

YXU9:21 pmLondon

Feb 1

YXU5:40 pmLondon

7h 36m

1 stop

SEA10:16 pmSeattle/Tacoma Intl

$296

United Airlines flights from Seattle to London, Ontario

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

United Airlines

Feb 4

SEA9:00 amSeattle/Tacoma Intl

20h 46m

2 stops

YXU8:46 amLondon

Feb 11

YXU5:40 pmLondon

7h 36m

1 stop

SEA10:16 pmSeattle/Tacoma Intl

$367

United Airlines

Feb 4

SEA8:10 amSeattle/Tacoma Intl

10h 10m

1 stop

YXU9:20 pmLondon

Feb 11

YXU5:40 pmLondon

7h 36m

1 stop

SEA10:16 pmSeattle/Tacoma Intl

$382

United Airlines

Feb 20

SEA11:59 pmSeattle/Tacoma Intl

14h 06m

2 stops

YXU5:05 pmLondon

Feb 27

YXU9:25 amLondon

14h 31m

2 stops

SEA8:56 pmSeattle/Tacoma Intl

$383

Fly from

Fly to

Route

Depart

Return

Price

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Thu 1/29

8:00 pm-8:46 am

2 stops9h 46m

London

Sun 2/1

5:40 pm-10:16 pm

1 stop7h 36m

$277

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Thu 1/29

8:00 pm-8:46 am

2 stops9h 46m

London

Sun 2/1

5:10 am-2:31 pm

2 stops12h 21m

$282

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Thu 1/29

8:10 am-9:21 pm

1 stop10h 11m

London

Sun 2/1

5:40 pm-10:16 pm

1 stop7h 36m

$296

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Thu 1/29

8:00 pm-8:46 am

2 stops9h 46m

London

Sun 2/1

5:10 am-7:16 pm

2 stops17h 06m

$301

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Tue 2/10

8:10 am-9:21 pm

1 stop10h 11m

London

Fri 2/13

9:25 am-10:16 pm

1 stop15h 51m

$320

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Wed 2/4

9:00 am-8:46 am

2 stops20h 46m

London

Wed 2/11

5:40 pm-10:16 pm

1 stop7h 36m

$367

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Wed 2/4

8:10 am-9:20 pm

1 stop10h 10m

London

Wed 2/11

5:40 pm-10:16 pm

1 stop7h 36m

$382

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Fri 2/20

11:59 pm-5:05 pm

2 stops14h 06m

London

Fri 2/27

9:25 am-8:56 pm

2 stops14h 31m

$383

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Thu 1/29

12:57 pm-5:05 pm

3 stops25h 08m

London

Sun 2/1

5:10 am-4:01 pm

2 stops13h 51m

$388

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Wed 2/4

7:00 am-9:20 pm

2 stops11h 20m

London

Wed 2/11

9:25 am-9:15 pm

2 stops14h 50m

$407

Flights are sorted by cheapest round-trip flights first.

Sorted by cheapest first

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

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

Can stopping save me money on Seattle to London, Ontario flights?

You could potentially save up to 49% on your flight if you consider stops on a Seattle to London, Ontario flight.

When to book flights from Seattle to London, Ontario

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

Estimated round-trip price

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

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

Fastest flight time	9h 05m
Direct flights	None

The fastest flight from Seattle to London, Ontario takes 9h 05m

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

Search flight deals

How far is Seattle/Tacoma Intl to London by plane?
The straight-line distance from Seattle/Tacoma Intl to London is 1997.9 mi. By plane, this route typically takes 9h 05m.
When did momondo last update prices for flights from Seattle/Tacoma Intl Airport to London Airport?
Prices for flights from Seattle/Tacoma Intl Airport to London Airport are updated daily.
How many operators does momondo search for flights from Seattle/Tacoma Intl Airport to London Airport?
There is 1 operator available for flights from Seattle/Tacoma Intl Airport to London Airport as of January 2026.
How old do you have to be to fly from Seattle/Tacoma Intl Airport to London Airport?
The minimum age for a child to fly alone is five, but airlines offering an unaccompanied minor (UNMR) service may have their age restrictions, such as regulations concerning flight duration, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Seattle/Tacoma Intl Airport to London Airport.
What documentation or ID do you need to fly to London Airport?
The travel and health documents you'll need for your trip to London Airport may differ based on your itinerary and personal situation. Typically, you should have several documents on hand, such as a national ID card or driver's license and a passport that is valid for six months after your intended arrival at London Airport. It is always advisable to seek advice from your airline or a trusted third party, such as IATA.
What is the most popular airline from Seattle to London, Ontario?
Based on momondo bookings for this flight route, the most popular airline on flight routes from Seattle to London, Ontario is Air Canada (100% of total bookings).

Best airlines flying from Seattle to London, Ontario

Compare and see reviews for airlines that fly from Seattle to London, Ontario with momondo

Airline	Rating	Free Cancellation	Price
Air Canada	PriceFrom $460	Free Cancellation	Rating 7.1 10,603 reviews		Search Air Canada flights

Grand Bend

Port Stanley

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

Finding the right flight to London from Seattle is quick and easy when you have a range of options in front of you, from reputable agents and recognisable airlines. Options that can then be filtered down to find the best fit. That is what momondo does. We make finding flights to London quick and easy, saving you time and money.

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

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

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momondo offers useful filters to help you find the right flight. Choose specific flight times, airports or even what payment method you prefer. We have numerous options to help you book your ideal flight from Seattle to London.

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