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

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

Which airlines fly to London, Ontario?

Alaska Airlines, WestJet and Air Canada 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 45% of people opting to fly with this airline when travelling to London, Ontario. Keep in mind that there are 3 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 old do you have to be to fly from Seattle/Tacoma Intl Airport to London Airport?

Although the minimum age for a child to fly alone is five, airlines that offer an unaccompanied minor (UMNR) service may have their own age limits, which could be impacted by factors such as flight length, 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 required for your trip to London Airport can vary based on your itinerary and personal situation. As a rule, consider having multiple documents such as a national ID card or driver’s license, and a passport valid for six-months after you plan to arrive at London Airport. We always recommend checking with your airline or a trusted third party such as IATA to get advice.

C$ 275 Cheap Flights from Seattle to London, Ontario in 2026

Find the cheapest flights from Seattle to London

Round-trip

One-way

Cheap round-trip flights

Enter your travel dates to find the best prices.

7:35 p.m. - 5:20 a.m.

SEA

YXU

6h 45m

1 stop

6:10 a.m. - 6:45 p.m.

YXU

SEA

15h 35m

1 stop

C$ 598WestJet

Sat, 15 Aug - Sat, 29 Aug

7:00 a.m. - 4:45 p.m.

SEA

YXU

6h 45m

1 stop

6:10 a.m. - 9:00 p.m.

YXU

SEA

17h 50m

1 stop

C$ 621WestJet

Sat, 15 Aug - Sat, 29 Aug

7:00 a.m. - 1:50 p.m.

SEA

YXU

27h 50m

2 stops

6:10 a.m. - 9:00 p.m.

YXU

SEA

17h 50m

1 stop

C$ 698WestJet

Sat, 15 Aug - Sat, 29 Aug

7:35 p.m. - 5:20 a.m.

SEA

YXU

6h 45m

1 stop

5:55 p.m. - 9:00 p.m.

YXU

SEA

30h 05m

1 stop

C$ 704WestJet

Mon, 17 Aug - Wed, 19 Aug

8:00 a.m. - 5:42 p.m.

SEA

YXU

6h 42m

1 stop

5:40 a.m. - 2:22 p.m.

YXU

SEA

11h 42m

2 stops

C$ 882Air Canada

Mon, 17 Aug - Wed, 19 Aug

8:00 a.m. - 5:42 p.m.

SEA

YXU

6h 42m

1 stop

5:40 a.m. - 2:22 p.m.

YXU

SEA

11h 42m

2 stops

C$ 898Air Canada

Mon, 17 Aug - Wed, 19 Aug

7:20 p.m. - 9:20 a.m.

SEA

YXU

11h 00m

2 stops

3:30 p.m. - 10:42 p.m.

YXU

SEA

10h 12m

2 stops

C$ 990Air Canada

Mon, 17 Aug - Wed, 19 Aug

7:20 p.m. - 9:20 a.m.

SEA

YXU

11h 00m

2 stops

3:30 p.m. - 10:42 p.m.

YXU

SEA

10h 12m

2 stops

C$ 1,006Air Canada

Mon, 17 Aug - Wed, 19 Aug

8:00 a.m. - 5:42 p.m.

SEA

YXU

6h 42m

1 stop

3:30 p.m. - 9:07 p.m.

YXU

SEA

8h 37m

1 stop

C$ 1,017Air Canada

Mon, 17 Aug - Wed, 19 Aug

8:00 a.m. - 5:42 p.m.

SEA

YXU

6h 42m

1 stop

5:40 a.m. - 2:22 p.m.

YXU

SEA

11h 42m

2 stops

C$ 1,024Air Canada

Mon, 17 Aug - Wed, 19 Aug

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WestJet flights from Seattle to London, Ontario

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

WestJet

15 Aug

SEA7:35 p.m.Seattle/Tacoma Intl

6h 45m

1 stop

YXU5:20 a.m.London

29 Aug

YXU6:10 a.m.London

15h 35m

1 stop

SEA6:45 p.m.Seattle/Tacoma Intl

C$ 598

WestJet

15 Aug

SEA7:00 a.m.Seattle/Tacoma Intl

6h 45m

1 stop

YXU4:45 p.m.London

29 Aug

YXU6:10 a.m.London

17h 50m

1 stop

SEA9:00 p.m.Seattle/Tacoma Intl

C$ 621

WestJet

15 Aug

SEA7:00 a.m.Seattle/Tacoma Intl

27h 50m

2 stops

YXU1:50 p.m.London

29 Aug

YXU6:10 a.m.London

17h 50m

1 stop

SEA9:00 p.m.Seattle/Tacoma Intl

C$ 698

Air Canada flights from Seattle to London, Ontario

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

Air Canada

17 Aug

SEA8:00 a.m.Seattle/Tacoma Intl

6h 42m

1 stop

YXU5:42 p.m.London

19 Aug

YXU5:40 a.m.London

11h 42m

2 stops

SEA2:22 p.m.Seattle/Tacoma Intl

C$ 882

Air Canada

17 Aug

SEA8:00 a.m.Seattle/Tacoma Intl

6h 42m

1 stop

YXU5:42 p.m.London

19 Aug

YXU5:40 a.m.London

11h 42m

2 stops

SEA2:22 p.m.Seattle/Tacoma Intl

C$ 898

Air Canada

17 Aug

SEA7:20 p.m.Seattle/Tacoma Intl

11h 00m

2 stops

YXU9:20 a.m.London

19 Aug

YXU3:30 p.m.London

10h 12m

2 stops

SEA10:42 p.m.Seattle/Tacoma Intl

C$ 990

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Sat 15/8

7:35 p.m.-5:20 a.m.

1 stop6h 45m

London

Sat 29/8

6:10 a.m.-6:45 p.m.

1 stop15h 35m

C$ 598

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Sat 15/8

7:00 a.m.-4:45 p.m.

1 stop6h 45m

London

Sat 29/8

6:10 a.m.-9:00 p.m.

1 stop17h 50m

C$ 621

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Sat 15/8

7:00 a.m.-1:50 p.m.

2 stops27h 50m

London

Sat 29/8

6:10 a.m.-9:00 p.m.

1 stop17h 50m

C$ 698

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Mon 17/8

7:35 p.m.-5:20 a.m.

1 stop6h 45m

London

Wed 19/8

5:55 p.m.-9:00 p.m.

1 stop30h 05m

C$ 704

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Mon 17/8

8:00 a.m.-5:42 p.m.

1 stop6h 42m

London

Wed 19/8

5:40 a.m.-2:22 p.m.

2 stops11h 42m

C$ 882

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Mon 17/8

8:00 a.m.-5:42 p.m.

1 stop6h 42m

London

Wed 19/8

5:40 a.m.-2:22 p.m.

2 stops11h 42m

C$ 898

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Mon 17/8

7:20 p.m.-9:20 a.m.

2 stops11h 00m

London

Wed 19/8

3:30 p.m.-10:42 p.m.

2 stops10h 12m

C$ 990

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Mon 17/8

7:20 p.m.-9:20 a.m.

2 stops11h 00m

London

Wed 19/8

3:30 p.m.-10:42 p.m.

2 stops10h 12m

C$ 1,006

Quickest round-trip

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Mon 17/8

8:00 a.m.-5:42 p.m.

1 stop6h 42m

London

Wed 19/8

3:30 p.m.-9:07 p.m.

1 stop8h 37m

C$ 1,017

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Mon 17/8

8:00 a.m.-5:42 p.m.

1 stop6h 42m

London

Wed 19/8

5:40 a.m.-2:22 p.m.

2 stops11h 42m

C$ 1,024

Flights are sorted by cheapest round-trip flights first.

Showing 1-10 of 16 resultsSorted 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 59% 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	10h 12m
Direct flights	None

The fastest flight from Seattle to London, Ontario takes 10h 12m

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

Search flight deals

Frequently asked questions about flying from Seattle to London, Ontario

How far is Seattle/Tacoma Intl to London by plane?
London is 3215.2 km away from Seattle/Tacoma Intl. A reasonable flight in good conditions will take 10h 12m.
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 old do you have to be to fly from Seattle/Tacoma Intl Airport to London Airport?
Although the minimum age for a child to fly alone is five, airlines that offer an unaccompanied minor (UMNR) service may have their own age limits, which could be impacted by factors such as flight length, 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 required for your trip to London Airport can vary based on your itinerary and personal situation. As a rule, consider having multiple documents such as a national ID card or driver’s license, and a passport valid for six-months after you plan to arrive at London Airport. We always recommend checking with your airline or a trusted third party such as IATA to get advice.

Grand Bend

Port Stanley

Why use momondo?

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 recognizable 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?

All flight searches from Seattle to London on momondo can be filtered to show those which offer flexible booking policies.

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

Once you have performed a search for Seattle to London flights, momondo helps you find the right one by offering useful filters to narrow down your flight selection. Flights can be filtered by multiple factors such as airline, airport and price; but also by other criteria like aircraft type and payment method.

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

Price alerts on flights to London from Seattle are quick and easy to set up on momondo. Simply perform a search and select the price alert feature. It is as simple as that.