Which 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 63% 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$ 641 Cheap Flights from Seattle to London in 2026

1 adult

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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. - 4:45 p.m.

SEA

YXU

18h 10m

1 stop

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

YXU

SEA

15h 35m

1 stop

C$ 641WestJet

Mon, 4 May - Wed, 6 May

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

SEA

YXU

6h 45m

1 stop

8:40 p.m. - 9:40 a.m.

YXU

SEA

16h 00m

1 stop

C$ 659WestJet

Tue, 11 Aug - Tue, 25 Aug

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

SEA

YXU

6h 45m

1 stop

2:40 p.m. - 9:00 p.m.

YXU

SEA

9h 20m

2 stops

C$ 673WestJet

Tue, 11 Aug - Tue, 25 Aug

8:00 a.m. - 5:45 p.m.

SEA

YXU

6h 45m

1 stop

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

YXU

SEA

11h 42m

2 stops

C$ 729Air Canada

Sun, 6 Sep - Sat, 26 Sep

7:20 p.m. - 8:55 a.m.

SEA

YXU

10h 35m

2 stops

3:30 p.m. - 9:04 p.m.

YXU

SEA

8h 34m

1 stop

C$ 739Air Canada

Tue, 8 Sep - Tue, 22 Sep

5:40 a.m. - 5:45 p.m.

SEA

YXU

9h 05m

2 stops

9:30 a.m. - 6:32 p.m.

YXU

SEA

12h 02m

2 stops

C$ 747Air Canada

Tue, 8 Sep - Tue, 22 Sep

10:30 a.m. - 8:55 a.m.

SEA

YXU

19h 25m

2 stops

3:25 p.m. - 10:16 p.m.

YXU

SEA

9h 51m

1 stop

C$ 765Air Canada

Fri, 9 Oct - Tue, 27 Oct

3:00 p.m. - 8:55 a.m.

SEA

YXU

14h 55m

2 stops

5:45 a.m. - 2:31 p.m.

YXU

SEA

11h 46m

2 stops

C$ 772Air Canada

Fri, 9 Oct - Fri, 30 Oct

8:00 a.m. - 9:40 p.m.

SEA

YXU

10h 40m

1 stop

3:30 p.m. - 9:04 p.m.

YXU

SEA

8h 34m

1 stop

C$ 774Air Canada

Tue, 8 Sep - Tue, 22 Sep

5:45 a.m. - 5:45 p.m.

SEA

YXU

9h 00m

2 stops

9:30 a.m. - 6:32 p.m.

YXU

SEA

12h 02m

2 stops

C$ 776Air Canada

Tue, 11 Aug - Tue, 25 Aug

Air Canada flights from Seattle to London, Ontario

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

Air Canada

6 Sep

SEA8:00 a.m.Seattle/Tacoma Intl

6h 45m

1 stop

YXU5:45 p.m.London

23 Sep

YXU3:30 p.m.London

8h 34m

1 stop

SEA9:04 p.m.Seattle/Tacoma Intl

C$ 729

Air Canada

8 Sep

SEA7:20 p.m.Seattle/Tacoma Intl

10h 35m

2 stops

YXU8:55 a.m.London

22 Sep

YXU3:30 p.m.London

8h 34m

1 stop

SEA9:04 p.m.Seattle/Tacoma Intl

C$ 739

Air Canada

8 Sep

SEA5:40 a.m.Seattle/Tacoma Intl

9h 05m

2 stops

YXU5:45 p.m.London

22 Sep

YXU9:30 a.m.London

12h 02m

2 stops

SEA6:32 p.m.Seattle/Tacoma Intl

C$ 747

WestJet flights from Seattle to London, Ontario

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

WestJet

4 May

SEA7:35 p.m.Seattle/Tacoma Intl

18h 10m

1 stop

YXU4:45 p.m.London

6 May

YXU6:10 a.m.London

15h 35m

1 stop

SEA6:45 p.m.Seattle/Tacoma Intl

C$ 641

WestJet

11 Aug

SEA7:00 a.m.Seattle/Tacoma Intl

6h 45m

1 stop

YXU4:45 p.m.London

25 Aug

YXU8:40 p.m.London

16h 00m

1 stop

SEA9:40 a.m.Seattle/Tacoma Intl

C$ 659

WestJet

11 Aug

SEA7:00 a.m.Seattle/Tacoma Intl

6h 45m

1 stop

YXU4:45 p.m.London

25 Aug

YXU2:40 p.m.London

9h 20m

2 stops

SEA9:00 p.m.Seattle/Tacoma Intl

C$ 673

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Mon 4/5

7:35 p.m.-4:45 p.m.

1 stop18h 10m

London

Wed 6/5

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

1 stop15h 35m

C$ 641

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Tue 11/8

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

1 stop6h 45m

London

Tue 25/8

8:40 p.m.-9:40 a.m.

1 stop16h 00m

C$ 659

Quickest round-trip

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Tue 11/8

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

1 stop6h 45m

London

Tue 25/8

2:40 p.m.-9:00 p.m.

2 stops9h 20m

C$ 673

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Sun 6/9

8:00 a.m.-5:45 p.m.

1 stop6h 45m

London

Sat 26/9

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

2 stops11h 42m

C$ 729

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Tue 8/9

7:20 p.m.-8:55 a.m.

2 stops10h 35m

London

Tue 22/9

3:30 p.m.-9:04 p.m.

1 stop8h 34m

C$ 739

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Tue 8/9

5:40 a.m.-5:45 p.m.

2 stops9h 05m

London

Tue 22/9

9:30 a.m.-6:32 p.m.

2 stops12h 02m

C$ 747

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Fri 9/10

10:30 a.m.-8:55 a.m.

2 stops19h 25m

London

Tue 27/10

3:25 p.m.-10:16 p.m.

1 stop9h 51m

C$ 765

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Fri 9/10

3:00 p.m.-8:55 a.m.

2 stops14h 55m

London

Fri 30/10

5:45 a.m.-2:31 p.m.

2 stops11h 46m

C$ 772

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Tue 8/9

8:00 a.m.-9:40 p.m.

1 stop10h 40m

London

Tue 22/9

3:30 p.m.-9:04 p.m.

1 stop8h 34m

C$ 774

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Tue 11/8

5:45 a.m.-5:45 p.m.

2 stops9h 00m

London

Tue 25/8

9:30 a.m.-6:32 p.m.

2 stops12h 02m

C$ 776

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 70% 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

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 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 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.