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 62% 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$ 649 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

Last minute

Cheap round-trip flights

Enter your travel dates to find the best prices.

11:55 a.m. - 7:03 p.m.

SEA

YXU

28h 08m

2 stops

8:10 p.m. - 2:19 p.m.

YXU

SEA

21h 09m

1 stop

C$ 649WestJet

Sun, 5 Apr - Sun, 12 Apr

5:40 a.m. - 5:32 p.m.

SEA

YXU

8h 52m

2 stops

3:30 p.m. - 10:22 p.m.

YXU

SEA

9h 52m

2 stops

C$ 667Air Canada

Tue, 30 Jun - Thu, 9 Jul

5:40 a.m. - 9:18 p.m.

SEA

YXU

12h 38m

2 stops

9:25 a.m. - 7:20 p.m.

YXU

SEA

12h 55m

2 stops

C$ 684Air Canada

Fri, 3 Apr - Fri, 10 Apr

5:40 a.m. - 5:35 p.m.

SEA

YXU

8h 55m

2 stops

3:30 p.m. - 10:22 p.m.

YXU

SEA

9h 52m

2 stops

C$ 701Air Canada

Thu, 2 Jul - Thu, 9 Jul

9:55 a.m. - 8:55 a.m.

SEA

YXU

20h 00m

2 stops

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

YXU

SEA

8h 37m

1 stop

C$ 709Air Canada

Sun, 5 Jul - Mon, 13 Jul

5:40 a.m. - 9:18 p.m.

SEA

YXU

12h 38m

2 stops

9:25 a.m. - 9:53 p.m.

YXU

SEA

15h 28m

1 stop

C$ 710Air Canada

Fri, 3 Apr - Fri, 10 Apr

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

SEA

YXU

10h 40m

1 stop

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

YXU

SEA

8h 37m

1 stop

C$ 717Air Canada

Tue, 30 Jun - Thu, 9 Jul

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

SEA

YXU

10h 35m

2 stops

6:00 a.m. - 2:22 p.m.

YXU

SEA

11h 22m

2 stops

C$ 735Air Canada

Mon, 6 Jul - Fri, 10 Jul

8:00 a.m. - 9:18 p.m.

SEA

YXU

10h 18m

1 stop

9:25 a.m. - 9:53 p.m.

YXU

SEA

15h 28m

1 stop

C$ 738Air Canada

Fri, 3 Apr - Fri, 10 Apr

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

SEA

YXU

10h 35m

2 stops

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

YXU

SEA

8h 37m

1 stop

C$ 742Air Canada

Fri, 3 Jul - Mon, 13 Jul

United Airlines flights from Seattle to London, Ontario

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

United Airlines

4 Jul

SEA7:00 a.m.Seattle/Tacoma Intl

11h 40m

2 stops

YXU9:40 p.m.London

9 Jul

YXU3:30 p.m.London

8h 37m

1 stop

SEA9:07 p.m.Seattle/Tacoma Intl

C$ 776

United Airlines

3 Jul

SEA7:00 a.m.Seattle/Tacoma Intl

11h 40m

2 stops

YXU9:40 p.m.London

11 Jul

YXU6:00 a.m.London

15h 07m

2 stops

SEA6:07 p.m.Seattle/Tacoma Intl

C$ 783

United Airlines

4 Apr

SEA8:00 a.m.Seattle/Tacoma Intl

10h 18m

1 stop

YXU9:18 p.m.London

11 Apr

YXU5:10 a.m.London

21h 17m

2 stops

SEA11:27 p.m.Seattle/Tacoma Intl

C$ 879

Air Canada flights from Seattle to London, Ontario

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

Air Canada

30 Jun

SEA5:40 a.m.Seattle/Tacoma Intl

8h 52m

2 stops

YXU5:32 p.m.London

9 Jul

YXU3:30 p.m.London

9h 52m

2 stops

SEA10:22 p.m.Seattle/Tacoma Intl

C$ 667

Air Canada

3 Apr

SEA5:40 a.m.Seattle/Tacoma Intl

12h 38m

2 stops

YXU9:18 p.m.London

10 Apr

YXU9:25 a.m.London

12h 55m

2 stops

SEA7:20 p.m.Seattle/Tacoma Intl

C$ 684

Air Canada

2 Jul

SEA5:40 a.m.Seattle/Tacoma Intl

8h 55m

2 stops

YXU5:35 p.m.London

9 Jul

YXU3:30 p.m.London

9h 52m

2 stops

SEA10:22 p.m.Seattle/Tacoma Intl

C$ 701

Fly from

Fly to

Route

Depart

Return

Price

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Sun 5/4

11:55 a.m.-7:03 p.m.

2 stops28h 08m

London

Sun 12/4

8:10 p.m.-2:19 p.m.

1 stop21h 09m

C$ 649

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Tue 30/6

5:40 a.m.-5:32 p.m.

2 stops8h 52m

London

Thu 9/7

3:30 p.m.-10:22 p.m.

2 stops9h 52m

C$ 667

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Fri 3/4

5:40 a.m.-9:18 p.m.

2 stops12h 38m

London

Fri 10/4

9:25 a.m.-7:20 p.m.

2 stops12h 55m

C$ 684

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Thu 2/7

5:40 a.m.-5:35 p.m.

2 stops8h 55m

London

Thu 9/7

3:30 p.m.-10:22 p.m.

2 stops9h 52m

C$ 701

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Sun 5/7

9:55 a.m.-8:55 a.m.

2 stops20h 00m

London

Mon 13/7

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

1 stop8h 37m

C$ 709

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Fri 3/4

5:40 a.m.-9:18 p.m.

2 stops12h 38m

London

Fri 10/4

9:25 a.m.-9:53 p.m.

1 stop15h 28m

C$ 710

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Tue 30/6

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

1 stop10h 40m

London

Thu 9/7

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

1 stop8h 37m

C$ 717

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Mon 6/7

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

2 stops10h 35m

London

Fri 10/7

6:00 a.m.-2:22 p.m.

2 stops11h 22m

C$ 735

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Fri 3/4

8:00 a.m.-9:18 p.m.

1 stop10h 18m

London

Fri 10/4

9:25 a.m.-9:53 p.m.

1 stop15h 28m

C$ 738

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Fri 3/7

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

2 stops10h 35m

London

Mon 13/7

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

1 stop8h 37m

C$ 742

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 76% 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 18m
Direct flights	None

The fastest flight from Seattle to London, Ontario takes 10h 18m

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?
London is 3215.2 km away from Seattle/Tacoma Intl. A reasonable flight in good conditions will take 10h 18m.
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.