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Cheap flights from Seattle to London from $196

This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from Seattle to London departing on 8/28. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.
1 adult
1 adult, Economy, 0 bags

Find the cheapest flights from Seattle to London

Cheap round-trip flights

Enter your travel dates to find the best prices.
WestJet Logo
7:35 pm - 5:20 am
SEA
-
YXU
6h 45m
1 stop
WestJet Logo
5:55 pm - 9:00 pm
YXU
-
SEA
30h 05m
1 stop
$446WestJet
Thu, Aug 6 - Fri, Aug 14
WestJet Logo
10:30 am - 4:45 pm
SEA
-
YXU
27h 15m
1 stop
WestJet Logo
8:40 pm - 6:45 pm
YXU
-
SEA
25h 05m
1 stop
$451WestJet
Wed, Aug 5 - Fri, Aug 14
WestJet Logo
7:35 pm - 5:20 am
SEA
-
YXU
6h 45m
1 stop
WestJet Logo
5:55 pm - 9:40 am
YXU
-
SEA
18h 45m
1 stop
$492WestJet
Fri, Aug 21 - Fri, Aug 28
WestJet Logo
7:35 pm - 5:20 am
SEA
-
YXU
6h 45m
1 stop
WestJet Logo
5:55 pm - 9:40 am
YXU
-
SEA
18h 45m
1 stop
$499WestJet
Sun, Aug 23 - Sun, Aug 30
WestJet Logo
7:35 pm - 5:20 am
SEA
-
YXU
6h 45m
1 stop
WestJet Logo
5:55 pm - 9:00 pm
YXU
-
SEA
30h 05m
1 stop
$501WestJet
Mon, Aug 17 - Wed, Aug 19
WestJet Logo
10:30 am - 4:45 pm
SEA
-
YXU
27h 15m
1 stop
WestJet Logo
6:10 am - 6:45 pm
YXU
-
SEA
15h 35m
1 stop
$509WestJet
Sun, Sep 27 - Wed, Sep 30
WestJet Logo
7:00 am - 4:45 pm
SEA
-
YXU
6h 45m
1 stop
WestJet Logo
2:40 pm - 9:40 am
YXU
-
SEA
22h 00m
2 stops
$516WestJet
Fri, Aug 7 - Fri, Aug 14
WestJet Logo
7:35 pm - 4:45 pm
SEA
-
YXU
18h 10m
1 stop
WestJet Logo
5:55 pm - 6:45 pm
YXU
-
SEA
27h 50m
1 stop
$530WestJet
Mon, Aug 17 - Wed, Aug 19
Multiple Airlines Logo
8:50 pm - 7:50 pm
SEA
-
YXU
20h 00m
2 stops
Multiple Airlines Logo
8:40 pm - 9:40 am
YXU
-
SEA
16h 00m
1 stop
$558Multiple Airlines
Thu, Aug 6 - Fri, Aug 14
Multiple Airlines Logo
8:05 am - 7:15 pm
SEA
-
YXU
8h 10m
1 stop
Multiple Airlines Logo
8:00 pm - 1:20 pm
YXU
-
SEA
20h 20m
1 stop
$563Multiple Airlines
Fri, Oct 30 - Sun, Nov 8

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WestJet flights from Seattle to London, Ontario

Our best WestJet deals on Seattle to London, Ontario flight tickets
WestJet
Aug 6
SEA7:35 pmSeattle/Tacoma Intl
6h 45m
1 stop
YXU5:20 amLondon
Aug 14
YXU5:55 pmLondon
30h 05m
1 stop
SEA9:00 pmSeattle/Tacoma Intl
$446
WestJet
Aug 5
SEA10:30 amSeattle/Tacoma Intl
27h 15m
1 stop
YXU4:45 pmLondon
Aug 14
YXU8:40 pmLondon
25h 05m
1 stop
SEA6:45 pmSeattle/Tacoma Intl
$451
WestJet
Aug 21
SEA7:35 pmSeattle/Tacoma Intl
6h 45m
1 stop
YXU5:20 amLondon
Aug 28
YXU5:55 pmLondon
18h 45m
1 stop
SEA9:40 amSeattle/Tacoma Intl
$492

Air Canada flights from Seattle to London, Ontario

Our best Air Canada deals on Seattle to London, Ontario flight tickets
Air Canada
Sep 27
SEA8:00 amSeattle/Tacoma Intl
6h 43m
1 stop
YXU5:43 pmLondon
Sep 30
YXU10:05 amLondon
11h 27m
2 stops
SEA6:32 pmSeattle/Tacoma Intl
$628
Air Canada
Sep 27
SEA7:20 pmSeattle/Tacoma Intl
11h 00m
2 stops
YXU9:20 amLondon
Sep 30
YXU10:05 amLondon
11h 27m
2 stops
SEA6:32 pmSeattle/Tacoma Intl
$633
Air Canada
Aug 5
SEA8:00 amSeattle/Tacoma Intl
6h 42m
1 stop
YXU5:42 pmLondon
Aug 10
YXU6:20 pmLondon
18h 45m
2 stops
SEA10:05 amSeattle/Tacoma Intl
$646

momondo Fare Finder

 
Customize your flight search to find flights from Seattle to London, Ontario that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, momondo users made 832,500 searches. Data last updated July 12, 2026.
Use the filters below to find and compare flights from Seattle to London, Ontario that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Thu 8/6

7:35 pm-5:20 am

1 stop6h 45m

London

Fri 8/14

5:55 pm-9:00 pm

1 stop30h 05m

$446

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Wed 8/5

10:30 am-4:45 pm

1 stop27h 15m

London

Fri 8/14

8:40 pm-6:45 pm

1 stop25h 05m

$451
Quickest round-trip

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Fri 8/21

7:35 pm-5:20 am

1 stop6h 45m

London

Fri 8/28

5:55 pm-9:40 am

1 stop18h 45m

$492

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Sun 8/23

7:35 pm-5:20 am

1 stop6h 45m

London

Sun 8/30

5:55 pm-9:40 am

1 stop18h 45m

$499

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Mon 8/17

7:35 pm-5:20 am

1 stop6h 45m

London

Wed 8/19

5:55 pm-9:00 pm

1 stop30h 05m

$501

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Sun 9/27

10:30 am-4:45 pm

1 stop27h 15m

London

Wed 9/30

6:10 am-6:45 pm

1 stop15h 35m

$509

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Fri 8/7

7:00 am-4:45 pm

1 stop6h 45m

London

Fri 8/14

2:40 pm-9:40 am

2 stops22h 00m

$516

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Mon 8/17

7:35 pm-4:45 pm

1 stop18h 10m

London

Wed 8/19

5:55 pm-6:45 pm

1 stop27h 50m

$530

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Thu 8/6

8:50 pm-7:50 pm

2 stops20h 00m

London

Fri 8/14

8:40 pm-9:40 am

1 stop16h 00m

$558

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Fri 10/30

8:05 am-7:15 pm

1 stop8h 10m

London

Sun 11/8

8:00 pm-1:20 pm

1 stop20h 20m

$563

Flights are sorted by cheapest round-trip flights first.

Showing 1-10 of 19 resultsSorted by cheapest first
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See travel insights to London from

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

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

You could potentially save up to 30% 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

6h 42m

Direct flights

None
The fastest flight from Seattle to London, Ontario takes 6h 42m
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?

    The straight-line distance from Seattle/Tacoma Intl to London is 1997.9 mi. By plane, this route typically takes 6h 42m.

  • 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?

    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.

Traveling to a place near London?

Book flights to London if you plan to visit one of these locations
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 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.

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

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.

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

Yes. momondo can track prices for Seattle to London flights and alert you when they change. Perform a search to set up the price alert. All that is required is a valid email address.

An easier way to manage your London, Ontario trip

We make it super easy to schedule, organize and travel with friends or family. Trips is free — and available to use no matter where you book.
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