SEA - YXU

$349 Find Cheap Flights from Seattle to London

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from Seattle to London departing on 7/2. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
1 adult
1 adult, Economy, 0 bags

KAYAK searches hundreds of travel sites at once for deals on flights to London

 
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Seattle to London, as well as popular online travel agencies
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Seattle to London, as well as popular online travel agencies
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41.299.237 searches in the past 7 days on KAYAK

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Everything you should know

Cheapest round-trip
$363
Air Canada
Wed 2/11Sun 2/15
SEA - YXU • 2 stops
Cheapest one-way
$349
WestJet
Thu 7/2
SEA - YXU • 1 stop
Top airlines
Air Canada
Cheapest • from $363 (round-trip)
Air Canada
Best reviews • 7.1 score
Airline reviews
Airline reviews
+1
+1
Airline reviews
Airline reviews
+1
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Booking Insights
Flight Deals

Cheap Flights from Seattle to London (SEA-YXU)

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from Seattle to London that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.
Discover the best prices for you by selecting your travel dates on KAYAK.

Recent round-trip flight deals from Seattle to London

Wed, Feb 11 - Sun, Feb 15
Air Canada Logo
5:45 am - 8:46 am
SEA
-
YXU
24h 01m
2 stops
Air Canada Logo
5:40 pm - 10:16 pm
YXU
-
SEA
7h 36m
1 stop
$363Air Canada
Wed, Feb 11 - Sun, Feb 15
Air Canada Logo
5:45 am - 8:46 am
SEA
-
YXU
24h 01m
2 stops
Air Canada Logo
5:40 pm - 10:16 pm
YXU
-
SEA
7h 36m
1 stop
$374Air Canada
Wed, Feb 11 - Sun, Feb 15
United Airlines Logo
5:00 am - 5:05 pm
SEA
-
YXU
9h 05m
2 stops
United Airlines Logo
5:10 am - 10:43 pm
YXU
-
SEA
20h 33m
2 stops
$425United Airlines
Wed, Feb 11 - Sun, Feb 15
United Airlines Logo
5:00 am - 5:05 pm
SEA
-
YXU
9h 05m
2 stops
United Airlines Logo
9:25 am - 10:43 pm
YXU
-
SEA
16h 18m
2 stops
$436United Airlines
Thu, Mar 12 - Thu, Mar 19
Multiple Airlines Logo
8:15 am - 6:35 am
SEA
-
YXU
19h 20m
2 stops
Multiple Airlines Logo
8:10 pm - 7:51 pm
YXU
-
SEA
26h 41m
1 stop
$500Multiple Airlines
Thu, Mar 12 - Thu, Mar 19
Multiple Airlines Logo
3:10 pm - 6:35 am
SEA
-
YXU
12h 25m
1 stop
Multiple Airlines Logo
8:10 pm - 7:51 pm
YXU
-
SEA
26h 41m
1 stop
$559Multiple Airlines
Thu, Mar 12 - Thu, Mar 19
WestJet Logo
3:10 pm - 6:35 am
SEA
-
YXU
12h 25m
1 stop
WestJet Logo
8:10 pm - 10:25 am
YXU
-
SEA
17h 15m
3 stops
$599WestJet
Wed, Feb 11 - Sun, Feb 15
Air Canada Logo
8:00 am - 9:21 pm
SEA
-
YXU
10h 21m
1 stop
Air Canada Logo
5:40 pm - 10:16 pm
YXU
-
SEA
7h 36m
1 stop
$661Air Canada
Wed, Feb 11 - Sun, Feb 15
Air Canada Logo
8:00 am - 9:21 pm
SEA
-
YXU
10h 21m
1 stop
Air Canada Logo
5:40 pm - 10:16 pm
YXU
-
SEA
7h 36m
1 stop
$677Air Canada
Thu, Jul 9 - Sun, Jul 12
WestJet Logo
7:05 am - 7:07 pm
SEA
-
YXU
9h 02m
1 stop
WestJet Logo
8:00 pm - 6:38 pm
YXU
-
SEA
25h 38m
1 stop
$685WestJet
Booking Insights

KAYAK's insights & trends for Seattle to London flights

Get data-powered insights and trends into flights from Seattle to London to help you find the cheapest flights, the best time to fly and much more.

Which airlines provide the cheapest flights from Seattle to London?

The cheapest round-trip price for the route for each airline clicked by KAYAK users in the last 72 hours.

In the past 3 days, the cheapest round-trip tickets from Seattle to London were found on Air Canada ($363) and United Airlines ($425).

Good to know

Cheapest flight$349
Flight from Seattle to London

When to book flights from Seattle to London

Are your dates flexible? Find out the best times to travel from Seattle to London based on our flight data from the last year. Discover the cheapest month and even day to fly.
Estimated round-trip price
KAYAK looks at all historical flight data for each date to provide a predicted price for one-way trips or round-trips with a duration up to 40 days. While we try to provide actual minimum prices for each date, some prices are predictions and actual prices may differ.

FAQs for booking flights from Seattle to London

  • What is the cheapest flight from Seattle to London?

    In the last 3 days, the lowest price for a flight from Seattle to London was $349 for a one-way ticket and $363 for a round-trip.

  • Do I need a passport to fly between Seattle and London?

    Yes

  • Which airports will I be using when flying from Seattle to London?

    Seattle and London are both served by 1 main airport. You will leave Seattle from Seattle/Tacoma Intl and will be arriving at London.

  • Which aircraft models fly most regularly from Seattle to London?

    We unfortunately don’t have that data for this specific route.

  • Which airline alliances offer flights from Seattle to London?

    Star Alliance is the only airline alliance operating flights between Seattle and London.

  • How does KAYAK find such low prices on flights from Seattle to London?

    KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Seattle to London.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Seattle to London?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to London from Seattle is likely to change within 7 days, so travelers know whether to wait or book now.

  • What is the Hacker Fare option on flights from Seattle to London?

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to London with an airline and back to Seattle with another airline. Booking your flights between Seattle and YXU can sometimes prove cheaper using this method.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Seattle to London?

    Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to London from Seattle up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

Reviews of the top airline flying from Seattle to London

 
See real verified KAYAK customer reviews for airlines flying from Seattle to London. Airline scores are aggregated from all reviews left by passengers on KAYAK after flying with an airline. KAYAK doesn’t show reviews that are older than 5 years. Learn how KAYAK collects reviews.
Need help choosing which airline to fly with from Seattle to London? KAYAK airline reviews give an overall score for each airline based on loads of factors, including comfort, boarding, in-flight entertainment and more, to make your decision easier. See airline scores according to verified KAYAK customer reviews.
7.1
Air CanadaOverall score based on 10666 reviews
7.8Crew
7.3Boarding
7.1Comfort
6.8Entertainment
6.3Food
Airline reviews

The plane was delayed substantially due to a mechanical problem, that being said, the airline was very fair with providing a meal coupon for us. I would rather arrive late on a mechanically sound plane than the alternative. The food served in the plane was just awful, however and I recommend a new catering company.

4.0 OkayLarissa, Jan 2026
FLL - YYZ
Read more Air Canada reviews

The plane was delayed substantially due to a mechanical problem, that being said, the airline was very fair with providing a meal coupon for us. I would rather arrive late on a mechanically sound plane than the alternative. The food served in the plane was just awful, however and I recommend a new catering company.

I waiting for 2 hrs to retrieve my luggage. Didn't get home till 3am.

The flight left late and I didn’t get a glass of bubbly upon boarding (which I’m used to when booking business class on other flights), but otherwise it was a pleasant flight with lovely, helpful crew members and I enjoyed my meal.

Flight was canceled for a reason they knew hours before but did not mention. Next the gate chnage from 37 to 38 at least 10 times. Ridiculous.

It was just fine. I managed to make all my connection too sbut had trouble in Munich with no wheel chair and trouble trying to get help from the airport people to get to the other terminal for my flight. Finally a wonderful lady Amelia, helped me to make my flight connection Timon with zero time to spare.

Super experience. Earlier than schedule departure and arrival. Baggage handling was very good

I would like to get my money back. I flight was 4 hours late on the way to detroit, And same on my way back to Brussels they cancelled my flight and give me an other ticket and i had to wait 5 hours.

All attendents were very efficient, pleasant and happy. Everything went smoothly. The seats could have been wider. There could have been more free food instead of just one small bar.

My seat was one of those that couldn't recline, but the problem was that it was abnormally upright, so the headrest actually made the seat concave, which was uncomfortable and hard on my lower back. I had to ball my jacket up and use it as lumbar support. goodness I had it with me.

I liked a lot , the flight attendant so nice ,the seat very comfortable I enjoyed the flight , I will do it again with Air Canada,

Everything you need to know for your flight from Seattle to London

Information on your arrival and departure airports