YXU - SEA

C$ 356 Find Cheap Flights from London to Seattle

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from London to Seattle departing on 14/7. 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 Seattle

 
These are the airlines KAYAK users have selected most often from within our search results in flight searches from London to Seattle, 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 London to Seattle, as well as popular online travel agencies
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Everything you should know

Cheapest round-trip
C$ 520
WestJet
Wed 6/5Sat 9/5
YXU - SEA • 1 stop
Cheapest one-way flights
C$ 356
Air Canada
Tue 14/7
YXU - SEA • 1 stop
Top airlines
Cheapest • from C$ 520 (round-trip)
Best reviews • 7.4 score
Airline reviews
Airline reviews
+1
+1
Airline reviews
Airline reviews
+1
Direct flights
Not available
There are currently no direct flights between London and Seattle. You’ll need at least 1 connection.
Insights
Insights
Insights
Insights
Top layover airports
Cheapest • Avg C$ 291 (round-trip)
Shortest trip • 7h 25m (one-way)
Insights
Insights
Insights
Insights
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KAYAK searches hundreds of sites at once to find you the best travel deals.
We hope you love your trip to Seattle!
Flight Deals
Booking Insights
Flight Deals

Cheap Flights from London to Seattle (YXU-SEA)

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from London to Seattle 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 London to Seattle

Wed, 6 May - Sat, 9 May
WestJet Logo
6:10 a.m. - 6:45 p.m.
YXU
-
SEA
15h 35m
1 stop
WestJet Logo
7:35 p.m. - 5:20 a.m.
SEA
-
YXU
6h 45m
1 stop
C$ 520WestJet
Wed, 6 May - Sat, 9 May
WestJet Logo
5:55 p.m. - 9:40 a.m.
YXU
-
SEA
18h 45m
1 stop
WestJet Logo
7:35 p.m. - 5:20 a.m.
SEA
-
YXU
6h 45m
1 stop
C$ 531WestJet
Tue, 9 Jun - Sat, 13 Jun
WestJet Logo
6:10 a.m. - 6:45 p.m.
YXU
-
SEA
15h 35m
1 stop
WestJet Logo
7:35 p.m. - 5:20 a.m.
SEA
-
YXU
6h 45m
1 stop
C$ 543WestJet
Wed, 6 May - Sat, 9 May
WestJet Logo
6:10 a.m. - 6:45 p.m.
YXU
-
SEA
15h 35m
1 stop
WestJet Logo
7:35 p.m. - 5:20 a.m.
SEA
-
YXU
6h 45m
1 stop
C$ 597WestJet
Sat, 30 May - Sat, 6 Jun
WestJet Logo
5:55 p.m. - 9:40 a.m.
YXU
-
SEA
18h 45m
1 stop
WestJet Logo
10:30 a.m. - 5:20 a.m.
SEA
-
YXU
15h 50m
1 stop
C$ 648WestJet
Wed, 6 May - Sat, 9 May
WestJet Logo
5:55 p.m. - 6:45 p.m.
YXU
-
SEA
27h 50m
1 stop
WestJet Logo
7:35 p.m. - 4:45 p.m.
SEA
-
YXU
18h 10m
1 stop
C$ 655WestJet
Tue, 9 Jun - Sat, 13 Jun
WestJet Logo
2:40 p.m. - 9:40 a.m.
YXU
-
SEA
22h 00m
2 stops
WestJet Logo
7:35 p.m. - 5:20 a.m.
SEA
-
YXU
6h 45m
1 stop
C$ 684WestJet
Sat, 30 May - Sat, 6 Jun
WestJet Logo
5:55 p.m. - 9:40 a.m.
YXU
-
SEA
18h 45m
1 stop
WestJet Logo
10:30 a.m. - 1:50 p.m.
SEA
-
YXU
24h 20m
2 stops
C$ 702WestJet
Wed, 6 May - Sat, 9 May
Delta Logo
6:10 a.m. - 5:16 p.m.
YXU
-
SEA
14h 06m
2 stops
Delta Logo
7:35 p.m. - 5:20 a.m.
SEA
-
YXU
6h 45m
1 stop
C$ 731Delta
Sat, 30 May - Sat, 6 Jun
United Airlines Logo
5:10 a.m. - 8:53 p.m.
YXU
-
SEA
18h 43m
2 stops
United Airlines Logo
10:40 p.m. - 2:58 p.m.
SEA
-
YXU
13h 18m
2 stops
C$ 761United Airlines
Booking Insights

KAYAK's insights & trends for London to Seattle flights

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

Which airlines provide the cheapest flights from London to Seattle?

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 London to Seattle were found on WestJet (C$ 520) and Delta (C$ 730).

Good to know

Cheapest flightC$ 356
Flight from London to Seattle

When to book flights from London to Seattle

Are your dates flexible? Find out the best times to travel from London to Seattle 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 London to Seattle

  • What is the cheapest flight from London to Seattle?

    In the last 3 days, the lowest price for a flight from London to Seattle was C$ 356 for a one-way ticket and C$ 520 for a round-trip.

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

    London airport is called London and the only airport in Seattle is Seattle/Tacoma Intl.

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

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

  • Which airline alliances offer flights from London to Seattle?

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

  • Which is the best airline for flights from London to Seattle, United Airlines or WestJet?

    The two airlines most popular with KAYAK users for flights from London to Seattle are United Airlines and WestJet. With an average price for the route of C$ 294 and an overall rating of 7.4, United Airlines is the most popular choice. WestJet is also a great choice for the route, with an average price of C$ 413 and an overall rating of 7.2.

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

    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 London to Seattle.

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

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Seattle from London 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 London to Seattle?

    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 Seattle with an airline and back to London with another airline.

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

    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 Seattle from London up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

Reviews of the top 3 airlines flying from London to Seattle

 
See real verified KAYAK customer reviews for airlines flying from London to Seattle. 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 London to Seattle? 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.
7.4
United AirlinesOverall score based on 9596 reviews
6.6Food
7.1Entertainment
7.7Boarding
8.1Crew
7.3Comfort
Airline reviews

They were fast and I like how they used to entertainment system to play video about the safety.

10.0 ExcellentAnonymous, Apr 2026
YYC - DEN
Read more United Airlines reviews

They were fast and I like how they used to entertainment system to play video about the safety.

Smooth and easy boarding, comfortable for the entire 5 hour flight, and the seat back entertainment was great! I appreciated all the features, from location info and maps, movies, the ability to connect with Bluetooth headphones, and good selection of movies. Food was good, normal airline snacks (I didn’t purchase anything)

Hopped on time for the flight only to get deplaned and delayed another 2.5 hours.

Given I (and I’m assuming most people) have both carry in and a personal item included in their fare, I find it very unfair that on neither of my flights I was able to use the overhead for my small backpack because they were completely rammed with luggage, people personal items, jackets, hats and other items. So the only item I brought in had to be stuffed under my seat while they had their leg room and sat comfortable with all of their items in the overhead. This has to stop because I was uncomfortable on both flights when I only had one smaller item that could not be checked due to its contents (medication etc). Plenty of people could have checked theirs but chose not to and then took up the space allotment for 2 people.

Flight attendants had a little attitude. Food tastes no good.

From pre boarding to flight attendant, crew and baggage handler, excellent. Didn’t lost my luggage like West jet.

Very poor. The flight was delayed from Toronto because some forget to do there job . I got to my connecting gate in San Francisco 10 minutes before the departure.but this didn’t let me board even though the flight was still there for an other 30 minutes. The the gentleman at the unite airline desk told me that they usually wait for passengers but air Canada called and told them not to we I been rerouted to Manila instead of Hong Kong . In San Francisco they mad me check in my carryon bag . I was told the it will directly go yo ho chi minn cuyt but I was told that by the Vietnams airline desk that’s not there I’m 10 hours behind my scheduled flight and looks like I I’m going without baggage. I don’t have a chance of catching ..

It was great. There were some issues prior to takeoff. The weather was poor so we had to go through deicing, and we were delayed a bit by the pilots' concern about one of the engines, but that's aviation. The pilots handled everything with aplomb, and kept us apprised

Reliable, nice crew, I fly often on that flight and I like it all.

l really enjoy very much the flight was very pleasant

The flight didn’t happen because they apparently lost my check in and wouldn’t let me board.

Access to movies was rather confusing. Apart from that, I have no complaints.

The agents at the Kelowna YLW airport were really grumpy. Same with oversized baggage person. Staff on the plane were great.

As someone who never flies WestJet unless there is no other viable option I have to give this crew credit where credit is due. Extremely well done everyone.

Flight left on time. The crew was very friendly. I had to buy a proper meal. Small cookie and a drink just doesn’t cut it for a 4.5 hours flight.

Experience was good, the wifi hook up is somewhat tough

I will not be flying with westjet again. I was uncomfortable in my seat. The position made my back hurt so bad. My wife was able to fit the seatbelt around her with out an extension but was unable to put the tray table down or fit in the seat for that matter. Our bag was smashed and I spent two hours trying to fill out the application for a damaged bag before I gave up. The 80 photos I took would not work and nothing telling me the format to upload them as.. I made the mistake of unpacking the bag before taking photos so no claim for me. Next trip to Canada I will have to use air Canada.

They lost my bag. Hopefully it will be here tomorrow.

My luggage was damaged 1 wheel was out I can't find it nowhere

Took 3 hours to check in and drop off our suitcases. Half of the passengers were still in line by boarding time. The computer systems and staff were very slow. Staff were also disorganized and kept allowing later flights to skip lines. Suitcases were piling on that several other passengers didn't get their suitcases. Then, we were sitting in the plane for 2 hours and were told that the flight was overbooked. We missed our connecting flight and had to fly the following day but with a stop over. Good thing ONE WestJet customer rep was pleasant and actually knew how to do her job when we wanted to rebook to a direct flight. Thank you to Kim at Toronto airport. Terrible experience at PUJ. Won't go back to Dominican Republic.

The seat design in the premium economy section leaves virtually no room under the seat to store a bag or purse. Other than that, it was a great flight. Arrived early.

The flight was delayed, but not for weather. We landed over 3hrs later than planned.

The stag were helpful, kind and liked the passengers. The plane was pristinely clean! Great flight!

My flight was delayed more than once, but Air Canada updated us regularly. Friends on other airlines had much worse experiences.

Got denied my flight was told on Google that Air Canada was supposed to book me a flight back home because I never was able to go to my destination. They did not help me whatsoever. I had to book a whole new flight for that reason I would write this is zero

Terrible…. Reported missing luggage’s with injectable meds that needed refrigeration. Yet, delivery could not be expedited. Luggage’s were delivered 5 days after arrival. The meds were useless as ice pack had melted. So disappointed!!!

My seat was covered in vomit and I will be reaching out to Air Canada

It's kindof ridiculous that your system is even asking me about this since my flight was canceled and I wasn't rescheduled.

3 hr delay at the gate while they were doing maintenance. Next time, do not board passengers while maintenance is being performed

Digital check in is very poor with air canada compaired to other airlines

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

Information on your arrival and departure airports