SEA - LHR

£254 Find Cheap Flights from Seattle to London Heathrow Airport

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 Heathrow departing on 12/11. 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 Heathrow Airport

 
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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Flight Deals

Cheap Flights from Seattle to Heathrow (SEA-LHR)

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for return flights from Seattle to Heathrow 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 return flight deals from Seattle to Heathrow

Sun, 15 Mar - Sun, 29 Mar
Icelandair Logo
15:35 - 19:30SEA-LHR
20h 55m1 stop
Icelandair Logo
21:25 - 17:50LHR-SEA
28h 25m1 stop
£389Icelandair
Find Deal
Tue, 25 Nov - Mon, 19 Jan
Icelandair Logo
14:35 - 19:30SEA-LHR
20h 55m1 stop
Icelandair Logo
12:15 - 17:00LHR-SEA
12h 45m1 stop
£389Icelandair
Find Deal
Thu, 13 Nov - Thu, 27 Nov
Icelandair Logo
14:35 - 10:50SEA-LHR
12h 15m1 stop
Icelandair Logo
12:15 - 17:00LHR-SEA
12h 45m1 stop
£390Icelandair
Find Deal
Wed, 28 Jan - Wed, 4 Feb
Multiple Airlines Logo
14:35 - 21:20SEA-LHR
22h 45m2 stops
Multiple Airlines Logo
06:40 - 17:00LHR-SEA
18h 20m2 stops
£407Multiple Airlines
Find Deal
Wed, 10 Dec - Wed, 17 Dec
Aer Lingus Logo
20:05 - 17:50SEA-LHR
13h 45m1 stop
Aer Lingus Logo
08:50 - 18:20LHR-SEA
17h 30m1 stop
£415Aer Lingus
Find Deal
Sun, 30 Nov - Fri, 5 Dec
Aer Lingus Logo
20:05 - 15:35SEA-LHR
11h 30m1 stop
Aer Lingus Logo
08:50 - 18:20LHR-SEA
17h 30m1 stop
£416Aer Lingus
Find Deal
Tue, 9 Dec - Tue, 16 Dec
Virgin Atlantic Logo
19:20 - 12:50SEA-LHR
9h 30mdirect
Virgin Atlantic Logo
12:20 - 14:58LHR-SEA
10h 38mdirect
£416Virgin Atlantic
Find Deal
Wed, 10 Dec - Wed, 17 Dec
Lufthansa Logo
15:40 - 11:50SEA-LHR
12h 10m1 stop
Lufthansa Logo
07:40 - 13:20LHR-SEA
13h 40m1 stop
£422Lufthansa
Find Deal
Mon, 10 Nov - Tue, 18 Nov
Lufthansa Logo
15:40 - 11:50SEA-LHR
12h 10m1 stop
Lufthansa Logo
06:35 - 19:16LHR-SEA
20h 41m2 stops
£428Lufthansa
Find Deal
Tue, 11 Nov - Tue, 18 Nov
Multiple Airlines Logo
14:35 - 15:35SEA-LHR
17h 00m2 stops
Multiple Airlines Logo
07:50 - 17:00LHR-SEA
17h 10m2 stops
£432Multiple Airlines
Find Deal

Everything you should know

Our travellers' advice
AI-generated summary based on content written by travel experts and KAYAK users
Air France offers complimentary champagne in economy.
Bring a sack lunch as airport food is expensive.
Expert advice
Expert advice
+1
+1
Expert advice
Expert advice
+1
Top airlines
Icelandair
Cheapest • from £389 (return)
Virgin Atlantic
Best reviews • 7.5 score
Airline reviews
Airline reviews
+1
+1
Airline reviews
Airline reviews
+1
When to book
3 weeks
in advance
Our data shows that travellers who book at least 3 weeks in advance save around 20% compared to booking last minute.
Insights
Insights
Insights
Insights
When to travel
March
Cheapest • 15% price drop
August
Most popular
Good to know
Good to know
+1
+1
Good to know
Good to know
+1
Cheapest return fare
£389
Overall average: £512
Icelandair
Sun 15/3Sun 29/3
SEA - LHR • 1 stop
Cheapest direct flights
£416
Typical prices: £606-£1,093
Virgin Atlantic
Tue 9/12Tue 16/12
SEA - LHR • Direct
Start a new search
KAYAK searches hundreds of sites at once to find you the best travel deals.
We hope you love your trip to Heathrow!
Booking Insights

KAYAK's insights & trends for Seattle to Heathrow flights

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

What’s the cheapest day of the week to fly from Seattle to London Heathrow Airport?

The average price of all round-trip flights from Seattle to London Heathrow Airport clicked on KAYAK for each day over the last 12 months.

For Seattle to London Heathrow Airport, Tuesday is the cheapest day to fly on average and Friday is the most expensive. Flying from London Heathrow Airport back to Seattle, the best deals are generally found on Wednesday, with Sunday being the most expensive.

What is the cheapest month to fly from Seattle to London Heathrow Airport?

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from Seattle to London Heathrow Airport, removes the top 0.1% to account for outliers, and then takes the median of all values for each month.

The cheapest month for flights from Seattle to London Heathrow Airport is March, where tickets cost £512 (return) on average. On the other hand, the most expensive months are June and December, where the average cost of round-trip tickets is £820 and £758 respectively.

Can I save money by flying with a stopover from Seattle to London Heathrow Airport?

The average return price for all direct flights, flights with one stopover, and flights with two stopovers for the route found by users searching on KAYAK in the last 2 weeks.

Yes, flying with a stopover may cost you more time, but you can also save money on the route, with a 2 stops stopover the cheapest option at £462 on average.

How far in advance should I book a flight from Seattle to London Heathrow Airport?

To calculate weekly average prices, KAYAK takes all prices for each week before departure over the last year for round-trip flights from Seattle to London Heathrow Airport, removes the top 0.1% to account for outliers, and then takes the average of all the values for each week.

To get a below average price on the flight from Seattle to London Heathrow Airport, you should book around 3 weeks before departure, which saves you about 20% compared to booking last minute. For the absolute cheapest price, our data suggests you should book 9 weeks before departure.

Expert advice

Expert advice for your flight from Seattle to Heathrow

 
Snippets provided in this section are AI-generated based on a summarisation of KAYAK-commissioned articles. The articles are presented as-is, for general informational purposes only, and may not be up-to-date. The opinions contained in the articles are original to the author and reflect their authentic experience, which may vary significantly from the experience of others.
KAYAK teamed up with top travel experts to share the best tips for your journey.
Airlines
KLM

Premium Comfort offers SkyPriority security and two checked bags, ideal for long-haul flights.


World Business Class features lay-flat seats with direct aisle access for comfort.

Read more about KLMby Blane Bachelor
Air France

Air France Premium offers SkyPriority benefits and meals by celebrity chefs on long-haul flights.


Economy includes complimentary champagne and personal entertainment screens for a luxe touch.

Finnair

Finnair's A350 offers lower cabin altitude and higher humidity for a better arrival feeling.


Economy Comfort offers extra legroom for a small charge, enhancing long-haul comfort.

Read more about Finnairby Gabriel Leigh
Virgin Atlantic

Economy Delight offers priority check-in and boarding, plus extra legroom for comfort.


Upper Class provides fully flat beds and access to exclusive lounges at Heathrow.

British Airways

Upgrade to premium economy for 18 cm extra legroom, wider seats, and priority boarding.


Check plane type for legroom: 79 cm on most, but 74 cm on A321neo planes.

Airports
SEA

Use the SEA Spot Saver for free expedited security screening. Book online or via the flySEA app for Checkpoints 2, 3, and 5.

Read more about SEAby Harriet Baskas
LHR

Take the Heathrow Express for a quick 15-minute ride to London Paddington. Book tickets in advance for the best rates.

Read more about LHRby Kirstie Pickering
Our travel experts
Blane Bachelor

Blane Bachelor

Expert on KLM and Air France

Blane Bachelor

Blane Bachelor

Blane Bachelor is a journalist and editor specialising in travel and aviation who writes regularly for top global outlets. Born and raised in Florida, Blane has worked and lived in four countries, including the Netherlands, where she’s currently based with her family. Her favourite way to get to know a new destination is by running or riding a bike around town – or hearing a spooky ghost story about local history.

Read more
Gabriel Leigh

Gabriel Leigh

Expert on Finnair

Gabriel Leigh

Gabriel Leigh

Gabriel is a writer and video creator. As senior content producer for Flightradar24 and Monocle’s transport correspondent, he keeps a close eye on aviation in particular. He has also written travel articles for the likes of The New York Times. Born in New York but raised around the world, he now lives in Sweden. He’s been to 75 countries, flying 2.3 million miles on 113 airlines and through 234 airports in the process.

Read more
Laura Ratliff

Laura Ratliff

Expert on Virgin Atlantic

Laura Ratliff

Laura Ratliff

Laura Ratliff is a New York-based writer and editor. She lives in downtown Brooklyn with her husband and their beloved dogs. Originally from Texas, she now considers New York City her home. She typically spends more than 200,000 miles on a plane each year and stays in plenty of hotels.

Read more
Duncan Madden

Duncan Madden

Expert on British Airways

Duncan Madden

Duncan Madden

Duncan is a freelance travel writer, copywriter and book author in constant search of travel stories and the perpetual sensation of being on holiday. He’s never happier than when on a dusty trail in search of empty waves or ducking under the piste tape in search of snowbound solitude. British born, living in Germany, but happiest heading for the horizon. His first book, Found in Translation, explores the etymologies and stories of country names around the world and is out now.

Read more
Kirstie Pickering

Kirstie Pickering

Expert on LHR

Kirstie Pickering

Kirstie Pickering

Aviation and business journalist Kirstie didn’t leave England until she was 18 years old, but has since travelled to over 20 countries including Japan, Canada, and Iceland. Her travel expertise lies in European city breaks, including how to find the best locally-owned hotels and restaurants and how to optimise the airport experience for your needs.

Read more
Harriet Baskas

Harriet Baskas

Expert on SEA

Harriet Baskas

Harriet Baskas

Harriet is an award-winning journalist who is happiest in an airport or an unusual museum. Her stories about airports, air travel, and the business of travel have appeared on NBC News, CNBC, The Points Guy, and other outlets. She is the creator of the StuckatTheAirport.com blog and the author of nine books. When not out on the road or exploring the latest airport amenities, she’s home in Seattle getting ready for the next adventure.

Read more

Good to know - Cheap tickets from Seattle to London Heathrow Airport

Low seasonJanuary
Cheapest flight£254
Best time to beat the crowds (7% less expensive on average)
Most popular time to fly and prices are also 8% lower on average.
Flight from Seattle to London Heathrow Airport

When to book flights from Seattle to Heathrow

Are your dates flexible? Find out the best times to travel from Seattle to Heathrow based on our flight data from the last year. Discover the cheapest month and even day to fly.
Estimated return price
KAYAK looks at all historical flight data for each date to provide a predicted price for one-way trips or returns 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.

Flights from Seattle to Heathrow: the best tips from KAYAK users' own experiences

Insights shared by verified travellers who flew the route from Seattle to Heathrow 
Verified travelerFlew with British AirwaysSEA-LHRApr 2025
Make sure you have plenty of time between flights if you are delayed.
Verified travelerFlew with British AirwaysSEA-LHRApr 2024
Bring a sack lunch -- airport food was very expensive.

FAQs for booking Seattle to London Heathrow Airport flights

  • What is the cheapest flight from Seattle to London Heathrow Airport?

    In the last 3 days, the lowest price for a flight from Seattle to London Heathrow Airport was £254 for a one-way ticket and £389 for a return.

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

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

  • Which airlines offer Wi-Fi service onboard planes from Seattle to London Heathrow Airport?

    Air France, Delta, Virgin Atlantic, KLM, and American Airlines offer inflight Wi-Fi service on the Seattle to London Heathrow Airport flight route.

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

    The Boeing 787-10 Dreamliner is the aircraft model that flies most regularly on the Seattle to London Heathrow Airport flight route.

  • Which airline alliances offer flights from Seattle to London Heathrow Airport?

    oneworld, and SkyTeam are the airline alliances operating flights between Seattle and London Heathrow Airport, with oneworld being the most commonly used for this route.

  • On which days can I fly direct from Seattle to London Heathrow Airport?

    There are direct flights from Seattle to London Heathrow Airport on a daily basis.

  • Which is the best airline for flights from Seattle to London, Virgin Atlantic or Aer Lingus?

    The two airlines most popular with KAYAK users for flights from Seattle to London are Virgin Atlantic and Aer Lingus. With an average price for the route of £619 and an overall rating of 7.5, Virgin Atlantic is the most popular choice. Aer Lingus is also a great choice for the route, with an average price of £515 and an overall rating of 7.2.

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

    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 Heathrow Airport.

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

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

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

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional return ticket. You could then fly to London Heathrow Airport with an airline and back to Seattle with another airline.

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

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

KAYAK’s top tips for finding a cheap flight from Seattle to London Heathrow Airport

  • Looking for a cheap flight from London Heathrow Airport to Seattle? 25% of our users found flights on this route for £461 or less one-way and £489 or less round-trip.

Prefer to fly direct from Seattle to London Heathrow Airport?

 
Direct data is based off flight results for the next 60 days. Find direct flights from all airlines flying direct from Seattle/Tacoma Intl to London Heathrow.
Find which airlines fly direct from Seattle/Tacoma Intl Airport to London Heathrow Airport, which days they fly and book direct flights.

Direct departures

Seattle/Tacoma Intl to London Heathrow

Monday

British Airways, Delta, Virgin Atlantic

British Airways, Delta, +1 more

Tuesday

British Airways, Delta, Virgin Atlantic

British Airways, Delta, +1 more

Wednesday

British Airways, Delta

British Airways, Delta

Thursday

British Airways, Delta, Virgin Atlantic

British Airways, Delta, +1 more

Friday

British Airways, Delta

British Airways, Delta

Saturday

British Airways, Delta, Virgin Atlantic

British Airways, Delta, +1 more

Sunday

British Airways, Delta

British Airways, Delta

See more direct flights

Direct returns

London Heathrow to Seattle/Tacoma Intl

Monday

British Airways, Delta, Virgin Atlantic

British Airways, Delta, +1 more

Tuesday

British Airways, Delta, Virgin Atlantic

British Airways, Delta, +1 more

Wednesday

British Airways, Delta

British Airways, Delta

Thursday

British Airways, Delta, Virgin Atlantic

British Airways, Delta, +1 more

Friday

British Airways, Delta

British Airways, Delta

Saturday

British Airways, Delta, Virgin Atlantic

British Airways, Delta, +1 more

Sunday

British Airways, Delta

British Airways, Delta

See more direct flights

Reviews of the top 3 airlines flying from Seattle to Heathrow

 
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 Heathrow? 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.
7.5
Virgin AtlanticOverall score based on 670 reviews
8.1Crew
7.7Boarding
7.5Entertainment
7.3Comfort
6.9Food
Airline reviews

Great staff great experience, made a 2 hour delay very bearable

10.0 ExcellentAnonymous, Oct 2025LAX - LHR
Read more Virgin Atlantic reviews

Great staff great experience, made a 2 hour delay very bearable

Great staff, great experience, made a 2 hour delay very bearable

Food was the worst I’ve had on a VA flight. Normally it’s a lot better

I was my pleasure to fly virgin on my birthday for my first solo trip ever 🫶🏼

These are one of the older seat arrangements facing away from the windows! Not particularly convenient sets. No storage spaces. NO COAT HANGING HOOKS. Inconvenient business class seat compared to any other airlines of similar class. Staff are excellent! Extremely professional, friendly. Food is good too.

Overall, flight was excellent but check in was very slow for Premium Economy. Economy queue was shorter but we weren't allowed to use it.

The staff was not very polite but the flight was very very nice and comfortable and the entertainment was great

Great crew - old style upper class seats on the older fleet now feels dated

Premium economy more comfortable than economy, but not by much. Did was awful, do not try the omelette. Flight crew were helpful. Flight was delayed by over an hour. Overall but bad, arrived safely and thank God.

Food was excellent. Service was very good. Staff was very helpful to all passengers.

Our first flight from Venice to Dublin was delayed due to very bad weather and when we did arrive we were ushered out of the secure area to collect our luggage then told we could not Demeter as the US Customs team closed at 4pm. Thus we were stuck in Dublin for one night with hundreds of passengers scrambling for information and little help from the local staff. Many passengers were left without accommodation and told to find something on their own. We were also told we would get contacted with rebooking details and did not, requiring us to make those arrangements ourselves, in some cases at a very high out of pocket cost. Many passengers swore they would never fly on Aer Lingus again.

Fast and sensible boarding was absolutely amazing. But extortionate wifi and seats that barely moved, making me unable to sleep, didn't do a lot of favors.

Excellent flight and crew. Boarding at Dublin Airport was a very difficult trying to find the right gate.

I liked the front row seats. A lot of leg room. The check-in window needs to be longer

Conveyer belt at the check in area stopped working and check in process was significantly slowed down.

My flights with Aer Lingus were very good and I will definitely fly with them. Again in future trips to Ireland and Scotland.

Too hot. Asked for an extra glass of water and was ignored. Asked to sit in empty seats that were open because it was so hot and crowded and was denied and the seats were empty the entire flight

Terrible leg room - I’m 5’3” and my knees were touching the seat in front of me. When the person sitting in front of me leaned back, there was about 15 inches of space between my head and the TV screen which made it awkward to view movies. Last year they had decent food, but this year the only tasty item on the trip was dessert.

The flight was delayed leaving Philadelphia due to “catering” and consequently arrived in Dublin some 75 minutes later than scheduled. Consequently this caused me to miss my connecting flight to Glasgow and I had to spend the night in Dublin.

The flight from Cincinnati to Philadelphia was satisfactory and uneventful.

Flying on the Boeing 787 from Seattle to London was everything that I expected. Every thing was great.

Seat pitch is not enough to eat comfortably. When seat in front is reclined, your screen comes closer to your face. Ryanair seats are actually more comfortable.

The leg from Portland to Heathrow was great for a business class ticket. The BA leg from Heathrow to Lisbon was terrible. Basically coach seating with an empty seat between you and next passenger. Absolutely no leg room. Should not have been charged for business class and it was a 3 hour flight.

The flat beds. Other than that, the place was not clean.

Moved me away from my family and refused to fix it.

I have always been pleased with their service. Would not change a thing

Seating and food was the worst we have experienced in 35 years of traveling for both personal and busines .

Economy seats felt more cramped than other flights we have taken.7 hr, painful sitting hours 6 and 7. Web site difficult to deal with. Originally put in for 1 special meal due to type 2. Meal was awful. Tried to change selection to standard for return flight, on app and website, unable to complete that action.

I was sleeping during dinner service, no one bothered to offer meal later, I remained hungry….until I got a morning sandwich!

Need to offer Better food from LAX to London Service from London to Delhi very delayed after take off.

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

Information on your arrival and departure airports

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