What is the cheapest airline that flies from Seattle/Tacoma Intl to London?

WestJet is the most popular carrier operating from Seattle/Tacoma Intl to London

Which airport is the most popular layover for flights between Seattle and London?

Reykjavik (KEF) was the most common stop: 76% of momondo users choosing 1-stop flights on this route connected there.

How many flights depart from Seattle to London on average per week?

141 flights are operational weekly from Seattle to London as of September 2025. The most popular departure day for this route is Mon, with 15% of flights per week taking off on this day.

Which layover airport has the shortest travel time from Seattle to London?

Flights connecting via Reykjavik (KEF) have the shortest average one-way travel time: 12h 09m.

What airlines fly to London?

British Airways, Delta and Virgin Atlantic are the top three most popular airlines that fly to London from Seattle according to our data. British Airways is the first choice among our users, with 37% of people opting to fly with this airline when traveling to London. Keep in mind that there are 15 different airlines that fly to London on a routine basis, so you have a few additional options to choose from.

How many flights depart from Seattle to London on average per day?

As of September 2025, 20 flights take off from Seattle and land in London each day. The most common flight departure time for this route is 8:00PM, with 52% of daily flights taking off in the evening.

Which layover airport offers the lowest fares from Seattle to London?

Flights via Boston (BOS) offer the lowest average round-trip price of $652.

Which layover airport has the shortest connection time from Seattle to London?

Dublin (DUB) has the shortest average layover time for this route: 1h 54m.

Which airlines fly direct from Seattle to London?

Conveniently, you have a few options when it comes to flying nonstop from Seattle International Airport (SEA) to Heathrow Airport (LHR) in London. British Airways has two direct flights daily, while Virgin Atlantic, American Airlines, and Delta Airlines all offer one direct flight daily. The flight time is generally around 9h 30min. There are also multiple airlines that offer one-stop flights between SEA and LHR. These include United/Lufthansa, Air Canada, Finnair, Aer Lingus, Alaska/Icelandair, and more. These flights can take anywhere from 12 hours to 16 hours or more, depending on your layover time (which varies). Stopover cities include Amsterdam, Paris, and others. Currently, there are no direct flights between SEA and London Gatwick (LGW). There are also one-stop flights from London City Airport (LCY) and London Luton Airport (LTN), and two-stop flights from London Stansted Airport (STN). What is the best way to get in and out of airports in Seattle and London? Upon landing in Seattle and London, you have multiple options for navigating from the airport to your destination. It’s easy to get from Seattle-Tacoma International Airport (SEA) to downtown Seattle. You can use the Link Light Rail, which has trains departing every ten minutes or so. To get to the station from baggage claim, head up to the fourth floor and cross the skybridge to get to the parking garage level; there’s ample signage to guide you. This is the most cost-effective option. You can also opt to hail a cab, take a rideshare, or rent a car. Heathrow Airport (LHR) offers robust public transportation to get you from the airport to Central London. The fastest option is the Heathrow Express, which runs non-stop trains every 15 minutes (it takes just 15 minutes to make the journey). It’s also possible to rent a car or hail a cab (the latter is the most expensive option). That said, most locals take public transit because of how ubiquitous and convenient it is. In addition, you can take the Gatwick Express train to get from LGW to Central London; LCY is accessible via the Tube, bus, rental car, or taxi; or, travel from STN by bus, train, taxi, or rental car. What are the benefits of the different airports in Seattle and London? Seattle-Tacoma International Airport (SEA) is a destination in and of itself. You’ll find a great mix of local bookstores (like the popular Elliott Bay Book Company), cafes, restaurants, bars, and shops here. In addition, specialty services include massage options, shoeshine, manicures and pedicures, and more. While there are six airports in the London area, the two major ones are Heathrow (LHR) and Gatwick (LGW). There are some key differences between the two. Namely, LHR serves nearly every airline under the sun, so you have plenty of options when it comes to choosing a flight. As you might imagine, this airport also has a staggering number of shops, restaurants, and pubs. Premium lounges and spa services are available throughout. The biggest benefit to flying into LGW is that this airport can sometimes have cheaper flights (budget airlines like easyJet operate from here), and it’s generally not that crowded, so you don't have to worry about waiting in line for a long time at security. In terms of other airports in London, LTN has two top-notch lounges; LCY is the closest airport to Central London; and, STN serves over 160 destinations. What cities can you get to from Heathrow Airport in London? For travelers who want to explore other international cities, LHR makes for an excellent base. There are daily flights from this major hub to tons of exciting global hot spots, including Dubai, Tokyo, Amsterdam, Havana, Mexico City, Zurich, Milan, Nairobi, Perth, São Paulo, Tel Aviv, and more. Traveling to the U.S.? You can opt to fly Delta, American, or United to most major cities, such as San Diego, Austin, Denver, New Orleans, Nashville, Boston, Charlotte, Detroit, Newark, Los Angeles, Phoenix, Dallas, Kauai, New York, and Tampa (just to name a few). Access Amsterdam, Bucharest, Budapest and other European cities from LTN; fly to Barcelona, Dublin, Prague, and others from LCY; go to Milan, Seville, Lisbon, and other cities from STN.

When did momondo last update prices for flights from Seattle/Tacoma Intl Airport to London?

Prices for flights from Seattle/Tacoma Intl Airport to London are refreshed on a daily basis.

How many operators does momondo search for flights from Seattle/Tacoma Intl Airport to London?

The number of operators available for flights from Seattle/Tacoma Intl Airport to London is 15 as of September 2025.

How old do you have to be to fly from Seattle/Tacoma Intl Airport to London?

The minimum age a child must be to fly alone is five but airlines that offer an unaccompanied minor (UNMR) service will have their own age restrictions, including rules around flight length, timings, and stopovers. We always recommend checking with the individual airline you are booking with to travel from Seattle/Tacoma Intl Airport to London.

What documentation or ID do you need to fly to London?

The travel and health documents you'll need for your trip to London 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. It is always advisable to seek advice from your airline or a trusted third party, such as IATA.

$265 Cheap Flights from Seattle to London in 2025/26

Q: What is the typical price of a round-trip flight between Seattle and London?

Prices are currently low for flights on this route. Typical prices usually range from $603 to $805. The lowest price recently found on this route was $508.

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Find the cheapest flights from Seattle to London

Round-trip

One-way

Last minute

Direct

Cheap round-trip flights

7:00 pm - 2:40 pmSEA-LGW

11h 40m1 stop

3:40 pm - 8:40 pmLGW-SEA

13h 00m1 stop

$508Icelandair

Find Deal

Wed, Oct 1 - Wed, Oct 15

5:35 pm - 11:20 amSEA-LHR

9h 45mnonstop

3:25 pm - 11:15 amLHR-SEA

27h 50m1 stop

$508Virgin Atlantic

Find Deal

Sun, Sep 28 - Tue, Oct 14

4:48 pm - 10:30 amSEA-LHR

9h 42mnonstop

6:20 am - 1:20 pmLHR-SEA

15h 00m1 stop

$509Delta

Find Deal

Wed, Nov 12 - Wed, Nov 19

4:48 pm - 10:30 amSEA-LHR

9h 42mnonstop

6:20 am - 11:25 amLHR-SEA

13h 05m1 stop

$510Air France

Find Deal

Wed, Nov 12 - Thu, Nov 20

5:35 pm - 11:20 amSEA-LHR

9h 45mnonstop

6:30 am - 11:50 amLHR-SEA

13h 20m1 stop

$511Delta

Find Deal

Tue, Oct 14 - Thu, Oct 23

2:35 pm - 10:55 amSEA-LGW

12h 20m1 stop

11:55 am - 5:00 pmLGW-SEA

13h 05m1 stop

$511Icelandair

Find Deal

Thu, Nov 6 - Tue, Nov 18

1:30 pm - 6:50 amSEA-LHR

9h 20mnonstop

9:25 am - 11:10 amLHR-SEA

9h 45mnonstop

$512British Airways

Find Deal

Wed, Oct 1 - Tue, Oct 14

1:30 pm - 6:50 amSEA-LHR

9h 20mnonstop

9:50 am - 11:35 amLHR-SEA

9h 45mnonstop

$513British Airways

Find Deal

Mon, Oct 6 - Wed, Oct 22

8:25 pm - 2:15 pmSEA-LHR

9h 50mnonstop

6:15 am - 11:15 amLHR-SEA

13h 00m1 stop

$514Air France

Find Deal

Wed, Oct 15 - Wed, Oct 22

3:05 pm - 4:35 pmSEA-LCY

17h 30m1 stop

5:50 pm - 12:35 pmLCY-SEA

25h 45m1 stop

$576KLM

Find Deal

Wed, Mar 4 - Tue, Mar 10

Delta flights from Seattle to London

Our best Delta deals on Seattle to London flight tickets

Delta

Nov 12

SEA4:48 pmSeattle/Tacoma Intl

9h 42m

LHR10:30 amLondon Heathrow

Nov 19

LHR6:20 amLondon Heathrow

15h 00m

1 stop

SEA1:20 pmSeattle/Tacoma Intl

$509

Find similar

Delta

Oct 1

SEA8:25 pmSeattle/Tacoma Intl

9h 50m

LHR2:15 pmLondon Heathrow

Oct 10

LHR6:15 amLondon Heathrow

13h 00m

1 stop

SEA11:15 amSeattle/Tacoma Intl

$510

Find similar

Delta

Oct 1

SEA5:35 pmSeattle/Tacoma Intl

9h 45m

LHR11:20 amLondon Heathrow

Oct 14

LHR6:30 amLondon Heathrow

17h 35m

1 stop

SEA4:05 pmSeattle/Tacoma Intl

$511

Find similar

British Airways flights from Seattle to London

Our best British Airways deals on Seattle to London flight tickets

British Airways

Oct 1

SEA1:30 pmSeattle/Tacoma Intl

9h 20m

LHR6:50 amLondon Heathrow

Oct 14

LHR9:25 amLondon Heathrow

9h 45m

SEA11:10 amSeattle/Tacoma Intl

$512

Find similar

British Airways

Oct 6

SEA1:30 pmSeattle/Tacoma Intl

9h 20m

LHR6:50 amLondon Heathrow

Oct 22

LHR9:50 amLondon Heathrow

9h 45m

SEA11:35 amSeattle/Tacoma Intl

$513

Find similar

British Airways

Jan 6

SEA6:50 pmSeattle/Tacoma Intl

9h 30m

LHR12:20 pmLondon Heathrow

Jan 14

LHR2:55 pmLondon Heathrow

10h 00m

SEA4:55 pmSeattle/Tacoma Intl

$518

Find similar

Fly from

Fly to

Route

Depart

Return

Price

SeattleLondon

SEA - LGW

SEALGW

Seattle/Tacoma Intl

Wed 10/1

7:00 pm-2:40 pm

1 stop11h 40m

London Gatwick

Wed 10/15

3:40 pm-8:40 pm

1 stop13h 00m

$508

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Sun 9/28

5:35 pm-11:20 am

Nonstop9h 45m

London Heathrow

Tue 10/14

3:25 pm-11:15 am

1 stop27h 50m

$508

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Wed 11/12

4:48 pm-10:30 am

Nonstop9h 42m

London Heathrow

Wed 11/19

6:20 am-1:20 pm

1 stop15h 00m

$509

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Wed 11/12

4:48 pm-10:30 am

Nonstop9h 42m

London Heathrow

Thu 11/20

6:20 am-11:25 am

1 stop13h 05m

$510

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Tue 10/14

5:35 pm-11:20 am

Nonstop9h 45m

London Heathrow

Thu 10/23

6:30 am-11:50 am

1 stop13h 20m

$511

SeattleLondon

SEA - LGW

SEALGW

Seattle/Tacoma Intl

Thu 11/6

2:35 pm-10:55 am

1 stop12h 20m

London Gatwick

Tue 11/18

11:55 am-5:00 pm

1 stop13h 05m

$511

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Wed 10/1

1:30 pm-6:50 am

Nonstop9h 20m

London Heathrow

Tue 10/14

9:25 am-11:10 am

Nonstop9h 45m

$512

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Mon 10/6

1:30 pm-6:50 am

Nonstop9h 20m

London Heathrow

Wed 10/22

9:50 am-11:35 am

Nonstop9h 45m

$513

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Wed 10/15

8:25 pm-2:15 pm

Nonstop9h 50m

London Heathrow

Wed 10/22

6:15 am-11:15 am

1 stop13h 00m

$514

SeattleLondon

SEA - LCY

SEALCY

Seattle/Tacoma Intl

Wed 3/4

3:05 pm-4:35 pm

1 stop17h 30m

London City

Tue 3/10

5:50 pm-12:35 pm

1 stop25h 45m

$576

Flights are sorted by cheapest round-trip flights first.

Showing 1-10 of 20 resultsSorted by cheapest first

How to get the cheapest flight ticket from Seattle to London

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

Layovers

Other information

What is the typical price of a round-trip flight between Seattle and London?

What is the cheapest month to fly to London?

The cheapest month to fly to London from Seattle is in October. Flight prices, which tend to average around $661, are often lower during this time because this is during the off-season. The month of August is another great option to travel to London, with average flight prices from Seattle averaging around $676.

What is the cheapest day to depart on your flight to London?

The cheapest day to depart from Seattle to London is on a Tuesday. Travelers who choose to depart for London on a Tuesday will often find tickets for as low as $813. If your travel schedule is flexible, try to avoid departing on a Saturday because tickets tend to average around $916. These prices are subject to change though, so be sure to set up a Price Alert for flights to London.

What is the cheapest time of day to depart on your flight to London?

Flying to London from Seattle in the evening is the least expensive time of day to depart. momondo users have found prices as low as $843 when looking at flights departing in the evening. Flights to London are more costly in the morning, with an average ticket price of $980. Departure times in the morning fall within the peak daily travel times, which is why tickets can be more expensive.

What is the cheapest Seattle/Tacoma Intl to London flight route?

Fly from Seattle/Tacoma Intl to London Heathrow for the best Seattle/Tacoma Intl - London flight prices

How far in advance should I book a flight to London?

You are more likely to see cheaper flights to London from Seattle when booking weeks ahead of your departure date. In general, you can expect to find flights to London for around $804 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to London from Seattle for as low as $707 on momondo.

What cabin class options are available on Seattle/Tacoma Intl to London flights?

There are 4 cabin classes available to choose from on Seattle/Tacoma Intl to London flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.

How have Seattle to London flight prices changed over time?

As of September 2025, prices for Seattle to London flights are approximately 43% cheaper when compared to flights at the same time last year.

When to book flights from Seattle to London

Are you open to changing your travel dates? Check out the ideal times to fly from Seattle to London according to our flight data. Find out which month and days have the cheapest flights.

Estimated round-trip price

Cheap Seattle to London (SEA to LON) flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from Seattle to London

Best Price Found	$417
Fastest flight time	9h 20m
Direct flights	Every day
Airports in London	1 airport

The best one-way flight to London from Seattle in the past 72 hours is $417. The best round-trip flight deal from Seattle to London found on momondo in the last 72 hours is $654.

The fastest flight from Seattle to London takes 9h 20m

Direct flights go from Seattle to London every day.

There is 1 airport near London: London Heathrow (LHR)

Search flight deals

How far is Seattle/Tacoma Intl to London by plane?
London is 4781.3 mi away from Seattle/Tacoma Intl. By plane, this route typically takes 9h 20m.
When did momondo last update prices for flights from Seattle/Tacoma Intl Airport to London?
Prices for flights from Seattle/Tacoma Intl Airport to London are refreshed on a daily basis.
How many operators does momondo search for flights from Seattle/Tacoma Intl Airport to London?
The number of operators available for flights from Seattle/Tacoma Intl Airport to London is 15 as of September 2025.
How old do you have to be to fly from Seattle/Tacoma Intl Airport to London?
The minimum age a child must be to fly alone is five but airlines that offer an unaccompanied minor (UNMR) service will have their own age restrictions, including rules around flight length, timings, and stopovers. We always recommend checking with the individual airline you are booking with to travel from Seattle/Tacoma Intl Airport to London.
What documentation or ID do you need to fly to London?
The travel and health documents you'll need for your trip to London 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. It is always advisable to seek advice from your airline or a trusted third party, such as IATA.
What is the most popular plane model from Seattle to London?
Based on momondo bookings for this flight route, the most popular plane model on flight routes from Seattle to London is Boeing 787-10 Dreamliner (30.89% of total bookings). The next most popular plane models are Airbus A330-900neo (21.16%), Boeing 787-9 Dreamliner (11.12%), and Airbus A330-200 (10.98%).
What is the most popular airline from Seattle to London?
Based on momondo bookings for flights between Seattle and London, the leading airline is British Airways, making up 22% of the total bookings. Other popular airlines include Delta with 20%, Icelandair with 17%, and Virgin Atlantic with 13%.

Best airlines flying from Seattle to London

Compare and see reviews for airlines that fly from Seattle to London with momondo

Airline	Rating	Free Cancellation	Price
Lufthansa	PriceFrom $378	Free Cancellation	Rating 6.8 7,409 reviews	Search Lufthansa flights
Icelandair	PriceFrom $484	Free Cancellation	Rating 7.0 545 reviews	Search Icelandair flights
Aer Lingus	PriceFrom $523	Free Cancellation	Rating 7.2 1,277 reviews	Search Aer Lingus flights
Scandinavian Airlines	PriceFrom $532	Free Cancellation	Rating 7.4 1,486 reviews	Search Scandinavian Airlines flights
Air France	PriceFrom $532	Free Cancellation	Rating 7.4 1,468 reviews	Search Air France flights
United Airlines	PriceFrom $547	Free Cancellation	Rating 7.4 8,926 reviews	Search United Airlines flights
Finnair	PriceFrom $556	Free Cancellation	Rating 7.6 1,324 reviews	Search Finnair flights
British Airways	PriceFrom $556	Free Cancellation	Rating 6.7 7,367 reviews	Search British Airways flights
Delta	PriceFrom $563	Free Cancellation	Rating 7.9 7,961 reviews	Search Delta flights
American Airlines	PriceFrom $569	Free Cancellation	Rating 7.2 10,000 reviews	Search American Airlines flights

Alaska Airlines Flights From Seattle to London
Alaska Airlines flight deals from Seattle to London start from $853 round-trip. Over the 13 Alaska Airlines flights for this route in a normal week, average airfare is usually $1,021 round-trip - but some users have found much cheaper deals with momondo.
Delta Flights From Seattle to London
Across 7,961 Delta reviews on momondo, the average score is 7.9/10. Delta flies from Seattle to London about 14 times each week, with ticket deals ranging from $563 to $846. Price data is based on momondo searches in the last 72 hours.

Gatwick

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Dover

Luton

Slough

Milton Keynes

Hayes

Guildford

Dartford

Crawley

Stansted

Chelmsford

Brentwood

Ilford

Folkestone

Colchester

Watford

Wembley

Richmond

Croydon

Why use momondo?

Why should I use momondo to find a flight deal from Seattle to London?

momondo collates all your flight options in one place and lets you filter them to find the perfect flight from Seattle to London. momondo saves you time and could save you money on your trip.

Can I find flights from Seattle to London with flexible booking policies on momondo?

Yes. All flights to London from Seattle on momondo can be compared and filtered by various policies on offer, including flexible booking.

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?

If you are simply researching potential flights to London, momondo offers a useful price alert feature which will track prices for flights to London from Seattle and alert you when they change.

An easier way to manage your London trip

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London Gatwick Airport

London Heathrow Airport

London Luton Airport

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Popular cities in the United Kingdom

Flights to Manchesterfrom $391

Flights to Edinburghfrom $396

Flights to Glasgowfrom $374

Flights to Birminghamfrom $389

Flights to Newcastle upon Tynefrom $430

Flights to Belfastfrom $514

Flights to Bristolfrom $425

Flights to Invernessfrom $407

Flights to Liverpoolfrom $441

Flights to Aberdeenfrom $487

Flights to Leedsfrom $453

Flights to Cardifffrom $444

Cheap flights from Seattle to London from $265

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 10/4. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.

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Delta flights from Seattle to London

Our best Delta deals on Seattle to London flight tickets

British Airways flights from Seattle to London

Our best British Airways deals on Seattle to London flight tickets

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How to get the cheapest flight ticket from Seattle to London

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

What is the typical price of a round-trip flight between Seattle and London?

What is the cheapest month to fly to London?

What is the cheapest day to depart on your flight to London?

What is the cheapest time of day to depart on your flight to London?

What is the cheapest Seattle/Tacoma Intl to London flight route?

Fly from Seattle/Tacoma Intl to London Heathrow for the best Seattle/Tacoma Intl - London flight prices

How far in advance should I book a flight to London?

What cabin class options are available on Seattle/Tacoma Intl to London flights?

There are 4 cabin classes available to choose from on Seattle/Tacoma Intl to London flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.

How have Seattle to London flight prices changed over time?

As of September 2025, prices for Seattle to London flights are approximately 43% cheaper when compared to flights at the same time last year.

What is the cheapest airline that flies from Seattle/Tacoma Intl to London?

WestJet is the most popular carrier operating from Seattle/Tacoma Intl to London

What airlines fly to London?

Which airport is the most popular layover for flights between Seattle and London?

Reykjavik (KEF) was the most common stop: 76% of momondo users choosing 1-stop flights on this route connected there.

Which layover airport offers the lowest fares from Seattle to London?

Flights via Boston (BOS) offer the lowest average round-trip price of $652.

Which layover airport has the shortest travel time from Seattle to London?

Flights connecting via Reykjavik (KEF) have the shortest average one-way travel time: 12h 09m.

Which layover airport has the shortest connection time from Seattle to London?

Dublin (DUB) has the shortest average layover time for this route: 1h 54m.

How many flights depart from Seattle to London on average per day?

As of September 2025, 20 flights take off from Seattle and land in London each day. The most common flight departure time for this route is 8:00PM, with 52% of daily flights taking off in the evening.

How many flights depart from Seattle to London on average per week?

141 flights are operational weekly from Seattle to London as of September 2025. The most popular departure day for this route is Mon, with 15% of flights per week taking off on this day.

When to book flights from Seattle to London

Cheap Seattle to London (SEA to LON) flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from Seattle to London

Best Price Found

Fastest flight time

Direct flights

Airports in London

How far is Seattle/Tacoma Intl to London by plane?

When did momondo last update prices for flights from Seattle/Tacoma Intl Airport to London?

How many operators does momondo search for flights from Seattle/Tacoma Intl Airport to London?

How old do you have to be to fly from Seattle/Tacoma Intl Airport to London?

What documentation or ID do you need to fly to London?

What is the most popular plane model from Seattle to London?

What is the most popular airline from Seattle to London?

Best airlines flying from Seattle to London

Compare and see reviews for airlines that fly from Seattle to London with momondo

Alaska Airlines Flights From Seattle to London

Delta Flights From Seattle to London

Traveling to a place near London?

Why use momondo?

Why should I use momondo to find a flight deal from Seattle to London?

Can I find flights from Seattle to London with flexible booking policies on momondo?

How can momondo help me find flights 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?

An easier way to manage your London 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.

Get notified when prices go down

Daily price changes in your inbox - only with Price Alerts.

Find better results for your trip to the United Kingdom

Fly into one of these airports located in London