How long is the flight from Seattle to London?

A quick flight from Seattle to London can take about 9h 45m. Icelandair provides one of the quickest options available for as low as $607. The distance between Seattle and London is about 4783 mi. When browsing for deals, the options you’ll see will be for both nonstop flights and flights with stops.

What are the cheapest airlines flying from Seattle to London round-trip?

Cheapflights users have booked flights from Seattle to London round-trip from $378. Other airlines that can offer you cheap pricing are Icelandair, from $483, and Aer Lingus, from $500. Users have found that Lufthansa is 50% cheaper than the other options available to this destination.

What are the cheapest airlines to fly from Seattle to London one-way?

One-way options have recently been found by users for as low as $387 on WestJet. Other airlines that offer cheap prices include United Airlines from $394 and Icelandair from $396 one-way.

In terms of precipitation, rainfall in London ranges from 1.6 - 2.8 inches per month. January is typically the wettest month, when rainfall can reach 2.8 in. July is typically the driest time to visit London when rainfall is around 1.6 in.

If weather is an important factor for your trip to London, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 62.6 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 39.2 F).

What are the most popular routes from Seattle to London?

When deciding which route to take from Seattle to London consider Seattle/Tacoma Intl - London Heathrow, Seattle/Tacoma Intl - London Gatwick or Seattle/Tacoma Intl - London City as they are the most popular.

What are the cheapest flights from Seattle to London?

Looking at all options, your cheapest flight can be booked for $326. While the most popular route (Seattle/Tacoma Intl - London Heathrow) can be booked for $510 on average, our data indicates $2,213 when flying from Seattle to London.

What are the most reliable airlines from Seattle to London?

Consider Aeromexico (90%), KLM (83%) or Air France (83%) when booking your flight. These represent the most reliable airlines when flying from Seattle to London.

What are the most popular airlines that fly from Seattle to London?

Before booking your flight from Seattle to London check out the most popular airlines for this route: American Airlines, Air France or Alaska Airlines.

Most accurate provider : When it comes to deals on Seattle-London flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Seattle-London flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Seattle-London flight searches over the past month and is updated monthly.

Most trusted provider : When it comes to deals on Seattle-London flights, Cheapflights users trust FlightHub the most. FlightHub has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for Seattle-London flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

What airport do you fly from for flights from Seattle to London?

If you book a flight to London from Seattle, you will be flying from Seattle/Tacoma Intl, which is the city’s only airport. Seattle/Tacoma Intl (SEA) is located 11.4 mi from the center of Seattle. There are 20 flights from Seattle/Tacoma Intl to London per day from 14 different airlines.

Can I find deals for flights from Seattle to London that include hotel bookings?

Yes. In addition to deals on Seattle to London flights, Cheapflights offers vacation packages that include both flights and hotel.

How can I find direct flights from Seattle to London?

After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Seattle to London.

Can I find deals for business class flights from Seattle to London?

Yes. Cheapflights offers flight deals from Seattle to London by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

$386+ Flights from Seattle to London

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Cheapflights Tip: The best prices from Seattle/Tacoma Intl to London are usually found in October or January, booked 64 days in advance, depart on a Tuesday or Wednesday and return on a Wednesday

Cheap flight deals from Seattle to London

Most accurate provider	FlightHub 3 stars
Most trusted provider	FlightHub 3 stars
Round-trip from	$512 (CrystalTravel)
One-way from	$386 (Kiwi.com)
Popular in	June
Cheapest in	October
Average price	$660
Good round-trip deal	$664 or less
Good one-way deal	$409 or less

Provider with most accurate pricing for Seattle/Tacoma Intl-London (LON) flight deals.

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Provider most trusted by Cheapflights users for Seattle/Tacoma Intl-London (LON) flights.

Search Deals

From Seattle/Tacoma Intl to London (LON)

Search Deals

One-way flight from Seattle/Tacoma Intl to London (LON)

Search Deals

Highest demand for flights based on searches. 15% potential increase in price ($137 potential increase over avg. RT price).

Search Deals

Cheapest flight prices on average. 2% potential price decrease ($23 potential savings vs. average RT price).

Search Deals

Average for round-trip flights in October 2025

Search Deals

Price to beat on a round-trip flight from Seattle/Tacoma Intl to London (LON).

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Price to beat on a one-way flight from Seattle/Tacoma Intl to London (LON).

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Find flight deals from Seattle to London

Cheapest flights from Seattle to London
Explore the most affordable flight options available from Seattle to London. Find the lowest fares from popular airlines and budget airlines, with prices last updated on October 1, 2025.

Tue 11/112:35 pmSEA - LHR

1 stop20h 55mIcelandair

Mon 12/812:15 pmLHR - SEA

1 stop12h 45mIcelandair

Deal found 9/30

$515

Sun 11/22:35 pmSEA - LGW

1 stop12h 20mIcelandair

Sat 11/811:55 amLGW - SEA

1 stop13h 05mIcelandair

Deal found 9/29

$517

Sun 11/22:35 pmSEA - LGW

1 stop12h 20mIcelandair

Tue 11/1811:55 amLGW - SEA

1 stop13h 05mIcelandair

Deal found 9/30

$520

Wed 11/122:35 pmSEA - STN

2 stops24h 15mMultiple Airlines

Wed 11/196:30 amSTN - SEA

2 stops18h 30mMultiple Airlines

Deal found 9/29

$522

Tue 11/112:35 pmSEA - LHR

1 stop20h 55mIcelandair

Tue 11/188:35 pmLHR - SEA

1 stop28h 25mIcelandair

Deal found 9/30

$523

Tue 10/283:35 pmSEA - LTN

2 stops21h 30mMultiple Airlines

Tue 11/49:00 amLTN - SEA

2 stops16h 00mMultiple Airlines

Deal found 9/29

$523

Wed 11/122:35 pmSEA - LGW

1 stop12h 20mIcelandair

Wed 11/1911:55 amLGW - SEA

1 stop13h 05mIcelandair

Deal found 9/29

$525

Wed 11/262:35 pmSEA - LGW

1 stop12h 20mIcelandair

Fri 12/511:55 amLGW - SEA

1 stop13h 05mIcelandair

Deal found 9/29

$526

Wed 12/32:35 pmSEA - STN

2 stops19h 15mMultiple Airlines

Sun 12/148:30 amSTN - SEA

2 stops16h 30mMultiple Airlines

Deal found 9/30

$527

Thu 11/132:35 pmSEA - LHR

1 stop20h 55mIcelandair

Thu 11/208:35 pmLHR - SEA

1 stop28h 25mIcelandair

Deal found 9/29

$527

Wed 11/122:35 pmSEA - LTN

2 stops24h 30mMultiple Airlines

Wed 11/196:50 amLTN - SEA

2 stops18h 10mMultiple Airlines

Deal found 9/29

$527

Wed 11/268:05 pmSEA - STN

1 stop18h 45mMultiple Airlines

Sun 12/710:15 amSTN - SEA

1 stop16h 05mMultiple Airlines

Deal found 9/28

$528

Best flights from Seattle to London
Discover carefully curated flight deals from Seattle to London that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated October 1, 2025.

Wed 11/268:05 pmSEA - STN

1 stop18h 45mMultiple Airlines

Sun 12/710:15 amSTN - SEA

1 stop16h 05mMultiple Airlines

Deal found 9/28

$528

Tue 11/42:35 pmSEA - LGW

1 stop12h 20mIcelandair

Wed 11/1911:55 amLGW - SEA

1 stop13h 05mIcelandair

Deal found 9/30

$552

Tue 10/285:45 pmSEA - LHR

Nonstop9h 45mDelta

Tue 11/46:30 amLHR - SEA

1 stop13h 15mDelta

Deal found 9/29

$607

Sun 3/85:40 pmSEA - LHR

Nonstop9h 50mVirgin Atlantic

Wed 3/186:20 amLHR - SEA

1 stop14h 40mVirgin Atlantic

Deal found 9/29

$621

Mon 3/91:55 pmSEA - LHR

3 stops34h 15mUnited Airlines

Thu 3/196:30 amLHR - SEA

1 stop13h 40mUnited Airlines

Deal found 9/30

$622

Thu 11/1312:40 pmSEA - LHR

2 stops21h 50mScandinavian Airlines

Mon 11/177:30 pmLHR - SEA

2 stops34h 55mScandinavian Airlines

Deal found 9/30

$629

Tue 11/1110:53 amSEA - LCY

2 stops17h 57mSWISS

Tue 11/259:15 amLCY - SEA

2 stops22h 29mSWISS

Deal found 9/30

$655

Wed 12/38:05 pmSEA - STN

1 stop13h 45mMultiple Airlines

Sun 12/1410:15 amSTN - SEA

1 stop16h 05mMultiple Airlines

Deal found 9/29

$528

Fri 11/72:35 pmSEA - LGW

1 stop12h 20mIcelandair

Sat 11/2211:55 amLGW - SEA

1 stop13h 05mIcelandair

Deal found 9/30

$552

Wed 12/38:05 pmSEA - LTN

1 stop19h 00mMultiple Airlines

Sun 12/148:05 amLTN - SEA

1 stop18h 15mMultiple Airlines

Deal found 9/29

$528

Sun 11/94:48 pmSEA - LHR

Nonstop9h 42mDelta

Mon 11/1711:45 amLHR - SEA

1 stop32h 00mDelta

Deal found 9/30

$607

Sun 12/72:35 pmSEA - LGW

1 stop12h 20mIcelandair

Thu 12/1111:55 amLGW - SEA

1 stop13h 05mIcelandair

Deal found 9/29

$552

Sun 3/85:50 amSEA - LHR

1 stop23h 00mUnited Airlines

Wed 3/181:25 pmLHR - SEA

2 stops40h 04mUnited Airlines

Deal found 9/30

$623

Sat 10/252:10 pmSEA - LHR

2 stops20h 30mScandinavian Airlines

Sat 11/16:40 amLHR - SEA

2 stops22h 47mScandinavian Airlines

Deal found 9/30

$629

Wed 11/127:20 amSEA - LCY

2 stops15h 55mVirgin Atlantic

Mon 11/245:05 pmLCY - SEA

1 stop26h 40mVirgin Atlantic

Deal found 9/30

$646

Mon 3/92:47 pmSEA - LCY

2 stops19h 18mSWISS

Mon 3/167:10 pmLCY - SEA

2 stops33h 19mSWISS

Deal found 10/1

$655

Tue 11/115:50 amSEA - STN

3 stops28h 30mMultiple Airlines

Tue 11/189:45 pmSTN - SEA

3 stops32h 21mMultiple Airlines

Deal found 9/29

$546

Mon 11/107:20 pmSEA - LHR

Nonstop9h 30mDelta

Tue 11/186:30 amLHR - SEA

1 stop13h 15mDelta

Deal found 9/30

$607

Sat 3/1411:50 pmSEA - LHR

2 stops24h 20mUnited Airlines

Tue 3/241:25 pmLHR - SEA

2 stops36h 34mUnited Airlines

Deal found 9/29

$627

Thu 11/1312:40 pmSEA - LHR

2 stops21h 00mScandinavian Airlines

Tue 11/187:30 pmLHR - SEA

2 stops34h 55mScandinavian Airlines

Deal found 9/30

$629

Sun 3/13:05 pmSEA - LCY

1 stop18h 15mVirgin Atlantic

Wed 3/115:05 pmLCY - SEA

1 stop26h 30mVirgin Atlantic

Deal found 9/30

$650

Tue 11/112:00 pmSEA - LTN

2 stops22h 05mMultiple Airlines

Wed 11/195:10 pmLTN - SEA

2 stops27h 00mMultiple Airlines

Deal found 9/29

$559

Sun 3/14:45 pmSEA - LHR

Nonstop9h 45mDelta

Thu 3/196:30 amLHR - SEA

1 stop13h 05mDelta

Deal found 10/1

$615

Mon 3/97:20 amSEA - LCY

2 stops16h 55mVirgin Atlantic

Mon 3/168:05 pmLCY - SEA

1 stop23h 30mVirgin Atlantic

Deal found 10/1

$655

Fri 12/51:05 pmSEA - LGW

2 stops20h 45mSWISS

Sat 12/136:40 pmLGW - SEA

2 stops34h 20mSWISS

Deal found 9/29

$748

Wed 11/263:10 pmSEA - STN

2 stops21h 55mMultiple Airlines

Wed 12/38:30 amSTN - SEA

2 stops35h 40mMultiple Airlines

Deal found 10/1

$573

Tue 12/22:35 pmSEA - LGW

1 stop12h 20mIcelandair

Sun 12/1411:55 amLGW - SEA

1 stop13h 05mIcelandair

Deal found 9/29

$703

Tue 11/116:00 amSEA - LCY

2 stops17h 15mVirgin Atlantic

Tue 11/189:20 amLCY - SEA

2 stops21h 05mVirgin Atlantic

Deal found 9/29

$656

Tue 12/232:35 pmSEA - LGW

1 stop12h 20mIcelandair

Sun 1/1111:55 amLGW - SEA

1 stop13h 05mIcelandair

Deal found 9/29

$711

Sun 11/25:40 pmSEA - STN

2 stops18h 00mMultiple Airlines

Sat 11/85:55 amSTN - SEA

2 stops17h 45mMultiple Airlines

Deal found 9/30

$596

Last-minute flights from Seattle to London
Discover last-minute flight deals from Seattle to London. Data last updated October 1, 2025 and is based on user searches.

Sun 10/57:00 pmSEA - LGW

1 stop11h 40mIcelandair

Wed 10/223:40 pmLGW - SEA

1 stop13h 00mIcelandair

Deal found 9/29

$525

Sun 10/53:45 pmSEA - LHR

1 stop12h 10mIcelandair

Wed 10/229:25 pmLHR - SEA

1 stop28h 25mIcelandair

Deal found 9/29

$530

Mon 10/67:00 pmSEA - LHR

1 stop32h 55mIcelandair

Wed 10/229:25 pmLHR - SEA

1 stop28h 25mIcelandair

Deal found 9/29

$532

Mon 10/133:45 pmSEA - LHR

1 stop12h 10mIcelandair

Wed 10/229:25 pmLHR - SEA

1 stop31h 15mIcelandair

Deal found 9/29

$565

Wed 10/1512:45 pmSEA - LHR

2 stops24h 55mScandinavian Airlines

Wed 10/229:05 pmLHR - SEA

2 stops48h 55mScandinavian Airlines

Deal found 9/30

$554

Thu 10/163:45 pmSEA - LGW

1 stop14h 55mIcelandair

Mon 11/311:55 amLGW - SEA

1 stop13h 05mIcelandair

Deal found 9/29

$526

Thu 10/167:00 pmSEA - LHR

1 stop32h 55mIcelandair

Mon 11/38:35 pmLHR - SEA

1 stop28h 25mIcelandair

Deal found 9/29

$533

Thu 10/1612:45 pmSEA - LHR

2 stops20h 55mScandinavian Airlines

Tue 10/217:05 amLHR - SEA

2 stops38h 55mScandinavian Airlines

Deal found 10/1

$552

Sun 10/263:35 pmSEA - LHR

1 stop12h 15mIcelandair

Sun 11/28:35 pmLHR - SEA

1 stop28h 25mIcelandair

Deal found 9/29

$531

Mon 10/273:35 pmSEA - LGW

1 stop12h 20mIcelandair

Fri 11/711:55 amLGW - SEA

1 stop13h 05mIcelandair

Deal found 9/29

$558

Tue 10/283:35 pmSEA - LTN

2 stops21h 30mMultiple Airlines

Tue 11/49:00 amLTN - SEA

2 stops16h 00mMultiple Airlines

Deal found 9/29

$523

Tue 10/283:35 pmSEA - LGW

1 stop12h 20mIcelandair

Wed 11/511:55 amLGW - SEA

1 stop13h 05mIcelandair

Deal found 10/1

$560

One-way flights from Seattle to London
Search for one-way flight options from Seattle to London. Find affordable one-way fares based on user searches. Data last updated October 1, 2025.

Fri 12/59:00 amSEA - STN

2 stops20h 20mMultiple Airlines

Deal found 10/1

$386

Mon 12/298:05 pmSEA - LHR

1 stop12h 45mAer Lingus

Deal found 9/29

$386

Fri 11/283:10 pmSEA - SEN

3 stops23h 50mMultiple Airlines

Deal found 9/30

$387

Fri 10/241:50 pmSEA - LGW

2 stops21h 30mMultiple Airlines

Deal found 9/30

$387

Wed 10/2210:55 pmSEA - LHR

2 stops29h 10mWestJet

Deal found 10/1

$387

Mon 10/610:10 amSEA - LTN

2 stops39h 05mMultiple Airlines

Deal found 9/30

$387

Sun 12/283:40 pmSEA - LHR

2 stops31h 30mLufthansa

Deal found 9/29

$388

Fri 10/241:50 pmSEA - LTN

2 stops23h 10mMultiple Airlines

Deal found 9/30

$388

Thu 11/611:07 amSEA - LGW

2 stops25h 33mMultiple Airlines

Deal found 9/29

$389

Tue 12/93:40 pmSEA - LHR

1 stop12h 10mAir Canada

Deal found 10/1

$389

Wed 10/1511:10 pmSEA - LGW

3 stops34h 00mMultiple Airlines

Deal found 9/29

$390

Fri 10/2412:17 amSEA - LHR

2 stops28h 08mMultiple Airlines

Deal found 9/30

$390

Fly from

Fly to

Route

Depart

Return

Price

SeattleLondon

SEA - STN

SEASTN

Seattle/Tacoma Intl

Wed 11/26

8:05 pm-10:50 pm

1 stop18h 45m

London Stansted

Sun 12/7

10:15 am-6:20 pm

1 stop16h 05m

$528

SeattleLondon

SEA - STN

SEASTN

Seattle/Tacoma Intl

Wed 12/3

8:05 pm-5:50 pm

1 stop13h 45m

London Stansted

Sun 12/14

10:15 am-6:20 pm

1 stop16h 05m

$528

SeattleLondon

SEA - LTN

SEALTN

Seattle/Tacoma Intl

Wed 12/3

8:05 pm-11:05 pm

1 stop19h 00m

London Luton

Sun 12/14

8:05 am-6:20 pm

1 stop18h 15m

$528

SeattleLondon

SEA - STN

SEASTN

Seattle/Tacoma Intl

Tue 11/11

5:50 am-6:20 pm

3 stops28h 30m

London Stansted

Tue 11/18

9:45 pm-10:06 pm

3 stops32h 21m

$546

SeattleLondon

SEA - LGW

SEALGW

Seattle/Tacoma Intl

Tue 11/4

2:35 pm-10:55 am

1 stop12h 20m

London Gatwick

Wed 11/19

11:55 am-5:00 pm

1 stop13h 05m

$552

SeattleLondon

SEA - LGW

SEALGW

Seattle/Tacoma Intl

Fri 11/7

2:35 pm-10:55 am

1 stop12h 20m

London Gatwick

Sat 11/22

11:55 am-5:00 pm

1 stop13h 05m

$552

SeattleLondon

SEA - LGW

SEALGW

Seattle/Tacoma Intl

Sun 12/7

2:35 pm-10:55 am

1 stop12h 20m

London Gatwick

Thu 12/11

11:55 am-5:00 pm

1 stop13h 05m

$552

SeattleLondon

SEA - LTN

SEALTN

Seattle/Tacoma Intl

Tue 11/11

2:00 pm-8:05 pm

2 stops22h 05m

London Luton

Wed 11/19

5:10 pm-12:10 pm

2 stops27h 00m

$559

SeattleLondon

SEA - STN

SEASTN

Seattle/Tacoma Intl

Wed 11/26

3:10 pm-9:05 pm

2 stops21h 55m

London Stansted

Wed 12/3

8:30 am-12:10 pm

2 stops35h 40m

$573

SeattleLondon

SEA - STN

SEASTN

Seattle/Tacoma Intl

Sun 11/2

5:40 pm-7:40 pm

2 stops18h 00m

London Stansted

Sat 11/8

5:55 am-3:40 pm

2 stops17h 45m

$596

Flights are sorted by cheapest round-trip flights first.

Deals found on 9/30

Showing 1-10 of 60 results

...

Compare providers for flights from Seattle to London

Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Seattle to London in October.

Provider	Price Accuracy	Trust Score*
Expedia	Price Accuracy2 stars	Trust Score*3 stars
FlightHub	Price Accuracy3 stars	Trust Score*3 stars
eDreams	Price Accuracy3 stars	Trust Score*3 stars
AranGrant	Price Accuracy3 stars	Trust Score*3 stars
oojo	Price Accuracy3 stars	Trust Score*3 stars
Ovago	Price Accuracy2 stars	Trust Score*2 stars
Cheapflightsfares	Price Accuracy2 stars	Trust Score*1 star
Mytrip	Price Accuracy2 stars	Trust Score*3 stars
Trip.com	Price Accuracy2 stars	Trust Score*3 stars
Gotogate	Price Accuracy2 stars	Trust Score*2 stars

*The Trust Score is based on feedback from users after their booking experience. It measures overall satisfaction, helping us identify issues like hidden fees, problems during the ticketing process, and the quality of customer service. This score is our best indicator of the provider's quality and reliability.

Most accurate provider: When it comes to deals on Seattle-London flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Seattle-London flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Seattle-London flight searches over the past month and is updated monthly.
Most trusted provider: When it comes to deals on Seattle-London flights, Cheapflights users trust FlightHub the most. FlightHub has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for Seattle-London flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

The best insider tips for Seattle to London flights

Cheapflights partnered with top experts to bring you the best recommendations for your Seattle to London trip

Airports

SEA

Plan to arrive at SEA at least two hours before your flight due to potentially long security lines.

LHR

Take the Heathrow Express for the fastest route into central London from LHR, arriving at Paddington Station.

Our travel experts

Ramsey Qubein

Expert on LHR

Brandon Schultz

Expert on SEA

Best time to book a flight from Seattle to London

Have a flexible travel schedule? Discover the best time to fly to London from Seattle with our price prediction graph.

Estimated round-trip price

Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Cheapflights Insights

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

How far ahead should I book a flight from Seattle to London?

Booking 64 days in advance of your planned departure date is, on average, the best time to get cheap flights from Seattle to London. The general trend is that the closer you book to the departure date, the more expensive your flight will be.

What is the cheapest month to book a flight from Seattle to London?

Currently, November is the cheapest month in which you can book a flight from Seattle to London (average of $661). Flying from Seattle to London in June is currently the most expensive (average of $1,096). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

What is the cheapest time of day to fly from SEA to LON?

One of the essential ways to save on airfare from Seattle to London is to remain as flexible as possible. Flights that are in the morning tend to be the most expensive. A flight in the evening could potentially save you up to 15% on airfare.

What is the cheapest day to fly from Seattle to London?

Travelers seeking maximum savings on their Seattle to London flight should consider departing on Tuesday evenings when fares are most often at their lowest. Friday mornings flights should be avoided if possible as fares are typically the most expensive at this time.

Weekly flight availability from Seattle to London

The most flights from SEA to LON are scheduled on a Monday (21 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (15 on average).

What’s the top layover airport for flights from Seattle to London?

Reykjavik (KEF) – chosen by Cheapflights users on 83% of 1-stop itineraries from Seattle to London on Cheapflights.

What’s the cheapest layover airport for flights from Seattle to London?

Reykjavik (KEF) is the most affordable 1-stop option, with an average round-trip price of $530.

What’s the fastest layover option from Seattle to London?

Flights via Dublin (DUB) have the shortest average one-way travel time for 1-stop routes: 11h 35m.

Which airport typically offers the quickest layover for flights from Seattle to London?

Flights via Reykjavik (KEF) offer the fastest connection on this route, with an average layover time of 1h 29m.

Reviews of airlines servicing London

Peruse reviews from past customers who have flown with Delta, Virgin Atlantic, and Icelandair from Seattle to London to help guide your decision. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.

Delta

8.0

Very good

7,961 reviews

Reviews

1 / 20

10.0

Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!

Delta

8.0

Very good

7,961 reviews

Delta

8.0

Very good

7,961 reviews

Reviews

1 / 20

10.0

Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!

Virgin Atlantic

7.4

Good

665 reviews

Delta

8.0

Very good

7,961 reviews

Reviews

1 / 20

10.0

Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!

Icelandair

7.0

Good

546 reviews

Delta

8.0

Very good

7,961 reviews

Reviews

1 / 20

10.0

Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!

Iberia

7.0

Good

2,966 reviews

Delta

8.0

Very good

7,961 reviews

Reviews

1 / 20

10.0

Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!

British Airways

6.7

Okay

7,413 reviews

Delta

8.0

Very good

7,961 reviews

Reviews

1 / 20

10.0

Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!

Related info for your journey

What airport do you fly from for flights from Seattle to London?
If you book a flight to London from Seattle, you will be flying from Seattle/Tacoma Intl, which is the city’s only airport. Seattle/Tacoma Intl (SEA) is located 11.4 mi from the center of Seattle. There are 20 flights from Seattle/Tacoma Intl to London per day from 14 different airlines.
How long is the flight from Seattle to London?
A quick flight from Seattle to London can take about 9h 45m. Icelandair provides one of the quickest options available for as low as $607. The distance between Seattle and London is about 4783 mi. When browsing for deals, the options you’ll see will be for both nonstop flights and flights with stops.
What are the cheapest airlines flying from Seattle to London round-trip?
Cheapflights users have booked flights from Seattle to London round-trip from $378. Other airlines that can offer you cheap pricing are Icelandair, from $483, and Aer Lingus, from $500. Users have found that Lufthansa is 50% cheaper than the other options available to this destination.
What are the cheapest airlines to fly from Seattle to London one-way?
One-way options have recently been found by users for as low as $387 on WestJet. Other airlines that offer cheap prices include United Airlines from $394 and Icelandair from $396 one-way.
What are the most popular routes from Seattle to London?
When deciding which route to take from Seattle to London consider Seattle/Tacoma Intl - London Heathrow, Seattle/Tacoma Intl - London Gatwick or Seattle/Tacoma Intl - London City as they are the most popular.
What are the most reliable airlines from Seattle to London?
Consider Aeromexico (90%), KLM (83%) or Air France (83%) when booking your flight. These represent the most reliable airlines when flying from Seattle to London.
What are the cheapest flights from Seattle to London?
Looking at all options, your cheapest flight can be booked for $326. While the most popular route (Seattle/Tacoma Intl - London Heathrow) can be booked for $510 on average, our data indicates $2,213 when flying from Seattle to London.
Can I find deals for flights from Seattle to London that include hotel bookings?
Yes. In addition to deals on Seattle to London flights, Cheapflights offers vacation packages that include both flights and hotel.
How can I find direct flights from Seattle to London?
After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Seattle to London.
Can I find deals for business class flights from Seattle to London?
Yes. Cheapflights offers flight deals from Seattle to London by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.
What is the cheapest month to book a flight from Seattle to London?
Currently, November is the cheapest month in which you can book a flight from Seattle to London (average of $661). Flying from Seattle to London in June is currently the most expensive (average of $1,096). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

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Top 10 airlines flying from Seattle to London

Airline	Cheapest	Average	Flexibility	On-time
Lufthansa	Cheapest$378	Average$865	FlexibilityNo cancel fee	On-time76%
Icelandair	Cheapest$483	Average$651	FlexibilityNo cancel fee	On-time76%
Aer Lingus	Cheapest$500	Average$729	FlexibilityNo cancel fee	On-timeN/A
Air France	Cheapest$517	Average$785	FlexibilityNo cancel fee	On-time77%
American Airlines	Cheapest$520	Average$860	FlexibilityNo cancel fee	On-time71%
Scandinavian Airlines	Cheapest$532	Average$871	FlexibilityNo cancel fee	On-time77%
United Airlines	Cheapest$547	Average$824	FlexibilityNo cancel fee	On-time69%
British Airways	Cheapest$547	Average$801	FlexibilityNo cancel fee	On-time70%
Finnair	Cheapest$556	Average$716	FlexibilityNo cancel fee	On-time76%
Delta	Cheapest$562	Average$844	FlexibilityNo cancel fee	On-timeN/A

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$386+ Cheap flights from Seattle (SEA) to London (LON)

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 12/5. Fares are subject to change and may not be available on all flights or dates of travel.

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Cheapflights Tip: The best prices from Seattle/Tacoma Intl to London are usually found in October or January, booked 64 days in advance, depart on a Tuesday or Wednesday and return on a Wednesday

Cheap flight deals from Seattle to London

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Find flight deals from Seattle to London

Cheapest flights from Seattle to LondonExplore the most affordable flight options available from Seattle to London. Find the lowest fares from popular airlines and budget airlines, with prices last updated on October 1, 2025.

Explore the most affordable flight options available from Seattle to London. Find the lowest fares from popular airlines and budget airlines, with prices last updated on October 1, 2025.

Cheapflights Fare Finder

Use the filters below to find and compare flights from Seattle to London that are best for you.

Compare providers for flights from Seattle to London

Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.

Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Seattle to London in October.

The best insider tips for Seattle to London flights

Cheapflights partnered with top experts to bring you the best recommendations for your Seattle to London trip

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Best time to book a flight from Seattle to London

Have a flexible travel schedule? Discover the best time to fly to London from Seattle with our price prediction graph.

Cheapflights Insights

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

How far ahead should I book a flight from Seattle to London?

Use this chart to determine the optimal time to book a round-trip flight from Seattle to London. Price data was last updated on September 26, 2025.

What is the cheapest month to book a flight from Seattle to London?

What is the cheapest time of day to fly from SEA to LON?

Find hourly flight availability from Seattle to London. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated October 1, 2025.

What is the cheapest day to fly from Seattle to London?

Use this chart to determine the cheapest time to fly round-trip from Seattle to London. Price data was last updated on December 16, 2024.

Weekly flight availability from Seattle to London

Explore weekly flight availability from Seattle to London. Discover flights operating on different days of the week, giving you the flexibility to choose a travel day that best fits your plans. Compare info to find the most convenient option for your journey. Data last updated October 1, 2025.

What’s the top layover airport for flights from Seattle to London?

Share of 1-stop round-trip flights from Seattle to London chosen by Cheapflights users in the past 12 months, using the same layover each way.

What’s the cheapest layover airport for flights from Seattle to London?

Average round-trip fare for 1-stop flights from Seattle to London, chosen by Cheapflights users in the past 12 months, with the same layover each way.

What’s the fastest layover option from Seattle to London?

Shortest average travel time for 1-stop one-way flights from Seattle to London, based on itineraries clicked by Cheapflights users over the past 12 months, grouped by layover airport.

Which airport typically offers the quickest layover for flights from Seattle to London?

Average layover duration for 1-stop one-way flights from Seattle to London, chosen by Cheapflights users in the last 12 months, grouped by stopover airport.

Reviews of airlines servicing London

Peruse reviews from past customers who have flown with Delta, Virgin Atlantic, and Icelandair from Seattle to London to help guide your decision. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.

Related info for your journey

Find useful and relevant information for your journey from Seattle to London. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

What airport do you fly from for flights from Seattle to London?

How long is the flight from Seattle to London?

What are the cheapest airlines flying from Seattle to London round-trip?

What are the cheapest airlines to fly from Seattle to London one-way?

What are the most popular routes from Seattle to London?

What are the most reliable airlines from Seattle to London?

What are the cheapest flights from Seattle to London?

Can I find deals for flights from Seattle to London that include hotel bookings?

How can I find direct flights from Seattle to London?

Can I find deals for business class flights from Seattle to London?

What is the cheapest month to book a flight from Seattle to London?

Traveling to a place near London?

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Alternative routes for Seattle to London

See prices for flight routes from nearby airports that may be better suited for you.

Cheapest flights from Seattle to London
Explore the most affordable flight options available from Seattle to London. Find the lowest fares from popular airlines and budget airlines, with prices last updated on October 1, 2025.