How long is the flight from Seattle to London?

Airlines like United Airlines, Scandinavian Airlines, and Delta fly from Seattle to London in about 15h 40m. The time it takes to get you to your destination can typically vary by up to 17h 05m. The distance from Seattle to London is about 4807 mi. Both multi-stop and direct flights can be found to your destination and back.

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

Cheapflights users have booked flights from Seattle to London round-trip from £499. Other airlines that can offer you cheap pricing are British Airways, from £527, and Virgin Atlantic, from £560. Alaska Airlines is currently priced 24% below the average price you’ll pay for this route.

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

The cheapest airline one-way is Icelandair, with whom users have recently found tickets for as low as £129. However, be on the lookout for offers from Virgin Atlantic and British Airways, as they are both options that can get you from Seattle to London for a low price.

In terms of precipitation, rainfall in London ranges from 40.0 - 70.0 inches per month. January is typically the wettest month, when rainfall can reach 70.0 mm. July is typically the driest time to visit London when rainfall is around 40.0 mm.

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 17.0 C. Travellers hoping to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 4.0 C).

What are the most popular routes from Seattle to London?

The most popular route from Seattle to London is Seattle/Tacoma Intl - London Heathrow. You may also consider Seattle/Tacoma Intl - London Gatwick or Seattle/Tacoma Intl - London Stansted.

What are the cheapest flights from Seattle to London?

The cheapest flight price from Seattle to London is £240. On average you can expect to pay £565. The most popular route, (Seattle/Tacoma Intl - London Heathrow), can usually be booked for £356.

What are the most reliable airlines from Seattle to London?

No one likes to see their flight delayed. When booking a flight from Seattle to London consider choosing KLM (93%), SAUDIA (93%) or Air France (93%) as they are the most reliable in getting you off to your destination on time.

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

The most popular airlines flying from Seattle to London are Virgin Atlantic, Alaska Airlines and British Airways. Something to consider prior to booking your flight.

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

Seattle/Tacoma Intl (SEA) is the airport you will fly out of if you book a flight from Seattle to London. You should not have trouble finding flights to London from Seattle/Tacoma Intl; the airport handles an average of 24 outbound flights to London per day. You should also have plenty of airline options to choose from since 3 airlines have flights from the Seattle airport to London. It is only a 11.4 mi journey to Seattle/Tacoma Intl (SEA) from Seattle’s city center.

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 holiday 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.

£254+ Cheap Flights from Seattle to London

Cheapflights Tip: The best prices from Seattle/Tacoma Intl to London are usually found in January or April, booked 82 days in advance, depart on a Wednesday or Monday and return on a Thursday

Cheap flight deals from Seattle to London

Enter your travel dates to find the best prices.

Cheapest

Best

Direct

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One-way

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 8 October 2026.

Mon 16/1114:35 -

2 stops18h 20m

Sun 22/1116:00 -

3 stops33h 00m

Deal found 6/10£570

Mon 26/1007:45 -

2 stops28h 40m

Tue 3/1120:15 -

1 stop23h 45m

Deal found 6/10£571

Tue 20/1018:05 -

1 stop16h 45m

Tue 27/1010:25 -

1 stop13h 30m

Deal found 7/10£572

Sun 8/1114:50 -

2 stops22h 30m

Sat 14/1117:30 -

2 stops27h 30m

Deal found 8/10£572

Mon 2/1113:50 -

2 stops19h 05m

Sun 15/1109:15 -

2 stops34h 45m

Deal found 4/10£573

Fri 6/1114:50 -

3 stops34h 20m

Wed 11/1118:05 -

3 stops32h 17m

Deal found 4/10£573

Sun 6/1215:00 -

1 stop20h 25m

Mon 14/1210:25 -

1 stop13h 30m

Deal found 6/10£574

Mon 7/1214:35 -

1 stop12h 15m

Tue 15/1212:15 -

1 stop12h 45m

Deal found 6/10£574

Tue 3/1117:50 -

1 stop13h 10m

Thu 5/1110:25 -

1 stop13h 30m

Deal found 8/10£575

Sat 5/1214:35 -

1 stop12h 15m

Wed 13/112:15 -

1 stop12h 45m

Deal found 7/10£575

Mon 12/1015:40 -

2 stops20h 30m

Mon 19/1021:00 -

3 stops31h 40m

Deal found 7/10£576

Thu 10/1214:35 -

1 stop20h 55m

Tue 26/112:15 -

1 stop12h 45m

Deal found 8/10£576

Best flights from Seattle to London
Discover carefully curated flight deals from Seattle to London that have cost, travel time, and stopovers in mind to ensure you get the best travel experience. Data last updated 8 October 2026.

Fri 6/1119:05 -

1 stop32h 45m

Mon 9/1111:05 -

2 stops44h 02m

Deal found 5/10£628

Sun 13/1207:38 -

2 stops17h 42m

Fri 8/106:40 -

2 stops23h 24m

Deal found 6/10£638

Wed 9/1216:50 -

Nonstop9h 50m

Mon 1/211:45 -

1 stop32h 02m

Deal found 5/10£681

Wed 4/1116:50 -

Nonstop9h 50m

Sun 15/1112:20 -

Nonstop10h 30m

Deal found 4/10£739

Fri 19/320:05 -

1 stop19h 30m

Sat 27/306:30 -

1 stop18h 40m

Deal found 6/10£745

Thu 10/1217:50 -

1 stop17h 35m

Thu 4/210:25 -

1 stop13h 30m

Deal found 5/10£764

Sun 8/1110:27 -

1 stop13h 48m

Mon 23/1110:05 -

1 stop18h 03m

Deal found 4/10£789

Thu 29/1017:05 -

1 stop15h 40m

Thu 5/1110:00 -

2 stops30h 41m

Deal found 4/10£835

Thu 3/1207:38 -

2 stops24h 22m

Thu 17/1217:00 -

2 stops37h 02m

Deal found 5/10£647

Tue 8/1216:05 -

1 stop15h 40m

Wed 3/210:00 -

1 stop13h 03m

Deal found 5/10£687

Fri 11/1207:20 -

2 stops24h 40m

Sat 6/206:40 -

2 stops22h 10m

Deal found 5/10£649

Tue 8/1216:05 -

1 stop15h 40m

Fri 18/1210:00 -

1 stop13h 13m

Deal found 5/10£687

Sun 8/1110:26 -

2 stops21h 34m

Mon 23/1110:20 -

2 stops19h 44m

Deal found 4/10£659

Sat 13/320:05 -

1 stop18h 30m

Sat 20/317:25 -

1 stop31h 45m

Deal found 7/10£798

Thu 11/323:10 -

2 stops26h 25m

Sat 20/316:10 -

1 stop28h 55m

Deal found 7/10£841

Sat 21/1123:07 -

1 stop23h 43m

Thu 3/1206:30 -

1 stop13h 20m

Deal found 6/10£722

Thu 12/1113:16 -

2 stops43h 14m

Mon 16/1106:30 -

1 stop18h 40m

Deal found 8/10£867

Sat 16/116:05 -

1 stop15h 40m

Sun 24/110:00 -

1 stop13h 13m

Deal found 5/10£733

Wed 28/1015:35 -

2 stops24h 00m

Sun 8/1117:25 -

1 stop31h 45m

Deal found 6/10£882

Fri 19/318:00 -

Nonstop9h 40m

Sat 27/306:20 -

1 stop15h 30m

Deal found 4/10£733

Thu 10/1222:50 -

2 stops32h 10m

Mon 1/210:25 -

1 stop13h 30m

Deal found 5/10£1,008

Thu 19/1106:00 -

1 stop17h 05m

Thu 3/1212:20 -

Nonstop10h 30m

Deal found 8/10£743

Mon 16/1119:05 -

1 stop37h 25m

Sun 22/1117:25 -

2 stops35h 22m

Deal found 6/10£917

Find flight deals from Seattle to London

Round-trip from	£568
One-way from	£254
Popular in	June
Cheapest in	January
Average price	£624
Good round-trip deal	£739 or less
Good one-way deal	£294 or less

United Airlines
12/1-13/1
4 total stops
39h 17m total
Seattle to London

Search Deals

Icelandair
16/10-31/12
1 total stop
11h 40m total
Seattle to London

Search Deals

Highest demand for flights based on searches. 17% potential increase in price (£104 potential increase over avg. return price).

Search Deals

Cheapest flight prices on average. 3% potential price decrease (£17 potential savings vs. average return price).

Search Deals

Average for round-trip flights in October 2026

Search Deals

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

Search Deals

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

Search Deals

Fly from

Fly to

Route

Depart

Return

Price

Cheapest return flight

SeattleLondon

SEA Seattle/Tacoma Intl - LHR London Heathrow

SEALHR

Seattle/Tacoma Intl

Fri 2/4

19:00-11:55

1 stop32h 55m

London Heathrow

Wed 31/12

00:00-15:00

Nonstop0h 00m

£257

Fastest return journey

SeattleLondon

SEA Seattle/Tacoma Intl - LHR London Heathrow

SEALHR

Seattle/Tacoma Intl

Sat 3/4

13:35-06:50

Nonstop9h 15m

London Heathrow

Wed 31/12

00:00-15:00

Nonstop0h 00m

£284

SeattleLondon

SEA Seattle/Tacoma Intl - LHR London Heathrow

SEALHR

Seattle/Tacoma Intl

Fri 2/4

21:50-15:35

Nonstop9h 45m

London Heathrow

Wed 31/12

00:00-15:00

Nonstop0h 00m

£284

SeattleLondon

SEA Seattle/Tacoma Intl - LHR London Heathrow

SEALHR

Seattle/Tacoma Intl

Sat 9/1

16:55-10:40

Nonstop9h 45m

London Heathrow

Wed 31/12

00:00-15:00

Nonstop0h 00m

£284

SeattleLondon

SEA Seattle/Tacoma Intl - LGW London Gatwick

SEALGW

Seattle/Tacoma Intl

Fri 5/2

15:30-15:45

1 stop16h 15m

London Gatwick

Wed 31/12

00:00-15:00

Nonstop0h 00m

£287

SeattleLondon

SEA Seattle/Tacoma Intl - LGW London Gatwick

SEALGW

Seattle/Tacoma Intl

Sat 27/2

16:05-15:45

1 stop15h 40m

London Gatwick

Wed 31/12

00:00-15:00

Nonstop0h 00m

£287

SeattleLondon

SEA Seattle/Tacoma Intl - LGW London Gatwick

SEALGW

Seattle/Tacoma Intl

Fri 26/2

15:30-15:45

1 stop16h 15m

London Gatwick

Wed 31/12

00:00-15:00

Nonstop0h 00m

£287

SeattleLondon

SEA Seattle/Tacoma Intl - LGW London Gatwick

SEALGW

Seattle/Tacoma Intl

Sat 6/2

16:05-15:45

1 stop15h 40m

London Gatwick

Wed 31/12

00:00-15:00

Nonstop0h 00m

£287

SeattleLondon

SEA Seattle/Tacoma Intl - LGW London Gatwick

SEALGW

Seattle/Tacoma Intl

Fri 29/1

06:05-09:00

2 stops18h 55m

London Gatwick

Wed 31/12

00:00-15:00

Nonstop0h 00m

£291

SeattleLondon

SEA Seattle/Tacoma Intl - LHR London Heathrow

SEALHR

Seattle/Tacoma Intl

Sat 7/11

08:30-07:10

3 stops38h 40m

London Heathrow

Wed 31/12

00:00-15:00

Nonstop0h 00m

£302

Flights are sorted by cheapest return flights first.

Deals found on 6/10

Showing 1-10 of 44 resultsSorted by cheapest first

...

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.

SEA-LON

SEA-LHR

SEA-LGW

Estimated return 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

SEA-LON

SEA-LHR

SEA-LGW

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

Currently, January is the cheapest month in which you can book a flight from Seattle to London (average of £515). Flying from Seattle to London in June is currently the most expensive (average of £919). 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?

When flying from Seattle to London, the time of day you decide to fly out makes little to no difference towards the overall price you’ll pay on tickets.

Weekly flight availability from Seattle to London

The most flights from SEA to LON are scheduled on a Tuesday (25 on average). You will have fewer flight options on Monday, which is when the least amount of flights are scheduled (24 on average).

How much does it cost for a return flight from Seattle to London?

Airfare is typical for this route at the moment.

Seattle to London flights typically cost between £542 and £772 in January.
The cheapest return price found within the last 5 days was £568 on United Airlines (12 Jan–13 Jan).

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

Reykjavik (KEF) – chosen by Cheapflights users on 50% of one-stop itineraries from Seattle to London on Cheapflights.

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

Reykjavik (KEF) is the most affordable one-stop option, with an average return flight price of £378.

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

Flights via Reykjavik (KEF) have the shortest average one-way travel time for one-stop routes: 12h 15m.

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

Flights via Reykjavik (KEF) offer the fastest connection on this route, with an average stopover time of 1h 25m.

How often are flights from Seattle to London delayed?

About 14% of weekly flights between Seattle and London have experienced delays in the past year, with the average delay time being 130 minutes.

What is the most punctual flight time for Seattle to London flights?

Historically, flights departing at night are less likely to be delayed, whereas flights leaving in the evening tend to experience delays more often.

What day of the week experiences the fewest flight delays on this route?

Saturday tends to have the lowest number of delays on this route, whereas Thursday has historically faced a higher average of delays compared to other days of the week.

Which airline has the best punctuality record on Seattle to London flights?

Over the past year, Virgin Atlantic have had the lowest number of delays on this route, with just 5% of flights being delayed.

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

The price you pay for your flight from Seattle to London may vary depending on when you book. For the best chance of a lower fare, look to book 64 days in advance of your trip. Fares are likely to increase a fortnight or so before your departure date.

Reviews of airlines servicing London

Get a feel of what it's like to fly with Alaska Airlines and Virgin Atlantic from Seattle to London by reading reviews from past customers. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.

Alaska Airlines

7.9

Good

13,037 reviews

Check prices

Reviews

1 / 20

6.0

Good

Anonymous,Jul 2026

SEA - LHR

Alaska has a brilliant crew. And the seats are good. As much as i loved my trip from Heathrow to Seattle, i definitely did not feel the same on the return flight. A lot was due to feeling very cramped and unfortunately for me, i had a kicker behind me and a passenger who did not stop moving (but constantly) next to me. The good was not good and i noticed that most people around me left most of their meal. The ice cream was very nice. I did not have breakfast. However the food was very nice on the way to Seattle

Alaska Airlines

7.9

Good

13,037 reviews

Alaska Airlines

7.9

Good

13,037 reviews

Check prices

Reviews

1 / 20

6.0

Good

Anonymous,Jul 2026

SEA - LHR

Virgin Atlantic

7.5

Good

694 reviews

Alaska Airlines

7.9

Good

13,037 reviews

Check prices

Reviews

1 / 20

6.0

Good

Anonymous,Jul 2026

SEA - LHR

Related info for your journey

What airport do you fly from for flights from Seattle to London?
Seattle/Tacoma Intl (SEA) is the airport you will fly out of if you book a flight from Seattle to London. You should not have trouble finding flights to London from Seattle/Tacoma Intl; the airport handles an average of 24 outbound flights to London per day. You should also have plenty of airline options to choose from since 3 airlines have flights from the Seattle airport to London. It is only a 11.4 mi journey to Seattle/Tacoma Intl (SEA) from Seattle’s city center.
How long is the flight from Seattle to London?
Airlines like United Airlines, Scandinavian Airlines, and Delta fly from Seattle to London in about 15h 40m. The time it takes to get you to your destination can typically vary by up to 17h 05m. The distance from Seattle to London is about 4807 mi. Both multi-stop and direct flights can be found to your destination and back.
What are the cheapest airlines flying from Seattle to London round-trip?
Cheapflights users have booked flights from Seattle to London round-trip from £499. Other airlines that can offer you cheap pricing are British Airways, from £527, and Virgin Atlantic, from £560. Alaska Airlines is currently priced 24% below the average price you’ll pay for this route.
What are the cheapest airlines to fly from Seattle to London one-way?
The cheapest airline one-way is Icelandair, with whom users have recently found tickets for as low as £129. However, be on the lookout for offers from Virgin Atlantic and British Airways, as they are both options that can get you from Seattle to London for a low price.
What are the most popular routes from Seattle to London?
The most popular route from Seattle to London is Seattle/Tacoma Intl - London Heathrow. You may also consider Seattle/Tacoma Intl - London Gatwick or Seattle/Tacoma Intl - London Stansted.
What are the most reliable airlines from Seattle to London?
No one likes to see their flight delayed. When booking a flight from Seattle to London consider choosing KLM (93%), SAUDIA (93%) or Air France (93%) as they are the most reliable in getting you off to your destination on time.
What are the cheapest flights from Seattle to London?
The cheapest flight price from Seattle to London is £240. On average you can expect to pay £565. The most popular route, (Seattle/Tacoma Intl - London Heathrow), can usually be booked for £356.
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 holiday 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, January is the cheapest month in which you can book a flight from Seattle to London (average of £515). Flying from Seattle to London in June is currently the most expensive (average of £919). 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 3 airlines flying from Seattle to London

Airline	Cheapest	Average	Flexibility	On-time
Alaska Airlines	Cheapest£499	Average£739	FlexibilityNo cancel fee	On-time75%	Search Alaska Airlines flights
British Airways	Cheapest£527	Average£692	FlexibilityNo cancel fee	On-time70%	Search British Airways flights
Virgin Atlantic	Cheapest£560	Average£665	FlexibilityNo cancel fee	On-time72%	Search Virgin Atlantic flights

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How does Cheapflights help users find flights from Seattle to London?

Deals for Seattle to London flights are sourced from 900+ travel sites when you use Cheapflights. When all flight results come back, Cheapflights lets you sort and filter flights using different criteria to choose better, like price, airport, cabin class, and plenty of other options.

Why should you use Cheapflights to find cheap flight tickets from Seattle to London?

Cheapflights simply makes it quick and affordable to book flights from Seattle to London by bringing together all flight options from hundreds of airlines and agencies online — and put it in one place for you to choose from. Plus, Cheapflights is 100% free to use for all.

Can Cheapflights find flights from Seattle to London with no change fees?

Users can book flights with no change fees policies with our dedicated filters. Book flights from Seattle to London flexibly with Cheapflights today.

Can Cheapflights notify me if prices for flights from Seattle to London become cheaper?

Yes, and it’s super simple to set up. Click the bell icon next to the flight deals above and provide a valid email address to enable Price Alerts. That’s it!

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Cheap flights from Seattle to London from £254

This is the cheapest retur flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 16/10. Fares are subject to change and may not be available on all flights or dates of travel.

Cheap 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 8 October 2026.

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 8 October 2026.

Best flights from Seattle to LondonDiscover carefully curated flight deals from Seattle to London that have cost, travel time, and stopovers in mind to ensure you get the best travel experience. Data last updated 8 October 2026.

Discover carefully curated flight deals from Seattle to London that have cost, travel time, and stopovers in mind to ensure you get the best travel experience. Data last updated 8 October 2026.

Direct flights from Seattle to LondonExplore direct flight options from Seattle to London based on user searches, and compare prices and availability for your desired travel dates. Data last updated 8 October 2026.

Explore direct flight options from Seattle to London based on user searches, and compare prices and availability for your desired travel dates. Data last updated 8 October 2026.

Last-minute flights from Seattle to LondonDiscover last-minute flight deals from Seattle to London. Data last updated 8 October 2026 and is based on user searches.

Discover last-minute flight deals from Seattle to London. Data last updated 8 October 2026 and is based on user searches.

One-way flights from Seattle to LondonSearch for one-way flight options from Seattle to London. Find affordable one-way fares based on user searches. Data last updated 8 October 2026.

Search for one-way flight options from Seattle to London. Find affordable one-way fares based on user searches. Data last updated 8 October 2026.

Find flight deals from Seattle to London

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Cheapflights Fare Finder

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

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

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 8 October 2026.

When flying from Seattle to London, the time of day you decide to fly out makes little to no difference towards the overall price you’ll pay on tickets.

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 8 October 2026.

The most flights from SEA to LON are scheduled on a Tuesday (25 on average). You will have fewer flight options on Monday, which is when the least amount of flights are scheduled (24 on average).

How much does it cost for a return flight from Seattle to London?

Airfare is typical for this route at the moment.

Seattle to London flights typically cost between £542 and £772 in January.The cheapest return price found within the last 5 days was £568 on United Airlines (12 Jan–13 Jan).

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

Share of one-stop return flights from Seattle to London chosen by Cheapflights users in the past 12 months, using the same stopover each way.

Reykjavik (KEF) – chosen by Cheapflights users on 50% of one-stop itineraries from Seattle to London on Cheapflights.

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

Average return fare for one-stop flights from Seattle to London, chosen by Cheapflights users in the past 12 months, with the same stopover each way.

Reykjavik (KEF) is the most affordable one-stop option, with an average return flight price of £378.

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

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

Flights via Reykjavik (KEF) have the shortest average one-way travel time for one-stop routes: 12h 15m.

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

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

Flights via Reykjavik (KEF) offer the fastest connection on this route, with an average stopover time of 1h 25m.

How often are flights from Seattle to London delayed?

About 14% of weekly flights between Seattle and London have experienced delays in the past year, with the average delay time being 130 minutes.

What is the most punctual flight time for Seattle to London flights?

Historically, flights departing at night are less likely to be delayed, whereas flights leaving in the evening tend to experience delays more often.

What day of the week experiences the fewest flight delays on this route?

Saturday tends to have the lowest number of delays on this route, whereas Thursday has historically faced a higher average of delays compared to other days of the week.

Which airline has the best punctuality record on Seattle to London flights?

Over the past year, Virgin Atlantic have had the lowest number of delays on this route, with just 5% of flights being delayed.

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

The price you pay for your flight from Seattle to London may vary depending on when you book. For the best chance of a lower fare, look to book 64 days in advance of your trip. Fares are likely to increase a fortnight or so before your departure date.

Reviews of airlines servicing London

Get a feel of what it's like to fly with Alaska Airlines and Virgin Atlantic from Seattle to London by reading reviews from past customers. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.

Related info for your journey

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Travelling 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.

Complete your trip

Complete your trip to London by adding a car hire and/or hotel booking to your travel itinerary.

Direct flights to England

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 8 October 2026.

Best flights from Seattle to London
Discover carefully curated flight deals from Seattle to London that have cost, travel time, and stopovers in mind to ensure you get the best travel experience. Data last updated 8 October 2026.

Direct flights from Seattle to London
Explore direct flight options from Seattle to London based on user searches, and compare prices and availability for your desired travel dates. Data last updated 8 October 2026.

Last-minute flights from Seattle to London
Discover last-minute flight deals from Seattle to London. Data last updated 8 October 2026 and is based on user searches.

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 8 October 2026.

Seattle to London flights typically cost between £542 and £772 in January.
The cheapest return price found within the last 5 days was £568 on United Airlines (12 Jan–13 Jan).