How long is the flight from Seattle to London?

Airlines like Scandinavian Airlines, Icelandair, and Turkish Airlines fly from Seattle to London in about 12h 15m. The time it takes to get you to your destination can typically vary by up to 25h. The distance from Seattle to London is about 4783 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 £457. Other airlines that can offer you cheap pricing are Alaska Airlines, from £487, and Virgin Atlantic, from £494. British Airways is currently priced 26% 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 £126. 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 £556. The most popular route, (Seattle/Tacoma Intl - London Heathrow), can usually be booked for £401.

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 SAUDIA (97%), Scandinavian Airlines (90%) or KLM (88%) 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, British Airways and Alaska Airlines. 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 22 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.

£210+ Cheap Flights from Seattle to London

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

Cheap flight deals from Seattle to London

Enter your travel dates to find the best prices.

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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 19 August 2026.

Fri 25/915:55 -

1 stop15h 30m

Fri 2/1006:20 -

1 stop15h 25m

Deal found 16/8£479

Tue 6/1015:55 -

1 stop14h 40m

Tue 13/1007:10 -

2 stops20h 54m

Deal found 16/8£479

Sun 15/1114:35 -

2 stops17h 45m

Sun 22/1121:05 -

3 stops27h 55m

Deal found 14/8£479

Fri 2/1015:55 -

1 stop12h 45m

Fri 9/1006:20 -

1 stop15h 25m

Deal found 17/8£481

Sat 3/1015:55 -

1 stop16h 05m

Sat 10/1006:40 -

2 stops15h 05m

Deal found 19/8£481

Tue 29/907:16 -

2 stops19h 49m

Tue 6/1007:10 -

1 stop14h 35m

Deal found 14/8£482

Sun 4/1015:55 -

1 stop15h 45m

Sat 10/1005:55 -

1 stop15h 50m

Deal found 16/8£482

Sun 6/1208:21 -

2 stops15h 44m

Thu 24/1212:15 -

1 stop12h 45m

Deal found 15/8£484

Fri 2/1015:55 -

2 stops18h 35m

Fri 9/1014:45 -

3 stops31h 00m

Deal found 17/8£485

Sun 4/1015:55 -

2 stops19h 20m

Fri 9/1007:05 -

1 stop14h 40m

Deal found 19/8£485

Tue 22/915:55 -

1 stop14h 40m

Wed 30/907:00 -

2 stops24h 20m

Deal found 18/8£486

Sun 27/915:55 -

1 stop15h 45m

Sun 4/1007:05 -

1 stop14h 40m

Deal found 15/8£488

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 19 August 2026.

Sun 27/915:55 -

2 stops20h 00m

Mon 12/1006:40 -

2 stops24h 09m

Deal found 18/8£575

Sun 18/1015:40 -

1 stop12h 15m

Tue 10/1120:35 -

1 stop28h 25m

Deal found 19/8£587

Tue 15/1214:35 -

1 stop16h 30m

Tue 22/1207:00 -

1 stop18h 00m

Deal found 18/8£588

Sat 28/1119:05 -

1 stop32h 45m

Fri 11/1206:35 -

1 stop14h 25m

Deal found 14/8£630

Thu 19/1119:05 -

1 stop37h 15m

Tue 24/1117:20 -

1 stop31h 50m

Deal found 15/8£650

Mon 30/1114:35 -

1 stop21h 00m

Mon 7/1217:50 -

1 stop26h 00m

Deal found 15/8£651

Tue 20/1017:30 -

Nonstop9h 50m

Tue 10/1111:45 -

1 stop32h 02m

Deal found 19/8£666

Sat 19/921:40 -

Nonstop9h 25m

Fri 25/917:00 -

Nonstop10h 00m

Deal found 14/8£725

Fri 18/913:50 -

1 stop11h 40m

Mon 21/909:20 -

1 stop15h 15m

Deal found 16/8£761

Sun 4/1019:10 -

1 stop14h 10m

Tue 13/1009:10 -

1 stop16h 00m

Deal found 18/8£851

Mon 31/807:00 -

2 stops17h 25m

Fri 4/909:25 -

2 stops22h 01m

Deal found 14/8£1,156

Sun 27/908:00 -

2 stops22h 35m

Mon 12/1020:35 -

3 stops25h 47m

Deal found 18/8£589

Thu 29/1010:51 -

2 stops22h 09m

Sat 7/1117:00 -

2 stops37h 03m

Deal found 15/8£624

Mon 14/918:10 -

2 stops17h 45m

Mon 21/920:35 -

2 stops27h 05m

Deal found 16/8£590

Mon 16/1119:05 -

1 stop30h 50m

Mon 30/1110:55 -

1 stop38h 15m

Deal found 14/8£680

Mon 30/1110:12 -

2 stops21h 33m

Mon 7/1210:00 -

2 stops21h 59m

Deal found 15/8£686

Mon 16/1114:49 -

2 stops19h 41m

Sun 22/1119:30 -

2 stops34h 34m

Deal found 17/8£624

Mon 21/917:45 -

1 stop14h 55m

Wed 30/908:25 -

1 stop16h 10m

Deal found 15/8£687

Thu 3/918:15 -

1 stop31h 25m

Sun 6/906:50 -

2 stops23h 53m

Deal found 14/8£734

Thu 17/918:05 -

2 stops22h 45m

Thu 24/905:40 -

2 stops18h 20m

Deal found 18/8£607

Wed 13/119:05 -

1 stop30h 50m

Mon 18/110:55 -

1 stop38h 15m

Deal found 14/8£680

Tue 17/1114:49 -

2 stops19h 41m

Sun 22/1119:30 -

2 stops34h 34m

Deal found 19/8£625

Sun 27/913:50 -

1 stop19h 30m

Mon 12/1019:00 -

1 stop24h 52m

Deal found 17/8£690

Wed 21/1017:30 -

Nonstop9h 50m

Sat 31/1006:30 -

1 stop13h 17m

Deal found 15/8£703

Mon 21/919:15 -

1 stop37h 35m

Mon 5/1010:50 -

1 stop38h 30m

Deal found 16/8£682

Mon 7/1214:35 -

1 stop19h 50m

Mon 14/1207:45 -

2 stops22h 19m

Deal found 18/8£696

Mon 14/917:30 -

Nonstop9h 50m

Sun 20/918:30 -

Nonstop10h 23m

Deal found 14/8£725

Sun 13/1214:35 -

1 stop16h 30m

Sat 26/1207:00 -

1 stop18h 00m

Deal found 18/8£669

Sun 27/919:15 -

1 stop30h 40m

Mon 12/1010:50 -

1 stop38h 30m

Deal found 18/8£687

Thu 28/108:25 -

2 stops17h 05m

Thu 18/220:05 -

1 stop23h 42m

Deal found 18/8£699

Find flight deals from Seattle to London

Round-trip from	£479
One-way from	£210
Popular in	June
Cheapest in	January
Average price	£640
Good round-trip deal	£677 or less
Good one-way deal	£276 or less

25/9-2/10
2 total stops
30h 55m total
Seattle to London

Search Deals

4/10
2 total stops
30h 10m total
Seattle to London

Search Deals

Highest demand for flights based on searches. 20% potential increase in price (£116 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 August 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

Sun 27/9

15:55-19:55

2 stops20h 00m

London Heathrow

Mon 12/10

06:40-22:49

2 stops24h 09m

£575

SeattleLondon

SEA Seattle/Tacoma Intl - LHR London Heathrow

SEALHR

Seattle/Tacoma Intl

Sun 18/10

15:40-11:55

1 stop12h 15m

London Heathrow

Tue 10/11

20:35-17:00

1 stop28h 25m

£587

SeattleLondon

SEA Seattle/Tacoma Intl - LTN London Luton

SEALTN

Seattle/Tacoma Intl

Tue 15/12

14:35-15:05

1 stop16h 30m

London Luton

Tue 22/12

07:00-17:00

1 stop18h 00m

£588

SeattleLondon

SEA Seattle/Tacoma Intl - LTN London Luton

SEALTN

Seattle/Tacoma Intl

Sun 27/9

08:00-14:35

2 stops22h 35m

London Luton

Mon 12/10

20:35-14:22

3 stops25h 47m

£589

SeattleLondon

SEA Seattle/Tacoma Intl - LTN London Luton

SEALTN

Seattle/Tacoma Intl

Mon 14/9

18:10-19:55

2 stops17h 45m

London Luton

Mon 21/9

20:35-15:40

2 stops27h 05m

£590

SeattleLondon

SEA Seattle/Tacoma Intl - LTN London Luton

SEALTN

Seattle/Tacoma Intl

Thu 17/9

18:05-00:50

2 stops22h 45m

London Luton

Thu 24/9

05:40-16:00

2 stops18h 20m

£607

SeattleLondon

SEA Seattle/Tacoma Intl - LHR London Heathrow

SEALHR

Seattle/Tacoma Intl

Thu 29/10

10:51-16:00

2 stops22h 09m

London Heathrow

Sat 7/11

17:00-22:03

2 stops37h 03m

£624

SeattleLondon

SEA Seattle/Tacoma Intl - LHR London Heathrow

SEALHR

Seattle/Tacoma Intl

Mon 16/11

14:49-18:30

2 stops19h 41m

London Heathrow

Sun 22/11

19:30-22:04

2 stops34h 34m

£624

SeattleLondon

SEA Seattle/Tacoma Intl - LHR London Heathrow

SEALHR

Seattle/Tacoma Intl

Tue 17/11

14:49-18:30

2 stops19h 41m

London Heathrow

Sun 22/11

19:30-22:04

2 stops34h 34m

£625

SeattleLondon

SEA Seattle/Tacoma Intl - LHR London Heathrow

SEALHR

Seattle/Tacoma Intl

Sat 28/11

19:05-11:50

1 stop32h 45m

London Heathrow

Fri 11/12

06:35-13:00

1 stop14h 25m

£630

Flights are sorted by cheapest return flights first.

Deals found on 14/8

Showing 1-10 of 60 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-STN

SEA-LGW

SEA-LHR

SEA-LTN

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-STN

SEA-LGW

SEA-LHR

SEA-LTN

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 £476). Flying from Seattle to London in June is currently the most expensive (average of £895). 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 Sunday, which is when the least amount of flights are scheduled (19 on average).

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

Airfare is below average for this route at the moment.

Seattle to London flights typically cost between £526 and £729 in September.
The cheapest return price found within the last 5 days was £479 on Multiple Airlines (25 Sept–2 Oct).

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

Reykjavik (KEF) – chosen by Cheapflights users on 45% 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 £369.

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

Flights via Dublin (DUB) have the shortest average one-way travel time for one-stop routes: 11h 55m.

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 134 minutes.

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

Historically, flights departing in the early afternoon 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 Wednesday 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 6% 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,KLM, andVirgin 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

12,813 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

12,813 reviews

Alaska Airlines

7.9

Good

12,813 reviews

Check prices

Reviews

1 / 20

6.0

Good

Anonymous,Jul 2026

SEA - LHR

KLM

7.8

Good

1,560 reviews

Alaska Airlines

7.9

Good

12,813 reviews

Check prices

Reviews

1 / 20

6.0

Good

Anonymous,Jul 2026

SEA - LHR

Virgin Atlantic

7.4

Good

695 reviews

Alaska Airlines

7.9

Good

12,813 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 22 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 Scandinavian Airlines, Icelandair, and Turkish Airlines fly from Seattle to London in about 12h 15m. The time it takes to get you to your destination can typically vary by up to 25h. The distance from Seattle to London is about 4783 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 £457. Other airlines that can offer you cheap pricing are Alaska Airlines, from £487, and Virgin Atlantic, from £494. British Airways is currently priced 26% 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 £126. 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 SAUDIA (97%), Scandinavian Airlines (90%) or KLM (88%) 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 £556. The most popular route, (Seattle/Tacoma Intl - London Heathrow), can usually be booked for £401.
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 £476). Flying from Seattle to London in June is currently the most expensive (average of £895). 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
British Airways	Cheapest£457	Average£676	FlexibilityNo cancel fee	On-time70%	Search British Airways flights
Alaska Airlines	Cheapest£487	Average£725	FlexibilityNo cancel fee	On-time75%	Search Alaska Airlines flights
Virgin Atlantic	Cheapest£494	Average£619	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 £210

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 4/10. 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 19 August 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 19 August 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 19 August 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 19 August 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 19 August 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 19 August 2026.

Last-minute flights from Seattle to LondonDiscover last-minute flight deals from Seattle to London. Data last updated 19 August 2026 and is based on user searches.

Discover last-minute flight deals from Seattle to London. Data last updated 19 August 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 19 August 2026.

Search for one-way flight options from Seattle to London. Find affordable one-way fares based on user searches. Data last updated 19 August 2026.

Find flight deals from Seattle to London

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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 19 August 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 19 August 2026.

The most flights from SEA to LON are scheduled on a Tuesday (25 on average). You will have fewer flight options on Sunday, which is when the least amount of flights are scheduled (19 on average).

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

Airfare is below average for this route at the moment.

Seattle to London flights typically cost between £526 and £729 in September.The cheapest return price found within the last 5 days was £479 on Multiple Airlines (25 Sept–2 Oct).

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 45% 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 £369.

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 Dublin (DUB) have the shortest average one-way travel time for one-stop routes: 11h 55m.

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 134 minutes.

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

Historically, flights departing in the early afternoon 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 Wednesday 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 6% 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,KLM, andVirgin 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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What are the cheapest airlines flying from Seattle to London round-trip?

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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?

Travelling to a place near London?

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Alternative routes for Seattle to London

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Complete your trip

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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 19 August 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 19 August 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 19 August 2026.

Last-minute flights from Seattle to London
Discover last-minute flight deals from Seattle to London. Data last updated 19 August 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 19 August 2026.

Seattle to London flights typically cost between £526 and £729 in September.
The cheapest return price found within the last 5 days was £479 on Multiple Airlines (25 Sept–2 Oct).