How long is the flight from Seattle to London?

Airlines like Scandinavian Airlines, Virgin Atlantic, and Delta fly from Seattle to London in about 16h 20m. The time it takes to get you to your destination can typically vary by up to 2h 15m. 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 £456. Other airlines that can offer you cheap pricing are Alaska Airlines, from £487, and Virgin Atlantic, from £494. British Airways is currently priced 27% 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 £1,117. The most popular route, (Seattle/Tacoma Intl - London Heathrow), can usually be booked for £419.

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 16 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.

£227+ 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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Best

Direct

Last-minute

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 1 September 2026.

Fri 25/915:55 -

1 stop16h 05m

Tue 6/1006:40 -

1 stop15h 05m

Deal found 26/8£545

Sun 11/1015:40 -

3 stops33h 55m

Sun 18/1010:35 -

3 stops18h 05m

Deal found 26/8£546

Sun 11/1019:00 -

2 stops17h 10m

Sun 18/1009:20 -

2 stops19h 20m

Deal found 28/8£547

Tue 6/1015:55 -

1 stop16h 05m

Wed 21/1007:05 -

2 stops23h 59m

Deal found 28/8£547

Sat 10/1015:55 -

2 stops17h 05m

Sun 11/1019:30 -

2 stops34h 28m

Deal found 26/8£548

Mon 19/1018:55 -

1 stop13h 05m

Fri 23/1007:40 -

1 stop17h 30m

Deal found 27/8£548

Tue 22/915:55 -

1 stop17h 45m

Sat 10/1006:40 -

2 stops15h 05m

Deal found 31/8£549

Fri 25/915:55 -

2 stops20h 35m

Fri 2/1008:10 -

1 stop13h 35m

Deal found 26/8£550

Sun 4/1015:55 -

1 stop18h 35m

Tue 13/1007:05 -

2 stops23h 59m

Deal found 27/8£550

Wed 14/1019:00 -

2 stops18h 40m

Mon 19/1021:25 -

1 stop28h 30m

Deal found 26/8£551

Sun 11/1015:55 -

1 stop21h 45m

Sat 24/1006:40 -

2 stops21h 54m

Deal found 27/8£551

Wed 30/914:30 -

2 stops23h 10m

Sun 4/1007:05 -

1 stop14h 40m

Deal found 30/8£552

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 1 September 2026.

Mon 5/1005:50 -

3 stops21h 10m

Tue 13/1005:40 -

2 stops19h 19m

Deal found 28/8£554

Fri 9/1015:55 -

2 stops18h 35m

Fri 16/1006:40 -

2 stops24h 09m

Deal found 28/8£564

Wed 20/115:25 -

1 stop16h 20m

Wed 27/110:00 -

1 stop13h 13m

Deal found 28/8£643

Mon 5/1021:50 -

Nonstop9h 45m

Wed 14/1011:45 -

1 stop12h 50m

Deal found 30/8£667

Wed 13/118:55 -

Nonstop9h 25m

Sun 24/114:45 -

Nonstop10h 05m

Deal found 31/8£675

Wed 7/1007:00 -

2 stops21h 35m

Tue 13/1019:15 -

2 stops31h 17m

Deal found 28/8£692

Thu 4/219:05 -

1 stop30h 50m

Sun 14/217:20 -

1 stop31h 50m

Deal found 26/8£695

Sat 17/1019:15 -

1 stop34h 05m

Sat 24/1007:30 -

2 stops18h 07m

Deal found 27/8£720

Thu 15/1013:45 -

1 stop11h 45m

Thu 22/1009:20 -

1 stop15h 15m

Deal found 29/8£725

Sun 18/1015:40 -

1 stop15h 00m

Mon 16/1111:55 -

1 stop13h 05m

Deal found 30/8£729

Sun 6/1214:35 -

1 stop16h 30m

Sun 13/1206:00 -

1 stop19h 00m

Deal found 31/8£577

Sun 13/915:55 -

2 stops16h 30m

Thu 17/907:05 -

2 stops24h 15m

Deal found 28/8£594

Mon 19/1019:00 -

2 stops19h 05m

Tue 3/1107:00 -

3 stops22h 57m

Deal found 30/8£577

Sun 13/915:55 -

2 stops17h 05m

Sat 19/906:40 -

2 stops23h 23m

Deal found 28/8£612

Wed 13/115:25 -

1 stop16h 20m

Sun 24/110:00 -

1 stop13h 13m

Deal found 29/8£682

Sun 18/1013:30 -

1 stop11h 55m

Wed 18/1110:00 -

2 stops21h 00m

Deal found 30/8£682

Mon 19/1007:00 -

2 stops17h 40m

Wed 18/1109:15 -

2 stops19h 32m

Deal found 30/8£699

Wed 4/1120:05 -

1 stop29h 50m

Tue 10/1117:20 -

1 stop31h 50m

Deal found 26/8£700

Thu 5/1119:05 -

1 stop32h 45m

Mon 9/1111:05 -

2 stops42h 44m

Deal found 31/8£720

Wed 4/1118:55 -

Nonstop9h 25m

Mon 9/1114:45 -

Nonstop10h 05m

Deal found 29/8£725

Wed 14/1015:40 -

2 stops17h 00m

Fri 30/1006:55 -

2 stops18h 05m

Deal found 30/8£613

Wed 4/1115:25 -

1 stop16h 20m

Tue 10/1110:00 -

2 stops20h 55m

Deal found 26/8£683

Wed 20/107:20 -

2 stops24h 40m

Wed 27/118:40 -

2 stops35h 40m

Deal found 28/8£625

Wed 4/1115:35 -

2 stops17h 30m

Tue 10/1119:05 -

2 stops33h 42m

Deal found 29/8£699

Mon 19/1019:15 -

1 stop30h 40m

Wed 4/1110:55 -

1 stop39h 15m

Deal found 27/8£700

Wed 28/1016:20 -

1 stop16h 25m

Sun 8/1110:00 -

1 stop13h 14m

Deal found 31/8£712

Mon 5/1017:45 -

1 stop16h 45m

Tue 13/1020:15 -

1 stop23h 37m

Deal found 28/8£687

Sun 8/1116:15 -

2 stops21h 40m

Sun 15/1118:40 -

2 stops29h 15m

Deal found 27/8£625

Tue 3/1107:24 -

2 stops24h 36m

Thu 12/1118:40 -

2 stops36h 15m

Deal found 29/8£635

Thu 15/1019:15 -

1 stop30h 40m

Fri 20/1117:20 -

1 stop31h 50m

Deal found 30/8£702

Find flight deals from Seattle to London

Round-trip from	£545
One-way from	£227
Popular in	June
Cheapest in	January
Average price	£655
Good round-trip deal	£667 or less
Good one-way deal	£266 or less

Scandinavian Airlines
25/9-6/10
2 total stops
31h 10m total
Seattle to London

Search Deals

25/10
2 total stops
19h 35m total
Seattle to London

Search Deals

Highest demand for flights based on searches. 19% potential increase in price (£110 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 September 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 - LTN London Luton

SEALTN

Seattle/Tacoma Intl

Mon 5/10

05:50-11:00

3 stops21h 10m

London Luton

Tue 13/10

05:40-16:59

2 stops19h 19m

£554

SeattleLondon

SEA Seattle/Tacoma Intl - LHR London Heathrow

SEALHR

Seattle/Tacoma Intl

Fri 9/10

15:55-18:30

2 stops18h 35m

London Heathrow

Fri 16/10

06:40-22:49

2 stops24h 09m

£564

SeattleLondon

SEA Seattle/Tacoma Intl - LTN London Luton

SEALTN

Seattle/Tacoma Intl

Sun 6/12

14:35-15:05

1 stop16h 30m

London Luton

Sun 13/12

06:00-17:00

1 stop19h 00m

£577

SeattleLondon

SEA Seattle/Tacoma Intl - LTN London Luton

SEALTN

Seattle/Tacoma Intl

Mon 19/10

19:00-22:05

2 stops19h 05m

London Luton

Tue 3/11

07:00-21:57

3 stops22h 57m

£577

SeattleLondon

SEA Seattle/Tacoma Intl - LHR London Heathrow

SEALHR

Seattle/Tacoma Intl

Sun 13/9

15:55-16:25

2 stops16h 30m

London Heathrow

Thu 17/9

07:05-23:20

2 stops24h 15m

£594

SeattleLondon

SEA Seattle/Tacoma Intl - LHR London Heathrow

SEALHR

Seattle/Tacoma Intl

Sun 13/9

15:55-17:00

2 stops17h 05m

London Heathrow

Sat 19/9

06:40-22:03

2 stops23h 23m

£612

SeattleLondon

SEA Seattle/Tacoma Intl - SEN London Southend

SEASEN

Seattle/Tacoma Intl

Wed 14/10

15:40-16:40

2 stops17h 00m

London Southend

Fri 30/10

06:55-18:00

2 stops18h 05m

£613

SeattleLondon

SEA Seattle/Tacoma Intl - LTN London Luton

SEALTN

Seattle/Tacoma Intl

Sun 8/11

16:15-21:55

2 stops21h 40m

London Luton

Sun 15/11

18:40-15:55

2 stops29h 15m

£625

SeattleLondon

SEA Seattle/Tacoma Intl - LHR London Heathrow

SEALHR

Seattle/Tacoma Intl

Wed 20/1

07:20-16:00

2 stops24h 40m

London Heathrow

Wed 27/1

18:40-22:20

2 stops35h 40m

£625

SeattleLondon

SEA Seattle/Tacoma Intl - LHR London Heathrow

SEALHR

Seattle/Tacoma Intl

Tue 3/11

07:24-16:00

2 stops24h 36m

London Heathrow

Thu 12/11

18:40-22:55

2 stops36h 15m

£635

Flights are sorted by cheapest return flights first.

Deals found on 31/8

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-LGW

SEA-LHR

SEA-LTN

SEA-STN

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-LGW

SEA-LHR

SEA-LTN

SEA-STN

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 £478). 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 Monday (24 on average). You will have fewer flight options on Thursday, which is when the least amount of flights are scheduled (13 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 £526 and £751 in September.
The cheapest return price found within the last 5 days was £545 on Scandinavian Airlines (25 Sept–6 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 Reykjavik (KEF) 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 139 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 51 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

12,863 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

12,863 reviews

Alaska Airlines

7.9

Good

12,863 reviews

Check prices

Reviews

1 / 20

6.0

Good

Anonymous,Jul 2026

SEA - LHR

KLM

7.8

Good

1,569 reviews

Alaska Airlines

7.9

Good

12,863 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

12,863 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 16 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, Virgin Atlantic, and Delta fly from Seattle to London in about 16h 20m. The time it takes to get you to your destination can typically vary by up to 2h 15m. 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 £456. Other airlines that can offer you cheap pricing are Alaska Airlines, from £487, and Virgin Atlantic, from £494. British Airways is currently priced 27% 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 £1,117. The most popular route, (Seattle/Tacoma Intl - London Heathrow), can usually be booked for £419.
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 £478). 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.

See more FAQs

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Top 3 airlines flying from Seattle to London

Airline	Cheapest	Average	Flexibility	On-time
British Airways	Cheapest£456	Average£675	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£607	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 £227

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 25/10. 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 1 September 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 1 September 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 1 September 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 1 September 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 1 September 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 1 September 2026.

Last-minute flights from Seattle to LondonDiscover last-minute flight deals from Seattle to London. Data last updated 1 September 2026 and is based on user searches.

Discover last-minute flight deals from Seattle to London. Data last updated 1 September 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 1 September 2026.

Search for one-way flight options from Seattle to London. Find affordable one-way fares based on user searches. Data last updated 1 September 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 1 September 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 1 September 2026.

The most flights from SEA to LON are scheduled on a Monday (24 on average). You will have fewer flight options on Thursday, which is when the least amount of flights are scheduled (13 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 £526 and £751 in September.The cheapest return price found within the last 5 days was £545 on Scandinavian Airlines (25 Sept–6 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 Reykjavik (KEF) 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 139 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 51 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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Can I find deals for flights from Seattle to London that include hotel bookings?

How can I find direct flights from Seattle to London?

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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 1 September 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 1 September 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 1 September 2026.

Last-minute flights from Seattle to London
Discover last-minute flight deals from Seattle to London. Data last updated 1 September 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 1 September 2026.

Seattle to London flights typically cost between £526 and £751 in September.
The cheapest return price found within the last 5 days was £545 on Scandinavian Airlines (25 Sept–6 Oct).