How long is the flight from Seattle to London?

Airlines like United Airlines, Delta, and Icelandair fly from Seattle to London in about 9h 30m. The time it takes to get you to your destination can typically vary by up to 9h 05m. 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 £345. Other airlines that can offer you cheap pricing are British Airways, from £349, and Virgin Atlantic, from £364. Aer Lingus is currently priced 38% 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 WestJet, with whom users have recently found tickets for as low as £238. However, be on the lookout for offers from JetBlue and SWISS, as they are both options that can get you from Seattle to London for a low price.

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

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

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 City.

What are the cheapest flights from Seattle to London?

The cheapest flight price from Seattle to London is £278. On average you can expect to pay £873. The most popular route, (Seattle/Tacoma Intl - London Heathrow), can usually be booked for £347.

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 Aeromexico (88%), KLM (87%) or Air France (87%) 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 British Airways, Aer Lingus and Icelandair. Something to consider prior to booking your flight.

What is the cheapest day to fly round-trip from Seattle to London?

Flying to your destination on a Thursday can be more expensive, but this shouldn’t discourage you from finding affordable options to get to London. Check prices with Cheapflights to find a great deal for your trip.

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

Travelers have found it’s best to book a flight 52 days in advance to save up to 41% compared to booking the same week of travel. As your travel date approaches, the cost of this flight route may potentially increase. While opting to book 52 days out may not be an option for all, there are still additional ways to secure a deal in the near future. You might find a flight from Seattle to London 1-2 weeks in advance for as low as £472, or £686 for flights within the next 24 hours.

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

The best pricing can be found in the month of October. Prices to London from Seattle average £558. You can even find prices in October for less than £558, as users have found deals to London from as low as £379. The month of June appears to be one of the more expensive times to travel to London from Seattle. Flying in the targeted month can save you up to 32%.

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 20 outbound flights to London per day. You should also have plenty of airline options to choose from since 4 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.

£195+ Flights from Seattle to London

Cheapflights Tip: The best prices from Seattle/Tacoma Intl to London are usually found in October or August, booked 51 days in advance, depart on a Tuesday or Wednesday and return on a Wednesday

Cheap flight deals from Seattle to London

Round-trip from	£374
One-way from	£195
Popular in	June
Cheapest in	October
Average price	£513
Good round-trip deal	£486 or less
Good one-way deal	£342 or less

1/10-8/10
4 total stops
43h 10m total
Seattle to London

Search Deals

14/10
2 total stops
18h 30m total
Seattle to London

Search Deals

Highest demand for flights based on searches. 15% potential increase in price (£74 potential increase over avg. return price).

Search Deals

Cheapest flight prices on average. 2% potential price decrease (£12 potential savings vs. average return price).

Search Deals

Average for round-trip flights in September 2025

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

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 16 September 2025.

Wed 1/1015:45SEA - STN

2 stops22h 45mMultiple Airlines

Wed 8/1008:15STN - SEA

2 stops20h 25mMultiple Airlines

Deal found 14/9£374

Fri 24/1019:00SEA - LGW

1 stop11h 40mIcelandair

Sun 2/1111:55LGW - SEA

1 stop13h 05mIcelandair

Deal found 14/9£374

Mon 22/917:35SEA - LHR

Nonstop9h 45mVirgin Atlantic

Tue 7/1017:35LHR - SEA

1 stop25h 40mVirgin Atlantic

Deal found 15/9£374

Wed 12/1116:48SEA - LHR

Nonstop9h 42mDelta

Wed 19/1106:20LHR - SEA

1 stop15h 00mDelta

Deal found 16/9£375

Wed 12/1116:48SEA - LHR

Nonstop9h 42mDelta

Tue 18/1106:20LHR - SEA

1 stop13h 05mDelta

Deal found 13/9£375

Thu 6/1114:35SEA - LGW

1 stop12h 20mIcelandair

Wed 19/1111:55LGW - SEA

1 stop13h 05mIcelandair

Deal found 15/9£376

Tue 14/1020:25SEA - LHR

Nonstop9h 50mDelta

Thu 23/1006:30LHR - SEA

1 stop17h 35mDelta

Deal found 15/9£376

Wed 1/1013:30SEA - LHR

Nonstop9h 20mBritish Airways

Tue 14/1009:25LHR - SEA

Nonstop9h 45mBritish Airways

Deal found 14/9£377

Wed 8/1007:15SEA - LHR

1 stop15h 15mAir Canada

Tue 14/1006:50LHR - SEA

2 stops22h 55mAir Canada

Deal found 14/9£377

Mon 1/1214:35SEA - LGW

2 stops18h 45mMultiple Airlines

Sun 14/1208:25LGW - SEA

2 stops16h 35mMultiple Airlines

Deal found 15/9£378

Wed 1/1011:25SEA - LHR

1 stop14h 35mDelta

Tue 4/1106:20LHR - SEA

1 stop13h 05mDelta

Deal found 14/9£378

Fri 7/1114:35SEA - LHR

1 stop12h 15mIcelandair

Sat 15/1112:15LHR - SEA

1 stop12h 45mIcelandair

Deal found 13/9£379

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 16 September 2025.

Tue 3/308:30SEA - LHR

2 stops18h 35mUnited Airlines

Wed 11/313:25LHR - SEA

2 stops40h 04mUnited Airlines

Deal found 15/9£375

Tue 28/1020:20SEA - LHR

Nonstop9h 30mDelta

Tue 11/1106:20LHR - SEA

1 stop13h 05mDelta

Deal found 14/9£375

Mon 27/1019:50SEA - LHR

Nonstop9h 30mBritish Airways

Tue 11/1109:25LHR - SEA

Nonstop10h 05mBritish Airways

Deal found 15/9£380

Fri 7/1114:35SEA - LGW

1 stop12h 20mIcelandair

Sat 15/1111:55LGW - SEA

1 stop13h 05mIcelandair

Deal found 13/9£381

Fri 3/1015:45SEA - LTN

2 stops16h 00mMultiple Airlines

Mon 6/1009:00LTN - SEA

2 stops16h 50mMultiple Airlines

Deal found 13/9£385

Tue 3/306:05SEA - LCY

2 stops18h 45mVirgin Atlantic

Wed 15/417:50LCY - SEA

1 stop25h 45mVirgin Atlantic

Deal found 14/9£439

Mon 27/1017:45SEA - LHR

Nonstop9h 45mDelta

Tue 11/1106:20LHR - SEA

1 stop13h 05mDelta

Deal found 15/9£375

Mon 9/319:50SEA - LHR

Nonstop9h 30mBritish Airways

Thu 26/314:55LHR - SEA

Nonstop10h 00mBritish Airways

Deal found 15/9£380

Sun 9/1114:35SEA - LGW

1 stop12h 20mIcelandair

Fri 21/1111:55LGW - SEA

1 stop13h 05mIcelandair

Deal found 15/9£381

Thu 30/1015:35SEA - STN

2 stops15h 40mMultiple Airlines

Thu 6/1108:05STN - SEA

2 stops16h 55mMultiple Airlines

Deal found 14/9£386

Sun 2/1116:48SEA - LHR

Nonstop9h 42mDelta

Tue 11/1106:20LHR - SEA

1 stop13h 05mDelta

Deal found 14/9£375

Tue 4/1114:35SEA - LGW

1 stop12h 20mIcelandair

Wed 19/1111:55LGW - SEA

1 stop13h 05mIcelandair

Deal found 15/9£381

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 16 September 2025.

Wed 1/1013:30SEA - LHR

Nonstop9h 20mBritish Airways

Tue 14/1009:25LHR - SEA

Nonstop9h 45mBritish Airways

Deal found 14/9£377

Wed 4/318:50SEA - LHR

Nonstop9h 30mFinnair

Tue 10/309:25LHR - SEA

Nonstop10h 05mFinnair

Deal found 15/9£377

Mon 2/318:50SEA - LHR

Nonstop9h 30mFinnair

Tue 10/314:55LHR - SEA

Nonstop10h 00mFinnair

Deal found 15/9£378

Sun 15/218:50SEA - LHR

Nonstop9h 30mFinnair

Wed 25/214:55LHR - SEA

Nonstop10h 00mFinnair

Deal found 14/9£380

Wed 1/1020:25SEA - LHR

Nonstop9h 50mDelta

Fri 10/1018:00LHR - SEA

Nonstop10h 25mDelta

Deal found 16/9£380

Tue 18/1119:20SEA - LHR

Nonstop9h 30mDelta

Thu 27/1112:20LHR - SEA

Nonstop10h 28mDelta

Deal found 16/9£381

Tue 3/313:25SEA - LHR

Nonstop9h 35mFinnair

Wed 15/416:30LHR - SEA

Nonstop9h 50mFinnair

Deal found 14/9£389

Tue 3/313:25SEA - LHR

Nonstop9h 35mBritish Airways

Wed 1/409:50LHR - SEA

Nonstop9h 45mBritish Airways

Deal found 15/9£393

Fri 10/1020:25SEA - LHR

Nonstop9h 50mVirgin Atlantic

Tue 14/1017:25LHR - SEA

Nonstop10h 25mVirgin Atlantic

Deal found 16/9£411

Thu 9/1013:30SEA - LHR

Nonstop9h 20mBritish Airways

Thu 16/1009:50LHR - SEA

Nonstop9h 45mBritish Airways

Deal found 14/9£414

Wed 11/218:50SEA - LHR

Nonstop9h 30mFinnair

Sat 21/209:25LHR - SEA

Nonstop10h 05mFinnair

Deal found 14/9£414

Tue 14/1013:30SEA - LHR

Nonstop9h 20mBritish Airways

Mon 20/1009:50LHR - SEA

Nonstop9h 45mBritish Airways

Deal found 14/9£415

Last-minute flights from Seattle to London
Discover last-minute flight deals from Seattle to London. Data last updated 16 September 2025 and is based on user searches.

Mon 22/917:35SEA - LHR

Nonstop9h 45mVirgin Atlantic

Tue 7/1017:35LHR - SEA

1 stop25h 40mVirgin Atlantic

Deal found 15/9£374

Mon 29/920:25SEA - LHR

Nonstop9h 50mDelta

Fri 10/1006:15LHR - SEA

1 stop13h 00mDelta

Deal found 16/9£375

Tue 30/920:25SEA - LHR

Nonstop9h 50mDelta

Thu 9/1009:00LHR - SEA

1 stop16h 40mDelta

Deal found 15/9£375

Wed 1/1013:30SEA - LHR

Nonstop9h 20mBritish Airways

Tue 14/1009:25LHR - SEA

Nonstop9h 45mBritish Airways

Deal found 14/9£377

Wed 1/1011:25SEA - LHR

1 stop14h 35mDelta

Tue 4/1106:20LHR - SEA

1 stop13h 05mDelta

Deal found 14/9£378

Wed 1/1020:25SEA - LHR

Nonstop9h 50mDelta

Fri 10/1018:00LHR - SEA

Nonstop10h 25mDelta

Deal found 16/9£380

Sat 4/1017:26SEA - LHR

1 stop33h 44mUnited Airlines

Tue 14/1017:40LHR - SEA

1 stop36h 05mUnited Airlines

Deal found 15/9£380

Sun 5/1007:50SEA - LHR

1 stop16h 15mDelta

Tue 14/1011:45LHR - SEA

1 stop32h 05mDelta

Deal found 14/9£379

Wed 8/1007:15SEA - LHR

1 stop15h 15mAir Canada

Tue 14/1006:50LHR - SEA

2 stops22h 55mAir Canada

Deal found 14/9£377

Mon 13/1019:00SEA - LGW

1 stop11h 35mIcelandair

Sun 26/1014:40LGW - SEA

1 stop34h 20mIcelandair

Deal found 15/9£376

Tue 14/1020:25SEA - LHR

Nonstop9h 50mDelta

Thu 23/1006:30LHR - SEA

1 stop17h 35mDelta

Deal found 15/9£376

Fri 24/1019:00SEA - LGW

1 stop11h 40mIcelandair

Sun 2/1111:55LGW - SEA

1 stop13h 05mIcelandair

Deal found 14/9£374

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 16 September 2025.

Tue 14/1014:05SEA - STN

2 stops18h 30mMultiple Airlines

Deal found 14/9£195

Tue 14/1014:05SEA - LTN

2 stops24h 05mMultiple Airlines

Deal found 14/9£195

Sat 4/1021:39SEA - LHR

2 stops40h 21mMultiple Airlines

Deal found 14/9£195

Thu 23/1013:50SEA - STN

2 stops18h 50mMultiple Airlines

Deal found 14/9£196

Sun 16/1117:45SEA - LHR

3 stops35h 05mMultiple Airlines

Deal found 14/9£196

Sun 15/215:10SEA - LHR

1 stop13h 40mWestJet

Deal found 15/9£197

Fri 14/1115:10SEA - LHR

1 stop13h 40mWestJet

Deal found 14/9£198

Thu 16/1008:40SEA - STN

2 stops20h 50mMultiple Airlines

Deal found 14/9£199

Thu 30/1010:08SEA - LHR

2 stops24h 22mMultiple Airlines

Deal found 16/9£199

Fri 17/1013:50SEA - LGW

3 stops35h 35mWestJet

Deal found 14/9£199

Fri 28/1105:50SEA - LHR

3 stops23h 00mMultiple Airlines

Deal found 14/9£199

Tue 7/1014:05SEA - STN

2 stops18h 30mMultiple Airlines

Deal found 15/9£200

Fly from

Fly to

Route

Depart

Return

Price

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Tue 3/3

08:30-11:05

2 stops18h 35m

London Heathrow

Wed 11/3

13:25-22:29

2 stops40h 04m

£375

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Tue 28/10

20:20-12:50

Nonstop9h 30m

London Heathrow

Tue 11/11

06:20-11:25

1 stop13h 05m

£375

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Mon 27/10

17:45-10:30

Nonstop9h 45m

London Heathrow

Tue 11/11

06:20-11:25

1 stop13h 05m

£375

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Sun 2/11

16:48-10:30

Nonstop9h 42m

London Heathrow

Tue 11/11

06:20-11:25

1 stop13h 05m

£375

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Wed 1/10

11:25-09:15

1 stop13h 50m

London Heathrow

Wed 5/11

06:20-13:20

1 stop15h 00m

£378

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Tue 25/11

12:20-10:55

1 stop14h 35m

London Heathrow

Thu 4/12

06:30-11:50

1 stop13h 20m

£379

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Mon 27/10

19:50-12:20

Nonstop9h 30m

London Heathrow

Tue 11/11

09:25-11:30

Nonstop10h 05m

£380

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Mon 9/3

19:50-12:20

Nonstop9h 30m

London Heathrow

Thu 26/3

14:55-17:55

Nonstop10h 00m

£380

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Mon 29/9

17:35-11:20

Nonstop9h 45m

London Heathrow

Fri 10/10

18:00-20:25

Nonstop10h 25m

£380

SeattleLondon

SEA - LGW

SEALGW

Seattle/Tacoma Intl

Fri 7/11

14:35-10:55

1 stop12h 20m

London Gatwick

Sat 15/11

11:55-17:00

1 stop13h 05m

£381

Flights are sorted by cheapest return flights first.

Deals found on 14/9

Showing 1-10 of 60 results

...

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 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

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.

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 £112). Flying from Seattle to London in August is currently the most expensive (average of £164). 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 at midday could potentially save you up to 43% on airfare.

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 stopover airport for flights from Seattle to London?

Reykjavik (KEF) – chosen by Cheapflights users on 64% 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 £439.

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 40m.

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 28m.

Reviews of airlines servicing London

Get a feel of what it's like to fly with KLM, Virgin Atlantic, andIcelandair 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.

KLM

7.8

Good

1,385 reviews

Check prices

Reviews

1 / 20

4.0

Okay

Mark,Sept 2025

AMS - BHX

Crew and snacks were good, boarding wasn't great as busses were used rather than boarding tunnels. Also endured a one hour delay.

KLM

7.8

Good

1,385 reviews

KLM

7.8

Good

1,385 reviews

Check prices

Reviews

1 / 20

4.0

Okay

Mark,Sept 2025

AMS - BHX

Crew and snacks were good, boarding wasn't great as busses were used rather than boarding tunnels. Also endured a one hour delay.

Virgin Atlantic

7.4

Good

664 reviews

KLM

7.8

Good

1,385 reviews

Check prices

Reviews

1 / 20

4.0

Okay

Mark,Sept 2025

AMS - BHX

Crew and snacks were good, boarding wasn't great as busses were used rather than boarding tunnels. Also endured a one hour delay.

Icelandair

7.0

Good

544 reviews

KLM

7.8

Good

1,385 reviews

Check prices

Reviews

1 / 20

4.0

Okay

Mark,Sept 2025

AMS - BHX

Crew and snacks were good, boarding wasn't great as busses were used rather than boarding tunnels. Also endured a one hour delay.

Iberia

7.0

Good

2,924 reviews

KLM

7.8

Good

1,385 reviews

Check prices

Reviews

1 / 20

4.0

Okay

Mark,Sept 2025

AMS - BHX

Crew and snacks were good, boarding wasn't great as busses were used rather than boarding tunnels. Also endured a one hour delay.

British Airways

6.7

Okay

7,361 reviews

KLM

7.8

Good

1,385 reviews

Check prices

Reviews

1 / 20

4.0

Okay

Mark,Sept 2025

AMS - BHX

Crew and snacks were good, boarding wasn't great as busses were used rather than boarding tunnels. Also endured a one hour delay.

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 20 outbound flights to London per day. You should also have plenty of airline options to choose from since 4 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, Delta, and Icelandair fly from Seattle to London in about 9h 30m. The time it takes to get you to your destination can typically vary by up to 9h 05m. 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 £345. Other airlines that can offer you cheap pricing are British Airways, from £349, and Virgin Atlantic, from £364. Aer Lingus is currently priced 38% 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 WestJet, with whom users have recently found tickets for as low as £238. However, be on the lookout for offers from JetBlue and SWISS, 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 City.
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 Aeromexico (88%), KLM (87%) or Air France (87%) 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 £278. On average you can expect to pay £873. The most popular route, (Seattle/Tacoma Intl - London Heathrow), can usually be booked for £347.
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 £112). Flying from Seattle to London in August is currently the most expensive (average of £164). 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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Alternative routes for Seattle to London

Top 4 airlines flying from Seattle to London

Airline	Cheapest	Average	Flexibility	On-time
Aer Lingus	Cheapest£345	Average£505	FlexibilityNo cancel fee	On-timeN/A	Search Aer Lingus flights
British Airways	Cheapest£349	Average£674	FlexibilityNo cancel fee	On-time70%	Search British Airways flights
Virgin Atlantic	Cheapest£364	Average£589	FlexibilityNo cancel fee	On-time72%	Search Virgin Atlantic flights
Icelandair	Cheapest£406	Average£563	FlexibilityNo cancel fee	On-time76%	Search Icelandair 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 £195

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 14/10. Fares are subject to change and may not be available on all flights or dates of travel.

Cheapflights Tip: The best prices from Seattle/Tacoma Intl to London are usually found in October or August, booked 51 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 16 September 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 16 September 2025.

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

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 return flight from Seattle to London. Price data was last updated on 12 September 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 16 September 2025.

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 16 September 2025.

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.

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.

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.

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.

Reviews of airlines servicing London

Get a feel of what it's like to fly with KLM, Virgin Atlantic, andIcelandair 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

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?

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.

Top 4 airlines flying from Seattle to London

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Find the best flight deals on Cheapflights, where travellers can enjoy low prices and a wide availability of flights to their desired destinations.

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

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

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

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

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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 16 September 2025.