Cheap flights from Seattle to London

Round-trip
Economy
Seattle (SEA)
London (LON)
Depart
Return
Any month
Compare vs. Cheapflights |

The best prices from Seattle/Tacoma Intl to London are usually found in October or January, booked 60 days in advance, depart on a Tuesday or Friday and return on a Tuesday

How to find the cheapest flight from
Seattle (SEA) to London (LON)

All the information you need to plan the best SEA to LON flight in 2021: compare Seattle to London flight prices with the expected peak season, weather and rainfall in London.
SEA - LON
Price
C$ 487 - C$ 787
LON
Temperature
4 - 17 °C
LON
Precipitation
40 - 70 mm

Popular in

December

High demand for flights, 27% potential price rise

Cheapest in

October

Best time to find cheap flights, 15% potential price drop

Round-trip from

C$ 602

From Seattle/Tacoma Intl to London (LON)

One-way from

C$ 393

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

Flight route prices based on searches on Cheapflights within the last 3 days, monthly prices based on aggregated historical data.
What is the cheapest day to fly round-trip from Seattle to London?

Monday is generally a great day to depart. Flying on this day could help you save up to 8%.

When is the cheapest time to fly from Seattle to London (SEA - LON)?

It’s optimal to fly from Seattle to London in the evening. By choosing this option you can save up to 10% on the cost of your flight, compared to a flight at noon.

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

October is one of the best times of the year to fly to London from Seattle. Prices for October average C$ 711 per person but you can even find prices for as low as C$ 514. The most expensive prices can be found in the month of December. Opting for a October flight can save you 36% on your journey compared to booking in October

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

To save up to 75% on this flight, we recommend booking at least 61 days prior to travel. The price may fluctuate and will likely increase closer to your departure date. Users on Cheapflights have found tickets from Seattle to London from C$ 1,013 1-2 weeks out and tickets from C$ 1,333 for flights departing within the next 72 hours.

Cheap flights from Seattle to London in October, November 2021

The best prices found for SEA to LON flights for October, November
14 Nov - 23 Nov
C$ 792pp
SEA
Seattle/Tacoma Intl
Multiple Airlines
   
2 STOPS
LGW
London Gatwick
LGW
London Gatwick
Multiple Airlines
   
2 STOPS
SEA
Seattle/Tacoma Intl
11 Nov - 13 Nov
C$ 798pp
SEA
Seattle/Tacoma Intl
Lufthansa
   
2 STOPS
LHR
London Heathrow
LHR
London Heathrow
Lufthansa
   
2 STOPS
SEA
Seattle/Tacoma Intl
15 Nov - 13 Dec
C$ 802pp
SEA
Seattle/Tacoma Intl
Icelandair
 
1 STOP
LHR
London Heathrow
LHR
London Heathrow
Icelandair
 
1 STOP
SEA
Seattle/Tacoma Intl

Seattle/Tacoma Intl to London 2021 flight deals

Cheap flights to London from Seattle found for this year
14 Nov - 23 Nov
C$ 792pp
SEA
Seattle/Tacoma Intl
Multiple Airlines
   
2 STOPS
LGW
London Gatwick
LGW
London Gatwick
Multiple Airlines
   
2 STOPS
SEA
Seattle/Tacoma Intl
11 Nov - 13 Nov
C$ 798pp
SEA
Seattle/Tacoma Intl
Lufthansa
   
2 STOPS
LHR
London Heathrow
LHR
London Heathrow
Lufthansa
   
2 STOPS
SEA
Seattle/Tacoma Intl
15 Nov - 13 Dec
C$ 802pp
SEA
Seattle/Tacoma Intl
Icelandair
 
1 STOP
LHR
London Heathrow
LHR
London Heathrow
Icelandair
 
1 STOP
SEA
Seattle/Tacoma Intl

Direct flights to London from Seattle

Save time with Seattle to London direct flight deals
26 Dec - 13 Jan
C$ 958pp
SEA
Seattle/Tacoma Intl
British Airways
Direct
LHR
London Heathrow
LHR
London Heathrow
British Airways
Direct
SEA
Seattle/Tacoma Intl
12 Jan - 28 Jan
C$ 959pp
SEA
Seattle/Tacoma Intl
British Airways
Direct
LHR
London Heathrow
LHR
London Heathrow
British Airways
Direct
SEA
Seattle/Tacoma Intl
6 Apr - 6 May
C$ 960pp
SEA
Seattle/Tacoma Intl
British Airways
Direct
LHR
London Heathrow
LHR
London Heathrow
British Airways
Direct
SEA
Seattle/Tacoma Intl

Last minute flights from Seattle to London

Late deals on round-trip flights to London from Seattle, departing today and this week
24 Oct - 2 Nov
C$ 1,054pp
SEA
Seattle/Tacoma Intl
Icelandair
 
1 STOP
LHR
London Heathrow
LHR
London Heathrow
Icelandair
 
1 STOP
SEA
Seattle/Tacoma Intl
23 Oct - 2 Nov
C$ 1,116pp
SEA
Seattle/Tacoma Intl
Icelandair
 
1 STOP
LHR
London Heathrow
LHR
London Heathrow
Icelandair
 
1 STOP
SEA
Seattle/Tacoma Intl
23 Oct - 29 Oct
C$ 1,121pp
SEA
Seattle/Tacoma Intl
Icelandair
 
1 STOP
LGW
London Gatwick
LGW
London Gatwick
Icelandair
 
1 STOP
SEA
Seattle/Tacoma Intl

One-way flights to London from Seattle

The cheapest one-way flights from Seattle to London
7:30 a.m. - 6:20 a.m.
WestJet
1 stop
14h 50m
SEA - LGW
WestJet
C$ 393
WestJet
7:30 a.m. - 6:20 a.m.
WestJet
1 stop
14h 50m
SEA - LGW
WestJet
C$ 455
WestJet
7:30 a.m. - 6:20 a.m.
WestJet
1 stop
14h 50m
SEA - LGW
WestJet
C$ 456

Related info for your journey

Useful info, stats and facts about <span class="emphasized">Seattle</span> to <span class="emphasized">London</span> flights.

Flight FAQs

From Seattle to London

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

Most people fly from Seattle/Tacoma Intl (SEA) if they book a flight from Seattle to London. On average, Seattle/Tacoma Intl has 11 outbound flights to London per day from 9 airlines. Seattle/Tacoma Intl is conveniently located just 18.4 km from Seattle’s city centre.

Which airlines flying from Seattle/Tacoma Intl to London have flexible cancellations due to COVID-19?

Virgin Atlantic, Delta, and American Airlines are some of the carriers that may have flexible cancellation policies. You can use our site to filter for other airlines that may also have this kind of flexibility.

Can I find flights from Seattle to London for under C$ 800 on Cheapflights?

Yes, there are multiple flights from Seattle to London for under C$ 800. The cheapest flight booked recently is on Multiple Airlines for just C$ 792, but on average you can expect to pay C$ 846.

Are there direct flights from Seattle to London for under C$ 1,000 on Cheapflights?

Cheapflights has 20 direct flights from Seattle to London under C$ 1,000. A good price for a direct flight from Seattle to London is less than C$ 1,026.

Are there last-minute flights available from Seattle to London for under C$ 1,100?

There are currently 20+ open flights from Seattle to London within the next 7 days for less than C$ 1,100.

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

According to our current data, Lufthansa (C$ 798), and Icelandair (C$ 802) offers the cheapest pricing from Seattle to London.

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

Consider American Airlines, Air France or British Airways when booking your flight. These represent the most popular airlines when flying from Seattle to London.

What are the most reliable airlines from Seattle to London?

The top 3 most reliable airlines when flying from Seattle to London are Alaska Airlines (97%), American Airlines (90%) and Finnair (90%).

What are the cheapest flights from Seattle to London?

Looking at all options, your cheapest flight can be booked for C$ 514. While the most popular route (Seattle/Tacoma Intl - London Heathrow) can be booked for C$ 3,140 on average our data indicates C$ 757 when flying from Seattle to London

COVID Restrictions

View COVID Travel Restrictions for London, England

Do I need a COVID test to fly to London from Seattle?

Information is based on travel restrictions from Seattle/Tacoma Intl to London

Most visitors from Seattle/Tacoma Intl need to provide a negative COVID-19 test result and/or quarantine to enter London.

COVID-19 testing requirements
Visitors from Seattle/Tacoma Intl must present a negative RT-PCR (NAAT) or Antigen (quick-test) test taken 72 hours before departing to London.

Quarantine requirements
Visitors from Seattle/Tacoma Intl are not required to quarantine after entering London.

Documents
Mandatory passenger locator form - Submit the form any time in the 48 hours before arriving in the UK. Show the form when checking in your plane, train or ferry to the UK.

Managed quarantine package for Scotland - All travelers arriving directly to Scotland are required to book their Managed Quarantine Package prior to travel.

COVID-19 testing package - All travelers must book and pay for a COVID-19 Testing Package prior to travel to England and Scotland.


Do I need a test to fly back to Seattle from London?

Returning to Seattle/Tacoma Intl from London

COVID-19 testing requirements
Visitors from London must present a negative RT-PCR (NAAT) test taken 72 hours before departing to Seattle/Tacoma Intl.

Quarantine requirements
Visitors from London are not required to quarantine after entering Seattle/Tacoma Intl.

Hide COVID Travel Restrictions for London, England

Destination information for London

Things to know before you go - useful duration and weather info for your trip from Seattle to London.
Today's exchange rate
C$ 1 = £0.59
Average temperature for October in London
16.0 °C
Avg rainfall for October in London
71.0 mm

Airports servicing Seattle

Airports servicing London

Gatwick (LGW)
Stansted (STN)
London City (LCY)
Luton (LTN)
Southend (SEN)

Top 6 airlines flying from Seattle/Tacoma Intl to London

The chart below displays the airlines Cheapflights users travelling from Seattle to London choose most often. Cheapest and average prices are based on aggregated data from the past 12 months.
Airline Cheapest Average Flexibility On-time COVID-19 safety
American Airlines
C$ 514 C$ 721 No cancel fee 71%
Search American Airlines flights
Virgin Atlantic
C$ 519 C$ 778 No cancel fee 72%
Search Virgin Atlantic flights
Icelandair
C$ 533 C$ 659 No cancel fee 76%
Search Icelandair flights
Delta
C$ 537 C$ 701 No cancel fee N/A
Search Delta flights
Iberia
C$ 539 C$ 665 No cancel fee 77%
Search Iberia flights
British Airways
C$ 539 C$ 906 No cancel fee 70%
Search British Airways flights

Hourly flight availability from Seattle to London

See what time of day planes typically take off from Seattle towards London.
Afternoon Noon to 6 PM 50% of flight departures
Evening 6 PM to midnight 50% of flight departures
Early morning Midnight to 6 AM 0% of flight departures
Morning 6 AM to noon 0% of flight departures
Midnight
6 AM
Noon
6 PM
Weekly flight availability
from Seattle to London
See how many times per day planes take to the skies headed from Seattle to London.
Sunday
11 daily flights
Monday
11 daily flights
Tuesday
11 daily flights
Wednesday
11 daily flights
Thursday
11 daily flights
Friday
11 daily flights
Saturday
11 daily flights
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