Find Cheap Flights from Seattle/Tacoma Intl to London (SEA - LON)

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Good to Know

Low Season:
October
Best time to beat the crowds
4%
expected price decrease
High Season:
July
Most popular time to fly
22%
expected price increase
Average price:
C$ 1123
(avg. price over the last 2 weeks)
Good Deal:
C$ 690
or less (round trip)

When to Book Flights from Seattle/Tacoma Intl to London

Average price per month
Flight prices as travel date approaches
-1 day
-2 days

Top tips for Finding a Cheap Flight

Looking for a cheap flight? 25% of our users found flights on this route for C$ 690 or less.
The cheapest flight from Seattle/Tacoma Intl to London was found, on average, 69 days before departure.
Book at least 3 weeks before departure in order to get a below-average price.
High season is considered to be June, July and August. The cheapest month to fly is October.
Morning departure is around 14% cheaper than an evening flight, on average*.
*Average of the lowest prices shown in KAYAK’s search results for departures within the next 30 days

FAQs for Booking Seattle/Tacoma Intl to London Flights

How long does a flight from Seattle/Tacoma Intl to London take?
An average nonstop flight takes 9h 30m, covering a distance of 7712 km.
How many flights are there between Seattle/Tacoma Intl and London?
There are 93 (nonstop) flights between Seattle/Tacoma Intl and London per week, averaging 13 per day.
Which airlines provide the cheapest flights from Seattle/Tacoma Intl to London?
In the past 3 days, the cheapest round-trip tickets were found on Norwegian (C$ 527), Multiple Airlines (C$ 622) and British Airways (C$ 717).
Do I need a passport to fly between Seattle/Tacoma Intl and London?
Yes.
Which airlines fly most frequently between Seattle/Tacoma Intl and London?
American Airlines (1 times daily), Aer Lingus (1 times daily), Finnair (1 times daily) are the most frequent flyers on this route.
What’s the cheapest day of the week to fly from Seattle/Tacoma Intl to London?
For Seattle/Tacoma Intl to London, Wednesday is the cheapest day to fly on average and Wednesday is the most expensive. Flying from London back to Seattle/Tacoma Intl, the best deals are generally found on Tuesday, with Saturday being the most expensive.

Book cheap flights from Seattle/Tacoma Intl to London (round-trip)

Airports
Origin
Seattle
C$ 527
only
C$ 527
Destination
London
C$ 717
only
C$ 717
C$ 527
only
C$ 527
Wed, 7 Feb
SEA
LGW
9h 30m
Wed, 21 Feb
LGW
SEA
9h 55m
C$ 527
Trip: 15 days
7.1GoodShow reviews
Overall 7.1 Good
Based on 9 reviews
Boarding
7.3
Comfort
7.2
Crew
7.7
Entertainment
7.2
Food
6.4
LGW
LAX
Okay 4.3

My seat was comfortable,bathrooms were clean.

Some not all of the staff was a tad bit cooler in demanor than was needed. Too much movement by other passengers.

LGW
JFK
Mediocre 2.6

If the format is ordering food there's suppose I be a good standard of service. And there isn't. Also they didn't have earphones for sale-- if they're not handing them for free st least make sure you have some for sale.

SEA
LGW
Okay 4.3

The plane itself was quite nice.

After a 5 hour delay, we finally started boarding. We were loaded in buses and taken to the plane. When we got there they told us there were technical issues. They left the heat in the bus running at 27 C for about 10 Minutes. People were banging on the doors asking to open them. Finally they turned off the heat. It was not fun.

BOS
LGW
Excellent 10.0

The new plane was amazing and I feel so fortunate to have had the opportunity. The experience was streamlined and the technology state-of-the-art, accessible, and extremely useful. The impressive crew looked flawless and performed their duties very well. It was all quite a spectacle!

It is always really nice to get free coffee as a passenger. Traveling is exhausting and I would have been so appreciative of free coffee on the flight, and felt even more comforted and likely to fly Norwegian in the future.

JFK
LGW
Mediocre 3.3

Limited food, services, didnt sell headphones

Mon, 15 Jan
SEA
LGW
20h 50m
Fri, 26 Jan
LGW
SEA
9h 50m
C$ 622
Trip: 12 days
Overall 0.0 Poor
Based on 0 reviews
Fri, 26 Jan
SEA
LHR
38h 30m
Mon, 29 Jan
LHR
SEA
21h 08m
C$ 717
Trip: 4 days
7.7GoodShow reviews
Overall 7.7 Good
Based on 109 reviews
Overall
7.5
Boarding
7.6
Comfort
7.2
Crew
8.0
Entertainment
7.0
Food
6.9
SEA
LHR
Okay 4.3

3 hours on the plain waiting for take off. Cheap sandwich for breakfast.

SEA
LHR
Excellent 9.3

So nice to be able to lie down fir the long distances. The food was quite good for airplane fare.

Where do they get these movies? Surely there are good movies that are a few years old they could offer.

SEA
LHR
Good 6.6

Friendly attendants, good food and great movie selection. All flights on time!

Very crowded - seats are so close. I’m 5 feet 8 inches and normal weight and was squished!

SEA
LHR
Mediocre 3.0

The flight attendants were all very nice. The flight was on time.

I'm told (late) that BA does not subscribe to TSA prep in the USA. That meant going to the TSA line first, being rejected, going back to check-in to know the reason, then back to the standard long line. Once onboard my seat's entertainment system dies not work. 3 reset attempted with no luck. A month ago, on another long haul flight the same happened. Food was very bad. Salmon so overdone that it was hard to cut, overcooked vegetables and some lukewarm mash potatoes.

SEA
LHR
Mediocre 2.0

Flight was fine

Delayed due to inclement weather for 4 hours then lost the baggage

Sat, 13 Jan
SEA
LGW
17h 20m
Mon, 22 Jan
LGW
SEA
18h 40m
C$ 793
Trip: 10 days
8.1ExcellentShow reviews
Overall 8.1 Excellent
Based on 962 reviews
Overall
8.1
Boarding
8.3
Comfort
7.8
Crew
8.5
Entertainment
8.0
Food
7.8
SFO
LHR
Mediocre 2.0

Flight was cancelled .

LAX
LHR
Good 6.0

good plane and timing

meal was not served according to the request and no sound support from the staff

LHR
JFK
Okay 5.0

Quite a big choice of movies and TV shows to watch, more than enough for an eight hour flight. Normal headphone plugs so you can use your own.

I booked together with my wife, yet we were allocated seats apart and were not able to be reassigned together. The leg room was so tight that I could not pick up things off the floor without putting my head in the next persons lap. Though the cabin crew were smiley and friendly, it was hard to get their attention when needed. The PA system is much louder than the entertainment, so announcements were ear bursting. The dinner selections ran out early, so a good proportion did not get their choice.

CHC
BNE
Excellent 9.6

The crew were very friendly and attentive through out flight.

EWR
LHR
Okay 5.0

The entertainment selection was good, though I didn't need to see the blurb about having vloggers available before every movie. One of the very few airlines to use boarding by rows, which speeds up the boarding process.

The legroom is very cramped, pretty difficult to eat your meal with the seat in front reclined. The crew were not very attentive: they completely missed me while I was waving the rubbish on their collection rounds. In the end I had to dump it myself in the toilet bins. The PA system is too loud compared to the rest of the entertainment, had to remove the headphones for each one of them.

Wed, 7 Feb
SEA
LGW
16h 58m
Wed, 21 Feb
LGW
SEA
9h 55m
C$ 632
Trip: 15 days
Overall 0.0 Poor
Based on 0 reviews
Wed, 17 Jan
SEA
LGW
35h 33m
Wed, 24 Jan
LGW
SEA
9h 55m
C$ 646
Trip: 8 days
Overall 0.0 Poor
Based on 0 reviews
Thu, 22 Feb
SEA
LHR
42h 40m
Sun, 25 Feb
LHR
SEA
43h 15m
C$ 758
Trip: 4 days
7.7GoodShow reviews
Overall 7.7 Good
Based on 109 reviews
Overall
7.5
Boarding
7.6
Comfort
7.2
Crew
8.0
Entertainment
7.0
Food
6.9
SEA
LHR
Mediocre 2.0

I was not allowed to board, because I was told I needed a Turkish Visa, even to change planes, and may have lost my ticket payment.

SEA
LHR
Mediocre 3.0

The flight attendants were all very nice. The flight was on time.

I'm told (late) that BA does not subscribe to TSA prep in the USA. That meant going to the TSA line first, being rejected, going back to check-in to know the reason, then back to the standard long line. Once onboard my seat's entertainment system dies not work. 3 reset attempted with no luck. A month ago, on another long haul flight the same happened. Food was very bad. Salmon so overdone that it was hard to cut, overcooked vegetables and some lukewarm mash potatoes.

SEA
LHR
Okay 4.0

The flight was cancelled, it was very difficult for me to do all rearrangements.

SEA
LHR
Okay 4.3

3 hours on the plain waiting for take off. Cheap sandwich for breakfast.

SEA
LHR
Excellent 8.0

The crew was really nice overall and the entertainment system was adequate. The main meal was decent too.

The flight was late (I was warned online but there was denial at the airport and gate) and further delayed in flight so I missed my connection. I didn't like the pods in business class. I had a forward facing seat at least, which are all by the aisles. They seemed narrow. I didn't sleep (never do). The breakfast was a bit lame. Getting into buses from the plane IS lame. It took a while to get to the terminal.

Mon, 15 Jan
SEA
LGW
17h 20m
Thu, 18 Jan
LGW
SEA
18h 45m
C$ 793
Trip: 4 days
8.1ExcellentShow reviews
Overall 8.1 Excellent
Based on 962 reviews
Overall
8.1
Boarding
8.3
Comfort
7.8
Crew
8.5
Entertainment
8.0
Food
7.8
EWR
LHR
Okay 5.0

The entertainment selection was good, though I didn't need to see the blurb about having vloggers available before every movie. One of the very few airlines to use boarding by rows, which speeds up the boarding process.

The legroom is very cramped, pretty difficult to eat your meal with the seat in front reclined. The crew were not very attentive: they completely missed me while I was waving the rubbish on their collection rounds. In the end I had to dump it myself in the toilet bins. The PA system is too loud compared to the rest of the entertainment, had to remove the headphones for each one of them.

SFO
LHR
Mediocre 2.0

Flight was cancelled .

LAX
LHR
Good 6.0

good plane and timing

meal was not served according to the request and no sound support from the staff

CHC
BNE
Excellent 9.6

The crew were very friendly and attentive through out flight.

LHR
JFK
Okay 5.0

Quite a big choice of movies and TV shows to watch, more than enough for an eight hour flight. Normal headphone plugs so you can use your own.

I booked together with my wife, yet we were allocated seats apart and were not able to be reassigned together. The leg room was so tight that I could not pick up things off the floor without putting my head in the next persons lap. Though the cabin crew were smiley and friendly, it was hard to get their attention when needed. The PA system is much louder than the entertainment, so announcements were ear bursting. The dinner selections ran out early, so a good proportion did not get their choice.

Mon, 15 Jan
SEA
LGW
20h 50m
Wed, 7 Feb
LGW
SEA
9h 55m
C$ 662
Trip: 24 days
Overall 0.0 Poor
Based on 0 reviews
Wed, 4 Apr
SEA
LGW
17h 25m
Wed, 18 Apr
LGW
SEA
18h 31m
C$ 798
Trip: 15 days
8.1ExcellentShow reviews
Overall 8.1 Excellent
Based on 962 reviews
Overall
8.1
Boarding
8.3
Comfort
7.8
Crew
8.5
Entertainment
8.0
Food
7.8
SFO
LHR
Mediocre 2.0

Flight was cancelled .

LAX
MEL
Excellent 8.0

I like flying Virgin whether Australia or Atlantic!

Just a little bit more leg room.

MEL
LAX
Good 6.6

The flight crew from the mel to lax route were excellent. One was especially attentive to my 2 toddlers and gave me a bit of a break, something that has NEVER happened in over 40 flights traveling with children.

I think something was broken in our section (mel to lax) as it was uncomfortably hot and the flight crew tried to get it cooler but could not. I’ve never experienced a flight that was too hot, usually the opposite. It was stifling.

BWI
DTW
Mediocre 3.3

The crew was rude.

EWR
LHR
Okay 5.0

The entertainment selection was good, though I didn't need to see the blurb about having vloggers available before every movie. One of the very few airlines to use boarding by rows, which speeds up the boarding process.

The legroom is very cramped, pretty difficult to eat your meal with the seat in front reclined. The crew were not very attentive: they completely missed me while I was waving the rubbish on their collection rounds. In the end I had to dump it myself in the toilet bins. The PA system is too loud compared to the rest of the entertainment, had to remove the headphones for each one of them.

Wed, 7 Feb
SEA
LGW
16h 58m
Mon, 12 Feb
LGW
SEA
9h 50m
C$ 662
Trip: 6 days
Overall 0.0 Poor
Based on 0 reviews
Wed, 2 May
SEA
LGW
17h 25m
Wed, 9 May
LGW
SEA
18h 31m
C$ 798
Trip: 8 days
8.1ExcellentShow reviews
Overall 8.1 Excellent
Based on 962 reviews
Overall
8.1
Boarding
8.3
Comfort
7.8
Crew
8.5
Entertainment
8.0
Food
7.8
BWI
DTW
Mediocre 3.3

The crew was rude.

LGW
UVF
Excellent 8.0

The flight was a good flight overall. I was able to relax on the flight because I had the option of paying for a seat with more leg space. The cabin crew was pleasant and quite helpful

I didn’t like the fact that I had to pay for extra leg space. I’ve travelled with other airlines and had to option to choose my seat without any additional charge

DTW
LHR
Good 7.6

Excellent entertainment options, out stewardess was fantastic.

Cramped seats.

LAX
BNE
Excellent 10.0

Very polite and helpful staff.

LAX
MEL
Excellent 8.0

I like flying Virgin whether Australia or Atlantic!

Just a little bit more leg room.

Wed, 24 Jan
SEA
LGW
35h 33m
Mon, 29 Jan
LGW
SEA
9h 50m
C$ 664
Trip: 6 days
Overall 0.0 Poor
Based on 0 reviews
Tue, 6 Feb
SEA
LGW
22h 15m
Tue, 20 Feb
LGW
SEA
32h 11m
C$ 671
Trip: 15 days
Overall 0.0 Poor
Based on 0 reviews
Thu, 25 Jan
SEA
LGW
20h 50m
Wed, 31 Jan
LGW
SEA
9h 55m
C$ 677
Trip: 7 days
Overall 0.0 Poor
Based on 0 reviews
Wed, 21 Feb
SEA
LGW
35h 35m
Wed, 7 Mar
LGW
SEA
9h 55m
C$ 689
Trip: 15 days
Overall 0.0 Poor
Based on 0 reviews
Mon, 15 Jan
SEA
LGW
20h 50m
Sat, 20 Jan
LGW
SEA
14h 52m
C$ 697
Trip: 6 days
Overall 0.0 Poor
Based on 0 reviews
Sat, 3 Mar
SEA
LGW
32h 05m
Tue, 13 Mar
LGW
SEA
26h 11m
C$ 707
Trip: 10 days
Overall 0.0 Poor
Based on 0 reviews
Wed, 21 Feb
SEA
LGW
35h 35m
Wed, 28 Feb
LGW
SEA
9h 55m
C$ 709
Trip: 8 days
Overall 0.0 Poor
Based on 0 reviews
Wed, 7 Feb
SEA
LGW
16h 58m
Mon, 19 Feb
LGW
SEA
9h 50m
C$ 711
Trip: 13 days
Overall 0.0 Poor
Based on 0 reviews
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The fares displayed include all taxes and fees for economy class travel and were found by the provider in the last 72 hours. Seats are limited and may not be available on all flights and days. Fares are subject to change and may not be available on all flights or dates of travel. Some carriers charge additional fees for extra checked bags. Please check the carriers' sites.