Question 1

What is the cheapest London to Seattle/Tacoma Intl flight route?

Accepted Answer

Fly from London Heathrow to Seattle/Tacoma Intl for the best London - Seattle/Tacoma Intl flight prices

Question 2

How many flights depart from London to Seattle on average per week?

Accepted Answer

The number of flights available between London and Seattle is 79 per week as of December 2025. The most frequent departure day is Thu, with 19% of weekly flights leaving on this day.

Question 3

Which stopover airport offers the lowest fares from London to Seattle?

Accepted Answer

Flights via Frankfurt am Main (FRA) offer the lowest average return price of £397.

Question 4

How often are flights from London to Seattle delayed?

Accepted Answer

Historically, on average around 13% of flights between London and Seattle have experienced a delay on any given week. The average delay length over the past 12 months has been 119 minutes.

Question 5

What is the cheapest time of day to depart on your flight to Seattle?

Accepted Answer

According to our data, the cheapest time of day to fly to Seattle is in the evening. momondo users have found flights departing from London to Seattle in the evening for as low as £527. Keep in mind that these prices may fluctuate based on what airline you choose and the time of year you plan to travel. Flights in the morning are often more expensive, with an average ticket price of £622.

Question 6

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

Accepted Answer

You are more likely to see cheaper flights to Seattle from London when booking weeks ahead of your departure date. In general, you can expect to find flights to Seattle for around £569 when searching weeks before you fly. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Seattle from London for as low as £522 on momondo.

Question 7

How have London to Seattle flight prices changed over time?

Accepted Answer

As of December 2025, prices for London to Seattle flights are approximately 15% more expensive when compared to flights at the same time last year.

Question 8

Can stopping save me money on London to Seattle flights?

Accepted Answer

You could potentially save up to 17% on your flight if you consider stops on a London to Seattle flight.

Question 9

Which stopover airport has the shortest connection time from London to Seattle?

Accepted Answer

Munich (MUC) has the shortest average stopover time for this route: 1h 25m.

Question 10

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

Accepted Answer

Generally, flights departing in the evening tend to experience fewer delays. Flights departing in the early afternoon have, in the past, seen delays more frequently in comparison.

Question 11

What cabin class options are available on London to Seattle/Tacoma Intl flights?

Accepted Answer

There are 4 cabin classes available to choose from on London to Seattle/Tacoma Intl flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.

Question 12

What is the cheapest month to fly to Seattle?

Accepted Answer

The cheapest month to fly to Seattle from London is in January. Flight prices, which tend to average around £485, are often lower during this time because this is during the off-season. The month of February is another great option to travel to Seattle, with average flight prices from London averaging around £490.

Question 13

Which airport is the most popular for stopovers for flights between London and Seattle?

Accepted Answer

Reykjavik (KEF) was the most common stop: 72% of momondo users choosing one-stop flights on this route connected there.

Question 14

What day of the week experiences the fewest flight delays on this route?

Accepted Answer

Tuesday is statistically the day of the week that experiences the fewest delays on this flight route. Wednesday has historically seen more delays on average compared to the rest of the week.

Question 15

What is the cheapest airline that flies from London to Seattle/Tacoma Intl?

Accepted Answer

United Airlines, SWISS, and KLM are the most popular carriers operating from London to Seattle/Tacoma Intl

Question 16

Which airlines fly to Seattle?

Accepted Answer

Virgin Atlantic, British Airways and Icelandair are the top three most popular airlines that fly to Seattle from London according to our data. Virgin Atlantic is the first choice among our users, with 50% of people opting to fly with this airline when travelling to Seattle. Keep in mind that there are 14 different airlines that fly to Seattle on a routine basis, so you have a few additional options to choose from.

Question 17

Which stopover airport has the shortest travel time from London to Seattle?

Accepted Answer

Flights connecting via Reykjavik (KEF) have the shortest average one-way travel time: 12h 59m.

Question 18

What is the cheapest day to depart on your flight to Seattle?

Accepted Answer

According to our data, Wednesday is the cheapest day to fly to Seattle from London. The lowest ticket price found for a Wednesday departure recently was £588. Keep in mind that prices can always vary depending on your route and whether or not you are flying domestic or international. Be sure to avoid booking your departure on a Sunday as prices are generally higher than usual. According to our data, the average ticket price to Seattle on Sunday is £667.

Question 19

Which airline has the best punctuality record on London to Seattle flights?

Accepted Answer

According to our data, Delta have had the fewest delays on this route over the last 12 months, with about 6% of their flights experiencing any sort of delay.

Question 20

How many flights depart from London to Seattle on average per day?

Accepted Answer

The number of flights available between London and Seattle is 11 per day as of December 2025. The most frequent departure time is 14:00, with 80% of daily flights leaving in the afternoon.

Question 21

Which airlines fly direct from London to Seattle?

Accepted Answer

If you're looking for a non-stop flight from London to Seattle, there are currently two airlines that offer direct flights: British Airways and Delta Air Lines. Both airlines operate daily flights between the two cities, providing a convenient option for travellers who want to reach Seattle quickly and efficiently. British Airways operates direct flights from London Heathrow Airport (LHR) to Seattle-Tacoma International Airport (SEA), with a flight time of approximately 9h 45min. Delta Air Lines, on the other hand, operates direct flights from London Gatwick Airport (LGW) to SEA, with a flight time of approximately 9h 15min. If you're willing to take a connecting flight, several other airlines operate flights between London and Seattle with layovers, including Icelandair, Air France, KLM, and Lufthansa. These airlines typically have layovers in cities such as Reykjavik, Paris, Amsterdam, or Frankfurt.

What is the best way to get in and out of airports in London and Seattle?

Getting to and from London's airports is relatively easy and convenient. London Heathrow Airport (LHR) and London Gatwick Airport (LGW) are both well-connected to the city centre by public transport, taxi, and rideshare services. For LHR, the fastest and most convenient way to get to the airport is by taking the Heathrow Express, which runs from London Paddington Station to Heathrow Airport in just 15 minutes. Alternatively, you can take the London Underground, the Piccadilly Line connects directly with Heathrow terminals 1-5. If you prefer a more comfortable and convenient option, taxis and rideshare services are also available from various points in the city. For LGW, the Gatwick Express is a popular choice, providing a fast and direct link to the airport from London Victoria Station. The journey takes around 30 minutes. Alternatively, you can take the Thameslink train, which connects Gatwick Airport with central London and beyond, or take a taxi or a rideshare service. When it comes to getting from Seattle-Tacoma International Airport (SEA) to downtown Seattle, there are several transportation options available, including taxis, rideshare services, and the Sound Transit Light Rail. The Light Rail provides an affordable and efficient way to reach downtown Seattle and other destinations, with a journey time of approximately 40 minutes. Hire cars are also available at the airport, with several major car rental companies operating at the airport.

What are the benefits of the different airports in London and Seattle?

London is served by several airports, each with its own advantages and disadvantages. London Heathrow (LHR) is the largest and busiest airport in the UK, offering excellent connectivity to destinations worldwide. London Gatwick (LGW) is another popular airport, particularly for travellers heading to destinations in Europe and beyond. London City Airport (LCY) is the closest airport to central London, providing quick and easy access to the city's financial district. Seattle-Tacoma International Airport (SEA) is the largest airport in the Pacific Northwest region of the United States, providing easy access to Seattle and the surrounding area. The airport is well-equipped with modern facilities and a range of amenities, including restaurants, shops, and lounges. The airport has 5 lounges that include The Club at SEA, Delta Sky Club, Alaska Lounge, United Club and Centurion Lounge. Some other benefits to SEA include its focus on sustainable practises and being the leader in innovation, which is known for its innovative approaches to improving the passenger experience.

Which cities can you get to from Seattle Airport?

Seattle-Tacoma International Airport (SEA) is the largest airport in the Pacific Northwest and offers flights to many destinations both domestically and internationally. The airport is a hub for Alaska Airlines and Delta Air Lines and also serves a number of other airlines. Domestically, passengers can fly non-stop to many major US cities, including Los Angeles, San Francisco, New York, Boston, Atlanta, and Chicago, among others. There are also a number of flights to smaller regional airports throughout the Pacific Northwest, such as Portland, Eugene, and Spokane. Internationally, SEA offers direct flights to several destinations in Asia, including Tokyo, Seoul, Beijing, and Shanghai. There are also direct flights to Europe, with destinations such as London and Paris. Other international destinations include Canada, Mexico, and the Caribbean.

Question 22

When did momondo last update prices for flights from London to Seattle/Tacoma Intl Airport?

Accepted Answer

Prices for flights from London to Seattle/Tacoma Intl Airport are updated daily.

Question 23

How many operators does momondo search for flights from London to Seattle/Tacoma Intl Airport?

Accepted Answer

As of December 2025, there are 14 operators available to choose from for flights from London to Seattle/Tacoma Intl Airport.

Question 24

How old do you have to be to fly from London to Seattle/Tacoma Intl Airport?

Accepted Answer

The minimum age for a child to fly alone is five, but airlines that offer an unaccompanied minor (UNMR) service may have their own age limitations. Flight duration, scheduling, and layovers are among the considerations that may influence age limits. We recommend that you double-check with the airline you are booking with for travel from London to Seattle/Tacoma Intl Airport.

Question 25

What documentation or ID do you need to fly to Seattle/Tacoma Intl Airport?

Accepted Answer

The travel and health documents you'll need for your trip to Seattle/Tacoma Intl Airport may differ based on your itinerary and personal situation. Typically, you should have several documents on hand, such as a national ID card or driver's license and a passport that is valid for six months after your intended arrival at Seattle/Tacoma Intl Airport. It is always advisable to seek advice from your airline or a trusted third party, such as IATA.

Best price found	£461
Fastest flight time	9h 45m
Direct flights	Every day
Airports in Seattle	1 airport

Airline	Rating	Free Cancellation	Price
Icelandair	PriceFrom £326	Free Cancellation	Rating 7.0 589 reviews	Search Icelandair flights
Air France	PriceFrom £386	Free Cancellation	Rating 7.4 1,504 reviews	Search Air France flights
Lufthansa	PriceFrom £396	Free Cancellation	Rating 6.8 7,626 reviews	Search Lufthansa flights
Finnair	PriceFrom £398	Free Cancellation	Rating 7.6 1,334 reviews	Search Finnair flights
KLM	PriceFrom £400	Free Cancellation	Rating 7.7 1,432 reviews	Search KLM flights
United Airlines	PriceFrom £406	Free Cancellation	Rating 7.4 9,095 reviews	Search United Airlines flights
Aer Lingus	PriceFrom £418	Free Cancellation	Rating 7.2 1,394 reviews	Search Aer Lingus flights
British Airways	PriceFrom £438	Free Cancellation	Rating 6.7 7,571 reviews	Search British Airways flights
Virgin Atlantic	PriceFrom £442	Free Cancellation	Rating 7.5 675 reviews	Search Virgin Atlantic flights
Delta	PriceFrom £446	Free Cancellation	Rating 7.9 8,009 reviews	Search Delta flights

Cheap flights from London to Seattle from £396

This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from London to Seattle departing on 3/6. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.

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How to get the cheapest flight ticket from London to Seattle

What is the cheapest month to fly to Seattle?

What is the cheapest day to depart on your flight to Seattle?

What is the cheapest time of day to depart on your flight to Seattle?

What is the cheapest London to Seattle/Tacoma Intl flight route?

Fly from London Heathrow to Seattle/Tacoma Intl for the best London - Seattle/Tacoma Intl flight prices

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

What cabin class options are available on London to Seattle/Tacoma Intl flights?

There are 4 cabin classes available to choose from on London to Seattle/Tacoma Intl flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.

Can stopping save me money on London to Seattle flights?

You could potentially save up to 17% on your flight if you consider stops on a London to Seattle flight.

How have London to Seattle flight prices changed over time?

As of December 2025, prices for London to Seattle flights are approximately 15% more expensive when compared to flights at the same time last year.

What is the cheapest airline that flies from London to Seattle/Tacoma Intl?

United Airlines, SWISS, and KLM are the most popular carriers operating from London to Seattle/Tacoma Intl

Which airlines fly to Seattle?

How often are flights from London to Seattle delayed?

Historically, on average around 13% of flights between London and Seattle have experienced a delay on any given week. The average delay length over the past 12 months has been 119 minutes.

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

Generally, flights departing in the evening tend to experience fewer delays. Flights departing in the early afternoon have, in the past, seen delays more frequently in comparison.

What day of the week experiences the fewest flight delays on this route?

Tuesday is statistically the day of the week that experiences the fewest delays on this flight route. Wednesday has historically seen more delays on average compared to the rest of the week.

Which airline has the best punctuality record on London to Seattle flights?

According to our data, Delta have had the fewest delays on this route over the last 12 months, with about 6% of their flights experiencing any sort of delay.

Which airport is the most popular for stopovers for flights between London and Seattle?

Reykjavik (KEF) was the most common stop: 72% of momondo users choosing one-stop flights on this route connected there.

Which stopover airport offers the lowest fares from London to Seattle?

Flights via Frankfurt am Main (FRA) offer the lowest average return price of £397.

Which stopover airport has the shortest travel time from London to Seattle?

Flights connecting via Reykjavik (KEF) have the shortest average one-way travel time: 12h 59m.

Which stopover airport has the shortest connection time from London to Seattle?

Munich (MUC) has the shortest average stopover time for this route: 1h 25m.

How many flights depart from London to Seattle on average per day?

The number of flights available between London and Seattle is 11 per day as of December 2025. The most frequent departure time is 14:00, with 80% of daily flights leaving in the afternoon.

How many flights depart from London to Seattle on average per week?

The number of flights available between London and Seattle is 79 per week as of December 2025. The most frequent departure day is Thu, with 19% of weekly flights leaving on this day.

When to book flights from London to Seattle

Cheap London to Seattle (LON to SEA) flight deals and tips

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How old do you have to be to fly from London to Seattle/Tacoma Intl Airport?

What documentation or ID do you need to fly to Seattle/Tacoma Intl Airport?

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What is the most popular airline from London to Seattle?

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