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

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

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

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 stopovers 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 Seattle/Tacoma Intl Airport to London.

What documentation or ID do you need to fly to London?

The travel and health documents required for your trip to London can vary based on your itinerary and personal situation. As a rule, consider having multiple documents such as a national ID card or driver’s licence, and a passport valid for six-months after you plan to arrive at London. We always recommend checking with your airline or a trusted third party such as IATA to get advice.

R26 644 Cheap Flights from Seattle to London in 2025/26

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How to get the cheapest flight ticket from Seattle to London

Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip

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What is the cheapest month to fly to London?

The month of October is, on average, the cheapest month to fly to London from Seattle, with most prices found around R11 591. If you are unable to visit London during the month of October, then departing from Seattle during the month August is also very affordable. Most momondo users find prices during this month for around R11 836.

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

The cheapest time of day to fly to London is in the evening when flights can be purchased for as low as R27 943. Try not to purchase tickets in the afternoon because they tend to be around R32 379. Of course, these prices can vary depending on the time of year and what airport you fly to.

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

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

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

You are more likely to see cheaper flights to London from Seattle when booking weeks ahead of your departure date. In general, you can expect to find flights to London for around R14 055 when searching weeks before you fly. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to London from Seattle for as low as R12 325 on momondo.

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

There is only 1 cabin class available to choose from on Seattle/Tacoma Intl to London flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.

How have Seattle to London flight prices changed over time?

As of October 2025, prices for Seattle to London flights are approximately 36% cheaper when compared to flights at the same time last year.

When to book flights from Seattle to London

Are you open to changing your travel dates? Check out the ideal times to fly from Seattle to London according to our flight data. Find out which month and days have the cheapest flights.

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

Find info about flight duration, direct flights, and airports for your flight from Seattle to London

Best price found	R27 532
Direct flights	None

The best flight deal from Seattle to London found on momondo in the last 72 hours is R27 532

There are no direct flights from Seattle to London. Popular non-direct route for this connection is Seattle/Tacoma Intl Airport - London Heathrow Airport.

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How far is Seattle/Tacoma Intl to London by plane?
There are 7694,7 km between Seattle/Tacoma Intl and London.
When did momondo last update prices for flights from Seattle/Tacoma Intl Airport to London?
Prices for flights from Seattle/Tacoma Intl Airport to London refresh daily.
How old do you have to be to fly from Seattle/Tacoma Intl Airport to London?
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 stopovers 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 Seattle/Tacoma Intl Airport to London.
What documentation or ID do you need to fly to London?
The travel and health documents required for your trip to London can vary based on your itinerary and personal situation. As a rule, consider having multiple documents such as a national ID card or driver’s licence, and a passport valid for six-months after you plan to arrive at London. We always recommend checking with your airline or a trusted third party such as IATA to get advice.
What is the most popular plane model from Seattle to London?
Based on momondo bookings for this flight route, the most popular plane model on flight routes from Seattle to London is Boeing 787-10 Dreamliner (29,34% of total bookings). The next most popular plane models are Airbus A330-900neo (17,23%), Airbus A330-200 (15,97%), and Boeing 787-9 Dreamliner (13,41%).

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Why use momondo?

Why should I use momondo to find a flight deal from Seattle to London?

It is quick and easy to find Seattle to London flights on momondo. We search and return numerous flight options from various airlines and agents. You can then use our filters to narrow your search until you have found the most convenient flight to London that suits you.

Can I find flights from Seattle to London with flexible booking policies on momondo?

Yes. momondo allows you to filter the results for Seattle to London flights to just show those with flexible booking policies.

How can momondo help me find flights from Seattle to London?

Once you have performed a search for Seattle to London flights, momondo helps you find the right one by offering useful filters to narrow down your flight selection. Flights can be filtered by multiple factors such as airline, airport and price; but also by other criteria like aircraft type and payment method.

I’m not ready to book a flight from Seattle to London right now. Can momondo alert me if prices change?

Price alerts on flights to London from Seattle are quick and easy to set up on momondo. Simply perform a search and select the price alert feature. It is as simple as that.