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

According to our current data, British Airways (£475), Air France (£476), and Virgin Atlantic (£478) offers the cheapest pricing from London Heathrow Airport to Seattle. British Airways is priced at 17% lower than the current average price of a flight leaving 3 months from now.

What are the cheapest airlines to fly from London Heathrow Airport to Seattle one-way?

The cheapest airline one-way is Aer Lingus, with whom users have recently found tickets for as low as £392. However, be on the lookout for offers from Scandinavian Airlines and British Airways, as they are both options that can get you from London Heathrow Airport to Seattle for a low price.

What are the cheapest flights from London Heathrow Airport to Seattle?

The cheapest flight price from London Heathrow Airport to Seattle is £340. On average you can expect to pay £2,130. The most popular route, (London Heathrow - Seattle/Tacoma Intl), can usually be booked for £234.

What are the most reliable airlines from London Heathrow Airport to Seattle?

Consider Aeromexico (97%), KLM (92%) or Air France (92%) when booking your flight. These represent the most reliable airlines when flying from London Heathrow Airport to Seattle.

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

When booking a flight from London Heathrow Airport to Seattle, you may want to consider flying on Air Canada, Air France or Finnair as they are the most popular for this route.

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

Users have found that flying from London Heathrow Airport to Seattle on a Saturday typically leans towards higher prices. However, this doesn’t mean you still can’t find a deal. Flexibility with other aspects of your flight can still land a great price for your trip.

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

Find a great deal and save up to 38% by booking at least 44 days prior to your desired departure date, rather than waiting until the week of travel. According to our data, there are a number of flights available from London Heathrow Airport to Seattle within the next two weeks, with the cheapest ticket starting at £546.

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

Due to multiple factors, expect to potentially pay more when booking in August. For low rates, January can be a great choice for travel to Seattle. Flights to Seattle from London Heathrow Airport in January are about £556 on average during January, but can be found for as low as £322.

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

If you book a flight to Seattle from London Heathrow, you will be flying to Seattle/Tacoma Intl, which is the city’s only airport. Seattle/Tacoma Intl (SEA) is located 11.4 mi from the center of Seattle. There are 18 flights from London Heathrow to Seattle/Tacoma Intl per day from 13 different airlines.

Can I find deals for flights from Heathrow to Seattle that include hotel bookings?

Yes. In addition to deals on Heathrow to Seattle flights, Cheapflights offers holiday packages that include both flights and hotel.

How can I find direct flights from Heathrow to Seattle?

After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Heathrow to Seattle.

Can I find deals for business class flights from Heathrow to Seattle?

Yes. Cheapflights offers flight deals from Heathrow to Seattle by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

£390+ Flights from London Heathrow Airport to Seattle

Cheapflights Tip: The best prices from London Heathrow to Seattle/Tacoma Intl are usually found in February or November, booked 54 days in advance, depart on a Tuesday or Wednesday and return on a Tuesday

Cheap flight deals from Heathrow to Seattle

Round-trip from	£475
One-way from	£392
Popular in	July
Cheapest in	February
Average price	£590
Good round-trip deal	£499 or less
Good one-way deal	£526 or less

British Airways
10/9-14/9
Nonstop
19h 10m total
London to Seattle

Search Deals

Aer Lingus
1/9
1 total stop
28h 40m total
London to Seattle

Search Deals

Highest demand for flights based on searches. 15% potential increase in price (£75 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 June 2025

Search Deals

Price to beat on a round-trip flight from London Heathrow to Seattle/Tacoma Intl.

Search Deals

Price to beat on a one-way flight from London Heathrow to Seattle/Tacoma Intl.

Search Deals

Find flight deals from Heathrow to Seattle

Cheapest flights from Heathrow to Seattle
Explore the most affordable flight options available from Heathrow to Seattle. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 13 June 2025.

Wed 10/916:30LHR - SEA

Nonstop9h 50mBritish Airways

Sun 14/920:20SEA - LHR

Nonstop9h 20mBritish Airways

Deal found 11/6£475

Wed 9/709:00LHR - SEA

1 stop16h 25mAir France

Wed 16/720:25SEA - LHR

Nonstop9h 50mAir France

Deal found 11/6£476

Wed 9/706:15LHR - SEA

1 stop13h 00mVirgin Atlantic

Tue 22/717:35SEA - LHR

Nonstop9h 45mVirgin Atlantic

Deal found 12/6£478

Fri 27/621:25LHR - SEA

1 stop22h 00mIcelandair

Mon 30/623:30SEA - LHR

1 stop28h 25mIcelandair

Deal found 12/6£479

Sun 31/811:45LHR - SEA

1 stop32h 00mDelta

Mon 8/907:13SEA - LHR

1 stop15h 12mDelta

Deal found 11/6£480

Wed 9/710:30LHR - SEA

1 stop16h 41mFinnair

Wed 16/717:40SEA - LHR

1 stop13h 30mFinnair

Deal found 11/6£482

Fri 22/807:30LHR - SEA

2 stops19h 06mMultiple Airlines

Sun 14/905:30SEA - LHR

2 stops17h 00mMultiple Airlines

Deal found 12/6£487

Wed 10/908:40LHR - SEA

2 stops18h 51mAir Canada

Sun 14/905:30SEA - LHR

2 stops17h 00mAir Canada

Deal found 11/6£489

Wed 9/716:25LHR - SEA

1 stop16h 18mAmerican Airlines

Mon 21/717:40SEA - LHR

1 stop13h 30mAmerican Airlines

Deal found 12/6£492

Wed 18/609:50LHR - SEA

Nonstop9h 45mIberia

Thu 26/613:28SEA - LHR

1 stop13h 02mIberia

Deal found 11/6£495

Wed 27/806:40LHR - SEA

1 stop15h 10mScandinavian Airlines

Sat 6/916:00SEA - LHR

1 stop21h 40mScandinavian Airlines

Deal found 11/6£503

Sat 25/1014:10LHR - SEA

1 stop27h 06mLufthansa

Mon 3/1109:25SEA - LHR

2 stops17h 25mLufthansa

Deal found 11/6£526

Best flights from Heathrow to Seattle
Discover carefully curated flight deals from Heathrow to Seattle that have cost, travel time, and stopovers in mind to ensure you get the best travel experience. Data last updated 13 June 2025.

Wed 10/916:30LHR - SEA

Nonstop9h 50mBritish Airways

Sun 14/920:20SEA - LHR

Nonstop9h 20mBritish Airways

Deal found 11/6£475

Wed 9/709:00LHR - SEA

1 stop16h 25mAir France

Wed 16/720:25SEA - LHR

Nonstop9h 50mAir France

Deal found 11/6£476

Wed 9/706:15LHR - SEA

1 stop13h 00mVirgin Atlantic

Tue 22/717:35SEA - LHR

Nonstop9h 45mVirgin Atlantic

Deal found 12/6£478

Fri 27/621:25LHR - SEA

1 stop22h 00mIcelandair

Mon 30/623:30SEA - LHR

1 stop28h 25mIcelandair

Deal found 12/6£479

Sun 31/811:45LHR - SEA

1 stop32h 00mDelta

Mon 8/920:25SEA - LHR

Nonstop9h 50mDelta

Deal found 11/6£480

Wed 9/710:30LHR - SEA

1 stop16h 41mFinnair

Wed 16/717:40SEA - LHR

1 stop13h 30mFinnair

Deal found 11/6£482

Fri 22/807:30LHR - SEA

2 stops19h 06mMultiple Airlines

Sun 14/905:30SEA - LHR

2 stops17h 00mMultiple Airlines

Deal found 12/6£487

Wed 9/716:25LHR - SEA

1 stop16h 18mAmerican Airlines

Mon 14/717:40SEA - LHR

1 stop13h 30mAmerican Airlines

Deal found 12/6£489

Wed 10/908:40LHR - SEA

2 stops18h 51mAir Canada

Sun 14/905:30SEA - LHR

2 stops17h 00mAir Canada

Deal found 11/6£489

Sat 28/606:30LHR - SEA

1 stop13h 10mKLM

Tue 15/717:35SEA - LHR

Nonstop9h 45mKLM

Deal found 11/6£498

Wed 27/806:40LHR - SEA

1 stop15h 10mScandinavian Airlines

Sat 6/916:00SEA - LHR

1 stop21h 40mScandinavian Airlines

Deal found 11/6£503

Sat 25/1014:10LHR - SEA

1 stop27h 06mLufthansa

Mon 3/1109:25SEA - LHR

2 stops17h 25mLufthansa

Deal found 11/6£526

Direct flights from Heathrow to Seattle
Explore direct flight options from Heathrow to Seattle based on user searches, and compare prices and availability for your desired travel dates. Data last updated 13 June 2025.

Wed 10/916:30LHR - SEA

Nonstop9h 50mBritish Airways

Sun 14/920:20SEA - LHR

Nonstop9h 20mBritish Airways

Deal found 11/6£475

Sat 15/1112:20LHR - SEA

Nonstop10h 40mAir France

Wed 19/1117:20SEA - LHR

Nonstop9h 40mAir France

Deal found 11/6£476

Wed 2/717:25LHR - SEA

Nonstop10h 20mKLM

Wed 16/720:25SEA - LHR

Nonstop9h 50mKLM

Deal found 12/6£478

Fri 29/813:25LHR - SEA

Nonstop10h 20mVirgin Atlantic

Wed 17/917:35SEA - LHR

Nonstop9h 45mVirgin Atlantic

Deal found 12/6£478

Mon 25/817:25LHR - SEA

Nonstop10h 20mDelta

Mon 8/920:25SEA - LHR

Nonstop9h 50mDelta

Deal found 11/6£491

Sat 28/617:25LHR - SEA

Nonstop10h 20mMultiple Airlines

Tue 15/720:25SEA - LHR

Nonstop9h 50mMultiple Airlines

Deal found 10/6£573

Sun 31/809:45LHR - SEA

Nonstop9h 45mAmerican Airlines

Sun 7/913:30SEA - LHR

Nonstop9h 20mAmerican Airlines

Deal found 11/6£584

Last-minute flights from Heathrow to Seattle
Discover last-minute flight deals from Heathrow to Seattle. Data last updated 13 June 2025 and is based on user searches.

Wed 18/606:30LHR - SEA

1 stop17h 25mDelta

Wed 25/605:30SEA - LHR

1 stop20h 20mDelta

Deal found 10/6£480

Wed 18/609:50LHR - SEA

Nonstop9h 45mIberia

Thu 26/613:28SEA - LHR

1 stop13h 02mIberia

Deal found 11/6£495

Wed 18/607:30LHR - SEA

2 stops32h 31mUnited Airlines

Thu 26/605:00SEA - LHR

1 stop20h 40mUnited Airlines

Deal found 11/6£531

Fri 20/609:55LHR - SEA

1 stop14h 00mKLM

Thu 31/720:25SEA - LHR

Nonstop9h 50mKLM

Deal found 11/6£487

Sat 21/609:50LHR - SEA

Nonstop9h 45mBritish Airways

Thu 26/610:09SEA - LHR

1 stop14h 51mBritish Airways

Deal found 12/6£539

Sun 22/619:45LHR - SEA

1 stop23h 30mMultiple Airlines

Tue 8/707:45SEA - LHR

1 stop15h 00mMultiple Airlines

Deal found 11/6£506

Mon 23/621:25LHR - SEA

1 stop22h 00mIcelandair

Mon 7/715:45SEA - LHR

1 stop12h 10mIcelandair

Deal found 12/6£478

Mon 23/613:25LHR - SEA

Nonstop10h 20mVirgin Atlantic

Mon 7/713:30SEA - LHR

1 stop21h 05mVirgin Atlantic

Deal found 12/6£484

Mon 23/617:25LHR - SEA

Nonstop10h 20mAir France

Tue 22/720:25SEA - LHR

Nonstop9h 50mAir France

Deal found 11/6£484

Mon 23/615:10LHR - SEA

1 stop15h 49mAmerican Airlines

Thu 3/713:28SEA - LHR

1 stop13h 02mAmerican Airlines

Deal found 12/6£505

Mon 23/608:20LHR - SEA

1 stop18h 50mFinnair

Sun 29/617:40SEA - LHR

1 stop35h 10mFinnair

Deal found 12/6£546

Mon 23/609:30LHR - SEA

2 stops17h 06mAir Canada

Tue 22/705:30SEA - LHR

2 stops17h 00mAir Canada

Deal found 11/6£583

One-way flights from Heathrow to Seattle
Search for one-way flight options from Heathrow to Seattle. Find affordable one-way fares based on user searches. Data last updated 13 June 2025.

Mon 1/921:10LHR - SEA

1 stop28h 40mAer Lingus

Deal found 12/6£392

Wed 6/819:30LHR - SEA

3 stops55h 08mMultiple Airlines

Deal found 12/6£394

Sat 30/815:35LHR - SEA

2 stops30h 15mScandinavian Airlines

Deal found 11/6£448

Mon 18/809:50LHR - SEA

Nonstop9h 45mBritish Airways

Deal found 12/6£462

Sun 22/621:25LHR - SEA

1 stop22h 00mIcelandair

Deal found 12/6£466

Thu 19/614:10LHR - SEA

1 stop13h 07mWestJet

Deal found 11/6£471

Tue 2/909:25LHR - SEA

Nonstop9h 45mIberia

Deal found 11/6£488

Tue 17/609:25LHR - SEA

Nonstop9h 45mFinnair

Deal found 11/6£542

Cheapflights Fare Finder

Use the filters below to find and compare flights from London Heathrow Airport to Seattle that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Wed 10/9

16:30-18:20

Nonstop9h 50m

Seattle/Tacoma Intl

Sun 14/9

20:20-13:40

Nonstop9h 20m

£475

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Wed 9/7

09:00-17:25

1 stop16h 25m

Seattle/Tacoma Intl

Wed 16/7

20:25-14:15

Nonstop9h 50m

£476

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Wed 9/7

06:15-11:15

1 stop13h 00m

Seattle/Tacoma Intl

Tue 22/7

17:35-11:20

Nonstop9h 45m

£478

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Fri 27/6

21:25-11:25

1 stop22h 00m

Seattle/Tacoma Intl

Mon 30/6

23:30-11:55

1 stop28h 25m

£479

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Sun 31/8

11:45-11:45

1 stop32h 00m

Seattle/Tacoma Intl

Mon 8/9

20:25-14:15

Nonstop9h 50m

£480

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Wed 9/7

10:30-19:11

1 stop16h 41m

Seattle/Tacoma Intl

Wed 16/7

17:40-15:10

1 stop13h 30m

£482

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Fri 22/8

07:30-18:36

2 stops19h 06m

Seattle/Tacoma Intl

Sun 14/9

05:30-06:30

2 stops17h 00m

£487

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Wed 9/7

16:25-00:43

1 stop16h 18m

Seattle/Tacoma Intl

Mon 14/7

17:40-15:10

1 stop13h 30m

£489

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Wed 10/9

08:40-19:31

2 stops18h 51m

Seattle/Tacoma Intl

Sun 14/9

05:30-06:30

2 stops17h 00m

£489

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Wed 27/8

06:40-13:50

1 stop15h 10m

Seattle/Tacoma Intl

Sat 6/9

16:00-21:40

1 stop21h 40m

£503

Flights are sorted by cheapest return flights first.

Deals found on 11/6

Showing 1-10 of 23 results

Best time to book a flight from Heathrow to Seattle

Have a flexible travel schedule? Discover the best time to fly to Seattle from Heathrow 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 London Heathrow Airport to Seattle

How far ahead should I book a flight from London Heathrow Airport to Seattle?

The best time to book flights from London Heathrow Airport to Seattle is 54 days before your desired departure date. The cost of your flight will likely increase significantly if you book two weeks in advance of your flight.

What is the cheapest month to book a flight from London Heathrow Airport to Seattle?

Currently, January is the cheapest month in which you can book a flight from London Heathrow Airport to Seattle (average of £622). Flying from London Heathrow Airport to Seattle in July is currently the most expensive (average of £946). 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 LHR to SEA?

It’s typically best to fly out from London Heathrow Airport to Seattle in the evening. Doing so could potentially save you 21% on the flight price compared to flying in the morning, which is usually more expensive.

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

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

Weekly flight availability from London Heathrow Airport to Seattle

The most flights from LHR to SEA are scheduled on a Monday (22 on average). You will have fewer flight options on Sunday, which is when the least amount of flights are scheduled (11 on average).

Rainfall in Seattle by month

In terms of precipitation, rainfall in Seattle ranges from 18.0 - 168.0 inches per month. November is typically the wettest month, when rainfall can reach 168.0 mm. July is typically the driest time to visit Seattle when rainfall is around 18.0 mm.

Temperature in Seattle by month

If weather is an important factor for your trip to Seattle, 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 19.0 C. Travellers hoping to avoid the cold should look outside of December, when temperatures are typically at their lowest (around 5.0 C).

Reviews of airlines servicing Seattle

Get a feel of what it's like to fly with Delta, KLM and Finnair from London to Seattle by reading reviews from past customers. In addition to providing an overall rating, users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.

Delta

8.0

Very Good

7,950 reviews

Check prices

Reviews

1 / 20

10.0

Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!

Delta

8.0

Very Good

7,950 reviews

Delta

8.0

Very Good

7,950 reviews

Check prices

Reviews

1 / 20

10.0

Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!

KLM

7.8

Good

1,358 reviews

Delta

8.0

Very Good

7,950 reviews

Check prices

Reviews

1 / 20

10.0

Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!

Finnair

7.6

Good

1,290 reviews

Delta

8.0

Very Good

7,950 reviews

Check prices

Reviews

1 / 20

10.0

Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!

Air France

7.5

Good

1,463 reviews

Delta

8.0

Very Good

7,950 reviews

Check prices

Reviews

1 / 20

10.0

Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!

United Airlines

7.4

Good

8,790 reviews

Delta

8.0

Very Good

7,950 reviews

Check prices

Reviews

1 / 20

10.0

Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!

Related info for your journey

What airport do you fly into for flights to Seattle from London Heathrow?
If you book a flight to Seattle from London Heathrow, you will be flying to Seattle/Tacoma Intl, which is the city’s only airport. Seattle/Tacoma Intl (SEA) is located 11.4 mi from the center of Seattle. There are 18 flights from London Heathrow to Seattle/Tacoma Intl per day from 13 different airlines.
What are the cheapest airlines flying from London Heathrow Airport to Seattle round-trip?
According to our current data, British Airways (£475), Air France (£476), and Virgin Atlantic (£478) offers the cheapest pricing from London Heathrow Airport to Seattle. British Airways is priced at 17% lower than the current average price of a flight leaving 3 months from now.
What are the cheapest airlines to fly from London Heathrow Airport to Seattle one-way?
The cheapest airline one-way is Aer Lingus, with whom users have recently found tickets for as low as £392. However, be on the lookout for offers from Scandinavian Airlines and British Airways, as they are both options that can get you from London Heathrow Airport to Seattle for a low price.
What are the most reliable airlines from London Heathrow Airport to Seattle?
Consider Aeromexico (97%), KLM (92%) or Air France (92%) when booking your flight. These represent the most reliable airlines when flying from London Heathrow Airport to Seattle.
What are the cheapest flights from London Heathrow Airport to Seattle?
The cheapest flight price from London Heathrow Airport to Seattle is £340. On average you can expect to pay £2,130. The most popular route, (London Heathrow - Seattle/Tacoma Intl), can usually be booked for £234.
Can I find deals for flights from Heathrow to Seattle that include hotel bookings?
Yes. In addition to deals on Heathrow to Seattle flights, Cheapflights offers holiday packages that include both flights and hotel.
How can I find direct flights from Heathrow to Seattle?
After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Heathrow to Seattle.
Can I find deals for business class flights from Heathrow to Seattle?
Yes. Cheapflights offers flight deals from Heathrow to Seattle 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 London Heathrow Airport to Seattle?
Currently, January is the cheapest month in which you can book a flight from London Heathrow Airport to Seattle (average of £622). Flying from London Heathrow Airport to Seattle in July is currently the most expensive (average of £946). 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

Tacoma

Leavenworth

Bothell

Browse thousands of different options on Cheapflights for your next trip

Top 10 airlines flying from Heathrow to Seattle

Airline	Cheapest	Average	Flexibility	On-time
Aer Lingus	Cheapest£7	Average£645	FlexibilityNo cancel fee	On-timeN/A	Search Aer Lingus flights
Icelandair	Cheapest£352	Average£480	FlexibilityNo cancel fee	On-time76%	Search Icelandair flights
Air France	Cheapest£380	Average£553	FlexibilityNo cancel fee	On-time77%	Search Air France flights
Lufthansa	Cheapest£387	Average£484	FlexibilityNo cancel fee	On-time76%	Search Lufthansa flights
United Airlines	Cheapest£394	Average£530	FlexibilityNo cancel fee	On-time69%	Search United Airlines flights
Finnair	Cheapest£400	Average£559	FlexibilityNo cancel fee	On-time76%	Search Finnair flights
KLM	Cheapest£401	Average£567	FlexibilityNo cancel fee	On-time75%	Search KLM flights
Air Canada	Cheapest£416	Average£578	FlexibilityNo cancel fee	On-time67%	Search Air Canada flights
British Airways	Cheapest£421	Average£585	FlexibilityNo cancel fee	On-time70%	Search British Airways flights
Delta	Cheapest£439	Average£632	FlexibilityNo cancel fee	On-timeN/A	Search Delta flights

Fly with Cheapflights

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

Deals for Heathrow to Seattle 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 Heathrow to Seattle?

Cheapflights helps you find that perfect flight to Seattle from Heathrow by searching from hundreds of airlines and agencies you know and love. We are also free to use, in case you were wondering!

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

Need flexible booking options for your flight to Seattle from Heathrow? Don’t worry, Cheapflights have you covered. Use our search filter to only show flights with no change fees.

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

Yes! Start tracking prices for Heathrow to Seattle flights today and get alerted whenever prices for these flights change. To access this feature, click the bell icon next to the flight deals above, which will prompt you for a valid email address to receive your alerts.

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Millions of people come to us for their flight needs every year. We help make travel planning easy by providing useful insights and data-driven graphs that can inform your decisions.

Cheap flights from London Heathrow Airport to Seattle from £390

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 7/12. Fares are subject to change and may not be available on all flights or dates of travel.

Cheapflights Tip: The best prices from London Heathrow to Seattle/Tacoma Intl are usually found in February or November, booked 54 days in advance, depart on a Tuesday or Wednesday and return on a Tuesday

Cheap flight deals from Heathrow to Seattle

Round-trip from

One-way from

Popular in

Cheapest in

Average price

Good round-trip deal

Good one-way deal

Find flight deals from Heathrow to Seattle

Cheapest flights from Heathrow to SeattleExplore the most affordable flight options available from Heathrow to Seattle. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 13 June 2025.

Explore the most affordable flight options available from Heathrow to Seattle. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 13 June 2025.

Cheapflights Fare Finder

Use the filters below to find and compare flights from London Heathrow Airport to Seattle that are best for you.

Best time to book a flight from Heathrow to Seattle

Have a flexible travel schedule? Discover the best time to fly to Seattle from Heathrow with our price prediction graph.

Cheapflights Insights

Everything you need to know about your flight from London Heathrow Airport to Seattle

How far ahead should I book a flight from London Heathrow Airport to Seattle?

Use this chart to determine the optimal time to book a return flight from Heathrow to Seattle. Price data was last updated on 9 June 2025.

What is the cheapest month to book a flight from London Heathrow Airport to Seattle?

What is the cheapest time of day to fly from LHR to SEA?

Find hourly flight availability from Heathrow to Seattle. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated 13 June 2025.

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

Use this chart to determine the cheapest time to fly return from Heathrow to Seattle. Price data was last updated on 8 June 2025.

Weekly flight availability from London Heathrow Airport to Seattle

Explore weekly flight availability from Heathrow to Seattle. 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 13 June 2025.

Rainfall in Seattle by month

Plan your trip to Seattle by taking into account the average rainfall totals by month.

Temperature in Seattle by month

Plan your trip to Seattle by taking into account the average temperature totals by month.

Reviews of airlines servicing Seattle

Get a feel of what it's like to fly with Delta, KLM and Finnair from London to Seattle by reading reviews from past customers. In addition to providing an overall rating, 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 Heathrow to Seattle. 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 into for flights to Seattle from London Heathrow?

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

What are the cheapest airlines to fly from London Heathrow Airport to Seattle one-way?

What are the most reliable airlines from London Heathrow Airport to Seattle?

What are the cheapest flights from London Heathrow Airport to Seattle?

Can I find deals for flights from Heathrow to Seattle that include hotel bookings?

How can I find direct flights from Heathrow to Seattle?

Can I find deals for business class flights from Heathrow to Seattle?

What is the cheapest month to book a flight from London Heathrow Airport to Seattle?

Travelling to a place near London Heathrow Airport?

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Fly from Heathrow to Seattle on these airlines

Choose from the following airlines for your flight from Heathrow to Seattle. Flights are based on user searches made on Cheapflights and were last updated on 13 June 2025.

Top 10 airlines flying from Heathrow to Seattle

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Cheapest flights from Heathrow to Seattle
Explore the most affordable flight options available from Heathrow to Seattle. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 13 June 2025.