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

According to our current data, Icelandair (£456), British Airways (£456), and Lufthansa (£457) offers the cheapest pricing from London Heathrow Airport to Seattle. Icelandair is priced at 22% 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 WestJet, with whom users have recently found tickets for as low as £389. However, be on the lookout for offers from Aer Lingus and Icelandair, 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 £473. On average you can expect to pay £1,487. The most popular route, (London Heathrow - Seattle/Tacoma Intl), can usually be booked for £368.

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

Consider Singapore Airlines (94%), Aeromexico (92%) or KLM (91%) 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 40% 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 £592.

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 £579 on average during January, but can be found for as low as £330.

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.

£389+ 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 Monday

Cheap flight deals from Heathrow to Seattle

Round-trip from	£455
One-way from	£389
Popular in	July
Cheapest in	February
Average price	£548
Good round-trip deal	£547 or less
Good one-way deal	£627 or less

Air Canada
3/5-10/5
3 total stops
44h 40m total
London to Seattle

Search Deals

WestJet
12/6
3 total stops
31h 59m total
London to Seattle

Search Deals

Highest demand for flights based on searches. 15% potential increase in price (£81 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 April 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 17 April 2025.

Sat 3/506:30LHR - SEA

1 stop13h 55mMultiple Airlines

Sat 10/519:15SEA - LHR

2 stops30h 45mMultiple Airlines

Deal found 16/4£455

Sun 31/821:25LHR - SEA

1 stop22h 00mIcelandair

Thu 11/1214:35SEA - LHR

1 stop12h 15mIcelandair

Deal found 16/4£456

Wed 14/506:15LHR - SEA

1 stop18h 44mBritish Airways

Wed 21/513:30SEA - LHR

Nonstop9h 20mBritish Airways

Deal found 17/4£456

Tue 6/506:30LHR - SEA

1 stop13h 55mLufthansa

Sun 11/508:10SEA - LHR

1 stop14h 45mLufthansa

Deal found 16/4£457

Mon 1/912:15LHR - SEA

2 stops20h 13mFinnair

Sun 21/923:55SEA - LHR

2 stops22h 20mFinnair

Deal found 17/4£458

Tue 6/508:45LHR - SEA

2 stops18h 52mAir Canada

Tue 13/507:20SEA - LHR

1 stop15h 10mAir Canada

Deal found 16/4£459

Fri 16/507:25LHR - SEA

1 stop17h 34mUnited Airlines

Fri 23/514:50SEA - LHR

1 stop15h 20mUnited Airlines

Deal found 16/4£463

Tue 29/417:10LHR - SEA

2 stops37h 33mSWISS

Tue 6/514:40SEA - LHR

2 stops19h 10mSWISS

Deal found 15/4£466

Thu 5/619:30LHR - SEA

1 stop26h 20mScandinavian Airlines

Fri 13/616:00SEA - LHR

1 stop33h 20mScandinavian Airlines

Deal found 17/4£475

Mon 28/413:25LHR - SEA

Nonstop10h 20mVirgin Atlantic

Tue 13/517:35SEA - LHR

Nonstop9h 45mVirgin Atlantic

Deal found 16/4£475

Mon 28/409:55LHR - SEA

1 stop14h 05mDelta

Tue 13/511:16SEA - LHR

1 stop16h 09mDelta

Deal found 16/4£491

Wed 30/417:25LHR - SEA

Nonstop10h 20mAir France

Wed 7/520:20SEA - LHR

Nonstop9h 55mAir France

Deal found 17/4£496

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 17 April 2025.

Sat 3/506:30LHR - SEA

1 stop13h 55mMultiple Airlines

Sat 10/519:15SEA - LHR

2 stops30h 45mMultiple Airlines

Deal found 16/4£455

Sun 31/821:25LHR - SEA

1 stop22h 00mIcelandair

Thu 11/1214:35SEA - LHR

1 stop12h 15mIcelandair

Deal found 16/4£456

Wed 14/506:15LHR - SEA

1 stop18h 44mBritish Airways

Wed 21/513:30SEA - LHR

Nonstop9h 20mBritish Airways

Deal found 17/4£456

Tue 6/506:30LHR - SEA

1 stop13h 55mLufthansa

Sun 11/508:10SEA - LHR

1 stop14h 45mLufthansa

Deal found 16/4£457

Mon 1/912:15LHR - SEA

2 stops20h 13mFinnair

Sun 21/923:55SEA - LHR

2 stops22h 20mFinnair

Deal found 17/4£458

Fri 16/507:25LHR - SEA

1 stop17h 34mUnited Airlines

Fri 23/514:50SEA - LHR

1 stop15h 20mUnited Airlines

Deal found 16/4£463

Tue 29/417:10LHR - SEA

2 stops37h 33mSWISS

Tue 6/514:40SEA - LHR

2 stops19h 10mSWISS

Deal found 15/4£466

Mon 28/409:30LHR - SEA

2 stops20h 11mAir Canada

Tue 13/507:20SEA - LHR

1 stop18h 40mAir Canada

Deal found 16/4£468

Mon 5/506:30LHR - SEA

1 stop17h 27mKLM

Tue 20/520:20SEA - LHR

Nonstop9h 55mKLM

Deal found 16/4£469

Mon 28/411:45LHR - SEA

1 stop32h 00mVirgin Atlantic

Tue 13/520:20SEA - LHR

Nonstop9h 55mVirgin Atlantic

Deal found 16/4£470

Thu 5/619:30LHR - SEA

1 stop26h 20mScandinavian Airlines

Fri 13/616:00SEA - LHR

1 stop33h 20mScandinavian Airlines

Deal found 17/4£475

Mon 28/409:55LHR - SEA

1 stop14h 05mDelta

Tue 13/511:16SEA - LHR

1 stop16h 09mDelta

Deal found 16/4£491

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 17 April 2025.

Wed 14/517:25LHR - SEA

Nonstop10h 15mVirgin Atlantic

Thu 22/520:20SEA - LHR

Nonstop9h 55mVirgin Atlantic

Deal found 16/4£467

Tue 6/517:25LHR - SEA

Nonstop10h 20mAir France

Mon 12/520:20SEA - LHR

Nonstop9h 55mAir France

Deal found 16/4£474

Wed 30/416:30LHR - SEA

Nonstop9h 50mBritish Airways

Wed 7/520:20SEA - LHR

Nonstop9h 20mBritish Airways

Deal found 17/4£482

Mon 28/413:25LHR - SEA

Nonstop10h 20mMultiple Airlines

Tue 13/520:20SEA - LHR

Nonstop9h 55mMultiple Airlines

Deal found 17/4£490

Mon 28/417:25LHR - SEA

Nonstop10h 20mDelta

Tue 13/517:35SEA - LHR

Nonstop9h 45mDelta

Deal found 17/4£503

Thu 28/817:25LHR - SEA

Nonstop10h 20mKLM

Wed 10/920:25SEA - LHR

Nonstop9h 50mKLM

Deal found 16/4£541

Tue 10/609:25LHR - SEA

Nonstop9h 45mIberia

Mon 23/613:30SEA - LHR

Nonstop9h 20mIberia

Deal found 17/4£555

Tue 26/809:25LHR - SEA

Nonstop9h 45mAmerican Airlines

Fri 5/913:30SEA - LHR

Nonstop9h 20mAmerican Airlines

Deal found 16/4£570

Mon 5/509:50LHR - SEA

Nonstop9h 45mFinnair

Tue 28/1019:50SEA - LHR

Nonstop9h 25mFinnair

Deal found 17/4£639

Last-minute flights from Heathrow to Seattle
Discover last-minute flight deals from Heathrow to Seattle. Data last updated 17 April 2025 and is based on user searches.

Tue 22/421:25LHR - SEA

1 stop31h 15mIcelandair

Tue 29/419:00SEA - LHR

1 stop17h 20mIcelandair

Deal found 16/4£458

Tue 22/413:25LHR - SEA

2 stops17h 44mAer Lingus

Fri 2/518:45SEA - LHR

1 stop12h 10mAer Lingus

Deal found 17/4£652

Wed 23/406:50LHR - SEA

2 stops20h 11mUnited Airlines

Sun 27/406:15SEA - LHR

2 stops19h 05mUnited Airlines

Deal found 16/4£476

Wed 23/406:30LHR - SEA

1 stop13h 15mKLM

Thu 8/520:20SEA - LHR

Nonstop9h 55mKLM

Deal found 17/4£625

Thu 24/414:10LHR - SEA

1 stop12h 18mLufthansa

Wed 30/407:00SEA - LHR

1 stop15h 20mLufthansa

Deal found 16/4£469

Thu 24/414:10LHR - SEA

1 stop27h 43mAir Canada

Sat 10/507:20SEA - LHR

1 stop15h 10mAir Canada

Deal found 15/4£473

Thu 24/417:20LHR - SEA

2 stops27h 23mFinnair

Wed 30/413:35SEA - LHR

1 stop14h 40mFinnair

Deal found 16/4£489

Thu 24/408:20LHR - SEA

1 stop16h 39mBritish Airways

Wed 30/420:20SEA - LHR

Nonstop9h 20mBritish Airways

Deal found 16/4£492

Thu 24/408:30LHR - SEA

2 stops18h 31mMultiple Airlines

Sat 10/505:30SEA - LHR

2 stops17h 00mMultiple Airlines

Deal found 16/4£498

Thu 24/417:25LHR - SEA

Nonstop10h 20mAir France

Wed 30/420:20SEA - LHR

Nonstop9h 55mAir France

Deal found 16/4£506

Fri 25/413:25LHR - SEA

Nonstop10h 20mDelta

Sun 27/423:30SEA - LHR

1 stop23h 15mDelta

Deal found 17/4£536

Sat 26/417:25LHR - SEA

Nonstop10h 20mVirgin Atlantic

Thu 1/520:20SEA - LHR

Nonstop9h 55mVirgin Atlantic

Deal found 17/4£500

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 17 April 2025.

Thu 12/614:10LHR - SEA

3 stops31h 59mWestJet

Deal found 16/4£389

Tue 22/409:50LHR - SEA

1 stop15h 09mAer Lingus

Deal found 16/4£401

Mon 14/706:15LHR - SEA

3 stops22h 13mMultiple Airlines

Deal found 16/4£407

Thu 21/813:05LHR - SEA

1 stop12h 45mIcelandair

Deal found 16/4£472

Wed 14/513:25LHR - SEA

Nonstop10h 20mAir France

Deal found 16/4£479

Mon 28/416:30LHR - SEA

Nonstop9h 50mIberia

Deal found 16/4£498

Tue 13/509:25LHR - SEA

Nonstop9h 45mFinnair

Deal found 16/4£513

Tue 23/917:25LHR - SEA

Nonstop10h 25mScandinavian Airlines

Deal found 16/4£521

Tue 24/616:30LHR - SEA

Nonstop9h 50mBritish Airways

Deal found 15/4£528

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

Sat 3/5

06:30-12:25

1 stop13h 55m

Seattle/Tacoma Intl

Sat 10/5

19:15-10:00

2 stops30h 45m

£455

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Sun 31/8

21:25-11:25

1 stop22h 00m

Seattle/Tacoma Intl

Thu 11/12

14:35-10:50

1 stop12h 15m

£456

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Wed 14/5

06:15-16:59

1 stop18h 44m

Seattle/Tacoma Intl

Wed 21/5

13:30-06:50

Nonstop9h 20m

£456

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Tue 6/5

06:30-12:25

1 stop13h 55m

Seattle/Tacoma Intl

Sun 11/5

08:10-06:55

1 stop14h 45m

£457

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Mon 1/9

12:15-00:28

2 stops20h 13m

Seattle/Tacoma Intl

Sun 21/9

23:55-06:15

2 stops22h 20m

£458

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Tue 6/5

08:45-19:37

2 stops18h 52m

Seattle/Tacoma Intl

Tue 13/5

07:20-06:30

1 stop15h 10m

£459

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Fri 16/5

07:25-16:59

1 stop17h 34m

Seattle/Tacoma Intl

Fri 23/5

14:50-14:10

1 stop15h 20m

£463

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Tue 29/4

17:10-22:43

2 stops37h 33m

Seattle/Tacoma Intl

Tue 6/5

14:40-17:50

2 stops19h 10m

£466

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Mon 5/5

06:30-15:57

1 stop17h 27m

Seattle/Tacoma Intl

Tue 20/5

20:20-14:15

Nonstop9h 55m

£469

LondonSeattle

LHR - SEA

LHRSEA

London Heathrow

Thu 5/6

19:30-13:50

1 stop26h 20m

Seattle/Tacoma Intl

Fri 13/6

16:00-09:20

1 stop33h 20m

£475

Flights are sorted by cheapest return flights first.

Deals found on 16/4

Showing 1-10 of 25 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 23% 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 Tuesday, 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

7,917 reviews

Check prices

Reviews

1 / 20

10.0

Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception

Delta

8.0

Very Good

7,917 reviews

Delta

8.0

Very Good

7,917 reviews

Check prices

Reviews

1 / 20

10.0

Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception

KLM

7.8

Good

1,329 reviews

Delta

8.0

Very Good

7,917 reviews

Check prices

Reviews

1 / 20

10.0

Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception

Finnair

7.6

Good

1,269 reviews

Delta

8.0

Very Good

7,917 reviews

Check prices

Reviews

1 / 20

10.0

Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception

Air France

7.5

Good

1,435 reviews

Delta

8.0

Very Good

7,917 reviews

Check prices

Reviews

1 / 20

10.0

Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception

SWISS

7.5

Good

1,580 reviews

Delta

8.0

Very Good

7,917 reviews

Check prices

Reviews

1 / 20

10.0

Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception

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, Icelandair (£456), British Airways (£456), and Lufthansa (£457) offers the cheapest pricing from London Heathrow Airport to Seattle. Icelandair is priced at 22% 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 WestJet, with whom users have recently found tickets for as low as £389. However, be on the lookout for offers from Aer Lingus and Icelandair, 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 Singapore Airlines (94%), Aeromexico (92%) or KLM (91%) 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 £473. On average you can expect to pay £1,487. The most popular route, (London Heathrow - Seattle/Tacoma Intl), can usually be booked for £368.
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£8	Average£684	FlexibilityNo cancel fee	On-timeN/A	Search Aer Lingus flights
Icelandair	Cheapest£373	Average£501	FlexibilityNo cancel fee	On-time76%	Search Icelandair flights
Air France	Cheapest£390	Average£574	FlexibilityNo cancel fee	On-time77%	Search Air France flights
Lufthansa	Cheapest£400	Average£501	FlexibilityNo cancel fee	On-time76%	Search Lufthansa flights
United Airlines	Cheapest£404	Average£628	FlexibilityNo cancel fee	On-time69%	Search United Airlines flights
KLM	Cheapest£412	Average£590	FlexibilityNo cancel fee	On-time75%	Search KLM flights
Finnair	Cheapest£418	Average£577	FlexibilityNo cancel fee	On-time76%	Search Finnair flights
British Airways	Cheapest£438	Average£628	FlexibilityNo cancel fee	On-time70%	Search British Airways flights
Delta	Cheapest£450	Average£623	FlexibilityNo cancel fee	On-timeN/A	Search Delta flights
Virgin Atlantic	Cheapest£456	Average£606	FlexibilityNo cancel fee	On-time72%	Search Virgin Atlantic 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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Cheap flights from London Heathrow Airport to Seattle from £389

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 12/6. 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 Monday

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 17 April 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 17 April 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 11 April 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 17 April 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 30 March 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 17 April 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 17 April 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 17 April 2025.