HomeSearch by dateVacation packagesHotelsFlight dealsCar rentalTravel tips & news
Heathrow

$270+ Cheap flights from Seattle (SEA) to Heathrow (LHR)

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 2/25. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — LHR
Dec 28 — Jan 41
Sat 12/28
Sat 1/4
1 adult, Economy
We work with more than 300 partners to bring you better travel deals

Find cheap flights from Seattle to Heathrow with Cheapflights

1. Tell us where you want to go
Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”
2. Select your favorite providers
We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.
3. Compare prices and book
Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.

The best prices from Seattle/Tacoma Intl to London Heathrow are usually found in November or October, booked 75 days in advance, depart on a Tuesday or Monday and return on a Wednesday

Cheap flight deals from Seattle to Heathrow

Discover tips and strategies to find the most affordable flight options for your journey from Seattle (SEA) to Heathrow (LHR). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated December 23, 2024.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$588
(Gotogate)

One-way from

$270
(Kiwi.com)

Popular in

June

Cheapest in

November

Average price

$979
Provider with most accurate pricing for Seattle/Tacoma Intl-London Heathrow flight deals.
Search Deals
Provider most trusted by Cheapflights users for Seattle/Tacoma Intl-London Heathrow flights.
Search Deals
From Seattle/Tacoma Intl to London Heathrow
Search Deals
One-way flight from Seattle/Tacoma Intl to London Heathrow
Search Deals
High demand for flights, 21% potential price rise
Search Deals
Best time to find cheap flights, 4% potential price drop
Search Deals
Average for round-trip flights in December 2024
Search Deals

Find flight deals from Seattle to Heathrow

Cheapest flights from Seattle to Heathrow
Explore the most affordable flight options available from Seattle to Heathrow. Find the lowest fares from popular airlines and budget airlines, with prices last updated on December 23, 2024.

This FlightHub deal was found by Cheapflights users on 12/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/312:35 pmSEA - LHR
1 stop20h 55mIcelandair
Mon 3/319:25 pmLHR - SEA
1 stop28h 25mIcelandair
Deal found 12/22$724
This Air Canada deal was found by Cheapflights users on 12/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/3110:35 amSEA - LHR
1 stop15h 35mMultiple Airlines
Tue 4/19:30 amLHR - SEA
2 stops19h 56mMultiple Airlines
Deal found 12/22$815
This Lufthansa deal was found by Cheapflights users on 12/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Lufthansa is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 12/2910:35 amSEA - LHR
1 stop15h 35mLufthansa
Fri 4/49:00 amLHR - SEA
1 stop15h 59mLufthansa
Deal found 12/22$821
This Iberia deal was found by Cheapflights users on 12/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Iberia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/306:50 pmSEA - LHR
Nonstop9h 25mIberia
Wed 1/223:00 pmLHR - SEA
Nonstop9h 55mIberia
Deal found 12/22$835
This Finnair deal was found by Cheapflights users on 12/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Finnair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/316:50 pmSEA - LHR
Nonstop9h 25mFinnair
Fri 4/44:30 pmLHR - SEA
Nonstop9h 50mFinnair
Deal found 12/22$836
This British Airways deal was found by Cheapflights users on 12/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure British Airways is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/311:35 pmSEA - LHR
1 stop13h 55mBritish Airways
Wed 4/29:50 amLHR - SEA
Nonstop9h 45mBritish Airways
Deal found 12/22$841
This Delta deal was found by Cheapflights users on 12/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/305:45 pmSEA - LHR
Nonstop9h 25mDelta
Wed 1/226:30 amLHR - SEA
1 stop13h 21mDelta
Deal found 12/22$852
This Air Canada deal was found by Cheapflights users on 12/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/3110:35 amSEA - LHR
1 stop15h 35mAir Canada
Sun 3/309:30 amLHR - SEA
2 stops19h 56mAir Canada
Deal found 12/22$889
This United Airlines deal was found by Cheapflights users on 12/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/2311:59 pmSEA - LHR
1 stop23h 31mUnited Airlines
Mon 2/2411:10 amLHR - SEA
1 stop34h 10mUnited Airlines
Deal found 12/22$1,093
This Aeromexico deal was found by Cheapflights users on 12/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Aeromexico is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/256:55 pmSEA - LHR
Nonstop9h 45mAir France
Tue 1/74:35 pmLHR - SEA
1 stop35h 20mAir France
Deal found 12/22$1,365
This Ovago deal was found by Cheapflights users on 12/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Ovago is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 12/278:00 pmSEA - LHR
1 stop12h 50mAer Lingus
Sun 12/298:45 pmLHR - SEA
1 stop29h 30mAer Lingus
Deal found 12/23$1,594
This WestJet deal was found by Cheapflights users on 12/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure WestJet is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/253:15 pmSEA - LHR
1 stop13h 35mWestJet
Tue 12/312:50 pmLHR - SEA
2 stops25h 15mWestJet
Deal found 12/22$1,707

Find flights from Seattle to Heathrow within your budget

Customize your flight search to find flights from Seattle to Heathrow that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated December 23, 2024.

Fly from

Any airport

Fly to

Any airport

Route

Depart

Return

Price

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Mon 2/3

2:35 pm-7:30 pm

1 stop20h 55m

London Heathrow

Mon 2/10

12:15 pm-5:00 pm

1 stop12h 45m

$584

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Tue 2/4

2:35 pm-10:50 am

1 stop12h 15m

London Heathrow

Tue 2/11

2:50 pm-2:21 pm

1 stop31h 31m

$591

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Tue 2/4

3:15 pm-12:50 pm

1 stop13h 35m

London Heathrow

Tue 2/11

2:50 pm-2:21 pm

1 stop31h 31m

$599

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Mon 4/7

1:30 pm-6:50 am

Nonstop9h 20m

London Heathrow

Wed 5/14

9:30 am-4:00 pm

1 stop14h 30m

$652

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Wed 2/5

5:45 am-7:10 am

2 stops17h 25m

London Heathrow

Wed 2/12

1:25 pm-10:07 pm

2 stops16h 42m

$657

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Mon 3/3

6:50 pm-12:15 pm

Nonstop9h 25m

London Heathrow

Tue 3/18

3:00 pm-5:55 pm

Nonstop9h 55m

$661

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Wed 4/23

10:35 am-1:20 pm

1 stop18h 45m

London Heathrow

Fri 5/2

6:30 am-2:13 pm

2 stops15h 43m

$665

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Mon 1/20

10:35 am-9:20 am

2 stops14h 45m

London Heathrow

Tue 2/4

7:40 am-1:20 pm

1 stop13h 40m

$669

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Mon 3/3

6:50 pm-12:15 pm

Nonstop9h 25m

London Heathrow

Tue 3/18

2:10 pm-11:07 pm

1 stop15h 57m

$671

SeattleLondon

SEA - LHR

SEALHR

Seattle/Tacoma Intl

Tue 1/14

11:45 am-9:40 pm

2 stops25h 55m

London Heathrow

Tue 1/21

7:30 pm-10:25 pm

2 stops34h 55m

$690

Flights are sorted by cheapest round-trip flights first.

Deals found on 12/23

Showing 1-10 of 35 results
1
2
3
4

Compare providers for flights from Seattle to Heathrow

Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Seattle to Heathrow in December.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*3 stars
AranGrantPrice Accuracy3 starsTrust Score*2 stars
eDreamsPrice Accuracy3 starsTrust Score*3 stars
CheapflightsfaresPrice Accuracy3 starsTrust Score*1 star
KAYAKPrice Accuracy1 starTrust Score*3 stars
CheapfaremartPrice Accuracy-Trust Score*3 stars
oojoPrice Accuracy3 starsTrust Score*3 stars
CheapOairPrice Accuracy2 starsTrust Score*2 stars
GotogatePrice Accuracy2 starsTrust Score*2 stars

*The Trust Score is based on feedback from users after their booking experience. It measures overall satisfaction, helping us identify issues like hidden fees, problems during the ticketing process, and the quality of customer service. This score is our best indicator of the provider's quality and reliability.

  • Most accurate provider: When it comes to deals on Seattle-London Heathrow Airport flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Seattle-London Heathrow Airport flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Seattle-London Heathrow Airport flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Seattle-London Heathrow Airport flights, Cheapflights users trust FlightHub the most. FlightHub has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for Seattle-London Heathrow Airport flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

Best time to book a flight from Seattle to Heathrow

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

Travel insights for flights from Seattle to Heathrow

Get recent, data-driven insights about flights from Seattle to Heathrow including ideal travel times, pricing trends, and more.

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

Use this chart to determine the optimal time to book a round-trip flight from Seattle to Heathrow. Price data was last updated on December 20, 2024.

Booking 75 days in advance of your planned departure date is, on average, the best time to get cheap flights from Seattle to London Heathrow Airport. The general trend is that the closer you book to the departure date, the more expensive your flight will be.

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

Currently, November is the cheapest month in which you can book a flight from Seattle to London Heathrow Airport (average of $661). Flying from Seattle to London Heathrow Airport in June is currently the most expensive (average of $1,135). 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 SEA to LHR?

Find hourly flight availability from Seattle to Heathrow. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated December 23, 2024.

When flying from Seattle to London Heathrow Airport, the time of day you fly usually plays a role in the price. Save by searching for a flight in the afternoon, which can drop the price by up to 17% versus a flight in the morning.

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

Use this chart to determine the cheapest time to fly round-trip from Seattle to Heathrow. Price data was last updated on December 16, 2024.

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

Weekly flight availability from Seattle to London Heathrow Airport

Explore weekly flight availability from Seattle to Heathrow. 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 December 23, 2024.

The most flights from SEA to LHR are scheduled on a Friday (21 on average). You will have fewer flight options on Wednesday, which is when the least amount of flights are scheduled (10 on average).

Rainfall in Heathrow by month

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

In terms of precipitation, rainfall in London Heathrow Airport ranges from 1.6 - 2.8 inches per month. January is typically the wettest month, when rainfall can reach 2.8 in. July is typically the driest time to visit London Heathrow Airport when rainfall is around 1.6 in.

Temperature in Heathrow by month

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

If weather is an important factor for your trip to London Heathrow Airport, 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 62.6 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 39.2 F).

Reviews of airlines servicing Heathrow

Get insights into the airlines that provide service to Heathrow. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Heathrow. Reviews last updated December 23, 2024.
Peruse reviews from past customers who have flown with Air Canada, British Airways and United Airlines from Seattle to London to help guide your decision. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.
Delta
8.0
Very good
8,588 reviews

Crew

8.6

Overall

8.0

Comfort

8.0

Boarding

8.2

Entertainment

7.9

Food

7.3

Reviews

1 / 10

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.

Delta
8.0
Very good
8,588 reviews
Delta
8.0
Very good
8,588 reviews

Crew

8.6

Overall

8.0

Comfort

8.0

Boarding

8.2

Entertainment

7.9

Food

7.3

Reviews

1 / 10

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.

KLM
7.8
Good
1,345 reviews
Delta
8.0
Very good
8,588 reviews

Crew

8.6

Overall

8.0

Comfort

8.0

Boarding

8.2

Entertainment

7.9

Food

7.3

Reviews

1 / 10

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.

Finnair
7.7
Good
1,285 reviews
Delta
8.0
Very good
8,588 reviews

Crew

8.6

Overall

8.0

Comfort

8.0

Boarding

8.2

Entertainment

7.9

Food

7.3

Reviews

1 / 10

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.

Virgin Atlantic
7.5
Good
666 reviews
Delta
8.0
Very good
8,588 reviews

Crew

8.6

Overall

8.0

Comfort

8.0

Boarding

8.2

Entertainment

7.9

Food

7.3

Reviews

1 / 10

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.

Air France
7.4
Good
1,503 reviews
Delta
8.0
Very good
8,588 reviews

Crew

8.6

Overall

8.0

Comfort

8.0

Boarding

8.2

Entertainment

7.9

Food

7.3

Reviews

1 / 10

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.

Related info for your journey

Find useful and relevant information for your journey from Seattle to Heathrow. 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 from for flights from Seattle to London Heathrow?

    Seattle/Tacoma Intl (SEA) is the airport you will fly out of if you book a flight from Seattle to London Heathrow. You should not have trouble finding flights to London Heathrow from Seattle/Tacoma Intl; the airport handles an average of 13 outbound flights to London Heathrow per day. You should also have plenty of airline options to choose from since 15 airlines have flights from the Seattle airport to London Heathrow. It is only a 11.4 mi journey to Seattle/Tacoma Intl (SEA) from Seattle’s city center.

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

    Our cheapest airline available from Seattle to London Heathrow Airport is Icelandair. Our recent data shows that you can find tickets from as low as $592 on this airline. Additional options worth looking into are WestJet and Iberia, starting at $599 and $616 round-trip. Icelandair is currently priced 28% below the average price you’ll pay for this route.

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

    The cheapest airlines for a one-way flight from Seattle to London Heathrow Airport are WestJet ($270), Icelandair ($272), and Lufthansa ($324).

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

    No one likes to see their flight delayed. When booking a flight from Seattle to London Heathrow Airport consider choosing KLM (89%), Singapore Airlines (86%) or Air France (84%) as they are the most reliable in getting you off to your destination on time.

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

    Looking for the cheapest flight from Seattle to London Heathrow Airport? While on average our users pay $1,827, our data indicates the cheapest price to be $407. The most popular route (Seattle/Tacoma Intl - London Heathrow), is priced around $584.

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

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

  • How can I find direct flights from Seattle to Heathrow?

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

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

    Yes. Cheapflights offers flight deals from Seattle to Heathrow 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 Seattle to London Heathrow Airport?

    Currently, November is the cheapest month in which you can book a flight from Seattle to London Heathrow Airport (average of $661). Flying from Seattle to London Heathrow Airport in June is currently the most expensive (average of $1,135). 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

Browse thousands of different options on Cheapflights for your next trip

Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.

Top 10 airlines flying from Seattle to Heathrow

Discover the top 10 airlines that operate flights from Seattle to Heathrow. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated December 23, 2024.
AirlineCheapestAverageFlexibilityOn-time
LufthansaCheapest$384Average$689FlexibilityNo cancel feeOn-time76%
IcelandairCheapest$497Average$650FlexibilityNo cancel feeOn-time76%
FinnairCheapest$560Average$832FlexibilityNo cancel feeOn-time76%
Aer LingusCheapest$581Average$828FlexibilityNo cancel feeOn-timeN/A
IberiaCheapest$583Average$748FlexibilityNo cancel feeOn-time77%
Air FranceCheapest$588Average$901FlexibilityNo cancel feeOn-time77%
KLMCheapest$597Average$848FlexibilityNo cancel feeOn-time75%
American AirlinesCheapest$600Average$890FlexibilityNo cancel feeOn-time71%
DeltaCheapest$602Average$894FlexibilityNo cancel feeOn-timeN/A
Air CanadaCheapest$610Average$893FlexibilityNo cancel feeOn-time67%
100% Free
Cheapflights is completely free to use, so you can start saving the moment you arrive.
Book with Flexibility
Our users can plan ahead with confidence and find flights with no change fees
Travel Smart
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.