How does KAYAK find such low prices on flights from Washington to London Heathrow Airport?

KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Washington to London Heathrow Airport. Visit our flight page for the latest deals!>/a>

How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Washington to London Heathrow Airport?

KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to London Heathrow Airport from Washington is likely to change within 7 days, so travelers know whether to wait or book now. Visit our flight page for the latest deals!>/a>

What is the Hacker Fare option on flights from Washington to London Heathrow Airport?

Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to London Heathrow Airport with an airline and back to Washington with another airline. Visit our flight page for the latest deals!>/a>

What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Washington to London Heathrow Airport?

Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to London Heathrow Airport from Washington up to 3 days before/after your preferred dates. You can then pick the flights that suit you best. Visit our flight page for the latest deals!>/a>

$316 CHEAP FLIGHTS from Washington to London Heathrow (LHR)

LHR

KAYAK searches hundreds of travel sites at once for deals on flights to London Heathrow Airport

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Cheapest round-trip

$543

Overall average: $728

Icelandair

Tue 4/14Wed 4/29

SEA - LHR • 1 stop

Cheapest non-stop

$627

Typical prices: $617-$820

Virgin Atlantic

Mon 3/9Tue 3/24

SEA - LHR • Non-stop

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We hope you love your trip to Heathrow!

Flight Deals

Cheap Flights from Washington to Heathrow

Discover the best prices for you by selecting your travel dates on KAYAK.

Round-trip

One-way

Last minute

Direct

Recent round-trip flight deals from Washington to Heathrow

Tue, Apr 14 - Wed, Apr 29

7:00 pm - 8:20 pm

SEA

LHR

17h 20m

1 stop

9:25 pm - 5:55 pm

LHR

SEA

28h 30m

1 stop

$543Icelandair

Mon, Apr 13 - Mon, Apr 20

3:40 pm - 8:20 pm

SEA

LHR

20h 40m

1 stop

1:05 pm - 8:40 pm

LHR

SEA

15h 35m

1 stop

$544Icelandair

Tue, Apr 14 - Fri, Apr 24

3:40 pm - 8:20 pm

SEA

LHR

20h 40m

1 stop

9:25 pm - 5:55 pm

LHR

SEA

28h 30m

1 stop

$545Icelandair

Tue, Mar 10 - Tue, Mar 17

12:45 pm - 9:40 am

PSC

LHR

13h 55m

1 stop

6:35 am - 8:54 pm

LHR

PSC

21h 19m

2 stops

$632United Airlines

Tue, Mar 10 - Tue, Mar 17

5:05 am - 10:50 am

PSC

LHR

22h 45m

3 stops

6:35 am - 8:54 pm

LHR

PSC

21h 19m

2 stops

$636United Airlines

Tue, May 5 - Fri, May 15

12:28 pm - 12:10 pm

PSC

LHR

15h 42m

1 stop

6:30 am - 7:35 pm

LHR

PSC

21h 05m

2 stops

$648Delta

Sun, Apr 26 - Fri, May 15

7:38 pm - 3:35 pm

GEG

LHR

11h 57m

1 stop

8:40 am - 9:13 pm

LHR

GEG

20h 33m

2 stops

$648Delta

Sun, Mar 8 - Sun, Mar 15

6:00 am - 11:20 am

GEG

LHR

22h 20m

2 stops

1:25 pm - 9:59 pm

LHR

GEG

39h 34m

2 stops

$649Air Canada

Wed, Apr 22 - Fri, May 8

7:10 am - 8:35 am

GEG

LHR

17h 25m

2 stops

2:05 pm - 6:36 pm

LHR

GEG

36h 31m

2 stops

$657Air Canada

Thu, Mar 19 - Tue, Mar 24

6:30 am - 7:05 am

PSC

LHR

17h 35m

1 stop

10:45 am - 4:55 pm

LHR

PSC

13h 10m

1 stop

$660Scandinavian Airlines

Useful Info

Low season	January
High season	July
Cheapest flight	$316

Best time to beat the crowds with an average 12% drop in price.

Most popular time to fly with an average 17% increase in price.

Flight from Portland to London Heathrow Airport

Verified travelerFlew with British Airways

SEA

LHR

Apr 2025

Make sure you have plenty of time between flights if you are delayed.

Verified travelerFlew with British Airways

SEA

LHR

Feb 2025

Don’t take a flight if you sick, or if you have no choice prepare to stay covered with mask throughout the flight

Verified travelerFlew with British Airways

SEA

LHR

Apr 2024

Bring a sack lunch -- airport food was very expensive.

How does KAYAK find such low prices on flights from Washington to London Heathrow Airport?
KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Washington to London Heathrow Airport.
How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Washington to London Heathrow Airport?
KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to London Heathrow Airport from Washington is likely to change within 7 days, so travelers know whether to wait or book now.
What is the Hacker Fare option on flights from Washington to London Heathrow Airport?
Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to London Heathrow Airport with an airline and back to Washington with another airline.
What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Washington to London Heathrow Airport?
Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to London Heathrow Airport from Washington up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

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Ilford

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Guildford

Eastbourne

Kingston upon Thames

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Ipswich

Bedford

Twickenham

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London Heathrow Airport (LHR)

LHR

$316 Find Cheap Flights from Washington to London Heathrow Airport

KAYAK searches hundreds of travel sites at once for deals on flights to London Heathrow Airport

Everything you should know

Cheap Flights from Washington to Heathrow

Recent round-trip flight deals from Washington to Heathrow

Recent one-way flight deals from Washington to Heathrow

Recent last minute flight deals from Washington to Heathrow

Recent direct flight deals from Washington to Heathrow

Good to know

Flights from Washington to Heathrow: the best tips from KAYAK users

FAQs for booking Washington to London Heathrow Airport flights

How does KAYAK find such low prices on flights from Washington to London Heathrow Airport?

KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Washington to London Heathrow Airport.

How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Washington to London Heathrow Airport?

KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to London Heathrow Airport from Washington is likely to change within 7 days, so travelers know whether to wait or book now.

What is the Hacker Fare option on flights from Washington to London Heathrow Airport?

Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to London Heathrow Airport with an airline and back to Washington with another airline.

What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Washington to London Heathrow Airport?

Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to London Heathrow Airport from Washington up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

Traveling to a place near Heathrow?

Everything you need to know for your flight to Heathrow

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Complete your trip to Heathrow with a hotel stay or car rental

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Flights from domestic origins to Washington

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