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Heathrow

$342+ Cheap flights from Portland, ME (PWM) 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 7/23. Fares are subject to change and may not be available on all flights or dates of travel.
PWM — LHR
Jun 22 — Jun 291
Mon 6/22
Mon 6/29
1 adult, Economy
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Cheap flight deals from Portland to Heathrow

Cheapest flights from Portland to Heathrow
Explore the most affordable flight options available from Portland to Heathrow. Find the lowest fares from popular airlines and budget airlines, with prices last updated on May 23, 2026.

This United Airlines deal was found by Cheapflights users on 5/19. 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.
Wed 11/117:22 pm
PWM
-
LHR
1 stop10h 28m
United Airlines
Fri 11/136:50 am
LHR
-
PWM
2 stops16h 23m
United Airlines
Deal found 5/19$759
This oojo deal was found by Cheapflights users on 5/20. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/102:35 pm
PWM
-
LHR
2 stops13h 45m
Scandinavian Airlines
Tue 11/177:30 pm
LHR
-
PWM
2 stops33h 19m
Scandinavian Airlines
Deal found 5/20$831
This Delta deal was found by Cheapflights users on 5/19. 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.
Tue 11/102:35 pm
PWM
-
LHR
1 stop12h 30m
Delta
Tue 11/246:30 am
LHR
-
PWM
2 stops22h 19m
Delta
Deal found 5/19$866
This Delta deal was found by Cheapflights users on 5/20. 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.
Tue 11/101:35 pm
PWM
-
LHR
1 stop14h 25m
Delta
Tue 11/176:30 am
LHR
-
PWM
2 stops22h 19m
Delta
Deal found 5/20$867
This Delta deal was found by Cheapflights users on 5/20. 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 11/212:50 pm
PWM
-
LHR
2 stops15h 30m
Delta
Sat 11/76:30 am
LHR
-
PWM
2 stops20h 53m
Delta
Deal found 5/20$871
This Expedia deal was found by Cheapflights users on 5/20. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/26:00 am
PWM
-
LHR
2 stops20h 10m
Multiple Airlines
Sat 11/77:25 am
LHR
-
PWM
1 stop21h 18m
Multiple Airlines
Deal found 5/20$876
This Cheapflightsfares deal was found by Cheapflights users on 5/23. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/1011:17 am
PWM
-
LHR
1 stop16h 08m
Austrian Airlines
Tue 11/178:00 am
LHR
-
PWM
1 stop15h 13m
Austrian Airlines
Deal found 5/23$884

Find flight deals from Portland to Heathrow

Discover tips and strategies to find the most affordable flight options for your journey from Portland (PWM) 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 May 23, 2026.

Most accurate provider

Ovago
3 stars

Most trusted provider

Ovago
3 stars

Round-trip from

$759
(United Airlines)

One-way from

$342
(Delta)

Popular in

July

Cheapest in

October

Average price

$731
Provider with most accurate pricing for Portland-London Heathrow flight deals.
Search Deals
Provider most trusted by Cheapflights users for Portland-London Heathrow flights.
Search Deals
From Portland to London Heathrow
Search Deals
One-way flight from Portland to London Heathrow
Search Deals
Highest demand for flights based on searches. 22% potential increase in price ($240 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 6% potential price decrease ($54 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in May 2026
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Portland 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 May 23, 2026.
Use the filters below to find and compare flights from Portland to London Heathrow Airport that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

PortlandLondon

PWM - LHR

PWMLHR

Portland

Wed 11/11

2:45 pm-9:10 am

2 stops13h 25m

London Heathrow

Fri 11/13

6:50 am-4:09 pm

2 stops14h 19m

$828

PortlandLondon

PWM - LHR

PWMLHR

Portland

Tue 11/10

6:30 am-6:20 am

1 stop18h 50m

London Heathrow

Tue 11/17

6:30 am-10:23 pm

2 stops20h 53m

$866

PortlandLondon

PWM - LHR

PWMLHR

Portland

Tue 11/17

6:00 am-6:25 am

1 stop19h 25m

London Heathrow

Sat 11/21

6:30 am-10:23 pm

2 stops20h 53m

$867

PortlandLondon

PWM - LHR

PWMLHR

Portland

Tue 11/10

6:00 am-6:25 am

1 stop19h 25m

London Heathrow

Tue 11/24

8:40 am-10:23 pm

2 stops18h 43m

$867

PortlandLondon

PWM - LHR

PWMLHR

Portland

Tue 11/17

12:50 pm-9:20 am

2 stops15h 30m

London Heathrow

Sat 11/21

8:40 am-11:49 pm

2 stops20h 09m

$872
Quickest round-trip

PortlandLondon

PWM - LHR

PWMLHR

Portland

Tue 11/10

2:35 pm-8:05 am

1 stop12h 30m

London Heathrow

Tue 11/24

4:10 pm-11:49 pm

1 stop12h 39m

$895

PortlandLondon

PWM - LHR

PWMLHR

Portland

Tue 11/10

1:35 pm-9:00 am

1 stop14h 25m

London Heathrow

Tue 11/17

4:10 pm-11:49 pm

1 stop12h 39m

$896
Cheapest one-way
Quickest one-way

PortlandLondon

PWM - LHR

PWMLHR

Portland

Thu 7/23

12:40 pm-8:50 am

2 stops15h 10m

$342

PortlandLondon

PWM - LHR

PWMLHR

Portland

Thu 7/23

9:10 am-6:30 am

3 stops16h 20m

$522

Flights are sorted by cheapest round-trip flights first.

Deals found on 5/22

Sorted by cheapest first

Compare providers for flights from Portland 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 Portland to Heathrow in May.
ProviderPrice AccuracyTrust Score*
OvagoPrice Accuracy3 starsTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*3 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 Portland, Maine-London Heathrow Airport flights, users find the pricing of Ovago to be most consistent on Cheapflights vs. Ovago Users can find the same prices on Portland, Maine-London Heathrow Airport flight deals on Cheapflights vs. Ovago >95% of the time. Price accuracy is based on data collected from Portland, Maine-London Heathrow Airport flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Portland, Maine-London Heathrow Airport flights, Cheapflights users trust Ovago the most. Ovago 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 Portland, Maine-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 Portland to Heathrow

Have a flexible travel schedule? Discover the best time to fly to Heathrow from Portland 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.

Related info for your journey

Find useful and relevant information for your journey from Portland 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 Portland to London Heathrow?

    Portland (PWM) is the airport you will fly out of if you book a flight from Portland to London Heathrow. You should not have trouble finding flights to London Heathrow from Portland; the airport handles an average of 0 outbound flights to London Heathrow per day. You should also have plenty of airline options to choose from since 0 airlines have flights from the Portland airport to London Heathrow. It is only a 2.9 mi journey to Portland (PWM) from Portland’s city center.

  • How long is the flight from Portland, Maine to London Heathrow Airport?

    There are many flights that can get you from Portland, Maine to London Heathrow Airport in 13h 25m. Fly via United Airlines or Delta to get the fastest option. There are 3173 mi between Portland, Maine and London Heathrow Airport. Both multi-stop and nonstop flights can be found to your destination and back.

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

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

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

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

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

    Yes. Cheapflights offers flight deals from Portland 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.

See more FAQs

Traveling to a place near London Heathrow Airport?

Book flights to London Heathrow Airport if you plan to visit one of these locations
Ilford
Hounslow
Dorking
Winchester
Croydon
Gatwick
Southend-on-Sea
Harrow
Eastleigh
Dartford
Dover
Orpington
Watford
Northampton
Chipping Norton
Hayes
Kingston upon Thames
Eastbourne
Slough
Stansted

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