$320+ Cheap flights from Portland, ME (PWM) to Heathrow (LHR)
This is the cheapest round-trip flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 11/16. Fares are subject to change and may not be available on all flights or dates of travel.
PWM — LHR
Oct 22 — Oct 291
Round-trip
1 adult, Economy
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Find cheap flights from Portland 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.Cheap flight deals from Portland to Heathrow
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Best
Last-minute
One-way
Cheapest flights from Portland to HeathrowExplore 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 September 22, 2026.
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 September 22, 2026.
This United Airlines deal was found by Cheapflights users on 9/17. 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 11/163:41 pm -
2 stops14h 34m
Wed 11/189:00 am -
2 stops43h 21m
Deal found 9/17![United Airlines logo]()
$735
This Delta deal was found by Cheapflights users on 9/21. 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 11/102:05 pm -
1 stop12h 45m
Tue 11/176:30 am -
2 stops22h 49m
Deal found 9/21![Delta logo]()
$736
This Delta deal was found by Cheapflights users on 9/20. 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.
Wed 11/411:20 am -
1 stop14h 00m
Wed 11/1111:30 am -
2 stops17h 49m
Deal found 9/20![Delta logo]()
$737
This United Airlines deal was found by Cheapflights users on 9/21. 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 11/95:08 pm -
1 stop33h 47m
Thu 11/126:50 am -
2 stops17h 12m
Deal found 9/21![United Airlines logo]()
$742
This Delta deal was found by Cheapflights users on 9/17. 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 11/36:01 am -
2 stops20h 44m
Thu 11/128:40 am -
2 stops20h 39m
Deal found 9/17![Delta logo]()
$743
This Air France deal was found by Cheapflights users on 9/19. 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 Air France is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/102:05 pm -
1 stop13h 55m
Tue 11/173:50 pm -
1 stop13h 29m
Deal found 9/19![Multiple Airlines logo]()
$744
This KLM deal was found by Cheapflights users on 9/17. 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 KLM is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/102:05 pm -
1 stop16h 35m
Tue 11/1711:35 am -
1 stop17h 44m
Deal found 9/17![KLM logo]()
$745
This Virgin Atlantic deal was found by Cheapflights users on 9/17. 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 Virgin Atlantic is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/246:00 am -
1 stop19h 25m
Tue 12/16:20 am -
2 stops22h 14m
Deal found 9/17![Virgin Atlantic logo]()
$774
Best flights from Portland to HeathrowDiscover carefully curated flight deals from Portland to Heathrow that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated September 22, 2026.
Discover carefully curated flight deals from Portland to Heathrow that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated September 22, 2026.
This Delta deal was found by Cheapflights users on 9/20. 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 11/102:05 pm -
1 stop12h 45m
Tue 11/176:30 am -
2 stops22h 49m
Deal found 9/20![Delta logo]()
$736
This KLM deal was found by Cheapflights users on 9/19. 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 KLM is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/36:01 am -
1 stop20h 49m
Tue 11/1011:45 am -
2 stops17h 34m
Deal found 9/19![KLM logo]()
$737
This Delta deal was found by Cheapflights users on 9/19. 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 11/106:00 am -
1 stop19h 25m
Tue 11/246:30 am -
2 stops22h 01m
Deal found 9/19![Delta logo]()
$736
This KLM deal was found by Cheapflights users on 9/17. 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 KLM is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/154:15 pm -
1 stop11h 35m
Thu 10/2211:45 am -
2 stops17h 25m
Deal found 9/17![KLM logo]()
$777
This Delta deal was found by Cheapflights users on 9/19. 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.
Wed 10/74:47 pm -
2 stops14h 18m
Wed 10/1411:45 am -
2 stops17h 25m
Deal found 9/19![Delta logo]()
$741
This KLM deal was found by Cheapflights users on 9/20. 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 KLM is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 11/611:55 am -
1 stop14h 10m
Tue 11/1011:45 am -
2 stops17h 34m
Deal found 9/20![KLM logo]()
$787
This Delta deal was found by Cheapflights users on 9/22. 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.
Fri 10/96:04 am -
1 stop20h 11m
Wed 10/1411:30 am -
2 stops17h 40m
Deal found 9/22![Delta logo]()
$787
Last-minute flights from Portland to HeathrowDiscover last-minute flight deals from Portland to Heathrow. Data last updated September 22, 2026 and is based on user searches.
Discover last-minute flight deals from Portland to Heathrow. Data last updated September 22, 2026 and is based on user searches.
This Delta deal was found by Cheapflights users on 9/19. 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.
Wed 10/76:04 am -
1 stop19h 16m
Wed 10/148:40 am -
2 stops20h 30m
Deal found 9/19![Delta logo]()
$737
This Delta deal was found by Cheapflights users on 9/21. 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.
Fri 10/96:04 am -
1 stop19h 16m
Wed 10/1411:30 am -
2 stops17h 40m
Deal found 9/21![Delta logo]()
$787
This Delta deal was found by Cheapflights users on 9/19. 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.
Wed 10/144:15 pm -
1 stop14h 50m
Wed 10/218:40 am -
2 stops19h 55m
Deal found 9/19![Delta logo]()
$736
This KLM deal was found by Cheapflights users on 9/17. 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 KLM is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/154:15 pm -
1 stop11h 35m
Thu 10/2211:45 am -
2 stops17h 25m
Deal found 9/17![KLM logo]()
$777
This Air France deal was found by Cheapflights users on 9/17. 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 France is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/152:09 pm -
1 stop18h 06m
Thu 10/224:20 pm -
1 stop12h 50m
Deal found 9/17![Multiple Airlines logo]()
$784
One-way flights from Portland to HeathrowSearch for one-way flight options from Portland to Heathrow. Find affordable one-way fares based on user searches. Data last updated September 22, 2026.
Search for one-way flight options from Portland to Heathrow. Find affordable one-way fares based on user searches. Data last updated September 22, 2026.
This Cheapflightsfares deal was found by Cheapflights users on 9/21. 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.
Mon 11/166:30 am -
1 stop10h 10m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/21![JetBlue logo]()
$320
This Expedia deal was found by Cheapflights users on 9/20. 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.
Fri 10/96:00 am -
2 stops43h 30m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/20![Air Canada logo]()
$324
This United Airlines deal was found by Cheapflights users on 9/21. 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.
Sun 11/155:30 am -
2 stops19h 25m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/21![United Airlines logo]()
$329
This Delta deal was found by Cheapflights users on 9/20. 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.
Fri 10/96:04 am -
1 stop19h 16m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/20![Delta logo]()
$333
This United Airlines deal was found by Cheapflights users on 9/18. 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.
Thu 10/85:15 am -
2 stops24h 00m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/18![United Airlines logo]()
$341
This Justfly.com deal was found by Cheapflights users on 9/21. 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 Justfly.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 11/155:50 am -
2 stops44h 20m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/21![Air Canada logo]()
$344
This Cheapflightsfares deal was found by Cheapflights users on 9/18. 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.
Thu 10/86:00 am -
1 stop9h 45m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/18![JetBlue logo]()
$390
This Air Canada deal was found by Cheapflights users on 9/21. 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.
Mon 11/168:49 am -
3 stops16h 41m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/21![Air Canada logo]()
$448
This Kiwi.com deal was found by Cheapflights users on 9/18. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/812:35 pm -
3 stops50h 30m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/18![Multiple Airlines logo]()
$690
This Air Canada deal was found by Cheapflights users on 9/21. 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.
Thu 10/88:03 am -
3 stops17h 27m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/21![Air Canada logo]()
$692
This Kiwi.com deal was found by Cheapflights users on 9/20. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/93:53 pm -
3 stops43h 47m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/20![Multiple Airlines logo]()
$984
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 September 22, 2026.
Most accurate provider | Ovago 3 stars |
|---|---|
Most trusted provider | Ovago 3 stars |
Round-trip from | $735 (United Airlines) |
One-way from | $320 (Cheapflightsfares) |
Popular in | June |
Cheapest in | February |
Average price | $1,171 |
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 7,457,451 searches. Data last updated September 22, 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
Cheapest round-trip
PortlandLondon
PWM Portland - LHR London Heathrow
PWMLHR
Portland
Fri 10/9
6:00 am-6:30 am
2 stops43h 30m
London Heathrow
Wed 12/31
12:00 am-6:00 pm
Nonstop0h 00m
$324
PortlandLondon
PWM Portland - LHR London Heathrow
PWMLHR
Portland
Sun 11/15
5:30 am-5:55 am
2 stops19h 25m
London Heathrow
Wed 12/31
12:00 am-6:00 pm
Nonstop0h 00m
$329
PortlandLondon
PWM Portland - LHR London Heathrow
PWMLHR
Portland
Mon 11/16
5:35 am-9:00 pm
2 stops34h 25m
London Heathrow
Wed 12/31
12:00 am-6:00 pm
Nonstop0h 00m
$329
PortlandLondon
PWM Portland - LHR London Heathrow
PWMLHR
Portland
Fri 10/9
6:04 am-6:20 am
1 stop19h 16m
London Heathrow
Wed 12/31
12:00 am-6:00 pm
Nonstop0h 00m
$333
PortlandLondon
PWM Portland - LHR London Heathrow
PWMLHR
Portland
Thu 10/8
5:15 am-10:15 am
2 stops24h 00m
London Heathrow
Wed 12/31
12:00 am-6:00 pm
Nonstop0h 00m
$341
Quickest round-trip
PortlandLondon
PWM Portland - LHR London Heathrow
PWMLHR
Portland
Thu 10/8
6:00 am-8:45 pm
1 stop9h 45m
London Heathrow
Wed 12/31
12:00 am-6:00 pm
Nonstop0h 00m
$390
PortlandLondon
PWM Portland - LHR London Heathrow
PWMLHR
Portland
Thu 10/8
12:35 pm-8:05 pm
3 stops50h 30m
London Heathrow
Wed 12/31
12:00 am-6:00 pm
Nonstop0h 00m
$690
PortlandLondon
PWM Portland - LHR London Heathrow
PWMLHR
Portland
Tue 11/10
2:05 pm-7:50 am
1 stop12h 45m
London Heathrow
Tue 11/17
6:30 am-12:19 am
2 stops22h 49m
$736
PortlandLondon
PWM Portland - LHR London Heathrow
PWMLHR
Portland
Tue 11/10
6:00 am-6:25 am
1 stop19h 25m
London Heathrow
Tue 11/24
6:30 am-11:31 pm
2 stops22h 01m
$736
PortlandLondon
PWM Portland - LHR London Heathrow
PWMLHR
Portland
Tue 11/3
6:01 am-7:50 am
1 stop20h 49m
London Heathrow
Tue 11/10
11:45 am-12:19 am
2 stops17h 34m
$737
Showing 1-10 of 16 resultsSorted 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 September.
| Provider | Price Accuracy | Trust Score* |
|---|---|---|
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars |
- 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.
PWM-LHR
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.
Traveling to a place near London Heathrow Airport?
Book flights to London Heathrow Airport if you plan to visit one of these locationsIlford
Dorking
Gatwick
Hounslow
Harrow
Wembley
Southend-on-Sea
Basingstoke
Watford
Northampton
Dartford
Winchester
Croydon
Chipping Norton
Kingston upon Thames
Eastbourne
Slough
Stansted
Sutton
Luton
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