$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 10/10. Fares are subject to change and may not be available on all flights or dates of travel.
PWM — LHR
Oct 31 — Nov 71
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
Cheapest
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 October 1, 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 October 1, 2026.
This United Airlines deal was found by Cheapflights users on 9/28. 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 11/165:35 am -
2 stops23h 30m
Wed 11/189:00 am -
2 stops43h 21m
Deal found 9/28![United Airlines logo]()
$734
This United Airlines deal was found by Cheapflights users on 9/30. 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 11/98:49 am -
2 stops41h 21m
Thu 11/126:50 am -
2 stops21h 31m
Deal found 9/30![United Airlines logo]()
$739
This United Airlines deal was found by Cheapflights users on 9/28. 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 11/15:08 pm -
1 stop33h 47m
Wed 11/46:50 am -
2 stops21h 31m
Deal found 9/28![United Airlines logo]()
$741
This United Airlines deal was found by Cheapflights users on 9/26. 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 11/233:41 pm -
2 stops34h 29m
Thu 11/266:50 am -
2 stops17h 12m
Deal found 9/26![United Airlines logo]()
$747
This Expedia deal was found by Cheapflights users on 9/28. 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 10/266:30 am -
1 stop11h 10m
Mon 11/28:05 am -
1 stop20h 38m
Deal found 9/28![JetBlue logo]()
$848
This Travelocity deal was found by Cheapflights users on 9/28. 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 Travelocity is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/216:00 am -
2 stops19h 30m
Sat 11/712:20 pm -
1 stop16h 23m
Deal found 9/28![Multiple Airlines logo]()
$855
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 October 1, 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 October 1, 2026.
This United Airlines deal was found by Cheapflights users on 9/28. 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 11/165:35 am -
2 stops23h 30m
Wed 11/189:00 am -
2 stops43h 21m
Deal found 9/28![United Airlines logo]()
$734
This Delta deal was found by Cheapflights users on 9/28. 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 11/1112:45 pm -
2 stops15h 40m
Sun 11/158:40 am -
2 stops20h 39m
Deal found 9/28![Delta logo]()
$868
This United deal was found by Cheapflights users on 9/30. 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 is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 10/186:00 am -
1 stop9h 40m
Sat 10/319:00 am -
2 stops53h 00m
Deal found 9/30![Multiple Airlines logo]()
$890
This United Airlines deal was found by Cheapflights users on 9/26. 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.
Tue 11/102:05 pm -
1 stop15h 45m
Tue 11/1712:05 pm -
2 stops16h 16m
Deal found 9/26![United Airlines logo]()
$861
This Delta deal was found by Cheapflights users on 9/28. 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.
Thu 11/124:03 pm -
2 stops13h 27m
Thu 11/1910:00 am -
2 stops19h 19m
Deal found 9/28![Delta logo]()
$868
This United Airlines deal was found by Cheapflights users on 9/27. 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.
Tue 10/2710:50 am -
2 stops15h 50m
Tue 11/1012:05 pm -
2 stops16h 16m
Deal found 9/27![United Airlines logo]()
$865
This Delta deal was found by Cheapflights users on 9/26. 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.
Sat 1/162:35 pm -
1 stop13h 50m
Sat 3/1311:15 am -
2 stops17h 34m
Deal found 9/26![Delta logo]()
$875
This United Airlines deal was found by Cheapflights users on 9/30. 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 11/162:05 pm -
2 stops14h 05m
Mon 11/2312:05 pm -
2 stops16h 16m
Deal found 9/30![United Airlines logo]()
$866
This Delta deal was found by Cheapflights users on 9/28. 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.
Sat 2/1312:50 pm -
2 stops15h 35m
Sun 2/218:40 am -
2 stops20h 09m
Deal found 9/28![Delta logo]()
$880
This United Airlines deal was found by Cheapflights users on 9/26. 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 10/263:41 pm -
2 stops15h 09m
Mon 11/212:05 pm -
2 stops16h 16m
Deal found 9/26![United Airlines logo]()
$870
Last-minute flights from Portland to HeathrowDiscover last-minute flight deals from Portland to Heathrow. Data last updated October 1, 2026 and is based on user searches.
Discover last-minute flight deals from Portland to Heathrow. Data last updated October 1, 2026 and is based on user searches.
This United Airlines deal was found by Cheapflights users on 9/26. 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 10/57:25 pm -
1 stop10h 15m
Fri 10/96:50 am -
2 stops21h 38m
Deal found 9/26![United Airlines logo]()
$871
This KLM deal was found by Cheapflights users on 9/30. 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 10/612:42 pm -
1 stop13h 28m
Tue 10/2011:45 am -
2 stops17h 25m
Deal found 9/30![KLM logo]()
$862
This United Airlines deal was found by Cheapflights users on 9/25. 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.
Tue 10/66:00 am -
2 stops19h 30m
Sun 10/116:50 am -
2 stops22h 09m
Deal found 9/25![United Airlines logo]()
$875
This Delta deal was found by Cheapflights users on 9/30. 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 10/911:20 am -
1 stop14h 00m
Tue 10/278:40 am -
2 stops18h 38m
Deal found 9/30![Delta logo]()
$872
This United Airlines deal was found by Cheapflights users on 9/30. 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.
Sat 10/106:00 am -
1 stop20h 15m
Mon 10/267:30 am -
2 stops15h 22m
Deal found 9/30![United Airlines logo]()
$873
This Travelocity deal was found by Cheapflights users on 9/28. 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 Travelocity is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/216:00 am -
2 stops19h 30m
Sat 11/712:20 pm -
1 stop16h 23m
Deal found 9/28![Multiple Airlines logo]()
$855
This Delta deal was found by Cheapflights users on 9/28. 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 10/2112:42 pm -
2 stops15h 08m
Sat 11/78:40 am -
2 stops20h 30m
Deal found 9/28![Delta logo]()
$868
This Expedia deal was found by Cheapflights users on 9/28. 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 10/266:30 am -
1 stop11h 10m
Mon 11/28:05 am -
1 stop20h 38m
Deal found 9/28![JetBlue logo]()
$848
This Delta deal was found by Cheapflights users on 9/28. 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 10/2611:55 am -
1 stop15h 10m
Mon 11/26:30 am -
2 stops19h 30m
Deal found 9/28![Delta logo]()
$864
This United Airlines deal was found by Cheapflights users on 9/28. 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 10/263:41 pm -
2 stops15h 09m
Mon 11/212:05 pm -
2 stops16h 16m
Deal found 9/28![United Airlines logo]()
$870
This United Airlines deal was found by Cheapflights users on 9/27. 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.
Tue 10/2710:50 am -
2 stops15h 50m
Tue 11/1012:05 pm -
2 stops16h 16m
Deal found 9/27![United Airlines logo]()
$865
This United Airlines deal was found by Cheapflights users on 9/30. 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 10/282:05 pm -
1 stop16h 45m
Wed 11/412:05 pm -
2 stops16h 16m
Deal found 9/30![United Airlines logo]()
$861
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 October 1, 2026.
Search for one-way flight options from Portland to Heathrow. Find affordable one-way fares based on user searches. Data last updated October 1, 2026.
This Cheapflightsfares deal was found by Cheapflights users on 9/25. 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.
Sat 10/106:00 am -
1 stop9h 45m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/25![JetBlue logo]()
$320
This Orbitz deal was found by Cheapflights users on 9/25. 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 Orbitz is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/106:00 am -
2 stops34h 00m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/25![Air Canada logo]()
$321
This Delta deal was found by Cheapflights users on 9/25. 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.
Sun 11/156:00 am -
2 stops20h 05m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/25![Delta logo]()
$329
This Justfly.com deal was found by Cheapflights users on 9/25. 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 10/116:00 am -
2 stops34h 00m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/25![Air Canada logo]()
$333
This Air Canada deal was found by Cheapflights users on 9/25. 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.
Wed 11/118:49 am -
3 stops16h 41m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/25![Air Canada logo]()
$345
This Air Canada deal was found by Cheapflights users on 9/27. 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.
Sat 3/2011:17 am -
3 stops20h 03m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/27![Air Canada logo]()
$450
This Air Canada deal was found by Cheapflights users on 9/25. 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.
Sun 11/158:49 am -
3 stops17h 21m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/25![Air Canada logo]()
$1,026
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 October 1, 2026.
Most accurate provider | Ovago 3 stars |
|---|---|
Most trusted provider | Ovago 3 stars |
Round-trip from | $734 (United Airlines) |
One-way from | $320 (Cheapflightsfares) |
Popular in | June |
Cheapest in | February |
Average price | $1,192 |
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 October 1, 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
Quickest round-trip
PortlandLondon
PWM Portland - LHR London Heathrow
PWMLHR
Portland
Sun 10/11
6:00 am-8:45 pm
1 stop9h 45m
London Heathrow
Wed 12/31
12:00 am-6:00 pm
Nonstop0h 00m
$320
PortlandLondon
PWM Portland - LHR London Heathrow
PWMLHR
Portland
Sat 10/10
6:00 am-8:45 pm
1 stop9h 45m
London Heathrow
Wed 12/31
12:00 am-6:00 pm
Nonstop0h 00m
$320
PortlandLondon
PWM Portland - LHR London Heathrow
PWMLHR
Portland
Wed 11/11
6:30 am-9:40 pm
1 stop10h 10m
London Heathrow
Wed 12/31
12:00 am-6:00 pm
Nonstop0h 00m
$320
PortlandLondon
PWM Portland - LHR London Heathrow
PWMLHR
Portland
Wed 11/11
12:13 pm-7:00 am
2 stops13h 47m
London Heathrow
Wed 12/31
12:00 am-6:00 pm
Nonstop0h 00m
$329
PortlandLondon
PWM Portland - LHR London Heathrow
PWMLHR
Portland
Sun 11/15
6:00 am-6:35 am
1 stop19h 35m
London Heathrow
Wed 12/31
12:00 am-6:00 pm
Nonstop0h 00m
$329
PortlandLondon
PWM Portland - LHR London Heathrow
PWMLHR
Portland
Sun 11/15
6:00 am-7:05 am
2 stops20h 05m
London Heathrow
Wed 12/31
12:00 am-6:00 pm
Nonstop0h 00m
$329
PortlandLondon
PWM Portland - LHR London Heathrow
PWMLHR
Portland
Sat 3/20
4:50 pm-7:45 am
1 stop10h 55m
London Heathrow
Wed 12/31
12:00 am-6:00 pm
Nonstop0h 00m
$329
PortlandLondon
PWM Portland - LHR London Heathrow
PWMLHR
Portland
Sun 11/15
6:00 am-7:50 am
1 stop20h 50m
London Heathrow
Wed 12/31
12:00 am-6:00 pm
Nonstop0h 00m
$329
PortlandLondon
PWM Portland - LHR London Heathrow
PWMLHR
Portland
Sat 3/20
11:17 am-11:20 am
3 stops20h 03m
London Heathrow
Wed 12/31
12:00 am-6:00 pm
Nonstop0h 00m
$450
PortlandLondon
PWM Portland - LHR London Heathrow
PWMLHR
Portland
Sun 10/11
10:43 am-8:35 am
3 stops16h 52m
London Heathrow
Wed 12/31
12:00 am-6:00 pm
Nonstop0h 00m
$465
Showing 1-10 of 21 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 October.
| 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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