$330+ 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 12/1. Fares are subject to change and may not be available on all flights or dates of travel.
PWM — LHR
Sep 30 — Oct 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
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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 August 31, 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 August 31, 2026.
This United Airlines deal was found by Cheapflights users on 8/30. 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.
Tue 11/102:05 pm -
1 stop11h 35m
Tue 11/246:50 am -
2 stops17h 12m
Deal found 8/30![United Airlines logo]()
$867
This Delta deal was found by Cheapflights users on 8/26. 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.
Wed 10/144:47 pm -
2 stops14h 18m
Fri 11/68:40 am -
2 stops17h 20m
Deal found 8/26![Delta logo]()
$873
This Expedia deal was found by Cheapflights users on 8/30. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 9/276:00 am -
1 stop9h 45m
Sun 10/48:15 am -
1 stop20h 39m
Deal found 8/30![JetBlue logo]()
$874
This United Airlines deal was found by Cheapflights users on 8/29. 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 10/133:41 pm -
2 stops13h 34m
Tue 10/201:50 pm -
2 stops14h 38m
Deal found 8/29![United Airlines logo]()
$876
This Justfly.com deal was found by Cheapflights users on 8/27. 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 Justfly.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/105:50 am -
2 stops20h 20m
Tue 11/249:00 am -
2 stops43h 21m
Deal found 8/27![Air Canada logo]()
$878
This Cheapflightsfares deal was found by Cheapflights users on 8/26. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/216:00 am -
1 stop9h 45m
Sun 10/411:55 am -
1 stop16h 59m
Deal found 8/26![JetBlue logo]()
$879
This Cheapflightsfares deal was found by Cheapflights users on 8/28. 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 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
Mon 10/128:15 am -
1 stop20h 39m
Deal found 8/28![JetBlue logo]()
$880
This United Airlines deal was found by Cheapflights users on 8/28. 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 10/126:00 am -
1 stop10h 35m
Mon 10/195:55 pm -
2 stops29h 17m
Deal found 8/28![United Airlines logo]()
$881
This Air Canada deal was found by Cheapflights users on 8/30. 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 Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/108:49 am -
3 stops18h 41m
Tue 11/176:00 am -
3 stops22h 21m
Deal found 8/30![Air Canada logo]()
$884
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 August 31, 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 August 31, 2026.
This United Airlines deal was found by Cheapflights users on 8/30. 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.
Tue 11/103:41 pm -
1 stop13h 44m
Tue 11/176:50 am -
2 stops21h 31m
Deal found 8/30![United Airlines logo]()
$867
This Delta deal was found by Cheapflights users on 8/26. 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.
Wed 10/146:01 am -
1 stop20h 14m
Fri 11/68:40 am -
2 stops17h 20m
Deal found 8/26![Delta logo]()
$868
This United Airlines deal was found by Cheapflights users on 8/30. 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 10/146:00 am -
1 stop9h 40m
Wed 10/216:50 am -
2 stops17h 34m
Deal found 8/30![United Airlines logo]()
$867
This Delta deal was found by Cheapflights users on 8/26. 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.
Tue 11/1012:45 pm -
2 stops15h 15m
Tue 11/2410:00 am -
2 stops18h 31m
Deal found 8/26![Delta logo]()
$873
This United Airlines deal was found by Cheapflights users on 8/28. 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.
Tue 11/102:05 pm -
1 stop11h 35m
Tue 11/246:50 am -
2 stops17h 12m
Deal found 8/28![United Airlines logo]()
$868
This Delta deal was found by Cheapflights users on 8/26. 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.
Tue 11/1012:45 pm -
2 stops15h 15m
Tue 11/178:40 am -
2 stops20h 39m
Deal found 8/26![Delta logo]()
$873
This Delta deal was found by Cheapflights users on 8/26. 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.
Thu 10/155:28 pm -
1 stop11h 52m
Fri 11/610:00 am -
2 stops16h 00m
Deal found 8/26![Delta logo]()
$898
Last-minute flights from Portland to HeathrowDiscover last-minute flight deals from Portland to Heathrow. Data last updated August 31, 2026 and is based on user searches.
Discover last-minute flight deals from Portland to Heathrow. Data last updated August 31, 2026 and is based on user searches.
This Delta deal was found by Cheapflights users on 8/29. 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 9/212:47 pm -
2 stops16h 43m
Wed 9/99:55 am -
2 stops18h 34m
Deal found 8/29![Delta logo]()
$932
This Cheapflightsfares deal was found by Cheapflights users on 8/28. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/126:00 am -
1 stop9h 45m
Wed 9/1611:55 am -
1 stop16h 59m
Deal found 8/28![JetBlue logo]()
$908
This Delta deal was found by Cheapflights users on 8/28. 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 9/126:02 am -
1 stop9h 08m
Wed 9/169:55 am -
2 stops19h 01m
Deal found 8/28![Delta logo]()
$928
This Cheapflightsfares deal was found by Cheapflights users on 8/26. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/216:00 am -
1 stop9h 45m
Sun 10/411:55 am -
1 stop16h 59m
Deal found 8/26![JetBlue logo]()
$879
This Delta deal was found by Cheapflights users on 8/26. 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.
Mon 9/216:02 am -
1 stop9h 08m
Sun 10/48:40 am -
2 stops20h 16m
Deal found 8/26![Delta logo]()
$929
This Cheapflightsfares deal was found by Cheapflights users on 8/29. 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 9/266:00 am -
1 stop9h 45m
Sat 10/311:55 am -
1 stop16h 59m
Deal found 8/29![JetBlue logo]()
$878
This United Airlines deal was found by Cheapflights users on 8/29. 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 9/263:41 pm -
1 stop10h 34m
Sat 10/36:50 am -
2 stops17h 34m
Deal found 8/29![United Airlines logo]()
$927
This Expedia deal was found by Cheapflights users on 8/30. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 9/276:00 am -
1 stop9h 45m
Sun 10/48:15 am -
1 stop20h 39m
Deal found 8/30![JetBlue logo]()
$874
This United Airlines deal was found by Cheapflights users on 8/30. 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.
Sun 9/276:00 am -
1 stop9h 40m
Sun 10/46:50 am -
2 stops21h 38m
Deal found 8/30![United Airlines logo]()
$897
This Expedia deal was found by Cheapflights users on 8/30. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 9/276:00 am -
2 stops19h 30m
Sun 10/49:30 am -
2 stops15h 52m
Deal found 8/30![Air Canada logo]()
$921
This United Airlines deal was found by Cheapflights users on 8/30. 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.
Tue 9/293:41 pm -
1 stop10h 34m
Tue 10/66:50 am -
2 stops18h 32m
Deal found 8/30![United Airlines logo]()
$867
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 August 31, 2026.
Search for one-way flight options from Portland to Heathrow. Find affordable one-way fares based on user searches. Data last updated August 31, 2026.
This Delta deal was found by Cheapflights users on 8/29. 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 12/14:00 pm -
1 stop12h 25m
Deal found 8/29![Delta logo]()
$330
This Expedia deal was found by Cheapflights users on 8/30. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/196:00 am -
1 stop22h 30m
Deal found 8/30![JetBlue logo]()
$340
This British Airways deal was found by Cheapflights users on 8/26. 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 British Airways is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 12/255:25 am -
1 stop20h 10m
Deal found 8/26![Multiple Airlines logo]()
$426
This United Airlines deal was found by Cheapflights users on 8/30. 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 10/1911:35 am -
2 stops14h 20m
Deal found 8/30![United Airlines logo]()
$463
This Air Canada deal was found by Cheapflights users on 8/30. 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 Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/198:03 am -
3 stops17h 27m
Deal found 8/30![Air Canada logo]()
$472
This Air Canada deal was found by Cheapflights users on 8/26. 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 Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 12/256:00 am -
3 stops20h 10m
Deal found 8/26![Air Canada logo]()
$505
This Air Canada deal was found by Cheapflights users on 8/29. 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 12/16:00 am -
3 stops20h 10m
Deal found 8/29![Air Canada logo]()
$665
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 August 31, 2026.
Most accurate provider | Ovago 3 stars |
|---|---|
Most trusted provider | Ovago 3 stars |
Round-trip from | $867 (United Airlines) |
One-way from | $330 (Delta) |
Popular in | June |
Cheapest in | February |
Average price | $1,210 |
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 August 31, 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
Tue 11/10
3:41 pm-10:25 am
1 stop13h 44m
London Heathrow
Tue 11/17
6:50 am-11:21 pm
2 stops21h 31m
$867
Quickest round-trip
PortlandLondon
PWM Portland - LHR London Heathrow
PWMLHR
Portland
Wed 10/14
6:00 am-8:40 pm
1 stop9h 40m
London Heathrow
Wed 10/21
6:50 am-7:24 pm
2 stops17h 34m
$867
PortlandLondon
PWM Portland - LHR London Heathrow
PWMLHR
Portland
Wed 10/14
6:01 am-7:15 am
1 stop20h 14m
London Heathrow
Fri 11/6
8:40 am-9:00 pm
2 stops17h 20m
$868
PortlandLondon
PWM Portland - LHR London Heathrow
PWMLHR
Portland
Tue 11/10
2:05 pm-6:40 am
1 stop11h 35m
London Heathrow
Tue 11/24
6:50 am-7:02 pm
2 stops17h 12m
$868
PortlandLondon
PWM Portland - LHR London Heathrow
PWMLHR
Portland
Tue 11/10
12:45 pm-9:00 am
2 stops15h 15m
London Heathrow
Tue 11/24
10:00 am-11:31 pm
2 stops18h 31m
$873
PortlandLondon
PWM Portland - LHR London Heathrow
PWMLHR
Portland
Tue 11/10
12:45 pm-9:00 am
2 stops15h 15m
London Heathrow
Tue 11/17
8:40 am-12:19 am
2 stops20h 39m
$873
PortlandLondon
PWM Portland - LHR London Heathrow
PWMLHR
Portland
Thu 10/15
5:28 pm-10:20 am
1 stop11h 52m
London Heathrow
Fri 11/6
10:00 am-9:00 pm
2 stops16h 00m
$898
Cheapest one-way
PortlandLondon
PWM Portland - LHR London Heathrow
PWMLHR
Portland
Tue 12/1
12:49 pm-11:40 am
2 stops17h 51m
$330
PortlandLondon
PWM Portland - LHR London Heathrow
PWMLHR
Portland
Mon 10/19
6:00 am-9:30 am
1 stop22h 30m
$340
PortlandLondon
PWM Portland - LHR London Heathrow
PWMLHR
Portland
Fri 12/25
5:25 am-6:35 am
1 stop20h 10m
$426
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 August.
| 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.
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 August 31, 2026.
Read through reviews of airlines operating flights from Portland to London Heathrow Airport, such as United Airlines. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Crew
8.1
Comfort
7.3
Entertainment
7.1
Food
6.7
Boarding
7.7
Overall
7.4
Reviews
1 / 20
4.0
OkayChris,Aug 2026
MIA - ORD
Crew
8.1
Comfort
7.3
Entertainment
7.1
Food
6.7
Boarding
7.7
Overall
7.4
Reviews
1 / 20
4.0
OkayChris,Aug 2026
MIA - ORD
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
Winchester
Gatwick
Hounslow
Harrow
Eastleigh
Wembley
Southend-on-Sea
Basingstoke
Watford
Northampton
Dartford
Croydon
Chipping Norton
Kingston upon Thames
Eastbourne
Slough
Stansted
Sutton
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Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.
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Other flights to Heathrow
Explore flights to Heathrow departing from other origins. Flights are based on user searches made on Cheapflights and were last updated on August 31, 2026.
Portland and Heathrow flights
Browse other Portland and Heathrow flight options. Last updated on August 31, 2026.
Other flights from Portland
Browse through other flights departing from Portland. Flights are based on user searches made on Cheapflights and were last updated on August 31, 2026.
Popular flight searches
Check out other popular destinations found by fellow travelers in 2026
Top airline flying from Portland to Heathrow
Discover the top airline that operate flights from Portland 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 7,457,451 searches. Data last updated August 31, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$752 | Average$1,192 | FlexibilityNo cancel fee | On-time69% |