$411+ 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 9/13. Fares are subject to change and may not be available on all flights or dates of travel.
PWM — LHR
Sep 22 — Sep 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 August 23, 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 23, 2026.
This Delta deal was found by Cheapflights users on 8/18. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/104:03 pm -
1 stop13h 27m
Tue 11/2410:00 am -
2 stops18h 55m
Deal found 8/18![Delta logo]()
$867
This United Airlines deal was found by Cheapflights users on 8/22. 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 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 8/22![United Airlines logo]()
$868
This Delta deal was found by Cheapflights users on 8/18. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/1012:50 pm -
2 stops17h 50m
Tue 11/176:30 am -
2 stops22h 25m
Deal found 8/18![Delta logo]()
$871
This Delta deal was found by Cheapflights users on 8/22. 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.
Tue 10/64:15 pm -
2 stops16h 30m
Tue 10/139:55 am -
2 stops19h 15m
Deal found 8/22![Delta logo]()
$873
This Delta deal was found by Cheapflights users on 8/20. 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 10/146:04 am -
1 stop21h 46m
Tue 10/2011:30 am -
2 stops17h 40m
Deal found 8/20![Delta logo]()
$874
This Cheapflightsfares deal was found by Cheapflights users on 8/20. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/156:00 am -
1 stop9h 45m
Mon 10/198:15 am -
1 stop20h 37m
Deal found 8/20![JetBlue logo]()
$887
This Cheapflightsfares deal was found by Cheapflights users on 8/21. 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.
Thu 10/156:00 am -
1 stop9h 45m
Sun 10/1811:55 am -
1 stop16h 57m
Deal found 8/21![JetBlue logo]()
$888
This JetBlue deal was found by Cheapflights users on 8/20. 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 JetBlue is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/166:00 am -
1 stop9h 45m
Sun 10/1811:55 am -
1 stop16h 57m
Deal found 8/20![JetBlue logo]()
$897
This Delta deal was found by Cheapflights users on 8/21. 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.
Sun 10/44:20 pm -
1 stop11h 30m
Sun 10/1111:45 am -
2 stops17h 25m
Deal found 8/21![Delta logo]()
$898
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 23, 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 23, 2026.
This United Airlines deal was found by Cheapflights users on 8/20. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 2/85:06 pm -
1 stop11h 04m
Wed 2/106:50 am -
2 stops16h 23m
Deal found 8/20![United Airlines logo]()
$754
This Delta deal was found by Cheapflights users on 8/20. 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 11/104:03 pm -
1 stop13h 27m
Tue 11/2410:00 am -
2 stops18h 55m
Deal found 8/20![Delta logo]()
$867
This United Airlines deal was found by Cheapflights users on 8/21. 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.
Tue 11/103:41 pm -
1 stop13h 44m
Tue 11/176:50 am -
2 stops21h 31m
Deal found 8/21![United Airlines logo]()
$867
This Delta deal was found by Cheapflights users on 8/18. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/1012:50 pm -
2 stops17h 50m
Tue 11/176:30 am -
2 stops22h 25m
Deal found 8/18![Delta logo]()
$871
This United Airlines deal was found by Cheapflights users on 8/22. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/102:05 pm -
2 stops14h 05m
Tue 11/246:50 am -
2 stops17h 12m
Deal found 8/22![United Airlines logo]()
$872
This Delta deal was found by Cheapflights users on 8/22. 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.
Tue 10/64:15 pm -
2 stops16h 30m
Tue 10/139:55 am -
2 stops19h 15m
Deal found 8/22![Delta logo]()
$873
This Delta deal was found by Cheapflights users on 8/18. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/106:04 am -
1 stop9h 06m
Thu 10/159:55 am -
2 stops19h 15m
Deal found 8/18![Delta logo]()
$897
Last-minute flights from Portland to HeathrowDiscover last-minute flight deals from Portland to Heathrow. Data last updated August 23, 2026 and is based on user searches.
Discover last-minute flight deals from Portland to Heathrow. Data last updated August 23, 2026 and is based on user searches.
This Air Canada deal was found by Cheapflights users on 8/18. 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 Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/206:00 am -
2 stops34h 00m
Thu 9/1012:40 pm -
2 stops39h 52m
Deal found 8/18![Air Canada logo]()
$933
This Air Canada deal was found by Cheapflights users on 8/18. 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 Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/206:00 am -
2 stops34h 00m
Tue 9/82:05 pm -
2 stops38h 27m
Deal found 8/18![Air Canada logo]()
$936
This Expedia deal was found by Cheapflights users on 8/19. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/202:40 pm -
1 stop25h 05m
Mon 8/248:15 am -
1 stop33h 15m
Deal found 8/19![JetBlue logo]()
$938
This JetBlue deal was found by Cheapflights users on 8/18. 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 JetBlue is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 8/216:10 am -
1 stop9h 35m
Thu 9/1011:55 am -
1 stop16h 59m
Deal found 8/18![JetBlue logo]()
$897
This United Airlines deal was found by Cheapflights users on 8/18. 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.
Sun 8/235:52 am -
2 stops19h 03m
Mon 9/76:50 am -
2 stops22h 09m
Deal found 8/18![United Airlines logo]()
$931
This Delta deal was found by Cheapflights users on 8/18. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/2411:50 am -
2 stops14h 50m
Tue 9/88:40 am -
2 stops20h 16m
Deal found 8/18![Delta logo]()
$935
This Expedia deal was found by Cheapflights users on 8/18. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/32:40 pm -
1 stop25h 05m
Thu 9/108:15 am -
1 stop20h 39m
Deal found 8/18![JetBlue logo]()
$902
This Delta deal was found by Cheapflights users on 8/18. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/32:53 pm -
1 stop10h 27m
Thu 9/109:55 am -
2 stops19h 01m
Deal found 8/18![Delta logo]()
$927
This Cheapflightsfares deal was found by Cheapflights users on 8/19. 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 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 8/19![JetBlue logo]()
$887
This Delta deal was found by Cheapflights users on 8/22. 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.
Sat 9/126:02 am -
1 stop9h 08m
Wed 9/169:55 am -
2 stops18h 33m
Deal found 8/22![Delta logo]()
$928
This Delta deal was found by Cheapflights users on 8/22. 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.
Wed 9/1611:50 am -
2 stops16h 10m
Mon 9/2111:45 am -
2 stops17h 11m
Deal found 8/22![Delta logo]()
$937
This Cheapflightsfares deal was found by Cheapflights users on 8/23. 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.
Mon 9/216:00 am -
1 stop9h 45m
Sat 9/2611:55 am -
1 stop16h 59m
Deal found 8/23![JetBlue logo]()
$888
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 23, 2026.
Search for one-way flight options from Portland to Heathrow. Find affordable one-way fares based on user searches. Data last updated August 23, 2026.
This Expedia deal was found by Cheapflights users on 8/20. 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.
Sun 9/136:00 am -
1 stop22h 30m
Deal found 8/20![JetBlue logo]()
$411
This United Airlines deal was found by Cheapflights users on 8/21. 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 10/186:00 am -
1 stop18h 55m
Deal found 8/21![United Airlines logo]()
$460
This Expedia deal was found by Cheapflights users on 8/20. 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.
Sun 9/136:00 am -
2 stops30h 45m
Deal found 8/20![Multiple Airlines logo]()
$464
This Scandinavian Airlines deal was found by Cheapflights users on 8/21. 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 Scandinavian Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 10/186:04 am -
3 stops22h 16m
Deal found 8/21![Scandinavian Airlines logo]()
$2,584
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 23, 2026.
Most accurate provider | Ovago 3 stars |
|---|---|
Most trusted provider | Ovago 3 stars |
Round-trip from | $754 (United Airlines) |
One-way from | $411 (Expedia) |
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 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
Cheapest round-trip
Quickest round-trip
PortlandLondon
PWM Portland - LHR London Heathrow
PWMLHR
Portland
Mon 2/8
5:06 pm-9:10 am
1 stop11h 04m
London Heathrow
Wed 2/10
6:50 am-6:13 pm
2 stops16h 23m
$754
PortlandLondon
PWM Portland - LHR London Heathrow
PWMLHR
Portland
Tue 11/10
4:03 pm-10:30 am
1 stop13h 27m
London Heathrow
Tue 11/24
10:00 am-11:55 pm
2 stops18h 55m
$867
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
PortlandLondon
PWM Portland - LHR London Heathrow
PWMLHR
Portland
Tue 11/10
12:50 pm-11:40 am
2 stops17h 50m
London Heathrow
Tue 11/17
6:30 am-11:55 pm
2 stops22h 25m
$871
PortlandLondon
PWM Portland - LHR London Heathrow
PWMLHR
Portland
Tue 11/10
2:05 pm-9:10 am
2 stops14h 05m
London Heathrow
Tue 11/24
6:50 am-7:02 pm
2 stops17h 12m
$872
PortlandLondon
PWM Portland - LHR London Heathrow
PWMLHR
Portland
Tue 10/6
4:15 pm-1:45 pm
2 stops16h 30m
London Heathrow
Tue 10/13
9:55 am-12:10 am
2 stops19h 15m
$873
PortlandLondon
PWM Portland - LHR London Heathrow
PWMLHR
Portland
Sat 10/10
6:04 am-8:10 pm
1 stop9h 06m
London Heathrow
Thu 10/15
9:55 am-12:10 am
2 stops19h 15m
$897
Cheapest one-way
PortlandLondon
PWM Portland - LHR London Heathrow
PWMLHR
Portland
Sun 9/13
6:00 am-9:30 am
1 stop22h 30m
$411
Quickest one-way
PortlandLondon
PWM Portland - LHR London Heathrow
PWMLHR
Portland
Sun 10/18
6:00 am-5:55 am
1 stop18h 55m
$460
PortlandLondon
PWM Portland - LHR London Heathrow
PWMLHR
Portland
Sun 9/13
6:00 am-5:45 pm
2 stops30h 45m
$464
Showing 1-10 of 11 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 23, 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.
Boarding
7.7
Entertainment
7.1
Comfort
7.3
Crew
8.1
Food
6.7
Overall
7.4
Reviews
1 / 20
4.0
OkayChris,Aug 2026
MIA - ORD
Boarding
7.7
Entertainment
7.1
Comfort
7.3
Crew
8.1
Food
6.7
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
Wembley
Eastleigh
Harrow
Southend-on-Sea
Watford
Northampton
Dartford
Croydon
Chipping Norton
Kingston upon Thames
Eastbourne
Slough
Stansted
Sutton
Luton
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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 23, 2026.
Portland and Heathrow flights
Browse other Portland and Heathrow flight options. Last updated on August 23, 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 23, 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 23, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$752 | Average$1,192 | FlexibilityNo cancel fee | On-time69% |