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$343+ Cheap flights from Portland, ME (PWM) to the United Kingdom

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 1/15. Fares are subject to change and may not be available on all flights or dates of travel.
PWM — LHR
Nov 28 — Dec 51
Fri 11/28
Fri 12/5
1 adult, Economy
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Cheap flight deals from Portland to United Kingdom

Keep the following information in mind while searching for Portland to United Kingdom flight deals. Data was last updated October 29, 2025.

Most accurate provider

eDreams
3 stars

Most trusted provider

eDreams
3 stars

Round-trip from

$592
(Delta)

One-way from

$343
(FlightHub)

Popular in

June

Cheapest in

October

Average price

$638
Provider with most accurate pricing for Portland-London (LON) flight deals.
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Provider most trusted by Cheapflights users for Portland-London (LON) flights.
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From Portland to United Kingdom
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One-way flight from Portland to United Kingdom
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Highest demand for flights based on searches. 17% potential increase in price ($181 potential increase over avg. RT price).
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Cheapest flight prices on average. 3% potential price decrease ($32 potential savings vs. average RT price).
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Average for round-trip flights in October 2025
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Find flight deals from Portland to United Kingdom

Cheapest flights from Portland to United Kingdom
Explore the most affordable flight options available from Portland to United Kingdom. Find the lowest fares from popular airlines and budget airlines, with prices last updated on October 29, 2025.

This Delta deal was found by Cheapflights users on 10/27. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/111:25 pmPWM - LHR
1 stop12h 00mDelta
Tue 11/186:20 amLHR - PWM
2 stops22h 34mDelta
Deal found 10/27$592
This Delta deal was found by Cheapflights users on 10/28. 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.
Sun 11/96:00 amPWM - LHR
1 stop19h 20mDelta
Tue 11/1811:45 amLHR - PWM
2 stops17h 09mDelta
Deal found 10/28$593
This Delta deal was found by Cheapflights users on 10/28. 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 11/102:30 pmPWM - LHR
2 stops15h 20mDelta
Tue 11/1810:00 amLHR - PWM
2 stops18h 19mDelta
Deal found 10/28$597
This American Airlines deal was found by Cheapflights users on 10/29. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/116:00 amPWM - LHR
1 stop19h 35mAmerican Airlines
Tue 11/187:50 amLHR - PWM
2 stops15h 20mAmerican Airlines
Deal found 10/29$617
This United Airlines deal was found by Cheapflights users on 10/29. 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.
Wed 11/54:40 pmPWM - LHR
1 stop13h 35mUnited Airlines
Wed 11/126:35 amLHR - PWM
2 stops32h 29mUnited Airlines
Deal found 10/29$619
This Expedia deal was found by Cheapflights users on 10/28. 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.
Tue 11/116:00 amPWM - LHR
2 stops24h 20mAir Canada
Tue 11/181:25 pmLHR - PWM
2 stops33h 23mAir Canada
Deal found 10/28$620
This United Airlines deal was found by Cheapflights users on 10/27. 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 11/112:20 pmPWM - LHR
2 stops13h 05mUnited Airlines
Tue 11/186:35 amLHR - PWM
2 stops17h 24mUnited Airlines
Deal found 10/27$623
This Air Canada deal was found by Cheapflights users on 10/27. 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.
Sun 11/96:00 amPWM - LHR
2 stops22h 20mAir Canada
Tue 11/189:00 amLHR - PWM
2 stops37h 48mAir Canada
Deal found 10/27$626
This Air Canada deal was found by Cheapflights users on 10/28. 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 Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 11/77:46 pmPWM - LHR
2 stops56h 34mAir Canada
Tue 11/189:00 amLHR - PWM
2 stops37h 48mAir Canada
Deal found 10/28$631
This United Airlines deal was found by Cheapflights users on 10/29. 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.
Wed 11/53:20 pmPWM - LCY
2 stops16h 35mMultiple Airlines
Wed 11/129:50 amLCY - PWM
2 stops19h 09mMultiple Airlines
Deal found 10/29$664
This United Airlines deal was found by Cheapflights users on 10/27. 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.
Wed 11/267:22 pmPWM - LCY
2 stops17h 18mMultiple Airlines
Wed 12/35:40 pmLCY - PWM
2 stops30h 14mMultiple Airlines
Deal found 10/27$714
This Delta deal was found by Cheapflights users on 10/28. 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.
Tue 11/252:30 pmPWM - LCY
2 stops13h 20mDelta
Tue 12/28:40 amLCY - PWM
2 stops20h 19mDelta
Deal found 10/28$814

Cheapflights Fare Finder

 
Customize your flight search to find flights from Portland to United Kingdom that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated October 29, 2025.
Use the filters below to find and compare flights from Portland to the United Kingdom that are best for you.

Fly from

Portland

Fly to

United Kingdom

Route

Depart

Return

Price

PortlandLondon

PWM - LHR

PWMLHR

Portland

Tue 11/11

12:48 pm-8:45 am

1 stop14h 57m

London Heathrow

Tue 11/18

11:45 am-11:54 pm

2 stops17h 09m

$593

PortlandLondon

PWM - LHR

PWMLHR

Portland

Sun 11/9

6:35 am-6:55 am

1 stop19h 20m

London Heathrow

Tue 11/18

8:40 am-11:19 pm

2 stops19h 39m

$593

PortlandLondon

PWM - LHR

PWMLHR

Portland

Wed 11/12

11:25 am-6:55 am

1 stop14h 30m

London Heathrow

Tue 11/18

10:00 am-11:19 pm

2 stops18h 19m

$593

PortlandLondon

PWM - LHR

PWMLHR

Portland

Mon 11/10

6:35 am-6:20 am

1 stop18h 45m

London Heathrow

Tue 11/18

8:40 am-11:54 pm

2 stops20h 14m

$593

PortlandLondon

PWM - LHR

PWMLHR

Portland

Tue 11/11

1:25 pm-7:50 am

1 stop13h 25m

London Heathrow

Tue 11/18

2:30 pm-11:54 pm

1 stop14h 24m

$599

PortlandEdinburgh

PWM - EDI

PWMEDI

Portland

Wed 1/21

2:35 pm-10:40 am

2 stops15h 05m

Edinburgh Turnhouse

Sun 1/25

5:45 am-12:20 am

2 stops23h 35m

$629

PortlandLondon

PWM - LCY

PWMLCY

Portland

Wed 11/26

7:22 pm-5:40 pm

2 stops17h 18m

London City

Wed 12/3

5:40 pm-6:54 pm

2 stops30h 14m

$714

PortlandEdinburgh

PWM - EDI

PWMEDI

Portland

Wed 1/21

3:12 pm-7:55 am

1 stop11h 43m

Edinburgh Turnhouse

Sun 1/25

9:25 am-6:52 pm

2 stops14h 27m

$768

PortlandManchester

PWM - MAN

PWMMAN

Portland

Fri 3/27

9:34 am-10:20 am

2 stops20h 46m

Manchester

Tue 3/31

6:05 am-7:24 pm

2 stops18h 19m

$777

PortlandLondon

PWM - LCY

PWMLCY

Portland

Tue 11/25

2:30 pm-8:50 am

2 stops13h 20m

London City

Tue 12/2

8:40 am-11:59 pm

2 stops20h 19m

$814

Flights are sorted by cheapest round-trip flights first.

Deals found on 10/29

Showing 1-10 of 46 results
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Best time to book a flight from Portland to United Kingdom

Have a flexible travel schedule? Discover the best time to fly to United Kingdom from Portland with our price prediction graph.
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Cheapflights Insights

Everything you need to know about your flight from Portland to the United Kingdom

What is the cheapest month to book a flight from Portland, Maine to United Kingdom?

Currently, August is the cheapest month in which you can book a flight from Portland, Maine to United Kingdom (average of $311). Flying from Portland, Maine to United Kingdom in July is currently the most expensive (average of $473). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

What is the cheapest time of day to fly from PWM to GB?

Find hourly flight availability from Portland to United Kingdom. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated October 29, 2025.

Unlike in the afternoon, when flights are generally more expensive, you can save up to 13% on flights from Portland, Maine to United Kingdom by exploring options for tickets in the evening.

What is the cheapest day to fly from Portland, Maine to United Kingdom?

Use this chart to determine the cheapest time to fly round-trip from Portland to United Kingdom. Price data was last updated on December 16, 2024.

Travelers seeking maximum savings on their Portland, Maine to United Kingdom flight should consider departing on Monday at noon when fares are most often at their lowest. Friday evenings flights should be avoided if possible as fares are typically the most expensive at this time.

Reviews of airlines servicing United Kingdom

Get insights into the airlines that provide service to United Kingdom. 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 United Kingdom. Reviews last updated October 29, 2025.
Read through reviews of airlines operating flights from Portland to the United Kingdom, such as Delta, United Airlines, and JetBlue. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Delta
7.9
Good
7,993 reviews

Boarding

8.2

Comfort

7.9

Food

7.3

Overall

7.9

Crew

8.5

Entertainment

7.9

Reviews

1 / 20
8.0
Excellent

Matthew,Oct 2025

GSP - ATL

This is always a full flight since it is the connecting route to primary destinations through Atlanta. That said, the crew handles the full load well. Not much more to say, it is a short flight with no in-flight services due to the length.
Delta
7.9
Good
7,993 reviews
Delta
7.9
Good
7,993 reviews

Boarding

8.2

Comfort

7.9

Food

7.3

Overall

7.9

Crew

8.5

Entertainment

7.9

Reviews

1 / 20
8.0
Excellent

Matthew,Oct 2025

GSP - ATL

This is always a full flight since it is the connecting route to primary destinations through Atlanta. That said, the crew handles the full load well. Not much more to say, it is a short flight with no in-flight services due to the length.
United Airlines
7.4
Good
8,998 reviews
Delta
7.9
Good
7,993 reviews

Boarding

8.2

Comfort

7.9

Food

7.3

Overall

7.9

Crew

8.5

Entertainment

7.9

Reviews

1 / 20
8.0
Excellent

Matthew,Oct 2025

GSP - ATL

This is always a full flight since it is the connecting route to primary destinations through Atlanta. That said, the crew handles the full load well. Not much more to say, it is a short flight with no in-flight services due to the length.
JetBlue
7.2
Good
2,906 reviews
Delta
7.9
Good
7,993 reviews

Boarding

8.2

Comfort

7.9

Food

7.3

Overall

7.9

Crew

8.5

Entertainment

7.9

Reviews

1 / 20
8.0
Excellent

Matthew,Oct 2025

GSP - ATL

This is always a full flight since it is the connecting route to primary destinations through Atlanta. That said, the crew handles the full load well. Not much more to say, it is a short flight with no in-flight services due to the length.

Related info for your journey

Find useful and relevant information for your journey from Portland to United Kingdom. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • What airport do you fly from for flights from Portland to United Kingdom?

    For a flight from Portland to United Kingdom, you will be flying from Portland. Portland (PWM) is just 2.9 mi from the center of the city.

  • How long is the flight from Portland, Maine to United Kingdom?

    Airlines like Delta, United Airlines, and American Airlines fly from Portland, Maine to United Kingdom in about 11h 43m. The time it takes to get you to your destination can typically vary by up to 4h 37m. The distance from Portland, Maine to United Kingdom is about 2973 mi. Both multi-stop and nonstop flights can be found to your destination and back.

  • What are the cheapest airlines to fly from Portland, Maine to United Kingdom one-way?

    For one-way options, check prices for Scandinavian Airlines. According to our data, you can fly for as low as $343. Users have also found prices from $390 and $432 on Air Canada and United Airlines, respectively.

  • What are the most popular routes from Portland, Maine to United Kingdom?

    Most travelers choose Portland - London Heathrow, Portland - London Gatwick or Portland - London City when deciding on the best route from Portland, Maine to United Kingdom.

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

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

  • How can I find direct flights from Portland to United Kingdom?

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

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

    Yes. Cheapflights offers flight deals from Portland to United Kingdom by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

  • What is the cheapest month to book a flight from Portland, Maine to United Kingdom?

    Currently, August is the cheapest month in which you can book a flight from Portland, Maine to United Kingdom (average of $311). Flying from Portland, Maine to United Kingdom in July is currently the most expensive (average of $473). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

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Alternative routes for Portland to United Kingdom

See prices for flight routes from nearby airports that may be better suited for you.
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Top 3 airlines flying from Portland to United Kingdom

Discover the top 3 airlines that operate flights from Portland to United Kingdom. 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 2,558,603 searches. Data last updated October 29, 2025.
AirlineCheapestAverageFlexibilityOn-time
United AirlinesCheapest$648Average$1,024FlexibilityNo cancel feeOn-time69%
DeltaCheapest$683Average$913FlexibilityNo cancel feeOn-timeN/A
JetBlueCheapest$695Average$746FlexibilityNo cancel feeOn-time62%

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