HomeSearch by dateVacation packagesHotelsFlight dealsCar rentalTravel tips & news
United Kingdom

$349+ 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 4/19. Fares are subject to change and may not be available on all flights or dates of travel.
PWM — LHR
Dec 6 — Dec 131
Sat 12/6
Sat 12/13
1 adult, Economy
We work with more than 300 partners to bring you better travel deals

Find cheap flights from Portland to United Kingdom 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 United Kingdom

Keep the following information in mind while searching for Portland to United Kingdom flight deals. Data was last updated November 6, 2025.

Most accurate provider

eDreams
3 stars

Most trusted provider

eDreams
3 stars

Round-trip from

$583
(Netflights)

One-way from

$349
(JetBlue)

Popular in

June

Cheapest in

October

Average price

$790
Provider with most accurate pricing for Portland-London (LON) flight deals.
Search Deals
Provider most trusted by Cheapflights users for Portland-London (LON) flights.
Search Deals
From Portland to United Kingdom
Search Deals
One-way flight from Portland to United Kingdom
Search Deals
Highest demand for flights based on searches. 17% potential increase in price ($181 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 3% potential price decrease ($32 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in November 2025
Search Deals

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 November 6, 2025.

This Netflights deal was found by Cheapflights users on 11/4. 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 Netflights is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/46:08 amPWM - LHR
1 stop20h 42mVirgin Atlantic
Thu 12/118:55 amLHR - PWM
1 stop18h 28mVirgin Atlantic
Deal found 11/4$583
This Delta deal was found by Cheapflights users on 11/4. 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 12/44:53 pmPWM - LHR
1 stop10h 52mDelta
Thu 12/118:55 amLHR - PWM
2 stops20h 04mDelta
Deal found 11/4$614
This Justfly.com deal was found by Cheapflights users on 11/4. 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.
Thu 12/44:53 pmPWM - LHR
1 stop10h 52mMultiple Airlines
Thu 12/1110:45 amLHR - PWM
1 stop16h 38mMultiple Airlines
Deal found 11/4$653
This Justfly.com deal was found by Cheapflights users on 11/4. 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.
Thu 12/42:34 pmPWM - LHR
2 stops13h 26mKLM
Thu 12/1111:45 amLHR - PWM
2 stops17h 14mKLM
Deal found 11/4$683
This Delta deal was found by Cheapflights users on 11/6. 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 11/81:27 pmPWM - LHR
1 stop11h 58mDelta
Sat 11/158:55 amLHR - PWM
2 stops19h 59mDelta
Deal found 11/6$689
This Expedia deal was found by Cheapflights users on 11/4. 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 12/46:15 amPWM - LCY
2 stops21h 35mKLM
Thu 12/119:20 amLCY - PWM
2 stops19h 39mKLM
Deal found 11/4$695
This KLM deal was found by Cheapflights users on 11/6. 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.
Sat 11/82:38 pmPWM - LHR
1 stop12h 27mKLM
Sat 11/1512:40 pmLHR - PWM
1 stop16h 14mKLM
Deal found 11/6$696
This KLM deal was found by Cheapflights users on 11/4. 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 11/71:27 pmPWM - LHR
1 stop14h 33mKLM
Sun 11/168:55 amLHR - PWM
1 stop18h 24mKLM
Deal found 11/4$697
This Delta deal was found by Cheapflights users on 11/4. 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 11/712:45 pmPWM - LHR
2 stops17h 55mDelta
Sun 11/163:50 pmLHR - PWM
2 stops25h 18mDelta
Deal found 11/4$701
This Scandinavian Airlines deal was found by Cheapflights users on 11/4. 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.
Thu 12/46:15 amPWM - LHR
2 stops22h 05mScandinavian Airlines
Thu 12/116:40 amLHR - PWM
3 stops22h 19mScandinavian Airlines
Deal found 11/4$716
This United Airlines deal was found by Cheapflights users on 11/4. 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 12/410:02 amPWM - LCY
2 stops18h 18mMultiple Airlines
Thu 12/115:40 pmLCY - PWM
2 stops30h 14mMultiple Airlines
Deal found 11/4$752
This KLM deal was found by Cheapflights users on 11/4. 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 11/182:30 pmPWM - EDI
1 stop14h 15mKLM
Sun 11/2311:45 amEDI - PWM
1 stop17h 09mKLM
Deal found 11/4$807

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 November 6, 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

Thu 12/4

4:53 pm-8:45 am

1 stop10h 52m

London Heathrow

Thu 12/11

8:55 am-11:59 pm

2 stops20h 04m

$614

PortlandLondon

PWM - LHR

PWMLHR

Portland

Wed 1/14

12:20 pm-8:45 am

1 stop15h 25m

London Heathrow

Mon 1/19

4:35 pm-12:20 am

1 stop12h 45m

$630

PortlandLondon

PWM - LHR

PWMLHR

Portland

Thu 12/4

2:34 pm-9:00 am

2 stops13h 26m

London Heathrow

Thu 12/11

12:30 pm-10:23 pm

1 stop14h 53m

$663

PortlandLondon

PWM - LHR

PWMLHR

Portland

Thu 12/4

2:34 pm-9:00 am

2 stops13h 26m

London Heathrow

Thu 12/11

11:45 am-11:59 pm

2 stops17h 14m

$683

PortlandLondon

PWM - LHR

PWMLHR

Portland

Wed 1/14

8:40 am-7:10 am

3 stops17h 30m

London Heathrow

Mon 1/19

6:00 pm-1:56 pm

2 stops24h 56m

$695

PortlandLondon

PWM - LCY

PWMLCY

Portland

Thu 12/4

6:15 am-8:50 am

2 stops21h 35m

London City

Thu 12/11

9:20 am-11:59 pm

2 stops19h 39m

$695

PortlandLondon

PWM - LHR

PWMLHR

Portland

Thu 12/4

6:15 am-9:20 am

2 stops22h 05m

London Heathrow

Thu 12/11

6:40 am-11:59 pm

3 stops22h 19m

$716

PortlandLondon

PWM - LHR

PWMLHR

Portland

Wed 3/18

11:17 am-9:20 am

2 stops18h 03m

London Heathrow

Wed 3/25

6:50 am-6:13 pm

2 stops15h 23m

$725

PortlandLondon

PWM - LHR

PWMLHR

Portland

Mon 4/20

2:20 pm-9:30 am

1 stop14h 10m

London Heathrow

Thu 4/23

11:55 am-11:36 pm

1 stop16h 41m

$747

PortlandLondon

PWM - LCY

PWMLCY

Portland

Thu 12/4

10:02 am-9:20 am

2 stops18h 18m

London City

Thu 12/11

5:40 pm-6:54 pm

2 stops30h 14m

$752

Flights are sorted by cheapest round-trip flights first.

Deals found on 11/6

Showing 1-10 of 60 results
1
2
3
...
6

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 November 6, 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 November 6, 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
8,004 reviews

Entertainment

7.9

Comfort

7.9

Boarding

8.2

Food

7.3

Crew

8.5

Overall

7.9

Reviews

1 / 20
6.0
Good

Jim,Nov 2025

AVL - ATL

The exit row seats without a seat in front are great for leg room but don’t have a fold out entertainment console so you’re forced to use the screen several feet in front of you (there is, at least, a remote). Best to bring a tablet loaded with entertainment or a book.
Delta
7.9
Good
8,004 reviews
Delta
7.9
Good
8,004 reviews

Entertainment

7.9

Comfort

7.9

Boarding

8.2

Food

7.3

Crew

8.5

Overall

7.9

Reviews

1 / 20
6.0
Good

Jim,Nov 2025

AVL - ATL

The exit row seats without a seat in front are great for leg room but don’t have a fold out entertainment console so you’re forced to use the screen several feet in front of you (there is, at least, a remote). Best to bring a tablet loaded with entertainment or a book.
United Airlines
7.4
Good
9,003 reviews
Delta
7.9
Good
8,004 reviews

Entertainment

7.9

Comfort

7.9

Boarding

8.2

Food

7.3

Crew

8.5

Overall

7.9

Reviews

1 / 20
6.0
Good

Jim,Nov 2025

AVL - ATL

The exit row seats without a seat in front are great for leg room but don’t have a fold out entertainment console so you’re forced to use the screen several feet in front of you (there is, at least, a remote). Best to bring a tablet loaded with entertainment or a book.
JetBlue
7.2
Good
2,907 reviews
Delta
7.9
Good
8,004 reviews

Entertainment

7.9

Comfort

7.9

Boarding

8.2

Food

7.3

Crew

8.5

Overall

7.9

Reviews

1 / 20
6.0
Good

Jim,Nov 2025

AVL - ATL

The exit row seats without a seat in front are great for leg room but don’t have a fold out entertainment console so you’re forced to use the screen several feet in front of you (there is, at least, a remote). Best to bring a tablet loaded with entertainment or a book.

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, KLM, and United Airlines fly from Portland, Maine to United Kingdom in about 10h 52m. The time it takes to get you to your destination can typically vary by up to 4h 58m. The distance from Portland, Maine to United Kingdom is about 3173 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 JetBlue. According to our data, you can fly for as low as $349. Users have also found prices from $399 and $406 on United Airlines and Delta, respectively.

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

    Most travelers choose Portland - London Heathrow, Portland - Edinburgh Turnhouse 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

Browse thousands of different options on Cheapflights for your next trip

Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.

Alternative routes for Portland to United Kingdom

See prices for flight routes from nearby airports that may be better suited for you.
Boston to Heathrow flights
Boston to Charles de Gaulle flights
Boston to Dublin flights
Boston to Gatwick flights
Boston to London City flights
Boston to Leonardo da Vinci/Fiumicino flights
Boston to Lisbon flights
Boston to Madrid flights
Boston to Stansted flights
Boston to Amsterdam flights
Boston to Orly flights
Boston to Luton flights
Boston to Istanbul flights
Boston to Frankfurt flights
Boston to Barcelona-El Prat flights
Boston to Athens flights
Boston to Zurich flights
Boston to Munich flights
Boston to Keflavik Intl flights
Boston to Edinburgh flights
Boston to Copenhagen flights
Boston to Ponta Delgada flights
Boston to Vicenza flights
Boston to Florence flights
Boston to Sabiha Gokcen flights
Boston to Malpensa flights
Boston to Beauvais-Tille flights
Boston to Prague flights
Boston to Vienna flights
Boston to Linate flights
Boston to Bruxelles-National flights
Boston to Shannon flights
Boston to Glasgow Intl flights
Boston to Porto flights
Boston to Berlin flights
Boston to Geneva flights
Boston to Málaga flights
Boston to Naples flights
Boston to Oslo Gardermoen flights
Boston to Basel flights
Boston to Bologna flights
Boston to Tirana flights
Boston to Frederic Chopin flights
Boston to Ciampino flights
Boston to Southend flights
Boston to Frankfurt-Hahn flights
Boston to Manchester flights
Boston to Krakow flights
Boston to Arlanda flights
Boston to Nice flights

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 November 6, 2025.
AirlineCheapestAverageFlexibilityOn-time
United AirlinesCheapest$648Average$1,024FlexibilityNo cancel feeOn-time69%
DeltaCheapest$683Average$913FlexibilityNo cancel feeOn-timeN/A
JetBlueCheapest$695Average$746FlexibilityNo cancel feeOn-time62%

100% Free

Cheapflights is completely free to use, so you can start saving the moment you arrive.

Book with Flexibility

Our users can plan ahead with confidence and find flights with no change fees

Travel Smart

Millions of people come to us for their flight needs every year. We help make travel planning easy by providing useful insights and data-driven graphs that can inform your decisions.