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$220+ Cheap flights from Portland, ME (PWM) to London (LON)

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 3/29. Fares are subject to change and may not be available on all flights or dates of travel.
PWM — LON
Jan 27 — Feb 31
Tue 1/27
Tue 2/3
1 adult, Economy
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Cheap flight deals from Portland to London

Best flights from Portland to London
Discover carefully curated flight deals from Portland to London that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated December 28, 2025.

This Kiwi.com deal was found by Cheapflights users on 12/27. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 1/268:40 amPWM - LHR
1 stop18h 45mAustrian Airlines
Mon 2/26:00 amLHR - PWM
2 stops17h 50mAustrian Airlines
Deal found 12/27$576
This United Airlines deal was found by Cheapflights users on 12/27. 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 2/104:10 pmPWM - LHR
1 stop14h 05mUnited Airlines
Tue 2/176:50 amLHR - PWM
2 stops17h 06mUnited Airlines
Deal found 12/27$630
This Virgin Atlantic deal was found by Cheapflights users on 12/25. 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 Virgin Atlantic is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 2/95:30 amPWM - LHR
1 stop22h 30mVirgin Atlantic
Mon 2/166:30 amLHR - PWM
2 stops21h 36mVirgin Atlantic
Deal found 12/25$631
This Delta deal was found by Cheapflights users on 12/27. 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.
Fri 2/202:35 pmPWM - LCY
2 stops12h 35mDelta
Fri 2/279:20 amLCY - PWM
2 stops19h 58mDelta
Deal found 12/27$666
This Trip.com deal was found by Cheapflights users on 12/27. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/36:00 amPWM - LGW
1 stop19h 20mMultiple Airlines
Tue 4/71:05 pmLGW - PWM
1 stop15h 42mMultiple Airlines
Deal found 12/27$738
This Turkish Airlines deal was found by Cheapflights users on 12/27. 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 Turkish Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/316:00 amPWM - LGW
2 stops29h 40mTurkish Airlines
Tue 4/147:00 amLGW - PWM
2 stops21h 36mTurkish Airlines
Deal found 12/27$1,045
This United Airlines deal was found by Cheapflights users on 12/25. 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.
Sun 2/83:42 pmPWM - LHR
1 stop12h 28mUnited Airlines
Sun 2/156:50 amLHR - PWM
2 stops17h 06mUnited Airlines
Deal found 12/25$630
This Delta deal was found by Cheapflights users on 12/27. 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.
Fri 2/62:35 pmPWM - LCY
2 stops13h 55mDelta
Fri 2/137:45 amLCY - PWM
2 stops20h 21mDelta
Deal found 12/27$666
This United Airlines deal was found by Cheapflights users on 12/27. 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.
Fri 2/204:15 pmPWM - LHR
1 stop14h 00mUnited Airlines
Fri 2/2712:05 pmLHR - PWM
2 stops16h 15mUnited Airlines
Deal found 12/27$630
This United Airlines deal was found by Cheapflights users on 12/27. 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.
Fri 2/64:10 pmPWM - LHR
1 stop14h 05mUnited Airlines
Fri 2/136:50 amLHR - PWM
2 stops36h 33mUnited Airlines
Deal found 12/27$630
This Kiwi.com deal was found by Cheapflights users on 12/26. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 3/2810:57 amPWM - LGW
1 stop19h 03mMultiple Airlines
Thu 4/22:00 pmLGW - PWM
1 stop24h 07mMultiple Airlines
Deal found 12/26$770
This United Airlines deal was found by Cheapflights users on 12/27. 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.
Mon 1/263:12 pmPWM - LHR
2 stops14h 38mUnited Airlines
Mon 2/26:50 amLHR - PWM
2 stops17h 02mUnited Airlines
Deal found 12/27$634
This Kiwi.com deal was found by Cheapflights users on 12/27. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 2/611:29 amPWM - LGW
2 stops17h 31mMultiple Airlines
Fri 2/132:00 pmLGW - PWM
1 stop25h 17mMultiple Airlines
Deal found 12/27$790
This Kiwi.com deal was found by Cheapflights users on 12/27. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 2/209:47 amPWM - LGW
1 stop19h 13mMultiple Airlines
Fri 2/272:00 pmLGW - PWM
1 stop25h 17mMultiple Airlines
Deal found 12/27$908
This Kiwi.com deal was found by Cheapflights users on 12/26. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 6/19:52 amPWM - LGW
1 stop19h 08mMultiple Airlines
Fri 6/52:00 pmLGW - PWM
1 stop26h 22mMultiple Airlines
Deal found 12/26$951
This Delta deal was found by Cheapflights users on 12/26. 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.
Sun 5/312:35 pmPWM - LCY
2 stops21h 05mDelta
Mon 6/88:25 amLCY - PWM
2 stops44h 34mDelta
Deal found 12/26$1,160
This Delta deal was found by Cheapflights users on 12/26. 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 6/26:30 amPWM - LCY
2 stops20h 25mDelta
Mon 6/810:00 amLCY - PWM
2 stops35h 15mDelta
Deal found 12/26$1,160
This Kiwi.com deal was found by Cheapflights users on 12/26. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 6/19:52 amPWM - LGW
1 stop19h 08mMultiple Airlines
Sun 6/72:00 pmLGW - PWM
1 stop24h 12mMultiple Airlines
Deal found 12/26$965
This Delta deal was found by Cheapflights users on 12/26. 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 6/32:35 pmPWM - LCY
2 stops37h 15mDelta
Tue 6/99:20 amLCY - PWM
2 stops35h 55mDelta
Deal found 12/26$1,160
This Icelandair deal was found by Cheapflights users on 12/27. 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 Icelandair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 1/263:30 pmPWM - LGW
2 stops14h 25mMultiple Airlines
Mon 2/211:55 amLGW - PWM
2 stops15h 20mMultiple Airlines
Deal found 12/27$1,020
This Delta deal was found by Cheapflights users on 12/26. 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 6/12:35 pmPWM - LCY
2 stops37h 15mDelta
Mon 6/89:20 amLCY - PWM
2 stops35h 55mDelta
Deal found 12/26$1,160
This Kiwi.com deal was found by Cheapflights users on 12/25. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 2/99:47 amPWM - LGW
1 stop19h 13mMultiple Airlines
Mon 2/167:40 pmLGW - PWM
2 stops43h 37mMultiple Airlines
Deal found 12/25$1,020
This Delta deal was found by Cheapflights users on 12/26. 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 6/22:35 pmPWM - LCY
2 stops37h 55mDelta
Tue 6/99:20 amLCY - PWM
2 stops43h 39mDelta
Deal found 12/26$1,160
This Kiwi.com deal was found by Cheapflights users on 12/26. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/305:01 pmPWM - LGW
2 stops35h 59mMultiple Airlines
Tue 6/92:00 pmLGW - PWM
1 stop25h 27mMultiple Airlines
Deal found 12/26$1,027
This Delta deal was found by Cheapflights users on 12/26. 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 5/282:35 pmPWM - LCY
2 stops13h 55mDelta
Wed 6/38:25 amLCY - PWM
2 stops36h 50mDelta
Deal found 12/26$1,230
This Delta deal was found by Cheapflights users on 12/26. 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 5/282:35 pmPWM - LCY
2 stops13h 55mDelta
Fri 6/510:00 amLCY - PWM
2 stops18h 59mDelta
Deal found 12/26$1,230
This American Airlines deal was found by Cheapflights users on 12/27. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 2/103:58 pmPWM - LCY
2 stops15h 42mMultiple Airlines
Tue 2/176:50 amLCY - PWM
2 stops16h 13mMultiple Airlines
Deal found 12/27$1,160
This Delta deal was found by Cheapflights users on 12/26. 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.
Sun 5/312:35 pmPWM - LCY
2 stops21h 05mDelta
Sat 6/612:10 pmLCY - PWM
2 stops33h 05mDelta
Deal found 12/26$1,230

Find flight deals from Portland to London

Discover tips and strategies to find the most affordable flight options for your journey from Portland (PWM) to London (LON). 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 December 28, 2025.

Most accurate provider

eDreams
3 stars

Most trusted provider

eDreams
3 stars

Round-trip from

$576
(Kiwi.com)

One-way from

$220
(British Airways)

Popular in

June

Cheapest in

October

Average price

$699
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 London (LON)
Search Deals
One-way flight from Portland to London (LON)
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 December 2025
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Portland to London 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 December 28, 2025.
Use the filters below to find and compare flights from Portland to London that are best for you.

Fly from

Portland

Fly to

London

Route

Depart

Return

Price

PortlandLondon

PWM - LHR

PWMLHR

Portland

Mon 1/26

8:40 am-8:25 am

1 stop18h 45m

London Heathrow

Mon 2/2

6:00 am-6:50 pm

2 stops17h 50m

$576

PortlandLondon

PWM - LHR

PWMLHR

Portland

Tue 2/10

4:10 pm-11:15 am

1 stop14h 05m

London Heathrow

Tue 2/17

6:50 am-6:56 pm

2 stops17h 06m

$630

PortlandLondon

PWM - LHR

PWMLHR

Portland

Sun 2/8

3:42 pm-9:10 am

1 stop12h 28m

London Heathrow

Sun 2/15

6:50 am-6:56 pm

2 stops17h 06m

$630

PortlandLondon

PWM - LHR

PWMLHR

Portland

Fri 2/20

4:15 pm-11:15 am

1 stop14h 00m

London Heathrow

Fri 2/27

12:05 pm-11:20 pm

2 stops16h 15m

$630

PortlandLondon

PWM - LHR

PWMLHR

Portland

Fri 2/6

4:10 pm-11:15 am

1 stop14h 05m

London Heathrow

Fri 2/13

6:50 am-2:23 pm

2 stops36h 33m

$630

PortlandLondon

PWM - LHR

PWMLHR

Portland

Mon 2/9

5:30 am-9:00 am

1 stop22h 30m

London Heathrow

Mon 2/16

6:30 am-11:06 pm

2 stops21h 36m

$631

PortlandLondon

PWM - LHR

PWMLHR

Portland

Mon 1/26

3:12 pm-10:50 am

2 stops14h 38m

London Heathrow

Mon 2/2

6:50 am-6:52 pm

2 stops17h 02m

$634

PortlandLondon

PWM - LCY

PWMLCY

Portland

Fri 2/20

2:35 pm-8:10 am

2 stops12h 35m

London City

Fri 2/27

9:20 am-12:18 am

2 stops19h 58m

$666

PortlandLondon

PWM - LCY

PWMLCY

Portland

Fri 2/6

2:35 pm-9:30 am

2 stops13h 55m

London City

Fri 2/13

7:45 am-11:06 pm

2 stops20h 21m

$666

PortlandLondon

PWM - LGW

PWMLGW

Portland

Fri 4/3

6:00 am-6:20 am

1 stop19h 20m

London Gatwick

Tue 4/7

1:05 pm-11:47 pm

1 stop15h 42m

$738

Flights are sorted by cheapest round-trip flights first.

Deals found on 12/26

Showing 1-10 of 45 results
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Compare providers for flights from Portland to London

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 London in December.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy2 starsTrust Score*3 stars
AranGrantPrice Accuracy2 starsTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*1 star
eDreamsPrice Accuracy3 starsTrust Score*3 stars

*The Trust Score is based on feedback from users after their booking experience. It measures overall satisfaction, helping us identify issues like hidden fees, problems during the ticketing process, and the quality of customer service. This score is our best indicator of the provider's quality and reliability.

  • Most accurate provider: When it comes to deals on Portland, Maine-London flights, users find the pricing of eDreams to be most consistent on Cheapflights vs. eDreams Users can find the same prices on Portland, Maine-London flight deals on Cheapflights vs. eDreams >95% of the time. Price accuracy is based on data collected from Portland, Maine-London flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Portland, Maine-London flights, Cheapflights users trust eDreams the most. eDreams 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 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 London

Have a flexible travel schedule? Discover the best time to fly to London 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 London

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

Currently, August is the cheapest month in which you can book a flight from Portland, Maine to London (average of $311). Flying from Portland, Maine to London in June is currently the most expensive (average of $561). 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.

How much does it cost to fly round-trip from Portland, Maine to London?

Reviews of airlines servicing London

Get insights into the airlines that provide service to London. 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 London. Reviews last updated December 28, 2025.
Get a feel of what it's like to fly with Delta, United Airlines, and JetBlue from Portland to London by reading reviews from past customers. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
Delta
7.9
Good
8,021 reviews

Crew

8.5

Food

7.3

Comfort

7.9

Overall

7.9

Boarding

8.1

Entertainment

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
8,021 reviews
Delta
7.9
Good
8,021 reviews

Crew

8.5

Food

7.3

Comfort

7.9

Overall

7.9

Boarding

8.1

Entertainment

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
9,116 reviews
Delta
7.9
Good
8,021 reviews

Crew

8.5

Food

7.3

Comfort

7.9

Overall

7.9

Boarding

8.1

Entertainment

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
2,902 reviews
Delta
7.9
Good
8,021 reviews

Crew

8.5

Food

7.3

Comfort

7.9

Overall

7.9

Boarding

8.1

Entertainment

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 London. 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 London?

    Portland (PWM) is the airport you will fly out of if you book a flight from Portland to London. You should not have trouble finding flights to London from Portland; the airport handles an average of 0 outbound flights to London per day. You should also have plenty of airline options to choose from since 2 airlines have flights from the Portland airport to London. It is only a 2.9 mi journey to Portland (PWM) from Portland’s city center.

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

    There are many flights that can get you from Portland, Maine to London in 12h 35m. Fly via Austrian Airlines, United Airlines, or Delta to get the fastest option. There are 3193 mi between Portland, Maine and London. This flight may include one or multiple stops.

  • What are the cheapest airlines flying from Portland, Maine to London round-trip?

    Flying on United Airlines is currently your cheapest option to London, with prices starting at $648. Another option worth looking into is Delta, starting at $765 round trip. United Airlines is 24% cheaper than the average price of flights available within the next 90 days to this destination.

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

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

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

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

  • How can I find direct flights from Portland to London?

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

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

    Yes. Cheapflights offers flight deals from Portland to London 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 London?

    Currently, August is the cheapest month in which you can book a flight from Portland, Maine to London (average of $311). Flying from Portland, Maine to London in June is currently the most expensive (average of $561). 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

Traveling to a place near London?

Book flights to London if you plan to visit one of these locations
Ilford
Hounslow
Southend-on-Sea
Harrow
Eastleigh
Dartford
Dover
Winchester
Croydon
Hayes
Orpington
Watford
Borehamwood
Aylesbury
Chipping Norton
Horley
Kingston upon Thames
Folkestone
Eastbourne
Sutton

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.

Top 2 airlines flying from Portland to London

Discover the top 2 airlines that operate flights from Portland to London. 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 December 28, 2025.
AirlineCheapestAverageFlexibilityOn-time
United AirlinesCheapest$648Average$874FlexibilityNo cancel feeOn-time69%
DeltaCheapest$765Average$1,083FlexibilityNo cancel feeOn-timeN/A

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