PWM - LON

$305 Find Cheap Flights from Portland to London

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from Portland to London departing on 9/14. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
1 adult
1 adult, Economy, 0 bags

KAYAK searches hundreds of travel sites at once for deals on flights to London

 
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Portland to London, as well as popular online travel agencies
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Portland to London, as well as popular online travel agencies
Travelers love KAYAK
41,299,237 searches in the past 7 days on KAYAK

Save 23% or moreCompare multiple travel sites with one search.

Track pricesNot ready to book? Create a price alert for when prices drop.

Bundle and saveSave money when you bundle your flight + hotel.

Filter your dealsChoose cabin class, free Wi-Fi and more.

Everything you should know

Cheapest round-trip
$795
Scandinavian Airlines
Mon 5/4Mon 5/11
PWM - LHR • 2 stops
Cheapest one-way
$305
American Airlines
Mon 9/14
PWM - LHR • 1 stop
Top airlines
Cheapest • from $795 (round-trip)
Best reviews • 7.4 score
Airline reviews
Airline reviews
+1
+1
Airline reviews
Airline reviews
+1
Nonstop flights
Not available
There are currently no direct flights between Portland and London. You'll need at least 1 connection.
Insights
Insights
Insights
Insights
Top layover airports
Cheapest • Avg $725 (round-trip)
Shortest trip • 9h 52m (one-way)
Insights
Insights
Insights
Insights
Start a new search
KAYAK searches 100s of sites at once to find you the best travel deals.
We hope you love your trip to London!
Flight Deals
Booking Insights
Flight Deals

Cheap Flights from Portland to London (PWM-LON)

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from Portland to London that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.
Discover the best prices for you by selecting your travel dates on KAYAK.

Recent round-trip flight deals from Portland to London

Mon, May 4 - Mon, May 11
Scandinavian Airlines Logo
2:51 pm - 4:00 pm
PWM
-
LHR
20h 09m
2 stops
Scandinavian Airlines Logo
7:05 am - 12:43 am
LHR
-
PWM
22h 38m
2 stops
$795Scandinavian Airlines
Fri, May 8 - Wed, May 13
Turkish Airlines Logo
6:00 am - 1:10 pm
PWM
-
LGW
26h 10m
2 stops
Turkish Airlines Logo
7:05 am - 11:36 pm
LGW
-
PWM
21h 31m
2 stops
$807Turkish Airlines
Wed, May 6 - Mon, May 11
Turkish Airlines Logo
6:00 am - 9:55 am
PWM
-
LGW
22h 55m
2 stops
Turkish Airlines Logo
2:05 pm - 11:36 pm
LGW
-
PWM
38h 31m
2 stops
$833Turkish Airlines
Mon, May 4 - Mon, May 11
JetBlue Logo
6:00 am - 9:30 am
PWM
-
LHR
22h 30m
1 stop
JetBlue Logo
8:15 am - 11:36 pm
LHR
-
PWM
20h 21m
1 stop
$834JetBlue
Mon, May 4 - Mon, May 11
JetBlue Logo
6:00 am - 9:30 am
PWM
-
LHR
22h 30m
1 stop
JetBlue Logo
8:15 am - 11:36 pm
LHR
-
PWM
20h 21m
1 stop
$835JetBlue
Sat, Jun 6 - Fri, Jun 12
Multiple Airlines Logo
5:01 pm - 10:00 am
PWM
-
LGW
35h 59m
2 stops
Multiple Airlines Logo
2:00 pm - 9:12 am
LGW
-
PWM
24h 12m
1 stop
$943Multiple Airlines
Sat, Jun 6 - Fri, Jun 12
Multiple Airlines Logo
5:01 pm - 10:00 am
PWM
-
LGW
35h 59m
2 stops
Multiple Airlines Logo
2:00 pm - 9:12 am
LGW
-
PWM
24h 12m
1 stop
$953Multiple Airlines
Sun, May 3 - Sun, May 10
Delta Logo
2:51 pm - 9:50 am
PWM
-
LCY
13h 59m
2 stops
Delta Logo
1:45 pm - 12:43 am
LCY
-
PWM
15h 58m
2 stops
$1,018Delta
Wed, Apr 1 - Wed, Apr 8
Delta Logo
4:48 pm - 4:00 pm
PWM
-
LGW
18h 12m
2 stops
Delta Logo
10:25 am - 11:59 pm
LGW
-
PWM
18h 34m
2 stops
$1,034Delta
Thu, May 14 - Mon, May 18
Air Europa Logo
12:55 pm - 8:50 am
PWM
-
LCY
14h 55m
2 stops
Air Europa Logo
8:15 pm - 11:09 pm
LCY
-
PWM
31h 54m
2 stops
$1,334Air Europa
Booking Insights

KAYAK's insights & trends for Portland to London flights

Get data-powered insights and trends into flights from Portland to London to help you find the cheapest flights, the best time to fly and much more.

How much is a round-trip flight from Portland, Maine to London?

This analysis is based on the cheapest round-trip price found on KAYAK in the last 12 months by searching for a flight from Portland, Maine to London departing in May.

Good to know

Low seasonOctober
Cheapest flight$305
Best time to beat the crowds with an average 28% drop in price.
Most popular time to fly and prices are also 10% lower on average.
Flight from Portland to London Heathrow Airport

When to book flights from Portland to London

Are your dates flexible? Find out the best times to travel from Portland to London based on our flight data from the last year. Discover the cheapest month and even day to fly.
Estimated round-trip price
KAYAK looks at all historical flight data for each date to provide a predicted price for one-way trips or round-trips with a duration up to 40 days. While we try to provide actual minimum prices for each date, some prices are predictions and actual prices may differ.

FAQs for booking flights from Portland to London

  • What is the cheapest flight from Portland to London?

    In the last 3 days, the lowest price for a flight from Portland to London was $305 for a one-way ticket and $795 for a round-trip.

  • Do I need a passport to fly between Portland and London?

    Yes

  • Which aircraft models fly most regularly from Portland to London?

    We unfortunately don’t have that data for this specific route.

  • Which airline alliances offer flights from Portland to London?

    Star Alliance is the only airline alliance operating flights between Portland and London.

  • Which is the best airline for flights from Portland to London, United Airlines or American Airlines?

    The two airlines most popular with KAYAK users for flights from Portland to London are United Airlines and American Airlines. With an average price for the route of $746 and an overall rating of 7.4, United Airlines is the most popular choice. American Airlines is also a great choice for the route, with an average price of $1,047 and an overall rating of 7.1.

  • How does KAYAK find such low prices on flights from Portland to London?

    KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Portland to London.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Portland to London?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to London from Portland is likely to change within 7 days, so travelers know whether to wait or book now.

  • What is the Hacker Fare option on flights from Portland to London?

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to London with an airline and back to Portland with another airline.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Portland to London?

    Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to London from Portland up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

Reviews of the top airlines flying from Portland to London

 
See real verified KAYAK customer reviews for airlines flying from Portland to London. Airline scores are aggregated from all reviews left by passengers on KAYAK after flying with an airline. KAYAK doesn’t show reviews that are older than 5 years. Learn how KAYAK collects reviews.
Need help choosing which airline to fly with from Portland to London? KAYAK airline reviews give an overall score for each airline based on loads of factors, including comfort, boarding, in-flight entertainment and more, to make your decision easier. See airline scores according to verified KAYAK customer reviews.
7.4
United AirlinesOverall score based on 9455 reviews
8.1Crew
7.7Boarding
7.1Entertainment
6.6Food
7.3Comfort
Airline reviews

ticket agent lady wás very helpful , she arranged wheel chair for my elderly mother

8.0 ExcellentLaba, Mar 2026
DEN - YEG
Read more United Airlines reviews

ticket agent lady wás very helpful , she arranged wheel chair for my elderly mother

Didn't make the flight because the first leg of my flight was canceled and the next leg was already booked.

My flight was canceled a few hours before boarding. I was rebooked on Copa airlines and missed an important meeting .

Good quick flight on a small but comfortable plane. I'm 6'3 and had plenty of space.

Experience was great - no complaints. Took off on time, landed early. Got to the gate relatively quickly - took a little bit of extra time to deplane but nothing excessive.

Business class seats felt very cramped compared to other airlines.

Economy plus was so cramped I could not use my laptop. It was beyond bad.

OK, we were delayed and had to de plane and reboard.

United is one airline which regardless of how many separate United tickets in existence, if one flight breaks down, the airline will take care of all the flights.

Both our flights were delayed. Almost didn’t get in the second flight. Staff was rude to the bone.

My flight to London from Philadelphia was cancelled due to weather.

Disliked having to wait a little longer to disembark from the plan when we landed in London

Food should be better quality. Video screens have poor resolution and the library of movies is poor. The other airlines are much better.

The trip was smooth but the crew were very abrupt, snatching things before finished and being quite snappy when asked questions.

My wife and I love to travel, so we fly a lot. We've already logged 381,075 miles and with practically every major airline. But this flight was very disappointing. It started off well, with no delays and a new plane. But when lunchtime approached, all that good impression was ruined. Instead of white tablecloths, we were offered small, dark placemats, which, as it turned out, were perfectly adequate for the food. All the food offered—and my wife and I only took fish, and the meat—was not just bad, it was downright disgusting and not heated enough. The same applies to the appetizers. This was the first time in many years of traveling that we've been offered such disgusting food.

Lost luggage stuck no clothes and no word after 2 days leaving on cruise no stuff or clothes

Don’t know they cancelled the flight day before I was to leave. They sent a email at 9:00 pm at night saying they cancelled. That is the smooth way to say we don’t want your business! I think they didn’t have enough people booking so they cancelled the flight! It’s all about the money anymore there is no honesty in business.

The flight was canceled 3 hours after original take off time

Pathetic check in experience at JFK. Everything is self check in. Not enough staff present to help with when the check in process or the kiosk gets stuck. Staff present not welcoming or pleasant at all. On the other hand the NY based flight crew was great. Courteous and friendly throughout the flight. Special meals leave a lot to be desired. Kids meals should be made available when kids are flying and same goes for special kids meals too.

The plane was probably full boarding was easy. We were able to check our carry-on luggage for free. It was a return flight through Philly to LA. Never saw a stewardess do a demonstration of emergency Procedures. I think my flight was pretty full

Everything you need to know for your flight from Portland to London

Information on your arrival and departure airports