PWM - LON

$419 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 2/12. 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 24% 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
$629
Typical prices: $753-$789
Virgin Atlantic
Wed 2/4Wed 2/11
PWM - LHR • 1 stop
Cheapest one-way
$503
Delta
Thu 2/12
PWM - LCY • 2 stops
Top airlines
Virgin Atlantic
Cheapest • from $629 (round-trip)
Delta
Best reviews • 7.9 score
Airline reviews
Airline reviews
+1
+1
Airline reviews
Airline reviews
+1
When to travel
October
Cheapest • 28% price drop
April
Most popular
Good to know
Good to know
+1
+1
Good to know
Good to know
+1
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

Wed, Feb 4 - Wed, Feb 11
Virgin Atlantic Logo
5:30 am - 9:00 am
PWM
-
LHR
22h 30m1 stop
Virgin Atlantic Logo
6:30 am - 10:27 pm
LHR
-
PWM
20h 57m2 stops
$629Virgin Atlantic
Wed, Feb 4 - Wed, Feb 11
Virgin Atlantic Logo
5:30 am - 7:55 am
PWM
-
LHR
21h 25m2 stops
Virgin Atlantic Logo
6:30 am - 10:27 pm
LHR
-
PWM
20h 57m2 stops
$634Virgin Atlantic
Tue, Mar 31 - Tue, Apr 14
Delta Logo
2:30 pm - 10:15 am
PWM
-
LHR
14h 45m1 stop
Delta Logo
8:40 am - 12:46 am
LHR
-
PWM
21h 06m2 stops
$645Delta
Tue, Mar 31 - Tue, Apr 14
Delta Logo
4:48 pm - 1:10 pm
PWM
-
LHR
15h 22m2 stops
Delta Logo
9:55 am - 12:46 am
LHR
-
PWM
19h 51m2 stops
$649Delta
Wed, Feb 4 - Wed, Feb 11
KLM Logo
2:35 pm - 10:15 am
PWM
-
LHR
14h 40m1 stop
KLM Logo
12:40 pm - 12:20 am
LHR
-
PWM
16h 40m1 stop
$657KLM
Tue, Mar 31 - Tue, Apr 14
KLM Logo
12:50 pm - 8:55 am
PWM
-
LHR
15h 05m1 stop
KLM Logo
4:05 pm - 12:46 am
LHR
-
PWM
13h 41m1 stop
$673KLM
Wed, Feb 4 - Wed, Feb 11
Austrian Airlines Logo
11:10 am - 9:10 am
PWM
-
LHR
17h 00m1 stop
Austrian Airlines Logo
6:00 am - 11:21 pm
LHR
-
PWM
22h 21m2 stops
$684Austrian Airlines
Tue, Jan 20 - Thu, Jan 29
United Airlines Logo
7:27 pm - 11:05 am
PWM
-
LHR
10h 38m1 stop
United Airlines Logo
6:50 am - 6:50 pm
LHR
-
PWM
17h 00m2 stops
$691United Airlines
Tue, Jan 20 - Thu, Jan 29
United Airlines Logo
2:31 pm - 10:25 am
PWM
-
LHR
14h 54m2 stops
United Airlines Logo
11:10 am - 11:30 pm
LHR
-
PWM
17h 20m2 stops
$696United Airlines
Sat, May 9 - Sun, May 17
Delta Logo
2:35 pm - 8:10 pm
PWM
-
LHR
24h 35m1 stop
Delta Logo
6:30 am - 11:59 pm
LHR
-
PWM
22h 29m2 stops
$700Delta
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 February.

What is the cheapest month to fly from Portland to London?

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from Portland to London, removes the top 0.1% to account for outliers, and then takes the median of all values for each month.

The cheapest month for flights from Portland to London is October, where tickets cost $619 (return) on average. On the other hand, the most expensive months are June and July, where the average cost of round-trip tickets is $1,208 and $1,188 respectively.

Good to know

Low seasonFebruary
Best time to beat the crowds with an average 17% drop in price.
Most popular time to fly and prices are also 13% lower on average.

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 $523 for a one-way ticket and $629 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?

    SkyTeam, and Star Alliance are the airline alliances operating flights between Portland and London, with SkyTeam being the most commonly used for this route.

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

    The two airlines most popular with KAYAK users for flights from Portland to London are Delta and United Airlines. With an average price for the route of $769 and an overall rating of 7.9, Delta is the most popular choice. United Airlines is also a great choice for the route, with an average price of $764 and an overall rating of 7.4.

  • 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 3 airlines serving 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.
7.9
DeltaOverall score based on 8015 reviews
7.9Entertainment
8.1Boarding
8.5Crew
7.9Comfort
7.3Food
Airline reviews

The plant way delayed departing by 3 hours. It was an old airplane with broken seats and armrests. The bathroom made a hollering sound. A really crappy flight experience and travel day all around.

2.0 MediocrePeter, Dec 2025
JFK - MEM
Read more Delta reviews

The plant way delayed departing by 3 hours. It was an old airplane with broken seats and armrests. The bathroom made a hollering sound. A really crappy flight experience and travel day all around.

Flight delays both to Detroits and return flight . The flight to Detroit was associated with mechanical difficulty

I am extremely disappointed that delta internal pilot manuals now refer to the Gulf of Mexico as the “gulf of America”. You can bow down to the Orange turd on your own. I will never fly delta again

Wasn't a Delta issue I don't think, but seems there was a Delta flight at each of the 2 Dallas airports at the same exact time, both to Atlanta. I was evidently booked on the one at Love Airport, but the Carey transport shuttle took me to DFW instead and I ended up missing the flight by just a few minutes. Was able to book a Southwest flight from Love Airport, but was a big loss of time and an inconvenience.

Great. I had to modify a flight. That was easy and free. Thank You

I noticed that the planes seem to be outdated. There was no entertainment per se. Also, the waiting area did not have any working electrical outlets

None of the airplane features were available during the flight.

Original flight was cancelled and when i was rebooked by the airline, they couldn't seat me in the same type of seat as I had originally booked (went from window/aisle to middle/middle and one was a bulkhead seat, and other wasn't in the same class)

Lady Pilot was perfect in every way wheels up to wheels down communication, professionalism, excellent on time departure and on time arrival, excellent communication! Fantastic job with Superb attitude!!

The food is terrible. The staff is wonderful. Comfort is good.

I liked the snacks and the flight attendants were friendly.

Gate agent at Frankfurt was terrible. She denied PRE boarding even as it was printed on the boarding pass. Refused to look at the boarding pass and literally shouting for no reason. Frankfurt airport has horrible and rude staff who avoids trying to answer any question at all. Overall, horrible experience.

The Crew and the food was the worst I ever had in Business Class. First they told us there were no space for carry on. It was plenty of space over our 2 row seats, we had to ask to let us travel with it which was accepted. They were aware that we had to run for the connection due to the previous flight delay. Have us one hour waiting for more customers and not even offer a glass of water. Then started the service and they started to serve other passengers drinks in business and did not offer any drinks until they serve our pre ordered meal and I ask for something to drink. I had to wait until they finished to serve all passengers until Inget something. The crew was the worts I ever had for Business Class in my life.

Very turbulent trip made it pretty bearable, plus the lack of refreshments served and the lack of any air conditioning before takeoff which took an hour or more.

Flight was late - I was downgraded from first class to coach

Not good - outbound flight was delayed and missed my connection even though I got to the gate after running through the airport - the agent would not let me on because the door was closed (flight had not left). There was no notification from United - overall experience was very disappointing. Additionally, I was downgraded from first class to coach on the alternative flight

The flight was on time. I generally don’t drink or eat on short flights and the seats were good and the flight attendants were friendly. That’s all I expect

It was nice to have gotten up upgraded to first class with a meal on a three hour flight

Not great experience - we were super late boarding due to issues with aircraft. Then when we finally all got onboard and seated and they started taxiing out to the runway they just stopped then turned around and went back to the airport. Apparently the crew “ran out of time” to legally fly us. They mentioned that they were about 2 minutes away from taking off. I understand the rules and safety but kinda wonder why they would have bothered boarding us in the first place? Had to go all the way back and de plane and then wait in a HUGE line to get a hotel (this is somewhere around 2:30am) finally got to hotel by Uber (no shuttle after 20min so gave up) and they ended up putting us all back on the same aircraft at 10am next morning so got about 2.5 hours sleep. They did give us. $250 credit, but it was a São Paulo Brazil flight out of Dulles. The flight and everything was fine.

United overall experience is great these days. Airport experience was very organized. Staff on flight were great. App and information as good as it gets.

It was good. I prefer JB over other airlines.I just wish we had headphones for the films, but other than that - good.

The ride share experience in JFK is terrible. After traveling on a flight, then you need to take a subway to the last stop to get an uber or lyft. Unacceptable. Bad job JetBlue for permitting JFK and Port Authority to do this to your passengers.

Checking In on JetBlue site was impossible. It hung up on REAL ID. Even my Global Entry did not help. Luckily, on Kayak site it was a breeze. Entire flight the temperature was COLD! Otherwise the crew was great!

The flight was two hours late due to a computer fault and resulting maintenance. Nothing was offered as compensation beyond bottles of water during the time we were deplaned and waiting in the terminal.

Very pleasant flight attendants. Gate crew rather loud chatting with each other.

Four plus hour flight delay in New York caused us to take off after 11:30pm. We didn’t arrive at our hotel until five hours after check in. Started the trip off feeling exhausted.

Plane was in bad shape. TV’s and WiFi didn’t work. Plane need a refresh. Not enough room for bags.

There was a fowl odour coming from the lavatory the entire flight

Everything was great. I liked the text updates so that I never miss a gate change & I have all the latest info.

I don’t usually fly budget airlines or airlines in the United States. It was as good as any other airline. The seats are comfortable and the airline attendants are not rude & surly. Very nice flight (s).

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

Information on your arrival and departure airports