PWM - LON

$348 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 4/3. 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
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Everything you should know

Cheapest round-trip
$648
Typical prices: $774-$968
Delta
Wed 5/6Wed 5/13
PWM - LHR • 1 stop
Cheapest one-way
$348
JetBlue
Fri 4/3
PWM - LHR • 1 stop
Top airlines
Delta
Cheapest • from $648 (round-trip)
Delta
Best reviews • 7.9 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
New York (JFK)
Cheapest • Avg $703 (round-trip)
Newark (EWR)
Shortest trip • 9h 52m (one-way)
Insights
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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, May 6 - Wed, May 13
Delta Logo
2:51 pm - 10:20 am
PWM
-
LHR
14h 29m
1 stop
Delta Logo
9:55 am - 12:34 am
LHR
-
PWM
19h 39m
2 stops
$648Delta
Wed, May 6 - Wed, May 13
United Airlines Logo
3:39 pm - 10:40 am
PWM
-
LHR
14h 01m
2 stops
United Airlines Logo
6:50 am - 6:23 pm
LHR
-
PWM
16h 33m
2 stops
$652United Airlines
Sat, Mar 28 - Fri, Apr 10
Air Canada Logo
6:00 am - 8:00 pm
PWM
-
LHR
34h 00m
2 stops
Air Canada Logo
2:05 pm - 11:28 pm
LHR
-
PWM
38h 23m
2 stops
$658Air Canada
Thu, Mar 19 - Thu, Mar 26
United Airlines Logo
3:44 pm - 6:20 am
PWM
-
LHR
10h 36m
1 stop
United Airlines Logo
7:40 am - 9:11 pm
LHR
-
PWM
17h 31m
1 stop
$660United Airlines
Wed, May 6 - Mon, May 11
United Airlines Logo
4:45 pm - 11:45 am
PWM
-
LHR
14h 00m
1 stop
United Airlines Logo
5:50 pm - 6:23 pm
LHR
-
PWM
29h 33m
2 stops
$661United Airlines
Wed, May 6 - Mon, May 11
United Airlines Logo
6:00 am - 9:35 pm
PWM
-
LHR
10h 35m
1 stop
United Airlines Logo
5:50 pm - 6:23 pm
LHR
-
PWM
29h 33m
2 stops
$662United Airlines
Thu, Mar 19 - Thu, Mar 26
Air Canada Logo
6:00 am - 11:20 am
PWM
-
LHR
25h 20m
2 stops
Air Canada Logo
9:00 am - 10:51 pm
LHR
-
PWM
17h 51m
2 stops
$669Air Canada
Wed, May 6 - Mon, May 11
JetBlue Logo
6:00 am - 8:45 pm
PWM
-
LHR
9h 45m
1 stop
JetBlue Logo
8:15 am - 11:36 pm
LHR
-
PWM
20h 21m
1 stop
$671JetBlue
Wed, May 6 - Wed, May 13
KLM Logo
2:51 pm - 8:50 am
PWM
-
LHR
12h 59m
1 stop
KLM Logo
9:20 am - 11:18 pm
LHR
-
PWM
18h 58m
1 stop
$677KLM
Thu, Jun 11 - Wed, Jun 17
Delta Logo
2:35 pm - 9:25 am
PWM
-
LGW
13h 50m
2 stops
Delta Logo
10:25 am - 11:59 pm
LGW
-
PWM
18h 34m
2 stops
$1,083Delta
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$348
Best time to beat the crowds with an average 27% drop in price.
Most popular time to fly and prices are also 8% 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 $348 for a one-way ticket and $648 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, 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 $753 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 $749 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 4 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 8228 reviews
7.8Entertainment
7.9Comfort
8.5Crew
7.2Food
8.1Boarding
Airline reviews

Flight crew issues delayed my flight by 2 1/2 hours. Causing me to miss my connection.

2.0 MediocreCason, Feb 2026
EWR - ATL
Read more Delta reviews

Flight crew issues delayed my flight by 2 1/2 hours. Causing me to miss my connection.

The staff on board and gate was nice - a welcome change from the usual. We also arrived early, which was a great benefit, given that it takes 30 minutes plus to get bags at SRQ.

The staff was frielndly. The plane was terrible, it was too small and should be decommissioned. There were no back seat screens at all. The only beverages we had a choice from was coffee, tea or water. The only bathroom in the back was behind the flight attendant's jump seat and wasn't working. And I literally felt like I was sitting on top of the guy next to me. It was terribly hot in the plane and we had to sit on the tarmac in Chicago for 1/2 hour due to congestion in Mpls. Wouldn't they have know that before they even boarded us so that we could have sat in comfort in the terminal?

Never got on it. Was re-routed through Detroit and am still in airports 12 hours later waiting for my connecting plane to arrive.

Delta has too many delays now days. It is 1:06 am now. I was supposed to land in Norfolk at 10:30 pm. I got re-booked through Detroit and I’m still in Detroit. I hope to be landed in Norfolk by 3am. I’ve been in airports for 12 hours as of right now. There is a weather delay now but most delays lately have been maintenance.

Very Very late. Subsequent flights left an hour before ours

This is my worse experience with Delta. My colleagues and I were traveling to ICT for work. Usually we connect in Dallas, but this year we decided to book with Delta and connect in Atlanta. We were excited to fly with Delta because we hear great things and Delta is one of my top choices when choosing an airline for travel. On the connecting flights to and from Wichita/Atlanta - it felt hot and uncomfortable on the plane. The plane to ICT was smaller and older and did not have any wi-fi or entertainment. The most terrible experience was at boarding in Atlanta both times traveling to Wichita and then back to Tampa. First on our flight from ATL to ICT - the attendant scanning our boarding pass made us go back to the line when we went up to scan our passes to wait. After a few minutes, she allowed us to come back up to scan but then she asked what boarding zone we were. We told her zone 5, and since we were standing on the wrong side of the small rope partition, she made us go back to stand on the right side. There was another gentleman that came up to board and scan his pass, and she mentioned he was also on the wrong side but she let him go through. Our group had to walk back and forth for no reason, causing an unnecessary delay to board the plane. We have never experienced anything like this, especially when the boarding area was completely empty and everyone already boarded since boarding was earlier than the original boarding time. On our flight from ATL to TPA, the attendants scanning our boarding passes had us scan our passes twice, not explaining to us what was going on. They automatically started tagging our carry on bags and did not explain to us or tell us what was going on and why this was happening. Obviously we knew our bags were being forced to check in but with no reason. There was no announcement or mention and I have never had anyone force me to check in my bag before boarding the plane. We assumed the overhead bins were full but when we boarded the plane, there was a lot of empty bins and a lot of spaces to put our bags. We all were disappointed and frustrated with Delta and will be hesitant to fly Delta again or anytime soon.

Boarding and crew were fantastic, but I paid for a window seat with no window. Seat 11D on a CRJ-900 apparently does not have a window. Lesson learned.

Terrible. Four hour delay because Delta could not find crew to man the aircraft. Terrible communication. Terrible insight into the delays. One of the worst flight experiences I’ve had.

It was good. The leg room was not great in Row 1.

Everything was great except for the boarding process. Everyone is lining up all at the same time and it’s hard to tell between the groups as they are way too large.

Women boarding passengers at the gate was absolutely rude and disrespectful of passengers. The flight attendant was absolutely delightful! Smiling and connected with the passengers. So happy. The seats are cramped and uncomfortable but I guess that’s just the way it is Communication regarding flight was excellent

Overall we had a good experience during our flight from San Francisco to Houston.

Airport terminal was outdated, flight was on a small jet with no wifi

We were delayed for about an hour from taking off due to traffic control procedures at the destination airport. But once in the air, the flight went well. The crew members were great and provided cabin service despite moderate turbulence during much of the flight.

it was a very short flight so my expectations were low.

As great a red-eye flight as red-eye flights can be.

Once boarding started it was pretty quick. Food was inedible; cold and salty..

Entertainment kept turning itself off. Gave up on watching a movie.

Both the WIFI and entertainment did not work for 2.5h

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

Both flights were significantly delayed. The flight experience itself was great.

My flight got delayed and eventually canceled, then rescheduled. I and several others had a connection from Boston to Paris and asked several times if we would make it. They assured us we would and then rebooked us mid flight without our consent and closed doors early even though they said they communicated we were a bit delayed. We got stranded in Boston and I opted with being rebooked for a different connection to France since they refused to pay for a Hotel. I've now been in Europe for 5 days and still haven't recieved my bags. There was absolutely no urgency for the fact that I'm in a foreign country with absolutely no change of clothes or any of my medication. Such an overwhelming and frustrating experience.

Automated scanning was slow and somewhat haphazard. Too many people were unfamiliar with the tech and were forced to learn on the fly. The hands off approach of the gate staff made it more uncomfortable. This needs work. Overall the flight and cabin crew were excellent.

The crew for the flight was A+ top notch. They were friendly and professional and made the flight a very relaxing and enjoable.

Rude crew member. She seemed annoyed at me without me saying a single word. Also loudly admonished me for having my bag next to my seat instead of tucked away before landing. Just telling me to put it away and guiding me without giving me a lecture would have been enough.

No included food for a 5 hour flight and the entertainment was only accessible if you had wired headphones (not provided). Otherwise though, great and smooth flying and customer service.

Crew were fantastic and so catering and wonderful! Full score for the entire crew!

Because of weather and mechanical issues our flight was 4 hours late. The only compensation offered to us was a meal voucher to be used only at Boston Airport and only on the day issued. But by the time it was offered to us all the restaurants were closed, so there was no way to use that offer.

Friendly crew, efficient boarding and flight arrived early. Couldn’t ask for a better experience

Terrible. They canceled our early morning flight after midnight on the day of and had no available flights to rebook my family on for the next 72 hours. Yet they still had other flights that were not cancelled from JFK so it couldn’t be based on the weather. It felt like they canceled the flight based on it not being profitable enough for them. I am not interested in traveling with the again. The absolute worse customer service and lack of accountability.

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

Information on your arrival and departure airports