PWM - LON

$256 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 7/5. 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
$632
Typical prices: $860-$1,118
United Airlines
Mon 3/9Mon 3/16
PWM - LHR • 1 stop
Cheapest one-way
$256
United Airlines
Sun 7/5
PWM - LHR • 1 stop
Top airlines
United Airlines
Cheapest • from $632 (round-trip)
Delta
Best reviews • 7.9 score
Airline reviews
Airline reviews
+1
+1
Airline reviews
Airline reviews
+1
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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, Mar 9 - Mon, Mar 16
United Airlines Logo
3:44 pm - 6:20 am
PWM
-
LHR
10h 36m
1 stop
United Airlines Logo
11:10 am - 11:04 pm
LHR
-
PWM
15h 54m
2 stops
$632United Airlines
Mon, Mar 9 - Mon, Mar 16
United Airlines Logo
11:30 am - 6:40 am
PWM
-
LHR
15h 10m
2 stops
United Airlines Logo
6:50 am - 6:25 pm
LHR
-
PWM
15h 35m
2 stops
$636United Airlines
Wed, May 6 - Mon, May 11
United Airlines Logo
3:39 pm - 8:20 am
PWM
-
LHR
11h 41m
1 stop
United Airlines Logo
5:50 pm - 6:23 pm
LHR
-
PWM
29h 33m
2 stops
$661United Airlines
Wed, Apr 15 - Thu, Apr 23
Scandinavian Airlines Logo
2:51 pm - 8:50 am
PWM
-
LHR
12h 59m
1 stop
Scandinavian Airlines Logo
4:20 pm - 12:46 am
LHR
-
PWM
13h 26m
1 stop
$676Scandinavian Airlines
Wed, Mar 25 - Wed, Apr 1
Delta Logo
6:25 am - 8:10 pm
PWM
-
LHR
9h 45m
1 stop
Delta Logo
9:55 am - 11:22 pm
LHR
-
PWM
18h 27m
2 stops
$680Delta
Wed, Apr 15 - Fri, Apr 24
Scandinavian Airlines Logo
4:42 pm - 1:15 pm
PWM
-
LHR
15h 33m
2 stops
Scandinavian Airlines Logo
1:25 pm - 11:23 pm
LHR
-
PWM
14h 58m
1 stop
$681Scandinavian Airlines
Wed, Apr 15 - Wed, Apr 22
Delta Logo
2:51 pm - 6:20 am
PWM
-
LHR
10h 29m
1 stop
Delta Logo
10:45 am - 11:24 pm
LHR
-
PWM
17h 39m
2 stops
$682Delta
Wed, Mar 25 - Wed, Apr 1
KLM Logo
2:30 pm - 1:50 pm
PWM
-
LHR
19h 20m
2 stops
KLM Logo
11:45 am - 11:59 pm
LHR
-
PWM
17h 14m
2 stops
$683KLM
Wed, May 6 - Mon, May 11
Turkish Airlines Logo
6:00 am - 4:40 pm
PWM
-
LGW
29h 40m
2 stops
Turkish Airlines Logo
10:50 am - 11:36 pm
LGW
-
PWM
41h 46m
2 stops
$940Turkish Airlines
Wed, May 6 - Mon, May 11
Turkish Airlines Logo
6:00 am - 4:40 pm
PWM
-
LGW
29h 40m
2 stops
Turkish Airlines Logo
5:35 pm - 11:36 pm
LGW
-
PWM
35h 01m
2 stops
$1,095Turkish Airlines
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.

Which airlines provide the cheapest flights from Portland to London?

The cheapest round-trip price for the route for each airline clicked by KAYAK users in the last 72 hours.

In the past 3 days, the cheapest round-trip tickets from Portland to London were found on United Airlines ($632) and Scandinavian Airlines ($676).

Good to know

Low seasonOctober
Cheapest flight$256
Best time to beat the crowds with an average 29% 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 $256 for a one-way ticket and $632 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 $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 $753 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 8180 reviews
8.5Crew
8.1Boarding
7.8Entertainment
7.2Food
7.9Comfort
Airline reviews

Was forced to check in my small carry on, even though I informed the crew it has very fragile items inside

2.0 MediocreJaspreet, Feb 2026
SEA - SMF
Read more Delta reviews

Was forced to check in my small carry on, even though I informed the crew it has very fragile items inside

This was one of the worst flights I’ve been on in years. I upgraded to comfort and had such an uncomfortable experience. The person next to me was oversized - which I understand - however, they took up their space and mine. I could only use about 50% of my seat space to not be physically touching this person the entire flight and there was no spatial awareness. I also could not use the seat outlet because their body was obstructing it. It was very inconvenient. Their body kept touching me repeatedly during the flight and I felt very uncomfortable. To pay more for an upgraded space and then not even being able to use it was highly disappointing.

No wheel chair as requested at Atlanta arrival on first flight.

Only freetext wifi was available in flight; browsing WiFi required payment. Since the seats had no in flight entertainment, Delta should revisit this policy on this longer flight.

Only water, tea or coffee served midflight, even to comfort seating. Man next to me needed two seats and took up a portion of my seat and Delta did nothing.

The flight was great as well as the airline staff

First class and monitors weren’t working for mine & my husbands. Eventually fixed, but quite annoyed as we bought first class. Also, No foot rests.

Prior to takeoff, the pilot told us there was a possibility of not being able to land and going to Portland. Well that happened, we took off and then did 8 loops around Spokane before the pilot told us we ran out of fuel and had to go to Portland. So for a 35 minute flight we have now been on the plane for 3 hours (boarded at 6:50 am and landed in Portland at 10:30). Then, we just sat in Portland's airport with no updates of when we can start heading back. All of a sudden, our pilots and crew just left, leaving us stranded in a different city and state. We continued to sit in Portland until we finally got a new crew assigned and boarded the plane (This was from 10:30-2). We then sat on the plane for an additional hour before take off because they had to count us multiple times. We finally landed in Spokane at 3:55 PM. So a flight that should have taken at max an hour took us 10 hours and we missed the majority of the recruiting event we went for.

It was delayed but other than that it was great.

Got on the plane and sat there for an hour before departure.

Check-in and in-flight staff were better than average. The seat was a fair size but too hard and not enough padding. The cushion/pillow provided is poor (thin and seems to be disposable ,it provides no effective cushioning or support). Food was OK-ish but no choice of inflight snacks and no easy place to get drinks other than water (I could ask for juice by intruding into the staff area at the back of the plane) Entertainment was very good actually. Overall better than I expected from a US-based airline (sorry!) but compared to ANA or Singapore it was so-so. (I live in Japan so they are my comparative airlines)

Everything was on time Will use united again for sure

Plane outlets in my row not working to charge phone. Staff response was, well it should be. Plug into seed for volume not working well. Had to find the sweet spot for plug in or it would shut off and on.

Wifi took a while to kick in and we had a maintenance issue that took over 40 mins at the gate in Washington before pulling back

Fine not above and beyond as I had a connection that was delayed due to maintenance

The power at the seat didn't work and the seat itself was difficult to adjust - this was a business class seat. Flight attendant gave me miles to compensate. The attendant was very professional and on top of his game the entire flight.

Terrible. Our first time back on United for 10 years, the seats in Polaris class are small and uncomfortable. They have squished too many people in to get more $$$. The staff are not friendly and not wanting to accommodate. I asked for two salads rather than a main meal and was advised no we wont do that. Then asked what I would like for breakfast and given something else anyway. I will not be flying United International anytime soon.

Same thing as flight from Pheonix to Newark. Uograded and Promised extra leg room and when I got to the seat it had none.

I upgraded my seat and was promised it would be next to the emergency door for extra leg room and they said it was premium plus but it was at the back of the plane...same thing happened from Newark to Dubai

Everything except the food and entertainment. It was a great experience though

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

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.

Horribly rude check in at airport, worst in 25 years of flying. All over a simple issue they could have googled to resolve.

First time flying with JetBlue and never again. I went to the counter to request meet and assist because I'm 74 and my wife is 79. I walk with a cane and my wife is handicapped and has her own wheel chair. I told the agent that my wife and luggage was at the entrance door. The ticketing agent said to me that they don't offer meet and assist. I need to bring them our luggage and then go back and get my wife in order to get my boarding pass. As I went back to get my luggage a Southwest agent along with a TSA agent recognized the situation and came over and took my wife and luggage to the JetBlue ticketing counter alongside the line and told the JetBlue agent to issue to take our luggage as soon as they could.

Flight was fine, price was good but food onboard was abysmal. I was on there for breakfast and lunch and dinner 845am EST to 845pm GMT and all I got was a yoghurt parfait, fruit and a piece of cake. Later snacks included an ice-cream brownie and a pizza twist. I was hungry by the time I landed and the airport amenities were closed. Not happy.

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

Information on your arrival and departure airports