PWM - LON

$324 Find Cheap Flights from Portland to London - Compare and Save

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 7/15. 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

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Everything you should know

Cheapest round-trip
$738
United Airlines
Sun 11/15Tue 11/17
PWM - LHR • 1 stop
Cheapest one-way
$324
Multiple Airlines
Wed 7/15
PWM - LGW • 2 stops
Top airlines
Cheapest • from $738 (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 $853 (round-trip)
Shortest trip • 9h 59m (one-way)
Insights
Insights
Insights
Insights
When to travel
Cheapest • 100% price drop
Most popular
Good to know
Good to know
+1
+1
Good to know
Good to know
+1
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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

Sun, Nov 15 - Tue, Nov 17
United Airlines Logo
3:43 pm - 8:25 am
PWM
-
LHR
11h 42m
1 stop
United Airlines Logo
6:50 am - 4:09 pm
LHR
-
PWM
14h 19m
2 stops
$738United Airlines
Sun, Nov 15 - Tue, Nov 17
United Airlines Logo
2:23 pm - 9:10 am
PWM
-
LHR
13h 47m
2 stops
United Airlines Logo
6:50 am - 6:21 pm
LHR
-
PWM
16h 31m
2 stops
$742United Airlines
Sun, Aug 23 - Thu, Aug 27
JetBlue Logo
6:00 am - 8:45 pm
PWM
-
LHR
9h 45m
1 stop
JetBlue Logo
8:15 am - 12:25 am
LHR
-
PWM
21h 10m
1 stop
$822JetBlue
Tue, Aug 25 - Mon, Aug 31
JetBlue Logo
1:25 pm - 9:30 am
PWM
-
LHR
15h 05m
1 stop
JetBlue Logo
8:15 am - 12:30 pm
LHR
-
PWM
33h 15m
1 stop
$826JetBlue
Tue, Oct 13 - Tue, Nov 3
JetBlue Logo
6:00 am - 8:45 pm
PWM
-
LHR
9h 45m
1 stop
JetBlue Logo
12:20 pm - 11:43 pm
LHR
-
PWM
16h 23m
1 stop
$827JetBlue
Sun, Nov 1 - Sun, Nov 8
Multiple Airlines Logo
6:00 am - 6:30 am
PWM
-
LHR
19h 30m
2 stops
Multiple Airlines Logo
8:15 am - 11:43 pm
LHR
-
PWM
20h 28m
1 stop
$845Multiple Airlines
Sat, Nov 7 - Sun, Nov 15
Multiple Airlines Logo
5:09 pm - 8:15 am
PWM
-
LGW
34h 06m
2 stops
Multiple Airlines Logo
12:35 pm - 9:08 am
LGW
-
PWM
25h 33m
1 stop
$851Multiple Airlines
Sat, Sep 12 - Sat, Sep 19
Scandinavian Airlines Logo
6:02 am - 9:35 am
PWM
-
LHR
22h 33m
2 stops
Scandinavian Airlines Logo
6:40 am - 11:56 pm
LHR
-
PWM
22h 16m
2 stops
$856Scandinavian Airlines
Sun, Nov 1 - Sun, Nov 8
Delta Logo
12:52 pm - 7:15 am
PWM
-
LCY
13h 23m
2 stops
Delta Logo
1:45 pm - 11:49 pm
LCY
-
PWM
15h 04m
2 stops
$954Delta
Wed, Aug 19 - Mon, Aug 24
Delta Logo
12:47 pm - 9:30 am
PWM
-
LCY
15h 43m
2 stops
Delta Logo
10:00 am - 11:13 pm
LCY
-
PWM
18h 13m
2 stops
$1,852Delta
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.

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 January, where tickets cost $0 (return) on average. On the other hand, the most expensive months are July and June, where the average cost of round-trip tickets is $1,294 and $986 respectively.

Good to know

Low seasonDecember
Cheapest flight$324
Best time to beat the crowds with an average 19% drop in price.
Most popular time to fly and prices are also 19% lower on average.
Flight from Portland to London Gatwick 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 5 days, the lowest price for a flight from Portland to London was $324 for a one-way ticket and $738 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.

  • 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 airline 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 9927 reviews
7.1Entertainment
7.7Boarding
8.1Crew
6.7Food
7.3Comfort
Airline reviews

I was very disappointed with my experience at the United Airlines baggage check. The representative was rude and unhelpful. I was required to remove approximately 1.5 pounds from my two checked bags, even though it was a very small amount over the limit. The interaction was unnecessarily unpleasant, and I expected much better customer service. I hope United will review this incident and provide additional customer service training to its staff.

10.0 ExcellentAnonymous, Jun 2026
LAX - LHR
Read more United Airlines reviews

I was very disappointed with my experience at the United Airlines baggage check. The representative was rude and unhelpful. I was required to remove approximately 1.5 pounds from my two checked bags, even though it was a very small amount over the limit. The interaction was unnecessarily unpleasant, and I expected much better customer service. I hope United will review this incident and provide additional customer service training to its staff.

Cree was organized and pleasant. Plane had good seating but as it’s a shuttle toilets hadn’t been thoroughly cleaned (eg. bins too full)

Some flight attendants were great others were cranky. Seats were very tight and sitting on an aisle was very hard as the carts and people walking constantly bumped shoulder and arm.

Although the flight was delayed the crew and the flight itself were very good. Couldn't fault anything and after the disappointment of being abandoned in the US by BA it was a welcome relief to travel with United

Liked fold flat bed. Didn’t like having no window. Didn’t like poor choice of food and being served dinner very late, hours after take off of a 7:40pm flight. Servers not friendly. Food horrible in business class.

The flight was heavily booked so boarding was a lengthy process. The FA’s were rather abrupt during this process but became more gracious as the flight went on. Breakfast (puffed pastry and chewy sausage) was pretty horrible but there was fruit and yogurt which they didn’t mess up. Overall it was fine.

Fight was delayed an hour due to operational issues ,then further delayed due to ground control for a total of about 1.30 hours. Salad was completely frozen and flatware was so cold you could barely handle it. Crew was friendly and professional and the flight was smooth. The aircraft was clean and well-serviced.

Waited for our plane from HNL so we didn't miss connection. AMAZING Service for that, then really clean plane. Nice airline attendants.

They changed my flight 5 hours before it took off and changed my connecting airport messing up my entire 1st day in Japan.

Horrible! I paid for a straight flight from Chicago to London. A week before trip it changed and now I had a connecting flight. Our flight was delayed an hour and a half because our flight crew was still flying in from CA. Forty passengers ran from one plane to the next. The next United Airlines flight was delayed two to three hours because of mechanical difficulties. They had to ready another plane which took time. I missed my scheduled excursion in London. 😢

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

Information on your arrival and departure airports