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Cheap flights from Portland, Maine to London Heathrow Airport from £264

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 28/8. Fares are subject to change and may not be available on all flights or dates of travel.
PWM — LHR
1 Sep — 8 Sep1
1 adult
1 adult, Economy, 0 bags

Cheap flight deals from Portland to Heathrow

Enter your travel dates to find the best prices.

Cheapest flights from Portland to Heathrow
Explore the most affordable flight options available from Portland to Heathrow. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 2 August 2026.

Mon 9/1108:45
PWM
-
LHR
1 stop18h 40m
United Airlines
Wed 11/1106:50
LHR
-
PWM
2 stops21h 31m
United Airlines
Deal found 28/7£547
Sun 6/906:00
PWM
-
LHR
1 stop9h 45m
JetBlue
Tue 8/908:15
LHR
-
PWM
1 stop20h 55m
JetBlue
Deal found 29/7£586
Fri 11/916:20
PWM
-
LHR
1 stop11h 30m
Multiple Airlines
Fri 18/911:55
LHR
-
PWM
1 stop16h 59m
Multiple Airlines
Deal found 28/7£617
Fri 25/906:00
PWM
-
LHR
1 stop9h 45m
JetBlue
Mon 28/908:15
LHR
-
PWM
1 stop20h 39m
JetBlue
Deal found 29/7£621
Sat 5/906:40
PWM
-
LHR
1 stop9h 05m
JetBlue
Sat 12/908:15
LHR
-
PWM
1 stop20h 39m
JetBlue
Deal found 28/7£624
Tue 10/1114:05
PWM
-
LHR
1 stop11h 35m
United Airlines
Tue 24/1106:50
LHR
-
PWM
2 stops17h 12m
United Airlines
Deal found 29/7£640
Tue 10/1116:03
PWM
-
LHR
1 stop13h 27m
Delta
Tue 17/1110:00
LHR
-
PWM
2 stops18h 55m
Delta
Deal found 28/7£641
Tue 10/1116:03
PWM
-
LHR
1 stop13h 27m
Delta
Tue 24/1110:00
LHR
-
PWM
2 stops18h 55m
Delta
Deal found 1/8£641
Sat 7/1108:45
PWM
-
LHR
2 stops41h 25m
Air Canada
Fri 20/1113:00
LHR
-
PWM
2 stops39h 21m
Air Canada
Deal found 1/8£650

Find flight deals from Portland to Heathrow

Discover tips and strategies to find the most affordable flight options for your journey from Portland (PWM) to Heathrow (LHR). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated 2 August 2026.

Round-trip from

£547

One-way from

£264

Popular in

June

Cheapest in

February

Average price

£897
United Airlines
  • United Airlines
  • 9/11-11/11
  • 3 total stops
  • 40h 11m total
  • Portland to London
Search Deals
JetBlue
  • JetBlue
  • 28/8
  • 1 total stop
  • 9h 45m total
  • Portland to London
Search Deals
Highest demand for flights based on searches. 20% potential increase in price (£161 potential increase over avg. return price).
Search Deals
Cheapest flight prices on average. 10% potential price decrease (£61 potential savings vs. average return price).
Search Deals
Average for round-trip flights in August 2026
Search Deals

Cheapflights Fare Finder

 
Customise your flight search to find flights from Portland to Heathrow that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 858,174 searches. Data last updated 2 August 2026.
Use the filters below to find and compare flights from Portland to London Heathrow Airport that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest return flight

PortlandLondon

PWM - LHR

PWMLHR

Portland

Mon 9/11

08:45-08:25

1 stop18h 40m

London Heathrow

Wed 11/11

06:50-23:21

2 stops21h 31m

£547

PortlandLondon

PWM - LHR

PWMLHR

Portland

Tue 10/11

15:10-11:05

1 stop14h 55m

London Heathrow

Tue 17/11

06:50-18:52

2 stops17h 02m

£640
Fastest return journey

PortlandLondon

PWM - LHR

PWMLHR

Portland

Tue 10/11

14:05-06:40

1 stop11h 35m

London Heathrow

Tue 24/11

06:50-19:02

2 stops17h 12m

£640

PortlandLondon

PWM - LHR

PWMLHR

Portland

Sat 7/11

15:10-21:20

1 stop25h 10m

London Heathrow

Fri 20/11

06:50-09:00

2 stops31h 10m

£641

PortlandLondon

PWM - LHR

PWMLHR

Portland

Tue 10/11

16:03-13:45

2 stops16h 42m

London Heathrow

Tue 24/11

06:30-23:55

2 stops22h 25m

£644

PortlandLondon

PWM - LHR

PWMLHR

Portland

Tue 10/11

06:00-07:45

2 stops20h 45m

London Heathrow

Tue 17/11

06:30-23:33

2 stops22h 03m

£644
Cheapest one-way
Fastest single journey

PortlandLondon

PWM - LHR

PWMLHR

Portland

Sun 30/8

06:00-20:45

1 stop9h 45m

£291

PortlandLondon

PWM - LHR

PWMLHR

Portland

Sat 10/10

16:47-13:15

2 stops15h 28m

£318

PortlandLondon

PWM - LHR

PWMLHR

Portland

Sat 10/10

14:32-21:00

3 stops25h 28m

£346

PortlandLondon

PWM - LHR

PWMLHR

Portland

Fri 28/8

07:40-05:55

2 stops17h 15m

£388

Flights are sorted by cheapest return flights first.

Deals found on 28/7

Sorted by cheapest first

Best time to book a flight from Portland to Heathrow

Have a flexible travel schedule? Discover the best time to fly to Heathrow from Portland with our price prediction graph.
Estimated return price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Cheapflights Insights

Everything you need to know about your flight from Portland to London Heathrow Airport

What’s the top stopover airport for flights from Portland, Maine to London Heathrow Airport?

Share of one-stop return flights from Portland, Maine to London Heathrow Airport chosen by Cheapflights users in the past 12 months, using the same stopover each way.

Newark (EWR) – chosen by Cheapflights users on 50% of one-stop itineraries from Portland, Maine to London Heathrow Airport on Cheapflights.

What’s the cheapest stopover airport for flights from Portland, Maine to London Heathrow Airport?

Average return fare for one-stop flights from Portland, Maine to London Heathrow Airport, chosen by Cheapflights users in the past 12 months, with the same stopover each way.

New York (JFK) is the most affordable one-stop option, with an average return flight price of £427.

What’s the fastest stopover option from Portland, Maine to London Heathrow Airport?

Shortest average travel time for one-stop one-way flights from Portland, Maine to London Heathrow Airport, based on itineraries clicked by Cheapflights users over the past 12 months, grouped by stopover airport.

Flights via Newark (EWR) have the shortest average one-way travel time for one-stop routes: 9h 40m.

Which airport typically offers the quickest stopover for flights from Portland, Maine to London Heathrow Airport?

Average stopover duration for one-stop one-way flights from Portland, Maine to London Heathrow Airport, chosen by Cheapflights users in the last 12 months, grouped by stopover airport.

Flights via Newark (EWR) offer the fastest connection on this route, with an average stopover time of 1h 24m.

Related info for your journey

Find useful and relevant information for your journey from Portland to Heathrow. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • What airport do you fly from for flights from Portland to London Heathrow?

    For a flight from Portland to London Heathrow, you will be flying from Portland. Portland (PWM) is just 2.9 mi from the center of the city. Portland is the only Portland airport and it handles 0 outbound flights to London Heathrow per day. 0 airlines have flights to London Heathrow from Portland on a regular basis.

  • How long is the flight from Portland, Maine to London Heathrow Airport?

    For as low as £547, United Airlines can have you in London Heathrow Airport from Portland, Maine in 18h 40m. The distance from Portland, Maine to London Heathrow Airport is about 3173 mi.

  • Can I find deals for flights from Portland to Heathrow that include hotel bookings?

    Yes. In addition to deals on Portland to Heathrow flights, Cheapflights offers holiday packages that include both flights and hotel.

  • How can I find direct flights from Portland to Heathrow?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Portland to Heathrow.

  • Can I find deals for business class flights from Portland to Heathrow?

    Yes. Cheapflights offers flight deals from Portland to Heathrow by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

See more FAQs

Travelling to a place near London Heathrow Airport?

Book flights to London Heathrow Airport if you plan to visit one of these locations
Hounslow
Milton Keynes
Luton
Gatwick
Wembley
Slough
Ilford
Hayes
Croydon
Colchester
Brentford
Eastbourne
Northampton
Watford
Swindon
Southend-on-Sea
Enfield
Kingston upon Thames
Poole
Southall

Browse thousands of different options on Cheapflights for your next trip

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Alternative routes for Portland to Heathrow

See prices for flight routes from nearby airports that may be better suited for you.
Boston to Heathrow flights
Boston to Gatwick flights
Boston to London City flights
Boston to Stansted flights
Boston to Luton flights
Bangor to Heathrow flights
Boston to Southend flights

Fly with Cheapflights

Find the best flight deals on Cheapflights, where travellers can enjoy low prices and a wide availability of flights to their desired destinations.

How does Cheapflights help users find flights from Portland to Heathrow?

Deals for Portland to Heathrow flights are sourced from 900+ travel sites when you use Cheapflights. When all flight results come back, Cheapflights lets you sort and filter flights using different criteria to choose better, like price, airport, cabin class, and plenty of other options.

Why should you use Cheapflights to find cheap flight tickets from Portland to Heathrow?

It’s simple! Cheapflights, which is free to use for everyone, saves millions of users time and money every year by helping them find the cheapest and most suitable flights from Portland to Heathrow.

Can Cheapflights find flights from Portland to Heathrow with no change fees?

Yes! Cheapflights helps users easily find flights from Portland to Heathrow with no change fees.

Can Cheapflights notify me if prices for flights from Portland to Heathrow become cheaper?

Yes, and it’s super simple to set up. Click the bell icon next to the flight deals above and provide a valid email address to enable Price Alerts. That’s it!

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