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Cheap flights from Portland, Maine to London Heathrow Airport from £244

PWM — LHR
29 Sep — 6 Oct1
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

Tue 10/1114:05 -
1 stop11h 35m
Tue 24/1106:50 -
2 stops17h 12m
Deal found 30/8£640
Tue 10/1114:05 -
2 stops14h 05m
Tue 17/1106:50 -
2 stops17h 02m
Deal found 28/8£644
Wed 14/1011:35 -
2 stops14h 20m
Fri 6/1112:05 -
2 stops16h 16m
Deal found 26/8£645
Fri 9/1006:00 -
1 stop9h 45m
Mon 12/1008:15 -
1 stop20h 39m
Deal found 28/8£646
Tue 13/1015:41 -
2 stops13h 34m
Tue 20/1013:50 -
2 stops14h 38m
Deal found 29/8£647
Tue 10/1105:50 -
2 stops20h 20m
Tue 24/1109:00 -
2 stops43h 21m
Deal found 27/8£649
Mon 21/906:00 -
1 stop9h 45m
Sun 4/1011:55 -
1 stop16h 59m
Deal found 26/8£649
Thu 8/1006:00 -
1 stop9h 45m
Mon 12/1008:15 -
1 stop20h 39m
Deal found 28/8£650
Mon 12/1006:00 -
1 stop10h 35m
Mon 19/1017:55 -
2 stops29h 17m
Deal found 28/8£651
Tue 10/1108:49 -
3 stops18h 41m
Tue 17/1106:00 -
3 stops22h 21m
Deal found 30/8£653

Find flight deals from Portland to Heathrow

Round-trip from

£640

One-way from

£244

Popular in

June

Cheapest in

February

Average price

£894
United Airlines
  • United Airlines
  • 10/11-24/11
  • 3 total stops
  • 28h 47m total
  • Portland to London
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Delta
  • Delta
  • 1/12
  • 1 total stop
  • 12h 25m total
  • Portland to London
Search Deals
Highest demand for flights based on searches. 20% potential increase in price (£160 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
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Cheapflights Fare Finder

 
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 Portland - LHR London Heathrow

PWMLHR

Portland

Tue 10/11

15:41-10:25

1 stop13h 44m

London Heathrow

Tue 17/11

06:50-23:21

2 stops21h 31m

£640

PortlandLondon

PWM Portland - LHR London Heathrow

PWMLHR

Portland

Wed 14/10

06:00-20:40

1 stop9h 40m

London Heathrow

Wed 21/10

06:50-19:24

2 stops17h 34m

£640

PortlandLondon

PWM Portland - LHR London Heathrow

PWMLHR

Portland

Tue 20/10

11:35-11:55

1 stop19h 20m

London Heathrow

Wed 28/10

06:50-19:02

2 stops16h 12m

£641

PortlandLondon

PWM Portland - LHR London Heathrow

PWMLHR

Portland

Wed 14/10

16:47-12:05

2 stops14h 18m

London Heathrow

Fri 6/11

08:40-21:00

2 stops17h 20m

£645

PortlandLondon

PWM Portland - LHR London Heathrow

PWMLHR

Portland

Tue 10/11

12:45-09:00

2 stops15h 15m

London Heathrow

Tue 24/11

10:00-23:31

2 stops18h 31m

£645

PortlandLondon

PWM Portland - LHR London Heathrow

PWMLHR

Portland

Tue 20/10

12:42-08:50

2 stops15h 08m

London Heathrow

Wed 28/10

08:40-00:10

2 stops19h 30m

£645
Fastest return journey

PortlandLondon

PWM Portland - LHR London Heathrow

PWMLHR

Portland

Tue 10/11

15:41-08:25

1 stop11h 44m

London Heathrow

Tue 24/11

16:20-23:59

1 stop12h 39m

£663

PortlandLondon

PWM Portland - LHR London Heathrow

PWMLHR

Portland

Mon 16/11

06:30-21:40

1 stop10h 10m

London Heathrow

Wed 18/11

12:20-23:43

1 stop16h 23m

£663

PortlandLondon

PWM Portland - LHR London Heathrow

PWMLHR

Portland

Thu 15/10

17:28-10:20

1 stop11h 52m

London Heathrow

Fri 6/11

10:00-21:00

2 stops16h 00m

£663
Cheapest one-way

PortlandLondon

PWM Portland - LHR London Heathrow

PWMLHR

Portland

Tue 1/12

16:00-09:25

1 stop12h 25m

£244

Flights are sorted by cheapest return flights first.

Deals found on 29/8

Showing 1-10 of 15 resultsSorted by cheapest first
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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

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?

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?

New York (JFK) is the most affordable one-stop option, with an average return flight price of £425.

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

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

Related info for your journey

  • 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 £640, United Airlines can have you in London Heathrow Airport from Portland, Maine in 13h 44m. 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
Northampton
Colchester
Eastbourne
Brentford
Barnet
Salisbury
Southall
Southend-on-Sea
Enfield
Kingston upon Thames
Watford

Browse thousands of different options on Cheapflights for your next trip

Alternative routes for Portland to Heathrow

Boston to Heathrow flights
Boston to London City flights
Boston to Gatwick flights
Boston to Stansted flights
Boston to Luton flights
Bangor to Heathrow flights
Boston to Southend flights

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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.

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

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