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

For as low as £554, United Airlines can have you in London Heathrow Airport from Portland, Maine in 21h 26m. The distance from Portland, Maine to London Heathrow Airport is about 3173 mi.

In terms of precipitation, rainfall in London Heathrow Airport ranges from 40.0 - 70.0 inches per month. January is typically the wettest month, when rainfall can reach 70.0 mm. July is typically the driest time to visit London Heathrow Airport when rainfall is around 40.0 mm.

If weather is an important factor for your trip to London Heathrow Airport, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 17.0 C. Travellers hoping to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 4.0 C).

What is the cheapest time of day to fly from PWM to LHR?

When flying from Portland, Maine to London Heathrow Airport, the time of day you decide to fly out makes little to no difference towards the overall price you’ll pay on tickets.

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.

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.

£242+ Cheap Flights from Portland, Maine to London Heathrow Airport

Cheap flight deals from Portland to Heathrow

Enter your travel dates to find the best prices.

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Best

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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 11 October 2026.

Mon 16/1108:49 -

2 stops21h 26m

Wed 18/1109:00 -

2 stops43h 21m

Deal found 8/10£554

Sun 1/1117:08 -

1 stop33h 47m

Wed 4/1106:50 -

2 stops21h 31m

Deal found 7/10£560

Thu 12/1105:50 -

2 stops44h 20m

Sun 15/1106:50 -

2 stops31h 10m

Deal found 8/10£562

Sat 7/1106:00 -

2 stops19h 30m

Sat 14/1112:05 -

2 stops16h 16m

Deal found 8/10£651

Fri 9/1006:04 -

1 stop19h 41m

Wed 14/1006:30 -

2 stops22h 40m

Deal found 8/10£653

Fri 9/1006:04 -

1 stop20h 11m

Tue 13/1006:30 -

2 stops22h 40m

Deal found 8/10£653

Thu 12/1114:05 -

2 stops14h 05m

Mon 16/1112:05 -

2 stops16h 16m

Deal found 8/10£655

Thu 5/1116:47 -

2 stops15h 58m

Sun 15/1106:30 -

2 stops22h 49m

Deal found 6/10£656

Fri 9/1009:50 -

2 stops18h 10m

Tue 13/1006:50 -

2 stops18h 32m

Deal found 8/10£656

Thu 12/1106:30 -

1 stop10h 10m

Mon 16/1108:05 -

1 stop20h 38m

Deal found 8/10£659

Find flight deals from Portland to Heathrow

Round-trip from	£554
One-way from	£242
Popular in	June
Cheapest in	March
Average price	£900

United Airlines
16/11-18/11
4 total stops
64h 47m total
Portland to London

Search Deals

JetBlue
7/11-31/12
1 total stop
10h 10m total
Portland to London

Search Deals

Highest demand for flights based on searches. 20% potential increase in price (£165 potential increase over avg. return price).

Search Deals

Cheapest flight prices on average. 9% potential price decrease (£57 potential savings vs. average return price).

Search Deals

Average for round-trip flights in October 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

Fastest return journey

PortlandLondon

PWM Portland - LHR London Heathrow

PWMLHR

Portland

Sat 7/11

06:30-21:40

1 stop10h 10m

London Heathrow

Wed 31/12

00:00-18:00

Nonstop0h 00m

£242

PortlandLondon

PWM Portland - LHR London Heathrow

PWMLHR

Portland

Wed 11/11

06:30-21:40

1 stop10h 10m

London Heathrow

Wed 31/12

00:00-18:00

Nonstop0h 00m

£242

PortlandLondon

PWM Portland - LHR London Heathrow

PWMLHR

Portland

Wed 17/2

15:15-10:50

2 stops14h 35m

London Heathrow

Wed 31/12

00:00-18:00

Nonstop0h 00m

£249

PortlandLondon

PWM Portland - LHR London Heathrow

PWMLHR

Portland

Wed 11/11

08:49-05:55

2 stops16h 06m

London Heathrow

Wed 31/12

00:00-18:00

Nonstop0h 00m

£249

PortlandLondon

PWM Portland - LHR London Heathrow

PWMLHR

Portland

Wed 17/2

08:55-08:30

3 stops18h 35m

London Heathrow

Wed 31/12

00:00-18:00

Nonstop0h 00m

£255

PortlandLondon

PWM Portland - LHR London Heathrow

PWMLHR

Portland

Sat 7/11

08:49-06:30

3 stops16h 41m

London Heathrow

Wed 31/12

00:00-18:00

Nonstop0h 00m

£255

PortlandLondon

PWM Portland - LHR London Heathrow

PWMLHR

Portland

Wed 11/11

08:49-07:10

3 stops17h 21m

London Heathrow

Wed 31/12

00:00-18:00

Nonstop0h 00m

£258

PortlandLondon

PWM Portland - LHR London Heathrow

PWMLHR

Portland

Tue 17/11

06:30-21:40

1 stop10h 10m

London Heathrow

Wed 31/12

00:00-18:00

Nonstop0h 00m

£304

PortlandLondon

PWM Portland - LHR London Heathrow

PWMLHR

Portland

Thu 19/11

06:30-21:40

1 stop10h 10m

London Heathrow

Wed 31/12

00:00-18:00

Nonstop0h 00m

£304

PortlandLondon

PWM Portland - LHR London Heathrow

PWMLHR

Portland

Wed 18/11

06:30-21:40

1 stop10h 10m

London Heathrow

Wed 31/12

00:00-18:00

Nonstop0h 00m

£304

Flights are sorted by cheapest return flights first.

Deals found on 7/10

Showing 1-10 of 18 resultsSorted 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.

PWM-LHR

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.

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 £554, United Airlines can have you in London Heathrow Airport from Portland, Maine in 21h 26m. 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.

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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.

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

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Cheap flights from Portland, Maine to London Heathrow Airport from £242

This is the cheapest retur flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 7/11. Fares are subject to change and may not be available on all flights or dates of travel.

Cheap flight deals from Portland to Heathrow

Cheapest flights from Portland to HeathrowExplore 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 11 October 2026.

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 11 October 2026.

Best flights from Portland to HeathrowDiscover carefully curated flight deals from Portland to Heathrow that have cost, travel time, and stopovers in mind to ensure you get the best travel experience. Data last updated 11 October 2026.

Discover carefully curated flight deals from Portland to Heathrow that have cost, travel time, and stopovers in mind to ensure you get the best travel experience. Data last updated 11 October 2026.

Last-minute flights from Portland to HeathrowDiscover last-minute flight deals from Portland to Heathrow. Data last updated 11 October 2026 and is based on user searches.

Discover last-minute flight deals from Portland to Heathrow. Data last updated 11 October 2026 and is based on user searches.

One-way flights from Portland to HeathrowSearch for one-way flight options from Portland to Heathrow. Find affordable one-way fares based on user searches. Data last updated 11 October 2026.

Search for one-way flight options from Portland to Heathrow. Find affordable one-way fares based on user searches. Data last updated 11 October 2026.

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Best time to book a flight from Portland to Heathrow

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Related info for your journey

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

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

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

How can I find direct flights from Portland to Heathrow?

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

Travelling to a place near London Heathrow Airport?

Browse thousands of different options on Cheapflights for your next trip

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Alternative routes for Portland to Heathrow

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Complete your trip

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Direct flights to England

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Search flights from Portland to Heathrow by cabin class

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Other flights to Heathrow

Explore flights to Heathrow departing from other origins. Flights are based on user searches made on Cheapflights and were last updated on 11 October 2026.

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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 11 October 2026.

Best flights from Portland to Heathrow
Discover carefully curated flight deals from Portland to Heathrow that have cost, travel time, and stopovers in mind to ensure you get the best travel experience. Data last updated 11 October 2026.

Last-minute flights from Portland to Heathrow
Discover last-minute flight deals from Portland to Heathrow. Data last updated 11 October 2026 and is based on user searches.

One-way flights from Portland to Heathrow
Search for one-way flight options from Portland to Heathrow. Find affordable one-way fares based on user searches. Data last updated 11 October 2026.