How long is the flight from Region of Siem Reap to London Heathrow Airport?

Emirates, Etihad Airways, and Vietnam Airlines can get you from Region of Siem Reap to London Heathrow Airport in just under 28h 50m. Your travel time can differ by up to 2h 25m. The distance from Region of Siem Reap to London Heathrow Airport is about 6106 mi. Both multi-stop and direct flights can be found to your destination and back.

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 SI to LHR?

Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Region of Siem Reap to London Heathrow Airport as you normally would.

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

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

How can I find direct flights from Siem Reap to Heathrow?

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

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

Yes. Cheapflights offers flight deals from Siem Reap 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.

£240+ Cheap Flights from Siem Reap to London Heathrow Airport

Cheap flight deals from Siem Reap to Heathrow

Enter your travel dates to find the best prices.

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Cheapest flights from Siem Reap to Heathrow
Explore the most affordable flight options available from Siem Reap to Heathrow. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 6 November 2026.

Mon 16/1117:40 -

3 stops31h 30m

Fri 20/1112:30 -

2 stops22h 35m

Deal found 3/11£660

Sat 26/1221:05 -

2 stops51h 25m

Sun 17/121:00 -

2 stops40h 05m

Deal found 5/11£704

Thu 12/1118:40 -

2 stops29h 50m

Mon 14/1206:00 -

3 stops25h 50m

Deal found 1/11£768

Sat 26/1220:30 -

1 stop17h 45m

Sun 17/121:00 -

2 stops35h 50m

Deal found 5/11£789

Wed 4/1109:55 -

2 stops39h 30m

Tue 17/1120:05 -

2 stops29h 40m

Deal found 2/11£838

Wed 4/1119:25 -

2 stops29h 35m

Tue 17/1120:55 -

2 stops29h 20m

Deal found 4/11£843

Mon 30/1117:55 -

2 stops31h 15m

Wed 30/1213:55 -

2 stops36h 20m

Deal found 4/11£876

Thu 12/1123:50 -

2 stops21h 00m

Mon 14/1215:50 -

2 stops22h 20m

Deal found 1/11£879

Wed 4/1118:40 -

1 stop19h 35m

Tue 17/1111:00 -

1 stop26h 30m

Deal found 2/11£914

Find flight deals from Siem Reap to Heathrow

Round-trip from	£660
One-way from	£240

16/11-20/11
5 total stops
54h 05m total
Siem Reap to London

Search Deals

17/12-31/12
2 total stops
31h 05m total
Siem Reap to London

Search Deals

Cheapflights Fare Finder

Use the filters below to find and compare flights from Siem Reap to London Heathrow Airport that are best for you.

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Route

Depart

Return

Price

Cheapest return flight

Siem ReapLondon

SAI Siem Reap–Angkor Intl - LHR London Heathrow

SAILHR

Siem Reap–Angkor Intl

Thu 17/12

19:05-19:10

2 stops31h 05m

London Heathrow

Wed 31/12

00:00-06:00

Nonstop0h 00m

£240

Siem ReapLondon

SAI Siem Reap–Angkor Intl - LHR London Heathrow

SAILHR

Siem Reap–Angkor Intl

Sun 21/2

19:05-06:25

2 stops42h 20m

London Heathrow

Wed 31/12

00:00-06:00

Nonstop0h 00m

£261

Siem ReapLondon

SAI Siem Reap–Angkor Intl - LHR London Heathrow

SAILHR

Siem Reap–Angkor Intl

Mon 18/1

19:05-17:30

2 stops29h 25m

London Heathrow

Wed 31/12

00:00-06:00

Nonstop0h 00m

£273

Siem ReapLondon

SAI Siem Reap–Angkor Intl - LHR London Heathrow

SAILHR

Siem Reap–Angkor Intl

Wed 16/12

17:55-20:30

2 stops33h 35m

London Heathrow

Wed 31/12

00:00-06:00

Nonstop0h 00m

£289

Fastest return journey

Siem ReapLondon

SAI Siem Reap–Angkor Intl - LHR London Heathrow

SAILHR

Siem Reap–Angkor Intl

Wed 16/12

21:30-07:15

1 stop16h 45m

London Heathrow

Wed 31/12

00:00-06:00

Nonstop0h 00m

£306

Siem ReapLondon

SAI Siem Reap–Angkor Intl - LHR London Heathrow

SAILHR

Siem Reap–Angkor Intl

Thu 17/12

17:55-07:15

1 stop20h 20m

London Heathrow

Wed 31/12

00:00-06:00

Nonstop0h 00m

£306

Siem ReapLondon

SAI Siem Reap–Angkor Intl - LHR London Heathrow

SAILHR

Siem Reap–Angkor Intl

Sun 21/2

21:05-06:25

3 stops40h 20m

London Heathrow

Wed 31/12

00:00-06:00

Nonstop0h 00m

£317

Siem ReapLondon

SAI Siem Reap–Angkor Intl - LHR London Heathrow

SAILHR

Siem Reap–Angkor Intl

Sun 15/11

21:05-17:30

3 stops51h 25m

London Heathrow

Wed 31/12

00:00-06:00

Nonstop0h 00m

£324

Siem ReapLondon

SAI Siem Reap–Angkor Intl - LHR London Heathrow

SAILHR

Siem Reap–Angkor Intl

Tue 26/1

17:40-18:25

3 stops31h 45m

London Heathrow

Wed 31/12

00:00-06:00

Nonstop0h 00m

£344

Siem ReapLondon

SAI Siem Reap–Angkor Intl - LHR London Heathrow

SAILHR

Siem Reap–Angkor Intl

Thu 28/1

17:55-07:15

1 stop20h 20m

London Heathrow

Wed 31/12

00:00-06:00

Nonstop0h 00m

£455

Flights are sorted by cheapest return flights first.

Deals found on 4/11

Showing 1-10 of 22 resultsSorted by cheapest first

Best time to book a flight from Siem Reap to Heathrow

Have a flexible travel schedule? Discover the best time to fly to Heathrow from Siem Reap with our price prediction graph.

SAI-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.

Cheapflights Insights

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

KHSI-LHR

SAI-LHR

No data available for this route at this time. Please check back soon.

Related info for your journey

How long is the flight from Region of Siem Reap to London Heathrow Airport?
Emirates, Etihad Airways, and Vietnam Airlines can get you from Region of Siem Reap to London Heathrow Airport in just under 28h 50m. Your travel time can differ by up to 2h 25m. The distance from Region of Siem Reap to London Heathrow Airport is about 6106 mi. Both multi-stop and direct flights can be found to your destination and back.
Can I find deals for flights from Siem Reap to Heathrow that include hotel bookings?
Yes. In addition to deals on Siem Reap to Heathrow flights, Cheapflights offers holiday packages that include both flights and hotel.
How can I find direct flights from Siem Reap to Heathrow?
After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Siem Reap to Heathrow.
Can I find deals for business class flights from Siem Reap to Heathrow?
Yes. Cheapflights offers flight deals from Siem Reap 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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Cheapflights makes it easy to find Siem Reap to Heathrow flights by helping our users search from 900+ travel sites for deals. We also provide you with filters for cabin, price, airline, airports, number of stops, and many more to narrow down that perfect flight.

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

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

Cheapflights does show flights with no change fees to all users. To see these options for flights from Siem Reap to Heathrow, users can toggle the no change fees filter when performing a flight search.

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

Yes, Cheapflights offers price alerts on Siem Reap to Heathrow flights so you can book your travel at the perfect time. Price Alerts can be enabled by clicking the bell icon next to the flight deals above and providing your email address where you want to receive the alerts.

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Cheap flights from Siem Reap to London Heathrow Airport from £240

This is the cheapest retur flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 17/12. Fares are subject to change and may not be available on all flights or dates of travel.

Cheap flight deals from Siem Reap to Heathrow

Cheapest flights from Siem Reap to HeathrowExplore the most affordable flight options available from Siem Reap to Heathrow. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 6 November 2026.

Explore the most affordable flight options available from Siem Reap to Heathrow. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 6 November 2026.

Best flights from Siem Reap to HeathrowDiscover carefully curated flight deals from Siem Reap to Heathrow that have cost, travel time, and stopovers in mind to ensure you get the best travel experience. Data last updated 6 November 2026.

Discover carefully curated flight deals from Siem Reap to Heathrow that have cost, travel time, and stopovers in mind to ensure you get the best travel experience. Data last updated 6 November 2026.

Last-minute flights from Siem Reap to HeathrowDiscover last-minute flight deals from Siem Reap to Heathrow. Data last updated 6 November 2026 and is based on user searches.

Discover last-minute flight deals from Siem Reap to Heathrow. Data last updated 6 November 2026 and is based on user searches.

One-way flights from Siem Reap to HeathrowSearch for one-way flight options from Siem Reap to Heathrow. Find affordable one-way fares based on user searches. Data last updated 6 November 2026.

Search for one-way flight options from Siem Reap to Heathrow. Find affordable one-way fares based on user searches. Data last updated 6 November 2026.

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Use the filters below to find and compare flights from Siem Reap to London Heathrow Airport that are best for you.

Best time to book a flight from Siem Reap to Heathrow

Have a flexible travel schedule? Discover the best time to fly to Heathrow from Siem Reap with our price prediction graph.

Cheapflights Insights

Related info for your journey

How long is the flight from Region of Siem Reap to London Heathrow Airport?

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

How can I find direct flights from Siem Reap to Heathrow?

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

Travelling to a place near London Heathrow Airport?

Browse thousands of different options on Cheapflights for your next trip

Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.

Alternative routes for Siem Reap to Heathrow

See prices for flight routes from nearby airports that may be better suited for you.

Complete your trip

Complete your trip to Heathrow by adding a car hire and/or hotel booking to your travel itinerary.

Direct flights to England

Book a non-stop flight to one of these other cities located in England.

Search flights from Siem Reap to Heathrow by cabin class

Find flights from Siem Reap to Heathrow, based on your preferred cabin class, be it economy, premium economy, business, or first class.

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 6 November 2026.

Siem Reap and Heathrow flights

Browse other Siem Reap and Heathrow flight options. Last updated on 6 November 2026.

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

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

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Cheapest flights from Siem Reap to Heathrow
Explore the most affordable flight options available from Siem Reap to Heathrow. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 6 November 2026.

Best flights from Siem Reap to Heathrow
Discover carefully curated flight deals from Siem Reap to Heathrow that have cost, travel time, and stopovers in mind to ensure you get the best travel experience. Data last updated 6 November 2026.

Last-minute flights from Siem Reap to Heathrow
Discover last-minute flight deals from Siem Reap to Heathrow. Data last updated 6 November 2026 and is based on user searches.

One-way flights from Siem Reap to Heathrow
Search for one-way flight options from Siem Reap to Heathrow. Find affordable one-way fares based on user searches. Data last updated 6 November 2026.