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

A quick flight from London to Region of Siem Reap can take about 16h 20m. Austrian Airlines provides one of the quickest options available for as low as £634. London and Region of Siem Reap are separated by a distance of 6106 mi. When browsing for deals, the options you’ll see will be for both direct flights and flights with stops.

What are the cheapest airlines to fly from London to Region of Siem Reap one-way?

For one-way options, check prices for Austrian Airlines. According to our data, you can fly for as low as £378. Users have also found prices from £451 and £504 on Vietnam Airlines and Singapore Airlines, respectively.

In terms of precipitation, rainfall in Region of Siem Reap ranges from 0.0 - 260.0 inches per month. September is typically the wettest month, when rainfall can reach 260.0 mm. January is typically the driest time to visit Region of Siem Reap when rainfall is around 0.0 mm.

If weather is an important factor for your trip to Region of Siem Reap, use this chart to help with planning. For those seeking warmer temperatures, April is the ideal time of year to visit, when temperatures reach an average of 29.0 C. Travellers hoping to avoid the cold should look outside of December, when temperatures are typically at their lowest (around 24.0 C).

What are the most popular routes from London to Region of Siem Reap?

Most travelers choose London Heathrow - Siem Reap–Angkor Intl, London City - Siem Reap–Angkor Intl or London Gatwick - Siem Reap–Angkor Intl when deciding on the best route from London to Region of Siem Reap.

What are the most popular airlines that fly from London to Region of Siem Reap?

Consider Singapore Airlines, Vietnam Airlines or Thai Airways when booking your flight. These represent the most popular airlines when flying from London to Region of Siem Reap.

What is the cheapest time of day to fly from LON to SI?

When flying from London to Region of Siem Reap, the time of day you decide to fly out makes little to no difference towards the overall price you’ll pay on tickets.

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

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

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

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

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

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

£325+ Cheap Flights from London to Siem Reap

Cheap flight deals from London to Siem Reap

Enter your travel dates to find the best prices.

Cheapest

Best

Last-minute

One-way

Cheapest flights from London to Siem Reap
Explore the most affordable flight options available from London to Siem Reap. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 17 September 2026.

Mon 21/911:15 -

2 stops24h 50m

Tue 29/919:05 -

2 stops41h 55m

Deal found 15/9£489

Wed 16/911:15 -

2 stops23h 55m

Wed 14/1018:05 -

2 stops42h 50m

Deal found 13/9£540

Wed 23/911:00 -

2 stops21h 20m

Wed 21/1019:20 -

2 stops41h 10m

Deal found 14/9£544

Wed 23/912:35 -

2 stops20h 40m

Wed 21/1019:05 -

2 stops30h 15m

Deal found 14/9£620

Thu 3/1206:00 -

2 stops29h 30m

Mon 14/1209:55 -

2 stops18h 45m

Deal found 16/9£628

Tue 10/1107:10 -

3 stops25h 55m

Thu 26/1112:45 -

2 stops24h 45m

Deal found 16/9£631

Mon 21/911:15 -

2 stops24h 50m

Fri 25/919:35 -

2 stops41h 20m

Deal found 15/9£656

Wed 16/922:05 -

2 stops38h 00m

Wed 14/1019:10 -

1 stop27h 45m

Deal found 13/9£669

Mon 21/907:15 -

3 stops27h 55m

Tue 29/923:50 -

3 stops28h 20m

Deal found 15/9£672

Wed 23/922:10 -

2 stops37h 55m

Wed 30/919:10 -

1 stop27h 45m

Deal found 15/9£673

Thu 26/1109:50 -

2 stops25h 15m

Fri 4/1219:05 -

3 stops31h 25m

Deal found 12/9£676

Fri 6/1119:25 -

2 stops16h 05m

Fri 20/1116:50 -

2 stops27h 00m

Deal found 15/9£678

Best flights from London to Siem Reap
Discover carefully curated flight deals from London to Siem Reap that have cost, travel time, and stopovers in mind to ensure you get the best travel experience. Data last updated 17 September 2026.

Sat 23/119:25 -

2 stops16h 20m

Sat 6/209:55 -

2 stops18h 45m

Deal found 16/9£634

Fri 8/110:30 -

3 stops27h 30m

Sat 6/322:00 -

3 stops39h 30m

Deal found 13/9£691

Wed 4/1110:30 -

3 stops26h 10m

Thu 4/210:00 -

2 stops27h 20m

Deal found 15/9£731

Thu 26/1113:30 -

2 stops22h 00m

Fri 4/1216:50 -

2 stops25h 50m

Deal found 12/9£738

Tue 16/221:20 -

1 stop14h 25m

Tue 2/319:25 -

1 stop17h 00m

Deal found 12/9£756

Mon 28/914:55 -

2 stops24h 35m

Sat 24/1023:50 -

2 stops43h 15m

Deal found 17/9£756

Sat 20/213:05 -

1 stop19h 55m

Tue 2/310:45 -

1 stop29h 20m

Deal found 16/9£759

Tue 10/1111:00 -

1 stop26h 30m

Thu 3/1217:05 -

2 stops21h 10m

Deal found 14/9£783

Thu 12/1113:30 -

2 stops43h 30m

Mon 30/1116:50 -

2 stops31h 50m

Deal found 12/9£731

Sun 17/118:40 -

2 stops32h 15m

Sun 24/109:55 -

2 stops28h 55m

Deal found 15/9£744

Thu 3/1221:20 -

1 stop14h 10m

Mon 14/1219:25 -

1 stop17h 00m

Deal found 14/9£782

Thu 3/1211:00 -

1 stop26h 30m

Mon 14/1218:40 -

1 stop19h 35m

Deal found 13/9£785

Wed 30/914:55 -

2 stops24h 35m

Thu 22/1023:50 -

2 stops24h 55m

Deal found 17/9£795

Tue 16/208:45 -

2 stops23h 15m

Tue 2/310:00 -

2 stops27h 30m

Deal found 12/9£789

Mon 12/1008:00 -

2 stops28h 55m

Mon 26/1009:55 -

2 stops29h 45m

Deal found 13/9£791

Thu 3/1209:40 -

2 stops20h 00m

Mon 14/1213:20 -

2 stops29h 20m

Deal found 13/9£814

Tue 10/1111:00 -

1 stop26h 30m

Sat 5/1221:30 -

2 stops40h 45m

Deal found 16/9£831

Thu 31/1207:00 -

2 stops26h 55m

Thu 14/117:05 -

2 stops30h 10m

Deal found 13/9£831

Wed 28/1014:05 -

2 stops24h 05m

Tue 19/123:50 -

2 stops25h 05m

Deal found 17/9£833

Fri 30/1011:00 -

1 stop25h 40m

Wed 13/118:40 -

1 stop19h 35m

Deal found 17/9£837

Tue 12/109:15 -

2 stops26h 30m

Sun 31/109:55 -

2 stops29h 45m

Deal found 14/9£857

Sun 7/208:25 -

3 stops24h 40m

Thu 18/220:45 -

2 stops25h 50m

Deal found 15/9£834

Wed 4/1114:05 -

2 stops24h 05m

Mon 25/113:20 -

2 stops29h 45m

Deal found 17/9£837

Mon 9/1111:00 -

1 stop25h 40m

Sat 23/117:05 -

2 stops21h 10m

Deal found 17/9£845

Wed 30/912:45 -

3 stops26h 45m

Wed 6/119:10 -

3 stops30h 00m

Deal found 14/9£840

Wed 4/1114:05 -

2 stops24h 05m

Thu 4/223:50 -

2 stops25h 05m

Deal found 13/9£846

Thu 29/1011:00 -

1 stop26h 30m

Thu 14/117:55 -

1 stop20h 20m

Deal found 17/9£848

Sat 23/112:20 -

2 stops23h 25m

Fri 5/209:55 -

2 stops32h 45m

Deal found 16/9£986

Wed 21/1006:00 -

3 stops26h 50m

Sat 31/1022:00 -

2 stops47h 00m

Deal found 12/9£854

Sat 23/114:05 -

2 stops39h 35m

Sat 6/223:50 -

2 stops25h 05m

Deal found 16/9£856

Find flight deals from London to Siem Reap

Round-trip from	£628
One-way from	£325
Popular in	December
Cheapest in	July
Average price	£771

SWISS
3/12-14/12
4 total stops
48h 15m total
London to Siem Reap

Search Deals

3/11-31/12
3 total stops
24h 55m total
London to Siem Reap

Search Deals

Highest demand for flights based on searches. 6% potential increase in price (£45 potential increase over avg. return price).

Search Deals

Cheapest flight prices on average. 3% potential price decrease (£22 potential savings vs. average return price).

Search Deals

Average for round-trip flights in September 2026

Search Deals

Fly from

Fly to

Route

Depart

Return

Price

Cheapest return flight

LondonSiem Reap

STN London Stansted - SAI Siem Reap–Angkor Intl

STNSAI

London Stansted

Tue 3/11

07:05-15:00

3 stops24h 55m

Siem Reap–Angkor Intl

Wed 31/12

00:00-18:00

Nonstop0h 00m

£325

LondonSiem Reap

LGW London Gatwick - SAI Siem Reap–Angkor Intl

LGWSAI

London Gatwick

Wed 20/1

11:35-18:05

2 stops23h 30m

Siem Reap–Angkor Intl

Wed 31/12

00:00-18:00

Nonstop0h 00m

£349

LondonSiem Reap

LTN London Luton - SAI Siem Reap–Angkor Intl

LTNSAI

London Luton

Mon 2/11

05:00-15:00

3 stops27h 00m

Siem Reap–Angkor Intl

Wed 31/12

00:00-18:00

Nonstop0h 00m

£367

LondonSiem Reap

LGW London Gatwick - SAI Siem Reap–Angkor Intl

LGWSAI

London Gatwick

Mon 12/10

06:55-14:50

3 stops25h 55m

Siem Reap–Angkor Intl

Wed 31/12

00:00-18:00

Nonstop0h 00m

£367

LondonSiem Reap

LTN London Luton - SAI Siem Reap–Angkor Intl

LTNSAI

London Luton

Sat 31/10

19:45-15:00

3 stops36h 15m

Siem Reap–Angkor Intl

Wed 31/12

00:00-18:00

Nonstop0h 00m

£370

LondonSiem Reap

LGW London Gatwick - SAI Siem Reap–Angkor Intl

LGWSAI

London Gatwick

Thu 15/10

06:40-14:50

3 stops26h 10m

Siem Reap–Angkor Intl

Wed 31/12

00:00-18:00

Nonstop0h 00m

£370

LondonSiem Reap

STN London Stansted - SAI Siem Reap–Angkor Intl

STNSAI

London Stansted

Wed 20/1

14:30-21:45

3 stops24h 15m

Siem Reap–Angkor Intl

Wed 31/12

00:00-18:00

Nonstop0h 00m

£373

LondonSiem Reap

LTN London Luton - SAI Siem Reap–Angkor Intl

LTNSAI

London Luton

Thu 15/10

07:00-14:50

3 stops25h 50m

Siem Reap–Angkor Intl

Wed 31/12

00:00-18:00

Nonstop0h 00m

£376

LondonSiem Reap

LHR London Heathrow - SAI Siem Reap–Angkor Intl

LHRSAI

London Heathrow

Wed 20/1

21:05-11:00

2 stops30h 55m

Siem Reap–Angkor Intl

Wed 31/12

00:00-18:00

Nonstop0h 00m

£382

LondonSiem Reap

LTN London Luton - SAI Siem Reap–Angkor Intl

LTNSAI

London Luton

Mon 9/11

05:00-15:00

3 stops27h 00m

Siem Reap–Angkor Intl

Wed 31/12

00:00-18:00

Nonstop0h 00m

£392

Flights are sorted by cheapest return flights first.

Deals found on 13/9

Showing 1-10 of 60 resultsSorted by cheapest first

...

Best time to book a flight from London to Siem Reap

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

LGW-SAI

LHR-SAI

LTN-SAI

STN-SAI

LCY-SAI

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 London to Siem Reap

LON-KHSI

LGW-SAI

LHR-SAI

LTN-SAI

STN-SAI

What is the cheapest month to book a flight from London to Region of Siem Reap?

Currently, March is the cheapest month in which you can book a flight from London to Region of Siem Reap (average of £743). Flying from London to Region of Siem Reap in December is currently the most expensive (average of £983). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

How much does it cost for a return flight from London to Region of Siem Reap?

Airfare is below average for this route at the moment.

London to Region of Siem Reap flights typically cost between £745 and £843 in December.
The cheapest return price found within the last 5 days was £628 on Multiple Airlines (3 Dec–14 Dec).

Reviews of airlines servicing Siem Reap

Check out reviews from past customers who have flown with Singapore Airlines,Vietnam Airlines, andAustrian Airlines from London to Siem Reap to help guide your decision. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.

Singapore Airlines

8.2

Very Good

1,602 reviews

Check prices

Reviews

1 / 20

10.0

Excellent

Anonymous,Jul 2025

DAD - SIN

Person in front laid back his seat. I’m quite tall found it difficult to sit straight lucky seat next to me was empty was able to stretch my legs. Eating my meal was difficult also as seat remained lowered

Singapore Airlines

8.2

Very Good

1,602 reviews

Singapore Airlines

8.2

Very Good

1,602 reviews

Check prices

Reviews

1 / 20

10.0

Excellent

Anonymous,Jul 2025

DAD - SIN

Vietnam Airlines

7.7

Good

288 reviews

Singapore Airlines

8.2

Very Good

1,602 reviews

Check prices

Reviews

1 / 20

10.0

Excellent

Anonymous,Jul 2025

DAD - SIN

Austrian Airlines

7.5

Good

960 reviews

Singapore Airlines

8.2

Very Good

1,602 reviews

Check prices

Reviews

1 / 20

10.0

Excellent

Anonymous,Jul 2025

DAD - SIN

British Airways

6.7

Okay

8,228 reviews

Singapore Airlines

8.2

Very Good

1,602 reviews

Check prices

Reviews

1 / 20

10.0

Excellent

Anonymous,Jul 2025

DAD - SIN

Related info for your journey

How long is the flight from London to Region of Siem Reap?
A quick flight from London to Region of Siem Reap can take about 16h 20m. Austrian Airlines provides one of the quickest options available for as low as £634. London and Region of Siem Reap are separated by a distance of 6106 mi. When browsing for deals, the options you’ll see will be for both direct flights and flights with stops.
What are the cheapest airlines to fly from London to Region of Siem Reap one-way?
For one-way options, check prices for Austrian Airlines. According to our data, you can fly for as low as £378. Users have also found prices from £451 and £504 on Vietnam Airlines and Singapore Airlines, respectively.
What are the most popular routes from London to Region of Siem Reap?
Most travelers choose London Heathrow - Siem Reap–Angkor Intl, London City - Siem Reap–Angkor Intl or London Gatwick - Siem Reap–Angkor Intl when deciding on the best route from London to Region of Siem Reap.
Can I find deals for flights from London to Siem Reap that include hotel bookings?
Yes. In addition to deals on London to Siem Reap flights, Cheapflights offers holiday packages that include both flights and hotel.
How can I find direct flights from London to Siem Reap?
After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from London to Siem Reap.
Can I find deals for business class flights from London to Siem Reap?
Yes. Cheapflights offers flight deals from London to Siem Reap by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.
What is the cheapest month to book a flight from London to Region of Siem Reap?
Currently, March is the cheapest month in which you can book a flight from London to Region of Siem Reap (average of £743). Flying from London to Region of Siem Reap in December is currently the most expensive (average of £983). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

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Alternative routes for London to Siem Reap

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Birmingham to Siem Reap flights

Manchester to Krong Preah Sihanouk flights

Heathrow to Krong Preah Sihanouk flights

Gatwick to Krong Preah Sihanouk flights

Edinburgh to Siem Reap flights

Top 4 airlines flying from London to Siem Reap

Airline	Cheapest	Average	Flexibility	On-time
Austrian Airlines	Cheapest£539	Average£687	FlexibilityNo cancel fee	On-time78%	Search Austrian Airlines flights
Vietnam Airlines	Cheapest£616	Average£815	FlexibilityNo cancel fee	On-time81%	Search Vietnam Airlines flights
Singapore Airlines	Cheapest£664	Average£931	FlexibilityNo cancel fee	On-time81%	Search Singapore Airlines flights
Thai Airways	Cheapest£908	Average£1,021	FlexibilityNo cancel fee	On-time77%	Search Thai Airways flights

Fly with Cheapflights

How does Cheapflights help users find flights from London to Siem Reap?

Cheapflights goes through 900+ travel sites to look for the best flight deals for flights from London to Siem Reap. Too many options? Cheapflights also provides filters for things like airlines, price ranges, and number of stops to help you make a decision easily.

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

Cheapflights taps into our reliable network of hundreds of airlines and travel agencies to find the best deals for flights from London to Siem Reap for you. Better yet — we are completely free to use.

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

Users can book flights with no change fees policies with our dedicated filters. Book flights from London to Siem Reap flexibly with Cheapflights today.

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

Yes, Cheapflights has a feature called Price Alert, which notifies users when flight prices change. Track prices for your flight to Siem Reap from London today and book when prices fit your budget.

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Cheap flights from London to Siem Reap from £325

This is the cheapest retur flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 3/11. Fares are subject to change and may not be available on all flights or dates of travel.

Cheap flight deals from London to Siem Reap

Cheapest flights from London to Siem ReapExplore the most affordable flight options available from London to Siem Reap. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 17 September 2026.

Explore the most affordable flight options available from London to Siem Reap. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 17 September 2026.

Best flights from London to Siem ReapDiscover carefully curated flight deals from London to Siem Reap that have cost, travel time, and stopovers in mind to ensure you get the best travel experience. Data last updated 17 September 2026.

Discover carefully curated flight deals from London to Siem Reap that have cost, travel time, and stopovers in mind to ensure you get the best travel experience. Data last updated 17 September 2026.

Last-minute flights from London to Siem ReapDiscover last-minute flight deals from London to Siem Reap. Data last updated 17 September 2026 and is based on user searches.

Discover last-minute flight deals from London to Siem Reap. Data last updated 17 September 2026 and is based on user searches.

One-way flights from London to Siem ReapSearch for one-way flight options from London to Siem Reap. Find affordable one-way fares based on user searches. Data last updated 17 September 2026.

Search for one-way flight options from London to Siem Reap. Find affordable one-way fares based on user searches. Data last updated 17 September 2026.

Find flight deals from London to Siem Reap

Round-trip from

One-way from

Popular in

Cheapest in

Average price

Cheapflights Fare Finder

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

Best time to book a flight from London to Siem Reap

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

Cheapflights Insights

What is the cheapest month to book a flight from London to Region of Siem Reap?

How much does it cost for a return flight from London to Region of Siem Reap?

Airfare is below average for this route at the moment.

London to Region of Siem Reap flights typically cost between £745 and £843 in December.The cheapest return price found within the last 5 days was £628 on Multiple Airlines (3 Dec–14 Dec).

Reviews of airlines servicing Siem Reap

Check out reviews from past customers who have flown with Singapore Airlines,Vietnam Airlines, andAustrian Airlines from London to Siem Reap to help guide your decision. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.

Related info for your journey

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

What are the cheapest airlines to fly from London to Region of Siem Reap one-way?

What are the most popular routes from London to Region of Siem Reap?

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

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

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

What is the cheapest month to book a flight from London to Region of Siem Reap?

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 London to Siem Reap

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

Complete your trip

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

Direct flights to

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

Search flights from London to Siem Reap by cabin class

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

London and Siem Reap flights

Browse other London and Siem Reap flight options. Last updated on 17 September 2026.

Popular flight searches

Check out other popular destinations found by fellow travellers in 2026

Top 4 airlines flying from London to Siem Reap

Fly with Cheapflights

How does Cheapflights help users find flights from London to Siem Reap?

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

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

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

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Travel Smart

Cheapest flights from London to Siem Reap
Explore the most affordable flight options available from London to Siem Reap. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 17 September 2026.

Best flights from London to Siem Reap
Discover carefully curated flight deals from London to Siem Reap that have cost, travel time, and stopovers in mind to ensure you get the best travel experience. Data last updated 17 September 2026.

Last-minute flights from London to Siem Reap
Discover last-minute flight deals from London to Siem Reap. Data last updated 17 September 2026 and is based on user searches.

One-way flights from London to Siem Reap
Search for one-way flight options from London to Siem Reap. Find affordable one-way fares based on user searches. Data last updated 17 September 2026.

London to Region of Siem Reap flights typically cost between £745 and £843 in December.
The cheapest return price found within the last 5 days was £628 on Multiple Airlines (3 Dec–14 Dec).