Find Cheap Flights from London to Siem Reap | Cheapflights

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Cheap flight deals from London to Siem Reap

Popular in	December
Cheapest in	September
Average price	£788

Highest demand for flights based on searches. 5% potential increase in price (£42 potential increase over avg. return price).

Cheapest flight prices on average. 4% potential price decrease (£28 potential savings vs. average return price).

Average for round-trip flights in October 2025

Cheapflights Insights

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

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

Currently, September is the cheapest month in which you can book a flight from London to Region of Siem Reap (average of £621). Flying from London to Region of Siem Reap in August is currently the most expensive (average of £911). 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.

Reviews of airlines servicing Siem Reap

Check out reviews from past customers who have flown with Singapore Airlines, Thai Airways, andVietnam 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

8.1

Very Good

Reviews

1 / 20

10.0

Excellent

Anonymous,Sept 2025

BCN - SIN

Staff at Barcelona were fantastic, they helped me change a flight and nothing was any problem. Thank you Dina.

Singapore Airlines

8.1

Very Good

Singapore Airlines

8.1

Very Good

Reviews

1 / 20

10.0

Excellent

Anonymous,Sept 2025

BCN - SIN

Staff at Barcelona were fantastic, they helped me change a flight and nothing was any problem. Thank you Dina.

7.8

Good

Singapore Airlines

8.1

Very Good

Reviews

1 / 20

10.0

Excellent

Anonymous,Sept 2025

BCN - SIN

Staff at Barcelona were fantastic, they helped me change a flight and nothing was any problem. Thank you Dina.

Vietnam Airlines

7.5

Good

Singapore Airlines

8.1

Very Good

Reviews

1 / 20

10.0

Excellent

Anonymous,Sept 2025

BCN - SIN

Staff at Barcelona were fantastic, they helped me change a flight and nothing was any problem. Thank you Dina.

British Airways

6.7

Okay

Singapore Airlines

8.1

Very Good

Reviews

1 / 20

10.0

Excellent

Anonymous,Sept 2025

BCN - SIN

Staff at Barcelona were fantastic, they helped me change a flight and nothing was any problem. Thank you Dina.

Related info for your journey

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, September is the cheapest month in which you can book a flight from London to Region of Siem Reap (average of £621). Flying from London to Region of Siem Reap in August is currently the most expensive (average of £911). 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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Direct flights to

Top 5 airlines flying from London to Siem Reap

Airline	Cheapest	Average	Flexibility	On-time
Austrian Airlines	Cheapest£593	Average£755	FlexibilityNo cancel fee	On-time78%	Search Austrian Airlines flights
Vietnam Airlines	Cheapest£627	Average£732	FlexibilityNo cancel fee	On-time81%	Search Vietnam Airlines flights
Singapore Airlines	Cheapest£648	Average£843	FlexibilityNo cancel fee	On-time81%	Search Singapore Airlines flights
Lufthansa	Cheapest£747	Average£783	FlexibilityNo cancel fee	On-time76%	Search Lufthansa flights
Thai Airways	Cheapest£876	Average£965	FlexibilityNo cancel fee	On-time77%	Search Thai Airways flights

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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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