Which stopover airport has the shortest connection time from London Heathrow Airport to Siem Reap?

Bangkok (BKK) has the shortest average stopover time for this route: 1h 58m.

Which stopover airport offers the lowest fares from London Heathrow Airport to Siem Reap?

Flights via Singapore (SIN) offer the lowest average return price of £734.

Which stopover airport has the shortest travel time from London Heathrow Airport to Siem Reap?

Flights connecting via Bangkok (BKK) have the shortest average one-way travel time: 13h 55m.

Which airlines fly to Siem Reap?

Singapore Airlines, Vietnam Airlines and Thai Airways are the top three most popular airlines that fly to Siem Reap from London Heathrow Airport according to our data. Singapore Airlines is the first choice among our users, with 47% of people opting to fly with this airline when travelling to Siem Reap. Keep in mind that there are 5 different airlines that fly to Siem Reap on a routine basis, so you have a few additional options to choose from.

What is the cheapest airline that flies from London Heathrow to Siem Reap–Angkor Intl?

SWISS and China Eastern are the most popular carriers operating from London Heathrow to Siem Reap–Angkor Intl

Which airport is the most popular for stopovers for flights between London Heathrow Airport and Siem Reap?

Singapore (SIN) was the most common stop: 77% of momondo users choosing one-stop flights on this route connected there.

When did momondo last update prices for flights from London Heathrow Airport to Siem Reap–Angkor Intl Airport?

Prices for flights from London Heathrow Airport to Siem Reap–Angkor Intl Airport were last updated today.

How many operators does momondo search for flights from London Heathrow Airport to Siem Reap–Angkor Intl Airport?

As of March 2026, there are 5 operators available to choose from for flights from London Heathrow Airport to Siem Reap–Angkor Intl Airport.

How old do you have to be to fly from London Heathrow Airport to Siem Reap–Angkor Intl Airport?

The minimum age for a child to fly alone is five, but airlines that offer an unaccompanied minor (UNMR) service may have their own age limitations. Flight duration, scheduling, and layovers are among the considerations that may influence age limits. We recommend that you double-check with the airline you are booking with for travel from London Heathrow Airport to Siem Reap–Angkor Intl Airport.

What documentation or ID do you need to fly to Siem Reap–Angkor Intl Airport?

The travel and health documents required for your trip to Siem Reap–Angkor Intl Airport can vary based on your itinerary and personal situation. As a rule, consider having multiple documents such as a national ID card or driver’s license, and a passport valid for six-months after you plan to arrive at Siem Reap–Angkor Intl Airport. We always recommend checking with your airline or a trusted third party such as IATA to get advice.

£367 Cheap Flights from London Heathrow Airport to Siem Reap in 2026

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Find the cheapest flights from London Heathrow Airport to Siem Reap

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Enter your travel dates to find the best prices.

21:20 - 20:10

LHR

SAI

64h 50m

3 stops

21:10 - 18:40

SAI

LHR

27h 30m

2 stops

£595China Eastern

Tue, 9 Jun - Wed, 17 Jun

21:20 - 20:10

LHR

SAI

40h 50m

3 stops

21:10 - 18:40

SAI

LHR

27h 30m

2 stops

£607China Eastern

Wed, 10 Jun - Wed, 17 Jun

21:20 - 20:10

LHR

SAI

40h 50m

3 stops

21:10 - 18:40

SAI

LHR

27h 30m

2 stops

£608China Eastern

Wed, 29 Apr - Wed, 20 May

14:40 - 18:45

LHR

SAI

22h 05m

2 stops

19:30 - 12:40

SAI

LHR

47h 10m

2 stops

£622Multiple Airlines

Thu, 7 May - Thu, 14 May

06:55 - 18:45

LHR

SAI

29h 50m

2 stops

10:30 - 10:40

SAI

LHR

30h 10m

2 stops

£634Lufthansa

Mon, 1 Jun - Mon, 8 Jun

12:10 - 18:45

LHR

SAI

24h 35m

2 stops

09:40 - 21:45

SAI

LHR

18h 05m

2 stops

£636SWISS

Tue, 9 Jun - Tue, 16 Jun

21:20 - 20:10

LHR

SAI

64h 50m

3 stops

21:10 - 18:40

SAI

LHR

27h 30m

2 stops

£645China Eastern

Tue, 21 Apr - Wed, 20 May

13:50 - 18:45

LHR

SAI

22h 55m

2 stops

09:40 - 21:45

SAI

LHR

18h 05m

2 stops

£651SWISS

Thu, 11 Jun - Tue, 16 Jun

21:20 - 08:45

LHR

SAI

29h 25m

2 stops

13:05 - 06:55

SAI

LHR

23h 50m

2 stops

£666Multiple Airlines

Wed, 29 Apr - Mon, 25 May

19:30 - 18:45

LHR

SAI

17h 15m

2 stops

09:45 - 21:45

SAI

LHR

18h 00m

2 stops

£673Multiple Airlines

Tue, 2 Jun - Tue, 9 Jun

China Eastern flights from London Heathrow Airport to Siem Reap

Our best China Eastern deals on London Heathrow Airport to Siem Reap flight tickets

China Eastern

9 Jun

LHR21:20London Heathrow

64h 50m

3 stops

SAI20:10Siem Reap–Angkor Intl

17 Jun

SAI21:10Siem Reap–Angkor Intl

27h 30m

2 stops

LHR18:40London Heathrow

£595

China Eastern

10 Jun

LHR21:20London Heathrow

40h 50m

3 stops

SAI20:10Siem Reap–Angkor Intl

17 Jun

SAI21:10Siem Reap–Angkor Intl

27h 30m

2 stops

LHR18:40London Heathrow

£607

China Eastern

29 Apr

LHR21:20London Heathrow

40h 50m

2 stops

SAI20:10Siem Reap–Angkor Intl

20 May

SAI21:10Siem Reap–Angkor Intl

27h 30m

2 stops

LHR18:40London Heathrow

£608

Emirates flights from London Heathrow Airport to Siem Reap

Our best Emirates deals on London Heathrow Airport to Siem Reap flight tickets

Emirates

7 Jun

LHR20:40London Heathrow

42h 50m

2 stops

SAI21:30Siem Reap–Angkor Intl

16 Jun

SAI23:50Siem Reap–Angkor Intl

26h 25m

2 stops

LHR20:15London Heathrow

£749

Emirates

12 Apr

LHR19:50London Heathrow

43h 40m

2 stops

SAI21:30Siem Reap–Angkor Intl

12 May

SAI23:50Siem Reap–Angkor Intl

24h 50m

2 stops

LHR18:40London Heathrow

£750

momondo Fare Finder

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

Fly from

Fly to

Route

Depart

Return

Price

Cheapest return flight

LondonSiem Reap

LHR - SAI

LHRSAI

London Heathrow

Tue 9/6

21:20-20:10

3 stops64h 50m

Siem Reap–Angkor Intl

Wed 17/6

21:10-18:40

2 stops27h 30m

£595

LondonSiem Reap

LHR - SAI

LHRSAI

London Heathrow

Wed 10/6

21:20-20:10

3 stops40h 50m

Siem Reap–Angkor Intl

Wed 17/6

21:10-18:40

2 stops27h 30m

£607

LondonSiem Reap

LHR - SAI

LHRSAI

London Heathrow

Wed 29/4

21:20-20:10

3 stops40h 50m

Siem Reap–Angkor Intl

Wed 20/5

21:10-18:40

2 stops27h 30m

£608

LondonSiem Reap

LHR - SAI

LHRSAI

London Heathrow

Thu 7/5

14:40-18:45

2 stops22h 05m

Siem Reap–Angkor Intl

Thu 14/5

19:30-12:40

2 stops47h 10m

£622

LondonSiem Reap

LHR - SAI

LHRSAI

London Heathrow

Mon 1/6

06:55-18:45

2 stops29h 50m

Siem Reap–Angkor Intl

Mon 8/6

10:30-10:40

2 stops30h 10m

£634

LondonSiem Reap

LHR - SAI

LHRSAI

London Heathrow

Tue 9/6

12:10-18:45

2 stops24h 35m

Siem Reap–Angkor Intl

Tue 16/6

09:40-21:45

2 stops18h 05m

£636

LondonSiem Reap

LHR - SAI

LHRSAI

London Heathrow

Tue 21/4

21:20-20:10

3 stops64h 50m

Siem Reap–Angkor Intl

Wed 20/5

21:10-18:40

2 stops27h 30m

£645

LondonSiem Reap

LHR - SAI

LHRSAI

London Heathrow

Thu 11/6

13:50-18:45

2 stops22h 55m

Siem Reap–Angkor Intl

Tue 16/6

09:40-21:45

2 stops18h 05m

£651

LondonSiem Reap

LHR - SAI

LHRSAI

London Heathrow

Wed 29/4

21:20-08:45

2 stops29h 25m

Siem Reap–Angkor Intl

Mon 25/5

13:05-06:55

2 stops23h 50m

£666

Fastest return journey

LondonSiem Reap

LHR - SAI

LHRSAI

London Heathrow

Tue 2/6

19:30-18:45

2 stops17h 15m

Siem Reap–Angkor Intl

Tue 9/6

09:45-21:45

2 stops18h 00m

£673

Flights are sorted by cheapest return flights first.

Showing 1-10 of 20 resultsSorted by cheapest first

How to get the cheapest flight ticket from London Heathrow Airport to Siem Reap

Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip

Prices

Airlines

Stopovers

What is the cheapest month to fly to Siem Reap?

The month of May is, on average, the cheapest month to fly to Siem Reap from London Heathrow Airport, with most prices found around £666. If you don’t want to visit Siem Reap in May, then you should wait until April to fly from London Heathrow Airport, when ticket prices are also cheap, with an average price of £699.

How far in advance should I book a flight to Siem Reap?

You are more likely to see cheaper flights to Siem Reap from London Heathrow Airport when booking weeks ahead of your departure date. In general, you can expect to find flights to Siem Reap for around £806 when searching weeks before you fly. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Siem Reap from London Heathrow Airport for as low as £667 on momondo.

Can stopping save me money on London Heathrow Airport to Siem Reap flights?

You could potentially save up to 4% on your flight if you consider stops on a London Heathrow Airport to Siem Reap flight.

When to book flights from London Heathrow Airport to Siem Reap

Are you open to changing your travel dates? Check out the ideal times to fly from London Heathrow Airport to Siem Reap according to our flight data. Find out which month and days have the cheapest flights.

Estimated return price

Cheap London Heathrow Airport to Siem Reap (LHR to SAI) flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from London Heathrow Airport to Siem Reap

Fastest flight time	22h 05m
Direct flights	None

The fastest flight from London Heathrow Airport to Siem Reap takes 22h 05m

There are no direct flights from London Heathrow Airport to Siem Reap. There are no popular flight routes from London Heathrow Airport to Siem Reap.

Search flight deals

How far is London Heathrow to Siem Reap–Angkor Intl by plane?
A flight from London Heathrow to Siem Reap–Angkor Intl will travel around 6091.7 mi. In terms of flight time, this usually takes a little over 22h 05m.
When did momondo last update prices for flights from London Heathrow Airport to Siem Reap–Angkor Intl Airport?
Prices for flights from London Heathrow Airport to Siem Reap–Angkor Intl Airport were last updated today.
How many operators does momondo search for flights from London Heathrow Airport to Siem Reap–Angkor Intl Airport?
As of March 2026, there are 5 operators available to choose from for flights from London Heathrow Airport to Siem Reap–Angkor Intl Airport.
How old do you have to be to fly from London Heathrow Airport to Siem Reap–Angkor Intl Airport?
The minimum age for a child to fly alone is five, but airlines that offer an unaccompanied minor (UNMR) service may have their own age limitations. Flight duration, scheduling, and layovers are among the considerations that may influence age limits. We recommend that you double-check with the airline you are booking with for travel from London Heathrow Airport to Siem Reap–Angkor Intl Airport.
What documentation or ID do you need to fly to Siem Reap–Angkor Intl Airport?
The travel and health documents required for your trip to Siem Reap–Angkor Intl Airport can vary based on your itinerary and personal situation. As a rule, consider having multiple documents such as a national ID card or driver’s license, and a passport valid for six-months after you plan to arrive at Siem Reap–Angkor Intl Airport. We always recommend checking with your airline or a trusted third party such as IATA to get advice.
What is the most popular airline from London Heathrow Airport to Siem Reap?
Based on momondo bookings for this flight route, the most popular airline on flight routes from London Heathrow Airport to Siem Reap is Singapore Airlines (43% of total bookings). The next most popular airlines are Vietnam Airlines (25%), Thai Airways (15%), and Austrian Airlines (9%).

Best airlines flying from London Heathrow Airport to Siem Reap

Compare and see reviews for airlines that fly from London Heathrow Airport to Siem Reap with momondo

Airline	Rating	Free Cancellation	Price
Austrian Airlines	PriceFrom £543	Free Cancellation	Rating 7.6 900 reviews	Search Austrian Airlines flights
Lufthansa	PriceFrom £602	Free Cancellation	Rating 6.8 7,862 reviews	Search Lufthansa flights
Vietnam Airlines	PriceFrom £621	Free Cancellation	Rating 7.7 245 reviews	Search Vietnam Airlines flights
Singapore Airlines	PriceFrom £669	Free Cancellation	Rating 8.2 1,483 reviews	Search Singapore Airlines flights
Thai Airways	PriceFrom £865	Free Cancellation	Rating 7.8 394 reviews	Search Thai Airways flights

Why use momondo?

Why should I use momondo to find a flight deal from London to Siem Reap?

momondo collates all your flight options in one place and lets you filter them to find the perfect flight from London to Siem Reap. momondo saves you time and could save you money on your trip.

Can I find flights from London to Siem Reap with flexible booking policies on momondo?

Flights from London to Siem Reap with flexible booking policies can be found by using the search form above and then selecting our dedicated flexible booking filter, which will highlight only the flights where this policy is applied.

How can momondo help me find flights from London to Siem Reap?

Once you have performed a search in the form on the page, momondo provides useful filters and insights. We can show you the cheapest days and times to fly as well as help filter your options to help you make an informed choice when booking flights to Siem Reap from London.

I’m not ready to book a flight from London to Siem Reap right now. Can momondo alert me if prices change?

Price alerts on flights to Siem Reap from London are quick and easy to set up on momondo. Simply perform a search and select the price alert feature. It is as simple as that.

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Our best Emirates deals on London Heathrow Airport to Siem Reap flight tickets

momondo Fare Finder

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

See travel insights to Siem Reap from

How to get the cheapest flight ticket from London Heathrow Airport to Siem Reap

What is the cheapest month to fly to Siem Reap?

How far in advance should I book a flight to Siem Reap?

Can stopping save me money on London Heathrow Airport to Siem Reap flights?

What is the cheapest airline that flies from London Heathrow to Siem Reap–Angkor Intl?

Which airlines fly to Siem Reap?

Which airport is the most popular for stopovers for flights between London Heathrow Airport and Siem Reap?

Which stopover airport offers the lowest fares from London Heathrow Airport to Siem Reap?

Which stopover airport has the shortest travel time from London Heathrow Airport to Siem Reap?

Which stopover airport has the shortest connection time from London Heathrow Airport to Siem Reap?

When to book flights from London Heathrow Airport to Siem Reap

Cheap London Heathrow Airport to Siem Reap (LHR to SAI) flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from London Heathrow Airport to Siem Reap

Fastest flight time

Direct flights

Best airlines flying from London Heathrow Airport to Siem Reap

Compare and see reviews for airlines that fly from London Heathrow Airport to Siem Reap with momondo

Why use momondo?

An easier way to manage your Siem Reap trip

We make it super easy to schedule, organise and travel with friends or family. Trips is free – and available to use no matter where you book.

Get notified when prices go down

Daily price changes in your inbox - only with Price Alerts.

Find better results for your trip to Cambodia

Fly your favourite airline to Siem Reap

Airlines are sorted and displayed according to clicks in the past 7 days on momondo

Cabin classes currently available on flights to Siem Reap

List of cabin classes available on flights landing in Siem Reap. Availability may vary depending on flight origin and airline.

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