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Cheap flights from Siem Reap to London Heathrow Airport from £252

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 17/10. Fares are subject to change and may not be available on all flights or dates of travel.
SAI — LHR
13 Sep — 20 Sep1
1 adult
1 adult, Economy, 0 bags

Cheap flight deals from Siem Reap to Heathrow

Enter your travel dates to find the best prices.

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 14 August 2026.

Wed 9/909:40 -
2 stops35h 40m
Fri 18/912:35 -
2 stops26h 35m
Deal found 13/8£697
Sat 12/909:40 -
2 stops27h 15m
Sat 19/921:45 -
2 stops31h 30m
Deal found 13/8£765
Thu 13/817:55 -
2 stops29h 45m
Thu 3/921:45 -
2 stops31h 30m
Deal found 9/8£793
Fri 18/1219:25 -
2 stops44h 45m
Fri 1/110:20 -
2 stops39h 55m
Deal found 10/8£827
Wed 16/1209:55 -
2 stops39h 15m
Fri 1/120:55 -
2 stops29h 20m
Deal found 10/8£846
Fri 28/821:10 -
2 stops27h 30m
Thu 10/908:45 -
2 stops28h 10m
Deal found 11/8£852
Fri 18/1219:25 -
2 stops44h 45m
Wed 30/1216:15 -
2 stops37h 25m
Deal found 10/8£853
Mon 21/1209:55 -
2 stops39h 15m
Fri 1/120:55 -
2 stops29h 20m
Deal found 10/8£854
Wed 16/1209:55 -
2 stops39h 15m
Wed 30/1220:55 -
2 stops29h 20m
Deal found 10/8£855
Tue 15/1209:55 -
2 stops27h 45m
Thu 31/1213:55 -
2 stops36h 20m
Deal found 10/8£863
Wed 16/1209:55 -
2 stops39h 15m
Tue 29/1219:20 -
2 stops54h 55m
Deal found 10/8£869
Sun 20/1209:55 -
2 stops27h 45m
Thu 31/1220:55 -
2 stops32h 45m
Deal found 10/8£871

Find flight deals from Siem Reap to Heathrow

Keep the following information in mind while searching for Siem Reap to Heathrow flight deals. Data was last updated 14 August 2026.

Round-trip from

£697

One-way from

£252
9/9-18/9
  • 9/9-18/9
  • 4 total stops
  • 62h 15m total
  • Siem Reap to London
Search Deals
17/10
  • 17/10
  • 2 total stops
  • 54h 15m total
  • Siem Reap to London
Search Deals

Cheapflights Fare Finder

 
Customise your flight search to find flights from Siem Reap to Heathrow that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 858,174 searches. Data last updated 14 August 2026.
Use the filters below to find and compare flights from Siem Reap to London Heathrow Airport that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest return flight

Siem ReapLondon

SAI Siem Reap–Angkor Intl - LHR London Heathrow

SAILHR

Siem Reap–Angkor Intl

Sat 12/9

09:40-06:55

2 stops27h 15m

London Heathrow

Sat 19/9

21:45-11:15

2 stops31h 30m

£765

Siem ReapLondon

SAI Siem Reap–Angkor Intl - LHR London Heathrow

SAILHR

Siem Reap–Angkor Intl

Tue 22/12

19:25-09:10

2 stops20h 45m

London Heathrow

Tue 5/1

16:15-12:40

2 stops37h 25m

£846

Siem ReapLondon

SAI Siem Reap–Angkor Intl - LHR London Heathrow

SAILHR

Siem Reap–Angkor Intl

Fri 28/8

21:10-18:40

2 stops27h 30m

London Heathrow

Thu 10/9

08:45-18:55

2 stops28h 10m

£852

Siem ReapLondon

SAI Siem Reap–Angkor Intl - LHR London Heathrow

SAILHR

Siem Reap–Angkor Intl

Mon 21/12

09:55-06:40

2 stops27h 45m

London Heathrow

Thu 31/12

20:55-09:15

2 stops29h 20m

£871

Siem ReapLondon

SAI Siem Reap–Angkor Intl - LHR London Heathrow

SAILHR

Siem Reap–Angkor Intl

Sun 20/12

09:55-14:30

2 stops35h 35m

London Heathrow

Wed 30/12

20:55-12:40

2 stops32h 45m

£871

Siem ReapLondon

SAI Siem Reap–Angkor Intl - LHR London Heathrow

SAILHR

Siem Reap–Angkor Intl

Fri 18/12

21:30-07:15

1 stop16h 45m

London Heathrow

Sat 2/1

11:00-20:30

1 stop26h 30m

£873
Fastest return journey

Siem ReapLondon

SAI Siem Reap–Angkor Intl - LHR London Heathrow

SAILHR

Siem Reap–Angkor Intl

Tue 22/12

20:30-07:15

1 stop17h 45m

London Heathrow

Tue 5/1

11:00-17:40

1 stop23h 40m

£903

Siem ReapLondon

SAI Siem Reap–Angkor Intl - LHR London Heathrow

SAILHR

Siem Reap–Angkor Intl

Mon 21/12

21:30-07:15

1 stop16h 45m

London Heathrow

Wed 30/12

11:00-19:40

1 stop25h 40m

£942

Siem ReapLondon

SAI Siem Reap–Angkor Intl - LHR London Heathrow

SAILHR

Siem Reap–Angkor Intl

Sun 20/12

17:55-07:15

1 stop20h 20m

London Heathrow

Thu 31/12

11:00-20:30

1 stop26h 30m

£942
Cheapest one-way

Siem ReapLondon

SAI Siem Reap–Angkor Intl - LHR London Heathrow

SAILHR

Siem Reap–Angkor Intl

Sat 17/10

19:05-19:20

2 stops54h 15m

£252

Flights are sorted by cheapest return flights first.

Deals found on 10/8

Showing 1-10 of 18 resultsSorted by cheapest first
1
2

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.
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

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

Related info for your journey

Find useful and relevant information for your journey from Siem Reap to Heathrow. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

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

    Etihad Airways can get you from Region of Siem Reap to London Heathrow Airport in just under 27h 45m. Your travel time can differ by up to . The distance from Region of Siem Reap to London Heathrow Airport is about 6106 mi.

  • 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.

See more FAQs

Travelling to a place near London Heathrow Airport?

Book flights to London Heathrow Airport if you plan to visit one of these locations
Hounslow
Milton Keynes
Luton
Gatwick
Wembley
Ilford
Slough
Hayes
Croydon
Colchester
Brentford
Eastbourne
Northampton
Watford
Southend-on-Sea
Swindon
Enfield
Kingston upon Thames
Southall
Poole

Browse thousands of different options on Cheapflights for your next trip

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Alternative routes for Siem Reap to Heathrow

See prices for flight routes from nearby airports that may be better suited for you.
Siem Reap to Heathrow flights
Siem Reap to Gatwick flights

Fly with Cheapflights

Find the best flight deals on Cheapflights, where travellers can enjoy low prices and a wide availability of flights to their desired destinations.

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

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?

Millions of users choose and trust Cheapflights to book the best flight deals from Siem Reap to Heathrow for free. We help you search and compare prices from hundreds of airlines for the right flight just for you.

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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