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Cheap flights from Siem Reap to London Heathrow Airport from £305

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 6/10. Fares are subject to change and may not be available on all flights or dates of travel.
SAI — LHR
29 Jul — 5 Aug1
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 29 June 2026.

Thu 16/719:35
SAI
-
LHR
2 stops31h 05m
Multiple Airlines
Tue 28/716:10
LHR
-
SAI
2 stops34h 50m
Multiple Airlines
Deal found 26/6£831

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 29 June 2026.

Round-trip from

£831

One-way from

£305
16/7-28/7
  • 16/7-28/7
  • 4 total stops
  • 65h 55m total
  • Siem Reap to London
Search Deals
Vietnam Airlines
  • Vietnam Airlines
  • 6/10
  • 1 total stop
  • 28h 50m 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 29 June 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
Fastest return journey

Siem ReapLondon

SAI - LHR

SAILHR

Siem Reap–Angkor Intl

Thu 16/7

19:35-20:40

2 stops31h 05m

London Heathrow

Tue 28/7

16:10-09:00

2 stops34h 50m

£831
Cheapest one-way

Siem ReapLondon

SAI - LHR

SAILHR

Siem Reap–Angkor Intl

Mon 5/10

19:10-17:50

1 stop28h 40m

£306

Siem ReapLondon

SAI - LHR

SAILHR

Siem Reap–Angkor Intl

Thu 19/11

13:20-14:45

2 stops32h 25m

£323

Siem ReapLondon

SAI - LHR

SAILHR

Siem Reap–Angkor Intl

Fri 2/10

19:05-19:50

3 stops30h 45m

£361

Siem ReapLondon

SAI - LHR

SAILHR

Siem Reap–Angkor Intl

Thu 1/10

19:10-20:00

2 stops30h 50m

£367

Siem ReapLondon

SAI - LHR

SAILHR

Siem Reap–Angkor Intl

Sat 1/8

15:10-15:05

2 stops29h 55m

£395

Siem ReapLondon

SAI - LHR

SAILHR

Siem Reap–Angkor Intl

Mon 24/8

18:55-19:20

2 stops30h 25m

£432

Siem ReapLondon

SAI - LHR

SAILHR

Siem Reap–Angkor Intl

Mon 24/8

12:55-16:10

2 stops33h 15m

£454
Fastest single journey

Siem ReapLondon

SAI - LHR

SAILHR

Siem Reap–Angkor Intl

Thu 1/10

10:30-08:00

1 stop27h 30m

£525

Flights are sorted by cheapest return flights first.

Deals found on 26/6

Sorted 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.
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.

  • 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.

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
Wembley
Gatwick
Croydon
Slough
Ilford
Hayes
Brentford
Colchester
Northampton
Watford
Kingston upon Thames
Swindon
Eastbourne
Poole
Southall
Aylesbury
Romford

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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 Gatwick flights
Siem Reap to Heathrow flights

Fly with Cheapflights

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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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