£365 Find Cheap Flights from London to Siem Reap

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from London to Siem Reap departing on 14/6. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
1 adult
1 adult, Economy, 0 bags

KAYAK searches hundreds of travel sites at once for deals on flights to Siem Reap

 
These are the airlines KAYAK users have selected most often from within our search results in flight searches from London to Siem Reap, as well as popular online travel agencies
These are the airlines KAYAK users have selected most often from within our search results in flight searches from London to Siem Reap, as well as popular online travel agencies
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Flight Deals

Book Cheap London to Siem Reap Plane Tickets

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for return flights from London to Siem Reap that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.
Discover the best prices for you by selecting your travel dates on KAYAK.

Recent return flight deals from London to Siem Reap

Fri, 12 Jun - Thu, 25 Jun
Etihad Airways Logo
21:45 - 09:00
LHR
-
SAI
29h 15m
2 stops
Etihad Airways Logo
15:10 - 07:00
SAI
-
LHR
21h 50m
2 stops
£584Etihad Airways
Fri, 12 Jun - Thu, 25 Jun
Etihad Airways Logo
09:30 - 17:50
LHR
-
SAI
50h 20m
2 stops
Etihad Airways Logo
15:10 - 18:45
SAI
-
LHR
33h 35m
2 stops
£585Etihad Airways
Thu, 28 May - Thu, 18 Jun
Etihad Airways Logo
09:30 - 11:15
LHR
-
SAI
19h 45m
2 stops
Etihad Airways Logo
15:10 - 07:00
SAI
-
LHR
21h 50m
2 stops
£591Etihad Airways
Thu, 17 Sep - Thu, 24 Sep
SWISS Logo
09:25 - 18:55
LGW
-
SAI
27h 30m
2 stops
SWISS Logo
09:40 - 08:25
SAI
-
LGW
28h 45m
2 stops
£594SWISS
Tue, 25 Aug - Tue, 22 Sep
SWISS Logo
18:40 - 18:55
LHR
-
SAI
42h 15m
2 stops
SWISS Logo
09:40 - 16:25
SAI
-
LHR
36h 45m
2 stops
£607SWISS
Thu, 17 Sep - Thu, 24 Sep
Multiple Airlines Logo
06:55 - 18:55
LHR
-
SAI
30h 00m
2 stops
Multiple Airlines Logo
09:40 - 07:55
SAI
-
LHR
28h 15m
2 stops
£632Multiple Airlines
Thu, 17 Sep - Thu, 24 Sep
Multiple Airlines Logo
11:35 - 20:10
LGW
-
SAI
26h 35m
3 stops
Multiple Airlines Logo
12:55 - 06:55
SAI
-
LGW
24h 00m
2 stops
£700Multiple Airlines
Fri, 30 Oct - Tue, 15 Dec
Emirates Logo
14:05 - 21:10
STN
-
SAI
24h 05m
2 stops
Emirates Logo
23:50 - 17:55
SAI
-
STN
25h 05m
2 stops
£748Emirates
Fri, 30 Oct - Tue, 15 Dec
Emirates Logo
13:35 - 21:10
LGW
-
SAI
24h 35m
2 stops
Emirates Logo
23:50 - 20:50
SAI
-
LGW
28h 00m
2 stops
£754Emirates
Fri, 30 Oct - Sat, 12 Dec
China Eastern Logo
10:30 - 21:00
LGW
-
SAI
27h 30m
3 stops
China Eastern Logo
22:00 - 06:30
SAI
-
LGW
39h 30m
3 stops
£764China Eastern
Booking Insights

KAYAK's insights & trends for London to Siem Reap flights

Get data-powered insights and trends into flights from London to Siem Reap to help you find the cheapest flights, the best time to fly and much more.

How much is a return flight from London to Region of Siem Reap?

This analysis is based on the cheapest return trip price found on KAYAK in the last 12 months by searching for a flight from London to Region of Siem Reap departing in June.

What is the cheapest month to fly from London to Siem Reap?

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from London to Siem Reap, removes the top 0.1% to account for outliers, and then takes the median of all values for each month.

The cheapest month for flights from London to Siem Reap is May, when tickets cost £523 (return) on average. On the other hand, the most expensive months are July and August, when the average cost of return tickets is £901 and £758 respectively.

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

To calculate weekly average prices, KAYAK takes all prices for each week before departure over the last year for round-trip flights from London to Siem Reap, removes the top 0.1% to account for outliers, and then takes the average of all the values for each week.

To get a below-average price on a flight from London to Siem Reap, you should book around 3 weeks before departure, which saves you about 45% compared to booking last-minute. For the absolute cheapest price, our data suggests you should book 12 weeks before departure.

Good to know - Cheap tickets from London to Siem Reap

Low seasonJuly
Best time to beat the crowds but there is an average 24% increase in price.
Most popular time to fly and prices are also 6% lower on average.

FAQs - booking Siem Reap flights

  • How does KAYAK find such low prices on flights from London to Siem Reap?

    KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from London to Siem Reap.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from London to Siem Reap?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight from London to Siem Reap is likely to change within 7 days, so travellers know whether to wait or book now.

  • What is the Hacker Fare option on flights from London to Siem Reap?

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional return ticket. You could then fly from London to Siem Reap with an airline and back with another airline.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from London to Siem Reap?

    Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying from London to Siem Reap up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

Reviews of the top 5 airlines flying from London to Siem Reap

 
See real verified KAYAK customer reviews for airlines flying from London to Siem Reap. Airline scores are aggregated from all reviews left by passengers on KAYAK after flying with an airline. KAYAK doesn’t show reviews that are older than 5 years. Learn how KAYAK collects reviews.
Need help choosing which airline to fly with from London to Siem Reap? KAYAK airline reviews give an overall score for each airline based on loads of factors, including comfort, boarding, in-flight entertainment and more, to make your decision easier. See airline scores according to verified KAYAK customer reviews.
8.2
Singapore AirlinesOverall score based on 1506 reviews
8.0Comfort
8.0Entertainment
8.3Boarding
7.8Food
8.6Crew
Airline reviews

Really great service throughout and the food was really nice. I can highly recommend thank you very much.

10.0 ExcellentPeter, Apr 2026
LHR - BKI
Read more Singapore Airlines reviews

Really great service throughout and the food was really nice. I can highly recommend thank you very much.

Kayak really screwed up by offloading the booking to a third party. They were completely inept and caused a bunch of toil. I will never use Kayak again.

A little more room from the reclining seat in the front of me.

I loved the full Taylor Swift selection but felt that the other selections were limited, didn’t span the popular music eras nor a wide enough range of music genres. BUT the seat and bed were GREAT (it was wide, long enough, had great storage, firm enough to uphold body postural comfort). Outstanding crew and really great food - gourmet innovative dim sum breakfast so different from the boring standard fare offered by many other business class products.

Overall were very good and I was satisfied w/ all the food and services.

Food was served to different people at different times and it wasn't clear why. The crew apologized for the wait. But it felt odd and inconsistent. They could use charging ports on each of the seats. Mine didn't have any. Also, they could've offered more snacks. It was a 12+ hour flight and no snacks were ever offered. Everything else was OK.

No frills airline with minimal leg room and no entertainment

I wish there was a little more leg room between the seats. The recline was good and seats overall were comfortable. I also didn’t like the 2-4-2 configuration.

The crew was very courteous and professional. the flight is relatively clean and comfortable.

Best service airline. The cabin crew is attentive and friendly. Inflight entertainment system is good

This777-300 is configured 2/3/2 for Biz class straight out of the 80s!!! Not to mention seats are narrow, bed does NOT FULLY RECLINE FLAT as advertised, and purser didn’t know that!! ARM REST HAS A REMOTE TABLET ON IT FURTHER CONFINING THE ALREADY NARROW SPACE!!! WHO thought this was a good design?? After flying the new A350-900 biz class Montreal to Dubai , this was a total let down!!

There is an issue with A380 when it arrives in Munich, because a business class passengers like me have to wait for the first class passengers to disembark, which takes some time while you are also offloading economy passengers this causes an issue at customs where your business class passengers end up behind a large bulk of economy passengers This is a frustration and the early dislocation should be and is supposed to be a benefit of business class

The journey was nice, all the crews were very good and services are excellent

Great flight - Clubhouse met our needs, and the staff provided good service. Boarding felt a little chaotic, but given the size of the aircraft, it's always going to be challenging. Whilst the crew were friendly, the number of passengers meant that we received our breakfast items, but had finished breakfast before we were served a drink. Lunch was much better organised, and throughout the flight, the crew were attentive. Found the seats and ICE to be excellent. Disembarkation was fine, and everything possible to expedite the process was being done.

I take emirates because of direct flights Otherwise no Cabin crew niot friendly and never friendly across the airlines Planes old inside not renewd .. this is not an issue The issue is the poor service

No kids provided. Instead we were told to have contacted the airline that we have kids and require kids meals. We were not the only ones who inquired about kids meals. It’s odd. Emirates and other airlines give kids meals as standard and before the adult food comes out. The rice in our meals was gluggy and under cooked. The chicken was also raw. Sadly not the best experience with Finn Air. The hostesses tried to compensate with the snacks and drinks but missed the mark by a long way. Especially when paying Emirates/Qantas prices

Sadly I couldn't get the food I requested as it was out. Also, if you don't want to be woken up make sure the crew knows it. My wife was woken on every service.

This was my first time flying with Emirates. Overall, the experience was very good. I thought the seats in economy would have been a bit more comfortable, but, they seem to be on par with other airlines. The food was excellent and very satisfying. If you can afford it, I would definitely suggest upgrading to at lest premium economy seats for long haul flights.

Can’t complain Only downside was the Kiosk passport check and customs clearance at Melbourne. When will they improve that service🤔

We loved flying with Emirates in business class, the staff were fabulous, going above & beyond

HAVING ANNOUNCEMENTS FOR PEOPLE TO BOARD ACCORDING TO GROUP IS ESSENTIAL N ENSURING N CUTTING OF QUEUES, EXCEPT FOR PRIORITY CLASS PASSENGERS ON A SEPARATE Q

We still get drinks and a snack. Love the gift bags too.

business class is old but still done very well by the team.

Excellent airline. The plane was clean and the staff were very attentive

Good experience although the boarding gate is at the terminal extension hence need to leave lounge to head over earlier.

Thai Royal First is very good. Easy check in , Private room in the first class lounge and escort from ticketing to the plane. Once on board crew was very polite, food was outstanding, and the ride was smooth as silk. Restrooms were especially clean. Great Experience

I'm not interested in improving the airline. Therefore, I won't explain this in more detail. Next time I'll try a different one.

The flight (boarding) was delayed by 40-50 minutes and there was very crowed. They need to improve on the timeliness & boarding process. (They asked passenger to board in groups, but the 2nd group was standing there waiting for 20 minutes!). However, services from the crew was very good, also the food was good as well. I also found the legroom was quite comfortable.

Need to improve on punctuality. My flight was delayed by 1 hour.

Seats were uncomfortable and the vegetarian meal was awful. Some of the entertainment didn't work.

I thought I already provided this feedback. 12 hours with no wifi is unacceptable. Lay flat is nice but a bit cramped.

The vietnam airlines app was not able to allow checkin with the confirmation nor with the ticket number. This led to quite a bit of consternation. Speaking with a colleague from Hanoi, he did tell me that their app is not the best. It may be best to inform travelers to only use the link and to plan on checking in at the airport for this airline. The check-in was very easy and the staff were excellent.

flight departure was late, with no updates on status of departure

The aircraft was little tired but the food and service was outstanding

It was ok, it felt more like an internal flight than an international flight so I guess expected a slightly better standard. Nothing really wrong with it but there was no inflight entertainment. Food and service was good.

This was our fourth domestic flight with Vietnam Airlines, and once again we found the experience very suitable. Check-in was easy and efficient. They did take our carry-on luggage, but that was fine. I’m actually happy not to deal with it on such a short flight. The flight was just over an hour, departed on time, and we climbed above the clouds into a beautiful sunset. Even on such a short flight, they served water, which we appreciated. Luggage came out into carousel in Nha Trang in good time and off we went to meet our GRAB. Also, Vietnam Airlines have easy to locate ground level offices in cities and towns where you can get assistance with staff. I liked this service as we did go visit one in Nha Trang. We would definitely recommend Vietnam Airlines and wouldn’t hesitate to fly with them again.

Really good 👍 This was our first time flying with Vietnam Airlines. It was a short domestic flight, so no meal service, but boarding was organized and the flight departed and arrived on schedule. The flight attendants were professional and neatly presented. All in all, a very good first experience. We would recommend Vietnam Airlines.

We flew with their partner VESCO on a small plane, it was a really good flight. There was no food or entertainment as it’s a one hour hopper flight.

The flight boarded and departed pretty much on time as it’s just a one hour flight there is no food or entertainment so I marked that at the neutral but they do offer water and I’m sure if you needed some food you could bring your own onboard. This was our third internal flight with Vietnam Airways and I recommend them.

This is a very short commuter flight, so there is no food or flight entertainment. Hence, I marked it in the neutral flight left on time. The plane was full pretty much and it was a pretty easy flight overall very good.

The map feature on the display at the seat had challenges. The biggest issue was the flight had no WIFI. Most of the smaller planes now have free WIFI. American Airlines on the flight over had WIFI you could purchase. With 8-10 hours on a single flight, the ability to do work via WIFI is essential!!

A shout-out to the flight attendent, Lauren, who was the main person assisting me. She was amazing - perfect balance of bright, cheerful, engaging, yet formal

Cramped seating but standard in all smaller aircrafts today no matter what airlines. Crew very helpful, friendly & attentive so makes up for that.

Wonderful business class flight in a lovely new plane with an excellent crew

OK, except for a cabin attendant's lack of attention.

efficient. on time. cabin crew were very professional and very nice to deal with. would definately fly BA again.

It was great overall. A few slight improvements could be made on the onboarding process at the Gates with announcements and clarity of communications (both at the gate and in flight). The movies in the entertainment options could be improved for bollywood, hollywood.

I alrady responded to this request, and expllaned at length that this was the worst flying experience in my 77 years. I will NEVER fly BA again.

Airbus A350 is poorly designed for wheelchair users and reduced mobility passengers. The angle of the pods makes it awkward to transfer. I was able to but I have ab stability. It could be a real challenge for people with more severe mobility impairments. You'd think Airbus would have come up with a solution for this or thought more about us disabled folks more when designing this aircraft.

The crew has always been great on BA. They are very friendly and accommodating. I like that they have vegetarian options already in the menu. And the free wine is a nice perk.) I noticed (both directions of my trip) minor upgrades/ replacements needed on the plane itself (touch screen didn't work with touch; bathroom light didn't go on). However, this is one of my favorite airlines.

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

Cabin class types available on flights to Siem Reap

Cabin classes available on flights to Siem Reap. Prices are the lowest found on KAYAK over the last 7 days. Price and availability is not guaranteed.