Cheapest return flights from London to Phnom-penh in September from $639

Best time to book flights for London (LHR) to Phnom-penh (PNH) flights at AirHint

AirHint found the following cheapest return flights from London (LHR) to Phnom-penh (PNH) in September 2025 (see full year).

Return flights

26 Sep - 11 Oct China Southern
28 Sep - 12 Oct China Southern
02 Sep - 02 Oct Singapore Airlines
01 Sep - 30 Sep Singapore Airlines
10 Sep - 19 Sep Singapore Airlines
05 Sep - 27 Sep Shenzhen Airlines
20 Sep - 04 Oct Singapore Airlines
20 Sep - 27 Sep Singapore Airlines
19 Sep - 29 Sep Singapore Airlines
20 Sep - 29 Sep China Airlines
15 Sep - 19 Sep Shenzhen Airlines
29 Sep - 10 Oct Thai Airways

Also check the deals for one-way flights from London to Phnom-penh in September.

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The deals are updated regularly. The prices may go up as tickets are purchased by other travellers. Only the cheapest flights are offered. Select a price to book and secure these cheap prices.

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