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

Return flights

15 Sep - 26 Sep	Ryanair
10 Sep - 17 Sep	Ryanair
20 Sep - 23 Sep	Ryanair
09 Sep - 26 Sep	Ryanair
18 Sep - 06 Oct	Ryanair
20 Sep - 22 Sep	Ryanair
08 Sep - 16 Sep	Ryanair
16 Sep - 25 Sep	Ryanair
12 Sep - 21 Sep	Ryanair
20 Sep - 04 Oct	Ryanair
21 Sep - 26 Sep	Ryanair
24 Sep - 05 Oct	Ryanair
06 Sep - 29 Sep	Ryanair
25 Sep - 05 Oct	Emirates
14 Sep - 04 Oct	Emirates
30 Sep - 12 Oct	Emirates
27 Sep - 04 Oct	Emirates
26 Sep - 17 Oct	Emirates
01 Sep - 02 Oct	Emirates

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

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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Cheapest return flights from London to Phnom-penh in September from 757€

Return flights