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

Return flights

01 Sep - 10 Sep	Wizz Air UK
16 Sep - 30 Sep	SunExpress
21 Sep - 28 Sep	Wizz Air UK
20 Sep - 06 Oct	Wizz Air UK
29 Sep - 10 Oct	easyJet
28 Sep - 11 Oct	Wizz Air UK
20 Sep - 27 Sep	easyJet
01 Sep - 06 Oct	easyJet
08 Sep - 21 Sep	Ryanair
08 Sep - 19 Sep	Ryanair
08 Sep - 18 Sep	Ryanair
21 Sep - 02 Oct	Wizz Air UK
14 Sep - 21 Sep	Wizz Air UK
15 Sep - 29 Sep	Wizz Air
08 Sep - 15 Sep	Ryanair
27 Sep - 11 Oct	easyJet
23 Sep - 05 Oct	easyJet
13 Sep - 06 Oct	Wizz Air
20 Sep - 02 Oct	Wizz Air UK
19 Sep - 04 Oct	easyJet

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 672€

Return flights