AirHint found the following cheapest return flights from Sydney (SYD) to Phnom-penh (PNH) in December 2025 (see full year).

Return flights

10 Dec - 23 Dec	AirAsia X
10 Dec - 21 Dec	AirAsia X
10 Dec - 29 Dec	AirAsia X
10 Dec - 28 Dec	AirAsia X
10 Dec - 27 Dec	AirAsia X
10 Dec - 22 Dec	AirAsia X
10 Dec - 30 Dec	AirAsia X
10 Dec - 25 Dec	AirAsia X
08 Dec - 23 Dec	AirAsia X
08 Dec - 21 Dec	AirAsia X
16 Dec - 01 Jan	AirAsia X
15 Dec - 01 Jan	AirAsia X
17 Dec - 01 Jan	AirAsia X
16 Dec - 02 Jan	AirAsia X
16 Dec - 04 Jan	AirAsia X
15 Dec - 02 Jan	AirAsia X
15 Dec - 04 Jan	AirAsia X
30 Dec - 10 Jan	AirAsia X
31 Dec - 10 Jan	AirAsia X
16 Dec - 03 Jan	AirAsia X

Also check the deals for one-way flights from Sydney to Phnom-penh in December.

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.

Book a cheap hotel in Phnom-penh

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Cheapest return flights from Sydney to Phnom-penh in December from $768

Return flights