AirHint found the following cheapest return flights from Adelaide (ADL) to Kathmandu (KTM) in September 2025 (see full year).

Return flights

05 Sep - 30 Oct	Virgin Australia
06 Sep - 30 Oct	Virgin Australia
06 Sep - 31 Oct	Virgin Australia
28 Sep - 27 Oct	Virgin Australia
22 Sep - 25 Oct	Jetstar
28 Sep - 31 Oct	Virgin Australia
07 Sep - 25 Sep	Malaysia Airlines
27 Sep - 27 Oct	Qantas
07 Sep - 26 Sep	Malaysia Airlines
16 Sep - 19 Sep	Malaysia Airlines
05 Sep - 31 Oct	Malaysia Airlines
15 Sep - 15 Oct	Qantas
01 Sep - 21 Sep	Qantas
07 Sep - 04 Oct	Malaysia Airlines
20 Sep - 28 Sep	Singapore Airlines

Also check the deals for one-way flights from Adelaide to Kathmandu 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 Adelaide to Kathmandu in September from $800

Return flights