AirHint found the following cheapest return flights from Seoul (ICN) to Kathmandu (KTM) in December 2025 (see full year).

Return flights

05 Dec - 31 Dec	Air China
19 Dec - 28 Jan	Air China
15 Dec - 31 Dec	Air China
28 Dec - 07 Jan	China Southern
15 Dec - 15 Jan	Air China
18 Dec - 27 Jan	Air China
23 Dec - 27 Jan	China Southern
27 Dec - 09 Jan	China Southern
27 Dec - 22 Jan	China Southern
31 Dec - 08 Jan	China Southern
31 Dec - 11 Jan	China Southern
27 Dec - 06 Jan	China Southern
11 Dec - 18 Dec	China Southern
19 Dec - 27 Dec	China Eastern
02 Dec - 12 Dec	China Southern
10 Dec - 20 Dec	Air China
08 Dec - 20 Dec	Air China
03 Dec - 09 Dec	Air China
08 Dec - 16 Dec	Air China
04 Dec - 09 Dec	Air China

Also check the deals for one-way flights from Seoul to Kathmandu 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.

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Cheapest return flights from Seoul to Kathmandu in December from 324€

Return flights