AirHint found the following cheapest return flights from Chiang Mai (CNX) to Seoul (ICN) in September 2025 (see full year).

Return flights

24 Sep - 25 Sep	Jin Air	direct
18 Sep - 25 Sep	Jin Air	direct
11 Sep - 13 Sep	Jin Air	direct
11 Sep - 25 Sep	Jin Air	direct
10 Sep - 13 Sep	Jin Air	direct
10 Sep - 25 Sep	Jin Air	direct
16 Sep - 25 Sep	Jin Air	direct
04 Sep - 06 Sep	Eastar Jet	direct
04 Sep - 13 Sep	Eastar Jet	direct
04 Sep - 25 Sep	Eastar Jet	direct
24 Sep - 11 Oct	Jin Air	direct
25 Sep - 11 Oct	Jin Air	direct
24 Sep - 12 Oct	Jin Air	direct
26 Sep - 11 Oct	Jin Air	direct
25 Sep - 12 Oct	Jin Air	direct
24 Sep - 14 Oct	Jin Air
24 Sep - 15 Oct	Jin Air
24 Sep - 13 Oct	Jin Air
25 Sep - 14 Oct	Jin Air
25 Sep - 15 Oct	Jin Air

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

Book a cheap hotel in Seoul

Cheap car rent in Seoul

Cheapest return flights from Chiang Mai to Seoul in September from 168€

Return flights