AirHint found the following cheapest return flights from Istanbul (IST) to Seoul (ICN) in September 2026 (see full year).

Return flights

23 Sep - 03 Oct	Etihad Airways
07 Sep - 14 Sep	Qatar Airways
03 Sep - 10 Sep	Qatar Airways
04 Sep - 14 Sep	Qatar Airways
07 Sep - 13 Sep	Qatar Airways
01 Sep - 13 Sep	Qatar Airways
03 Sep - 15 Sep	Qatar Airways
17 Sep - 25 Sep	Air Astana
17 Sep - 26 Sep	Air Astana
18 Sep - 27 Sep	Air Astana
01 Sep - 08 Sep	Air Astana
24 Sep - 05 Oct	Air Astana
23 Sep - 03 Oct	Asiana Airlines	direct
24 Sep - 05 Oct	Asiana Airlines	direct

Also check the deals for one-way flights from Istanbul 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.

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Cheapest return flights from Istanbul to Seoul in September from $793

Return flights