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

Return flights

12 Sep - 20 Sep	Asiana Airlines
14 Sep - 21 Sep	Air China
08 Sep - 15 Sep	LOT
08 Sep - 22 Sep	LOT
03 Sep - 10 Sep	Air China
04 Sep - 17 Sep	Air China
09 Sep - 15 Sep	LOT
09 Sep - 16 Sep	LOT
30 Sep - 05 Oct	Etihad Airways
02 Sep - 23 Sep	Etihad Airways
22 Sep - 25 Sep	Emirates
23 Sep - 21 Oct	Etihad Airways
17 Sep - 22 Oct	Etihad Airways
23 Sep - 04 Oct	LOT
24 Sep - 01 Oct	KLM
24 Sep - 03 Oct	KLM
24 Sep - 04 Oct	KLM
18 Sep - 02 Oct	Air France
23 Sep - 05 Oct	Air France
09 Sep - 02 Oct	Air France

Also check the deals for one-way flights from Seoul to Lisbon 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 Seoul to Lisbon in September from $728

Return flights