AirHint found the following cheapest return flights from Chicago (MDW) to Seoul (ICN) in October 2025 (see full year).

Return flights

16 Oct - 28 Oct	Frontier Airlines
04 Oct - 26 Oct	Frontier Airlines
23 Oct - 30 Oct	Frontier Airlines
15 Oct - 28 Oct	Frontier Airlines
16 Oct - 21 Oct	Frontier Airlines
23 Oct - 01 Nov	Frontier Airlines
30 Oct - 06 Nov	Frontier Airlines
02 Oct - 12 Oct	Frontier Airlines
13 Oct - 27 Oct	Frontier Airlines
23 Oct - 25 Nov	Delta
27 Oct - 31 Oct	Delta
27 Oct - 02 Nov	Delta
25 Oct - 03 Nov	Delta
28 Oct - 02 Nov	Delta
29 Oct - 02 Nov	Delta
30 Oct - 02 Nov	Delta
03 Oct - 09 Oct	Delta
29 Oct - 01 Nov	Delta
22 Oct - 02 Nov	Delta
21 Oct - 29 Oct	Korean Air

Also check the deals for one-way flights from Chicago to Seoul in October.

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 Chicago to Seoul in October from $900

Return flights