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

Return flights

14 Sep - 23 Sep	Air China
15 Sep - 22 Sep	Lufthansa
07 Sep - 18 Sep	Air China
16 Sep - 26 Sep	Air China
07 Sep - 14 Sep	Air China
14 Sep - 21 Sep	Air China
07 Sep - 16 Sep	Air China
09 Sep - 12 Sep	Air China
14 Sep - 19 Sep	Air China
09 Sep - 13 Sep	Air China
14 Sep - 02 Oct	Air China
30 Sep - 11 Oct	Finnair
30 Sep - 10 Oct	Finnair
26 Sep - 08 Oct	Finnair
26 Sep - 04 Oct	Finnair
29 Sep - 08 Oct	Finnair
29 Sep - 10 Oct	Finnair
28 Sep - 10 Oct	Etihad Airways
20 Sep - 03 Oct	Etihad Airways
01 Sep - 01 Oct	Air China

Also check the deals for one-way flights from Seoul to London 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 London in September from 584€

Return flights