AirHint found the following cheapest return flights from London (LCY) to Copenhagen (CPH) in September 2025 (see full year).

Return flights

03 Sep - 09 Sep	SWISS
02 Sep - 11 Sep	SWISS
02 Sep - 09 Sep	SWISS
03 Sep - 08 Sep	SWISS
04 Sep - 11 Sep	SWISS
04 Sep - 08 Sep	SWISS
25 Sep - 30 Sep	SWISS
20 Sep - 23 Sep	SWISS
20 Sep - 24 Sep	SWISS
20 Sep - 22 Sep	SWISS
20 Sep - 01 Oct	SWISS
29 Sep - 02 Oct	KLM
24 Sep - 02 Oct	KLM
29 Sep - 03 Oct	KLM
25 Sep - 06 Oct	KLM
28 Sep - 02 Oct	KLM
29 Sep - 09 Oct	Lufthansa
29 Sep - 04 Oct	KLM
30 Sep - 02 Oct	KLM
25 Sep - 03 Oct	SWISS

Also check the deals for one-way flights from London to Copenhagen 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 London to Copenhagen in September from $247

Return flights