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

Return flights

20 Sep - 23 Sep	SWISS
30 Sep - 03 Oct	KLM
26 Sep - 03 Oct	KLM
16 Sep - 01 Oct	KLM
02 Sep - 13 Sep	KLM
05 Sep - 10 Sep	KLM
09 Sep - 13 Sep	KLM
18 Sep - 23 Sep	KLM
19 Sep - 24 Sep	KLM
24 Sep - 29 Sep	KLM
03 Sep - 09 Sep	SWISS
25 Sep - 30 Sep	SWISS
20 Sep - 22 Sep	SWISS
25 Sep - 01 Oct	SWISS
19 Sep - 06 Oct	KLM
29 Sep - 02 Oct	KLM
26 Sep - 01 Oct	KLM
26 Sep - 05 Oct	KLM
27 Sep - 05 Oct	KLM
27 Sep - 03 Oct	KLM

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 210€

Return flights