Cheapest return flights from London to Keflavik in September from $465

Best time to book flights for London (LCY) to Keflavik (KEF) flights at AirHint

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

Return flights

24 Sep - 01 Oct KLM
25 Sep - 02 Oct KLM
24 Sep - 08 Oct KLM
18 Sep - 22 Sep KLM
11 Sep - 22 Sep KLM
14 Sep - 18 Sep KLM
14 Sep - 24 Sep KLM
15 Sep - 24 Sep KLM
15 Sep - 19 Sep KLM
22 Sep - 29 Sep KLM
17 Sep - 21 Sep KLM
14 Sep - 21 Sep KLM
03 Sep - 08 Sep KLM
30 Sep - 14 Oct SWISS
24 Sep - 12 Oct KLM
29 Sep - 02 Oct KLM
30 Sep - 07 Oct SWISS
28 Sep - 13 Oct Lufthansa
30 Sep - 05 Oct British Airways
30 Sep - 09 Oct SWISS

Also check the deals for one-way flights from London to Keflavik in September.

Skyscanner

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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