Cheapest return flights from London to Keflavik in September from $447

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

26 Sep - 30 Sep British Airways
29 Sep - 03 Oct KLM
18 Sep - 02 Oct KLM
24 Sep - 01 Oct KLM
26 Sep - 01 Oct British Airways
10 Sep - 15 Sep KLM
22 Sep - 29 Sep KLM
11 Sep - 18 Sep KLM
22 Sep - 25 Sep KLM
08 Sep - 18 Sep KLM
08 Sep - 19 Sep KLM
25 Sep - 29 Sep KLM
18 Sep - 22 Sep KLM
22 Sep - 28 Sep KLM
30 Sep - 07 Oct SWISS
30 Sep - 06 Oct British Airways
27 Sep - 07 Oct KLM
25 Sep - 05 Oct KLM
27 Sep - 01 Oct KLM
30 Sep - 05 Oct KLM

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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