Cheapest return flights from London to Keflavik in September from $171

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

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

Return flights

27 Sep - 02 Oct Icelandair direct
25 Sep - 05 Oct Icelandair direct
18 Sep - 21 Sep Icelandair direct
18 Sep - 24 Sep Icelandair direct
04 Sep - 16 Sep Icelandair direct
09 Sep - 13 Sep Icelandair direct
13 Sep - 16 Sep Icelandair direct
10 Sep - 16 Sep Icelandair direct
12 Sep - 23 Sep Icelandair direct
25 Sep - 30 Sep Icelandair direct
06 Sep - 13 Sep Icelandair direct
09 Sep - 16 Sep Icelandair direct
27 Sep - 08 Oct Icelandair direct
26 Sep - 06 Oct Icelandair direct
28 Sep - 02 Oct Icelandair direct
23 Sep - 03 Oct Icelandair direct
24 Sep - 03 Oct Icelandair direct
29 Sep - 07 Oct Icelandair direct
26 Sep - 01 Oct Icelandair direct
28 Sep - 07 Oct Icelandair direct

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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