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

Return flights

23 Sep - 03 Oct	easyJet
26 Sep - 03 Oct	easyJet
21 Sep - 03 Oct	easyJet
28 Sep - 03 Oct	easyJet
27 Sep - 03 Oct	easyJet
24 Sep - 03 Oct	Wizz Air Malta
27 Sep - 10 Oct	easyJet
29 Sep - 03 Oct	Vueling Airlines
28 Sep - 06 Oct	easyJet
17 Sep - 17 Oct	Icelandair	direct
17 Sep - 24 Sep	Icelandair	direct
10 Sep - 24 Sep	Icelandair	direct
01 Sep - 09 Sep	Wizz Air Malta
13 Sep - 16 Sep	Wizz Air Malta
26 Sep - 29 Sep	easyJet
13 Sep - 23 Sep	Wizz Air Malta
01 Sep - 10 Sep	Wizz Air Malta
03 Sep - 09 Sep	Norwegian
13 Sep - 18 Sep	Wizz Air Malta
02 Sep - 10 Sep	Wizz Air Malta

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

Book a cheap hotel in Keflavik

Cheap car rent in Keflavik

Cheapest return flights from London to Keflavik in September from 114€

Return flights