AirHint found the following cheapest return flights from London (STN) to Keflavik (KEF) in May 2026 (see full year).

Return flights

08 May - 13 May	easyJet
20 May - 27 May	Ryanair
06 May - 13 May	Ryanair
06 May - 12 May	Ryanair
01 May - 06 May	easyJet
16 May - 19 May	Ryanair
09 May - 16 May	Ryanair
05 May - 09 May	Ryanair
29 May - 03 Jun	easyJet
24 May - 03 Jun	easyJet
06 May - 10 May	Ryanair
26 May - 30 May	Ryanair
31 May - 16 Jun	easyJet
30 May - 02 Jun	Ryanair
28 May - 11 Jun	Ryanair
31 May - 13 Jun	easyJet
25 May - 01 Jun	Ryanair
29 May - 01 Jun	Ryanair
31 May - 14 Jun	easyJet
30 May - 07 Jun	Ryanair

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

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 Keflavik in May from $198

Return flights