AirHint found the following cheapest return flights from Madrid (MAD) to Keflavik (KEF) in December 2025 (see full year).

Return flights

01 Dec - 09 Dec	easyJet
01 Dec - 06 Dec	easyJet
06 Dec - 09 Dec	easyJet
01 Dec - 05 Dec	easyJet
05 Dec - 09 Dec	easyJet
03 Dec - 12 Dec	Wizz Air Malta
01 Dec - 12 Dec	Wizz Air Malta
01 Dec - 07 Dec	easyJet
12 Dec - 19 Dec	Fly Play	direct
12 Dec - 15 Dec	Fly Play	direct
24 Dec - 01 Jan	easyJet
31 Dec - 07 Jan	Iberia Express
19 Dec - 11 Jan	easyJet
31 Dec - 06 Jan	Iberia Express
22 Dec - 30 Jan	Ryanair
22 Dec - 30 Jan	Fly Play	direct
24 Dec - 06 Jan	Iberia Express
31 Dec - 04 Jan	Iberia Express
29 Dec - 09 Jan	easyJet
31 Dec - 05 Jan	Iberia Express

Also check the deals for one-way flights from Madrid to Keflavik in December.

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 Madrid to Keflavik in December from $171

Return flights