Cheapest return flights from Lisbon to Keflavik in September from $221

Best time to book flights for Lisbon (LIS) to Keflavik (KEF) flights at AirHint

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

Return flights

23 Sep - 28 Sep easyJet
20 Sep - 28 Sep easyJet
05 Sep - 15 Sep Fly Play direct
10 Sep - 16 Sep Ryanair
10 Sep - 14 Sep Ryanair
08 Sep - 22 Sep Fly Play direct
09 Sep - 23 Sep easyJet
07 Sep - 16 Sep Ryanair
11 Sep - 15 Sep Ryanair
08 Sep - 16 Sep Ryanair
25 Sep - 06 Oct Ryanair
22 Sep - 02 Oct Ryanair
26 Sep - 06 Oct Fly Play direct
29 Sep - 03 Oct easyJet
28 Sep - 12 Oct easyJet
28 Sep - 03 Oct Iberia
28 Sep - 12 Oct Icelandair direct
29 Sep - 03 Oct Fly Play direct

Also check the deals for one-way flights from Lisbon 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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