Cheapest return flights from Lisbon to Keflavik in September from $232

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

24 Sep - 01 Oct Ryanair
24 Sep - 28 Sep Ryanair
12 Sep - 22 Sep Fly Play direct
12 Sep - 15 Sep Fly Play direct
25 Sep - 29 Sep Ryanair
16 Sep - 22 Sep Ryanair
05 Sep - 09 Sep Ryanair
05 Sep - 07 Sep Ryanair
20 Sep - 27 Sep easyJet
11 Sep - 14 Sep Ryanair
02 Sep - 05 Sep easyJet

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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