Cheapest return flights from Keflavik to Lisbon in September from $368

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

Return flights

22 Sep - 25 Sep KLM
17 Sep - 20 Sep Fly Play
18 Sep - 21 Sep Wizz Air Malta
26 Sep - 29 Sep Fly Play direct
14 Sep - 17 Sep Wizz Air Malta
09 Sep - 13 Sep Fly Play
11 Sep - 15 Sep Wizz Air Malta
15 Sep - 18 Sep Fly Play
11 Sep - 14 Sep Wizz Air Malta
19 Sep - 28 Sep Fly Play

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