AirHint found the following cheapest return flights from Lisbon (LIS) to Keflavik (KEF) in May 2026 (see full year).
Return flights
| 11 May - 15 May | Fly Play | direct | |
| 10 May - 15 May | Iberia | ||
| 25 May - 31 May | TAP | ||
| 17 May - 31 May | TAP |
Also check the deals for one-way flights from Lisbon 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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