AirHint found the following cheapest return flights from Portland (PDX) to Keflavik (KEF) in May 2026 (see full year).

Return flights

06 May - 13 May	KLM
05 May - 12 May	KLM
03 May - 10 May	Virgin Atlantic
04 May - 11 May	Virgin Atlantic
02 May - 09 May	Virgin Atlantic
12 May - 19 May	Virgin Atlantic
01 May - 08 May	Virgin Atlantic
10 May - 17 May	Virgin Atlantic
11 May - 18 May	Virgin Atlantic
13 May - 20 May	Delta
26 May - 02 Jun	Icelandair	direct
28 May - 04 Jun	Icelandair	direct
29 May - 05 Jun	Icelandair	direct
31 May - 07 Jun	Icelandair	direct
27 May - 03 Jun	Icelandair	direct
30 May - 06 Jun	Icelandair	direct

Also check the deals for one-way flights from Portland 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.

Book a cheap hotel in Keflavik

Cheap car rent in Keflavik

Cheapest return flights from Portland to Keflavik in May from 420€

Return flights