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

Return flights

09 Sep - 19 Sep	Air Canada
29 Sep - 06 Oct	Air France
08 Sep - 15 Sep	Air France
30 Sep - 06 Oct	Delta
09 Sep - 16 Sep	Air France
11 Sep - 19 Sep	Air Canada
10 Sep - 19 Sep	United
15 Sep - 22 Sep	Delta
10 Sep - 17 Sep	United
15 Sep - 19 Sep	Air France
08 Sep - 12 Sep	Air France
11 Sep - 15 Sep	Air Canada
28 Sep - 06 Oct	Frontier Airlines
22 Sep - 01 Oct	Frontier Airlines
29 Sep - 05 Oct	Spirit Airlines
28 Sep - 05 Oct	Frontier Airlines
25 Sep - 05 Oct	Frontier Airlines
25 Sep - 06 Oct	Spirit Airlines
28 Sep - 03 Oct	Air Canada
26 Sep - 04 Oct	Frontier Airlines

Also check the deals for one-way flights from New York to Keflavik in September.

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 New York to Keflavik in September from 331€

Return flights