AirHint found the following cheapest return flights from Seattle (SEA) to Amsterdam (AMS) in September 2026 (see full year).

Return flights

01 Sep - 11 Sep	Scandinavian Airlines
01 Sep - 10 Sep	Scandinavian Airlines
18 Sep - 06 Oct	Scandinavian Airlines
23 Sep - 30 Sep	Icelandair
24 Sep - 17 Oct	Turkish Airlines
25 Sep - 17 Oct	Icelandair
24 Sep - 03 Oct	Icelandair
01 Sep - 10 Sep	Delta	direct
01 Sep - 11 Sep	Delta	direct
24 Sep - 03 Oct	Delta	direct
24 Sep - 17 Oct	Delta	direct
25 Sep - 17 Oct	Delta	direct

Also check the deals for one-way flights from Seattle to Amsterdam 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.

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Cheapest return flights from Seattle to Amsterdam in September from 540€

Return flights