Cheapest return flights from Seattle to Copenhagen in September from $446

AirHint found the following cheapest return flights from Seattle (SEA) to Copenhagen (CPH) in September 2025 (see full year).

Return flights

30 Sep - 07 Oct Icelandair
21 Sep - 14 Oct Icelandair
09 Sep - 16 Sep Icelandair
15 Sep - 22 Sep Icelandair
21 Sep - 28 Sep Icelandair
03 Sep - 10 Sep Icelandair
06 Sep - 13 Sep Icelandair
24 Sep - 01 Oct Icelandair
27 Sep - 04 Oct Icelandair
12 Sep - 19 Sep Icelandair
18 Sep - 25 Sep Icelandair

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