Cheapest return flights from Seattle to Helsinki in September from $866

Best time to book flights for Seattle (SEA) to Helsinki (HEL) flights at AirHint

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

Return flights

16 Sep - 30 Sep Turkish Airlines
11 Sep - 18 Sep Icelandair

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