Cheapest one-way flights from Boston to Helsinki in September from $450

Best time to book flights for Boston (BOS) to Helsinki (HEL) flights at AirHint

AirHint found the following cheapest one-way flights from Boston (BOS) to Helsinki (HEL) in September 2025 (see full year).

One-Way flights

09 Sep Finnair
08 Sep Finnair

Also check the deals for return flights from Boston 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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