Cheapest return flights from Seattle to Barcelona in September from $489

Best time to book flights for Seattle (SEA) to Barcelona (BCN) flights at AirHint

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

Return flights

10 Sep - 23 Sep Scandinavian Airlines
29 Sep - 06 Oct Icelandair
02 Sep - 09 Sep Icelandair
23 Sep - 02 Oct Air Canada
17 Sep - 27 Sep British Airways
06 Sep - 25 Sep Turkish Airlines
06 Sep - 13 Sep Iberia

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