Cheapest return flights from Seattle to Barcelona in September from 436€

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

Return flights

28 Sep - 11 Oct Scandinavian Airlines
08 Sep - 04 Oct Scandinavian Airlines
16 Sep - 30 Sep Hawaiian Airlines
20 Sep - 30 Sep jetBlue
21 Sep - 29 Sep Hawaiian Airlines
10 Sep - 23 Sep Hawaiian Airlines
14 Sep - 30 Sep Icelandair
29 Sep - 06 Oct Hawaiian Airlines
25 Sep - 18 Oct Icelandair
09 Sep - 04 Oct Icelandair
20 Sep - 26 Sep Icelandair
17 Sep - 24 Sep Icelandair
05 Sep - 13 Sep Icelandair
20 Sep - 11 Oct Icelandair
13 Sep - 20 Sep Hawaiian Airlines
16 Sep - 27 Sep Hawaiian Airlines
30 Sep - 25 Oct WestJet
19 Sep - 11 Oct Scandinavian Airlines
24 Sep - 01 Oct Icelandair
28 Sep - 05 Oct United

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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