Cheapest return flights from Seattle to Sydney in September from 695€

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

Return flights

08 Sep - 15 Sep Alaska Airlines
09 Sep - 15 Sep United

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