Cheapest return flights from Seattle to Sydney in December from 1115€

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

Return flights

10 Dec - 18 Dec Delta
22 Dec - 29 Dec Air Canada
16 Dec - 07 Jan Alaska Airlines
16 Dec - 30 Dec Air Canada
27 Dec - 11 Jan United
21 Dec - 01 Jan Hawaiian Airlines
11 Dec - 02 Jan United
26 Dec - 04 Jan Air Canada
14 Dec - 09 Jan Delta
21 Dec - 02 Jan Hawaiian Airlines

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

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