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

Return flights

03 Dec - 21 Dec	Air New Zealand
01 Dec - 22 Dec	Air New Zealand
08 Dec - 24 Dec	Air New Zealand
01 Dec - 18 Dec	Air New Zealand
09 Dec - 13 Jan	Air Canada
02 Dec - 09 Dec	Alaska Airlines
06 Dec - 22 Dec	Air New Zealand
13 Dec - 08 Jan	Fiji Airways
02 Dec - 09 Dec	Qantas	direct
03 Dec - 21 Dec	United	direct
01 Dec - 22 Dec	United	direct
09 Dec - 13 Jan	United	direct
06 Dec - 22 Dec	United	direct
07 Dec - 06 Jan	Qantas
09 Dec - 05 Jan	United	direct
02 Dec - 05 Jan	United	direct
07 Dec - 05 Jan	United	direct
07 Dec - 06 Jan	United	direct
12 Dec - 01 Jan	Alaska Airlines
12 Dec - 04 Jan	Alaska Airlines

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

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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Cheapest return flights from San Francisco to Sydney in December from $952

Return flights