Cheapest return flights from Washington to Sydney in September from $1298

Best time to book flights for Washington (IAD) to Sydney (SYD) flights at AirHint

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

Return flights

12 Sep - 28 Sep Air Canada

Also check the deals for one-way flights from Washington 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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