AirHint found the following cheapest one-way flights from Chicago (ORD) to Sydney (SYD) in September 2025 (see full year).
One-Way flights
| 03 Sep | Spirit Airlines | ||
| 15 Sep | Alaska Airlines | ||
| 02 Sep | Spirit Airlines | ||
| 25 Sep | Alaska Airlines | ||
| 09 Sep | Fiji Airways | ||
| 12 Sep | Fiji Airways |
Also check the deals for return flights from Chicago to Sydney in September.
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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