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$504+ Cheap flights from Illinois to Australia

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 11/8. Fares are subject to change and may not be available on all flights or dates of travel.
ORD — SYD
Oct 25 — Nov 11
Sat 10/25
Sat 11/1
1 adult, Economy
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Cheap flight deals from Illinois to Australia

Keep the following information in mind while searching for Illinois to Australia flight deals. Data was last updated September 25, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$955
(FlightHub)

One-way from

$504
(Trip.com)

Popular in

December

Cheapest in

August

Average price

$999
Provider with most accurate pricing for Chicago (CHI)-Sydney Kingsford Smith flight deals.
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Provider most trusted by Cheapflights users for Chicago (CHI)-Sydney Kingsford Smith flights.
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From Illinois to Australia
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One-way flight from Illinois to Australia
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Highest demand for flights based on searches. 16% potential increase in price ($187 potential increase over avg. RT price).
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Cheapest flight prices on average. 3% potential price decrease ($37 potential savings vs. average RT price).
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Average for round-trip flights in September 2025
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Find flight deals from Illinois to Australia

Cheapest flights from Illinois to Australia
Explore the most affordable flight options available from Illinois to Australia. Find the lowest fares from popular airlines and budget airlines, with prices last updated on September 25, 2025.

This Trip.com deal was found by Cheapflights users on 9/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/86:15 amMDW - SYD
2 stops31h 45mMultiple Airlines
Sat 11/1512:10 pmSYD - MDW
2 stops26h 25mMultiple Airlines
Deal found 9/24$993
This oojo deal was found by Cheapflights users on 9/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/296:39 amSTL - SYD
1 stop34h 21mQantas Airways
Thu 11/135:50 pmSYD - STL
2 stops38h 39mQantas Airways
Deal found 9/24$997
This Trip.com deal was found by Cheapflights users on 9/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/38:00 amMDW - SYD
2 stops30h 25mMultiple Airlines
Wed 12/102:05 pmSYD - MDW
2 stops24h 27mMultiple Airlines
Deal found 9/24$998
This Justfly.com deal was found by Cheapflights users on 9/25. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Justfly.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/296:39 amSTL - SYD
1 stop34h 21mQantas Airways
Sat 11/157:15 pmSYD - STL
2 stops38h 53mQantas Airways
Deal found 9/25$1,002
This Trip.com deal was found by Cheapflights users on 9/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/86:00 amORD - SYD
2 stops32h 00mMultiple Airlines
Sat 11/1511:50 amSYD - ORD
2 stops28h 39mMultiple Airlines
Deal found 9/24$1,003
This oojo deal was found by Cheapflights users on 9/25. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 11/93:59 pmSTL - SYD
2 stops32h 41mQantas Airways
Sun 11/165:45 pmSYD - STL
1 stop22h 57mQantas Airways
Deal found 9/25$1,009
This Trip.com deal was found by Cheapflights users on 9/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/36:10 amORD - SYD
2 stops32h 15mMultiple Airlines
Wed 12/102:05 pmSYD - ORD
2 stops26h 06mMultiple Airlines
Deal found 9/24$1,025
This Trip.com deal was found by Cheapflights users on 9/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 11/76:30 amORD - BNE
2 stops35h 50mMultiple Airlines
Fri 11/1411:20 amBNE - ORD
2 stops27h 40mMultiple Airlines
Deal found 9/24$1,048
This Trip.com deal was found by Cheapflights users on 9/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/86:30 amORD - BNE
2 stops35h 40mMultiple Airlines
Sat 11/1511:25 amBNE - ORD
2 stops27h 35mMultiple Airlines
Deal found 9/24$1,050
This Alaska Airlines deal was found by Cheapflights users on 9/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 11/1210:00 amORD - SYD
2 stops40h 45mAlaska Airlines
Tue 11/189:40 pmSYD - ORD
2 stops35h 50mAlaska Airlines
Deal found 9/24$1,058
This Alaska Airlines deal was found by Cheapflights users on 9/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/2110:05 amORD - SYD
2 stops41h 40mAlaska Airlines
Tue 10/289:40 pmSYD - ORD
2 stops40h 00mAlaska Airlines
Deal found 9/24$1,069
This Alaska Airlines deal was found by Cheapflights users on 9/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/2110:05 amORD - SYD
2 stops41h 40mAlaska Airlines
Fri 10/319:40 pmSYD - ORD
2 stops42h 44mAlaska Airlines
Deal found 9/24$1,082

Cheapflights Fare Finder

 
Customize your flight search to find flights from Illinois to Australia that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated September 25, 2025.
Use the filters below to find and compare flights from Illinois to Australia that are best for you.

Fly from

Illinois

Fly to

Australia

Route

Depart

Return

Price

ChicagoSydney

MDW - SYD

MDWSYD

Chicago Midway

Sat 11/8

6:15 am-7:00 am

2 stops31h 45m

Sydney Kingsford Smith

Sat 11/15

12:10 pm-9:35 pm

2 stops26h 25m

$993

ChicagoSydney

MDW - SYD

MDWSYD

Chicago Midway

Wed 12/3

8:00 am-7:25 am

2 stops30h 25m

Sydney Kingsford Smith

Wed 12/10

2:05 pm-9:32 pm

2 stops24h 27m

$998

ChicagoBrisbane

ORD - BNE

ORDBNE

Chicago O'Hare Intl

Fri 11/7

6:30 am-10:20 am

2 stops35h 50m

Brisbane

Fri 11/14

11:20 am-11:00 pm

2 stops27h 40m

$1,048

ChicagoSydney

ORD - SYD

ORDSYD

Chicago O'Hare Intl

Sun 11/9

6:00 am-7:45 pm

2 stops44h 45m

Sydney Kingsford Smith

Tue 11/18

9:40 pm-9:40 pm

2 stops41h 00m

$1,115

ChicagoSydney

ORD - SYD

ORDSYD

Chicago O'Hare Intl

Fri 10/24

5:59 pm-7:45 pm

2 stops33h 46m

Sydney Kingsford Smith

Sun 11/2

9:40 pm-6:22 am

2 stops49h 42m

$1,123

ChicagoSydney

ORD - SYD

ORDSYD

Chicago O'Hare Intl

Sun 11/9

6:00 am-7:45 pm

2 stops44h 45m

Sydney Kingsford Smith

Fri 11/21

9:40 pm-6:28 am

2 stops25h 48m

$1,164

ChicagoSydney

ORD - SYD

ORDSYD

Chicago O'Hare Intl

Tue 2/10

3:22 pm-12:30 pm

2 stops28h 08m

Sydney Kingsford Smith

Tue 2/24

2:10 pm-7:18 pm

2 stops22h 08m

$1,219

St. LouisMelbourne

STL - AVV

STLAVV

Lambert-St Louis

Sun 2/8

4:05 pm-2:10 pm

3 stops53h 05m

Melbourne Avalon

Sat 6/13

8:55 pm-3:16 pm

3 stops57h 21m

$1,241

St. LouisMelbourne

STL - MEL

STLMEL

Lambert-St Louis

Sat 2/7

5:54 pm-12:45 pm

2 stops25h 51m

Melbourne

Thu 2/26

2:30 pm-10:24 pm

2 stops24h 54m

$1,248

ChicagoBrisbane

ORD - BNE

ORDBNE

Chicago O'Hare Intl

Wed 10/22

2:20 pm-7:45 am

2 stops26h 25m

Brisbane

Wed 11/12

11:10 am-7:56 pm

2 stops24h 46m

$1,269

Flights are sorted by cheapest round-trip flights first.

Deals found on 9/24

Showing 1-10 of 60 results
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Best time to book a flight from Illinois to Australia

Have a flexible travel schedule? Discover the best time to fly to Australia from Illinois with our price prediction graph.
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Cheapflights Insights

Everything you need to know about your flight from Illinois to Australia

What is the cheapest month to book a flight from Illinois to Australia?

Currently, March is the cheapest month in which you can book a flight from Illinois to Australia (average of $1,032). Flying from Illinois to Australia in December is currently the most expensive (average of $1,626). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

What is the cheapest time of day to fly from IL to AU?

Find hourly flight availability from Illinois to Australia. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated September 25, 2025.

Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Illinois to Australia as you normally would.

Related info for your journey

Find useful and relevant information for your journey from Illinois to Australia. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • How long is the flight from Illinois to Australia?

    Departing from Illinois to Australia will take you 25h 51m. Illinois and Australia are separated by a distance of 9479 mi. When browsing for deals, the options you’ll see will be for both nonstop flights and flights with stops.

  • What are the cheapest airlines to fly from Illinois to Australia one-way?

    $855 is the cheapest one-way deal found within the past few days, from Qantas Airways. You may also be able to find cheap deals on Delta and American Airlines, with prices starting from $917 and $933, respectively.

  • Can I find deals for flights from Illinois to Australia that include hotel bookings?

    Yes. In addition to deals on Illinois to Australia flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Illinois to Australia?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Illinois to Australia.

  • Can I find deals for business class flights from Illinois to Australia?

    Yes. Cheapflights offers flight deals from Illinois to Australia by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

  • What is the cheapest month to book a flight from Illinois to Australia?

    Currently, March is the cheapest month in which you can book a flight from Illinois to Australia (average of $1,032). Flying from Illinois to Australia in December is currently the most expensive (average of $1,626). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

Browse thousands of different options on Cheapflights for your next trip

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Alternative routes for Illinois to Australia

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Top 10 airlines flying from Illinois to Australia

Discover the top 10 airlines that operate flights from Illinois to Australia. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated September 25, 2025.
AirlineCheapestAverageFlexibilityOn-time
Qantas AirwaysCheapest$647Average$1,342FlexibilityNo cancel feeOn-time74%
ANACheapest$679Average$1,186FlexibilityNo cancel feeOn-time80%
American AirlinesCheapest$679Average$1,295FlexibilityNo cancel feeOn-time71%
Fiji AirwaysCheapest$772Average$1,426FlexibilityNo cancel feeOn-time74%
DeltaCheapest$846Average$1,018FlexibilityNo cancel feeOn-timeN/A
Air CanadaCheapest$872Average$1,307FlexibilityNo cancel feeOn-time67%
United AirlinesCheapest$876Average$1,372FlexibilityNo cancel feeOn-time69%
Qatar AirwaysCheapest$1,229Average$1,775FlexibilityNo cancel feeOn-time68%
Air New ZealandCheapest$1,264Average$1,511FlexibilityNo cancel feeOn-time78%
Cathay PacificCheapest$1,470Average$2,048FlexibilityNo cancel feeOn-time72%

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