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$491+ 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 3/10. Fares are subject to change and may not be available on all flights or dates of travel.
ORD — SYD
Mar 14 — Mar 211
Sat 3/14
Sat 3/21
1 adult, Economy
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Cheap 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 February 12, 2026.

This oojo deal was found by Cheapflights users on 2/10. 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.
Tue 3/34:13 pm
STL
-
SYD
2 stops35h 37m
Qantas Airways
Tue 3/1011:20 am
SYD
-
STL
1 stop28h 38m
Qantas Airways
Deal found 2/10$898
This oojo deal was found by Cheapflights users on 2/11. 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.
Thu 3/194:13 pm
STL
-
SYD
2 stops36h 37m
Qantas Airways
Wed 3/2511:20 am
SYD
-
STL
1 stop28h 38m
Qantas Airways
Deal found 2/11$899
This oojo deal was found by Cheapflights users on 2/11. 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.
Thu 2/126:38 am
STL
-
SYD
1 stop33h 22m
Qantas Airways
Thu 2/195:50 pm
SYD
-
STL
2 stops40h 23m
Qantas Airways
Deal found 2/11$908
This Kiwi.com deal was found by Cheapflights users on 2/9. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 4/67:45 pm
ORD
-
MEL
1 stop44h 00m
Multiple Airlines
Sun 4/191:30 pm
MEL
-
ORD
2 stops31h 20m
Multiple Airlines
Deal found 2/9$928
This Kiwi.com deal was found by Cheapflights users on 2/9. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/77:21 pm
ORD
-
BNE
1 stop42h 39m
Multiple Airlines
Mon 5/2511:55 am
BNE
-
ORD
2 stops33h 51m
Multiple Airlines
Deal found 2/9$933
This oojo deal was found by Cheapflights users on 2/9. 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 2/112:15 pm
ORD
-
SYD
1 stop25h 45m
Qantas Airways
Thu 2/267:05 am
SYD
-
ORD
2 stops26h 32m
Qantas Airways
Deal found 2/9$941
This oojo deal was found by Cheapflights users on 2/10. 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.
Tue 2/106:40 pm
ORD
-
SYD
1 stop21h 20m
Qantas Airways
Tue 3/37:05 am
SYD
-
ORD
2 stops24h 48m
Qantas Airways
Deal found 2/10$942
This Ovago deal was found by Cheapflights users on 2/9. 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 Ovago is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 2/136:38 am
STL
-
SYD
1 stop33h 22m
Qantas Airways
Sun 2/157:15 pm
SYD
-
STL
2 stops45h 44m
Qantas Airways
Deal found 2/9$943
This oojo deal was found by Cheapflights users on 2/10. 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.
Mon 2/168:45 pm
ORD
-
MEL
1 stop43h 45m
Qantas Airways
Tue 2/246:45 am
MEL
-
ORD
2 stops25h 08m
Qantas Airways
Deal found 2/10$944
This oojo deal was found by Cheapflights users on 2/10. 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 2/116:49 pm
ORD
-
SYD
1 stop21h 11m
Qantas Airways
Fri 2/277:05 am
SYD
-
ORD
2 stops26h 32m
Qantas Airways
Deal found 2/10$944
This oojo deal was found by Cheapflights users on 2/9. 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.
Thu 2/264:45 pm
ORD
-
SYD
1 stop21h 40m
Qantas Airways
Tue 3/37:05 am
SYD
-
ORD
2 stops24h 48m
Qantas Airways
Deal found 2/9$948
This oojo deal was found by Cheapflights users on 2/11. 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 2/182:33 pm
ORD
-
BNE
1 stop22h 27m
Qantas Airways
Wed 2/256:30 pm
BNE
-
ORD
2 stops36h 23m
Qantas Airways
Deal found 2/11$948

Find flight deals from Illinois to Australia

Keep the following information in mind while searching for Illinois to Australia flight deals. Data was last updated February 12, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$898
(oojo)

One-way from

$491
(Kiwi.com)

Popular in

December

Cheapest in

October

Average price

$1,097
Provider with most accurate pricing for Chicago (CHI)-Sydney Kingsford Smith flight deals.
Search Deals
Provider most trusted by Cheapflights users for Chicago (CHI)-Sydney Kingsford Smith flights.
Search Deals
From Illinois to Australia
Search Deals
One-way flight from Illinois to Australia
Search Deals
Highest demand for flights based on searches. 9% potential increase in price ($128 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 1% potential price decrease ($25 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in February 2026
Search Deals

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 February 12, 2026.
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

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Fri 2/27

6:38 am-9:00 am

1 stop33h 22m

Sydney Kingsford Smith

Mon 3/9

5:50 pm-3:28 pm

2 stops37h 38m

$908

St. LouisBrisbane

STL - BNE

STLBNE

Lambert-St Louis

Sun 3/22

4:05 pm-7:45 am

2 stops48h 40m

Brisbane

Wed 4/29

10:00 am-4:56 pm

2 stops21h 56m

$961

ChicagoBrisbane

ORD - BNE

ORDBNE

Chicago O'Hare Intl

Wed 4/15

8:42 am-7:05 am

2 stops31h 23m

Brisbane

Sun 4/19

10:00 am-2:43 pm

1 stop19h 43m

$964

ChicagoBrisbane

ORD - BNE

ORDBNE

Chicago O'Hare Intl

Tue 3/3

4:45 pm-7:30 am

2 stops46h 45m

Brisbane

Tue 3/10

7:40 pm-11:47 pm

1 stop19h 07m

$969

ChicagoBrisbane

ORD - BNE

ORDBNE

Chicago O'Hare Intl

Mon 5/4

8:41 am-7:05 am

2 stops31h 24m

Brisbane

Thu 5/14

10:00 am-5:01 pm

2 stops22h 01m

$1,007

ChicagoBrisbane

ORD - BNE

ORDBNE

Chicago O'Hare Intl

Thu 5/7

6:03 pm-7:05 am

2 stops46h 02m

Brisbane

Sun 5/24

10:00 am-2:45 pm

1 stop19h 45m

$1,009

ChicagoBrisbane

ORD - BNE

ORDBNE

Chicago O'Hare Intl

Fri 3/20

3:35 pm-7:45 am

1 stop25h 10m

Brisbane

Sun 4/19

10:00 am-2:43 pm

1 stop19h 43m

$1,010

ChicagoBrisbane

ORD - BNE

ORDBNE

Chicago O'Hare Intl

Fri 3/20

3:35 pm-7:45 am

1 stop25h 10m

Brisbane

Wed 4/29

10:00 am-7:58 pm

1 stop24h 58m

$1,010

St. LouisBrisbane

STL - BNE

STLBNE

Lambert-St Louis

Tue 3/10

10:05 am-7:45 am

2 stops30h 40m

Brisbane

Wed 3/18

9:45 am-4:49 pm

2 stops22h 04m

$1,033

St. LouisBrisbane

STL - BNE

STLBNE

Lambert-St Louis

Tue 3/10

6:08 pm-5:10 pm

2 stops32h 02m

Brisbane

Wed 3/18

7:40 pm-11:58 pm

1 stop19h 18m

$1,034

Flights are sorted by cheapest round-trip flights first.

Deals found on 2/12

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, August is the cheapest month in which you can book a flight from Illinois to Australia (average of $198). Flying from Illinois to Australia in June is currently the most expensive (average of $833). 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.

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 26h 40m. Illinois and Australia are separated by a distance of 9660 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?

    $229 is the cheapest one-way deal found within the past few days, from United Airlines. You may also be able to find cheap deals on ANA and American Airlines, with prices starting from $304 and $395, 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, August is the cheapest month in which you can book a flight from Illinois to Australia (average of $198). Flying from Illinois to Australia in June is currently the most expensive (average of $833). 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

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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 February 12, 2026.
AirlineCheapestAverageFlexibilityOn-time
Qantas AirwaysCheapest$675Average$1,576FlexibilityNo cancel feeOn-time74%
American AirlinesCheapest$698Average$1,162FlexibilityNo cancel feeOn-time71%
Fiji AirwaysCheapest$795Average$1,303FlexibilityNo cancel feeOn-time74%
United AirlinesCheapest$870Average$1,513FlexibilityNo cancel feeOn-time69%
Air CanadaCheapest$872Average$1,226FlexibilityNo cancel feeOn-time67%
DeltaCheapest$935Average$1,034FlexibilityNo cancel feeOn-timeN/A
ANACheapest$1,177Average$1,259FlexibilityNo cancel feeOn-time80%
Air New ZealandCheapest$1,217Average$1,489FlexibilityNo cancel feeOn-time78%
Qatar AirwaysCheapest$1,229Average$2,092FlexibilityNo cancel feeOn-time68%
Cathay PacificCheapest$1,470Average$1,786FlexibilityNo cancel feeOn-time72%

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