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Cheap flights from Illinois to Sydney from $889

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 3/11. Fares are subject to change and may not be available on all flights or dates of travel.
ORD — SYD
5 Aug — 12 Aug1
1 adult
1 adult, Economy, 0 bags

Cheap flight deals from Illinois to Sydney

Enter your travel dates to find the best prices.

Cheapest flights from Illinois to Sydney
Explore the most affordable flight options available from Illinois to Sydney. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 6 July 2026.

Sat 19/907:25
MDW
-
SYD
3 stops37h 25m
Multiple Airlines
Tue 29/906:15
SYD
-
MDW
3 stops43h 43m
Multiple Airlines
Deal found 1/7$1,632
Mon 17/815:32
STL
-
SYD
1 stop24h 23m
Qantas Airways
Mon 24/812:00
SYD
-
STL
1 stop21h 05m
Qantas Airways
Deal found 2/7$1,650
Wed 12/806:00
STL
-
SYD
1 stop34h 30m
Qantas Airways
Sun 30/809:10
SYD
-
STL
1 stop28h 49m
Qantas Airways
Deal found 5/7$1,656
Sat 29/811:45
MDW
-
SYD
3 stops33h 05m
Multiple Airlines
Wed 30/913:15
SYD
-
MDW
3 stops36h 43m
Multiple Airlines
Deal found 1/7$1,662
Thu 13/821:27
MDW
-
SYD
3 stops47h 23m
Multiple Airlines
Thu 20/813:15
SYD
-
MDW
3 stops36h 40m
Multiple Airlines
Deal found 1/7$1,675
Sun 16/807:29
ORD
-
SYD
3 stops37h 21m
Multiple Airlines
Mon 24/813:15
SYD
-
ORD
2 stops32h 02m
Multiple Airlines
Deal found 1/7$1,701
Mon 10/816:48
STL
-
SYD
2 stops23h 12m
United Airlines
Mon 17/810:20
SYD
-
STL
1 stop23h 19m
United Airlines
Deal found 1/7$1,708
Tue 18/812:20
PIA
-
SYD
2 stops27h 05m
American Airlines
Tue 25/812:00
SYD
-
PIA
1 stop26h 19m
American Airlines
Deal found 4/7$1,709
Tue 7/713:13
PIA
-
SYD
2 stops26h 42m
United Airlines
Wed 22/709:30
SYD
-
PIA
2 stops28h 50m
United Airlines
Deal found 4/7$1,714
Wed 12/812:52
STL
-
SYD
2 stops26h 58m
Delta
Sun 30/809:15
SYD
-
STL
2 stops29h 43m
Delta
Deal found 5/7$1,715
Sat 22/817:11
STL
-
SYD
1 stop22h 44m
Qantas Airways
Tue 8/917:50
SYD
-
STL
1 stop20h 09m
Qantas Airways
Deal found 3/7$1,719
Wed 12/812:45
STL
-
SYD
1 stop27h 10m
American Airlines
Sun 30/809:10
SYD
-
STL
2 stops23h 55m
American Airlines
Deal found 5/7$1,728

Find flight deals from Illinois to Sydney

Keep the following information in mind while searching for Illinois to Sydney flight deals. Data was last updated 6 July 2026.

Round-trip from

$1,632

One-way from

$889

Popular in

December

Cheapest in

February

Average price

$2,224
19/9-29/9
  • 19/9-29/9
  • 6 total stops
  • 81h 08m total
  • Illinois to Sydney
Search Deals
3/11
  • 3/11
  • 2 total stops
  • 46h 39m total
  • Illinois to Sydney
Search Deals
Highest demand for flights based on searches. 5% potential increase in price ($184 potential increase over avg. return price).
Search Deals
Cheapest flight prices on average. 1% potential price decrease ($56 potential savings vs. average return price).
Search Deals
Average for round-trip flights in July 2026
Search Deals

Cheapflights Fare Finder

 
Customise your flight search to find flights from Illinois to Sydney 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 647,157 searches. Data last updated 6 July 2026.
Use the filters below to find and compare flights from Illinois to Sydney that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest return flight

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Wed 29/7

19:23-06:55

1 stop20h 32m

Sydney Kingsford Smith

Wed 19/8

10:20-18:39

1 stop23h 19m

$1,708

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Mon 10/8

16:48-07:00

2 stops23h 12m

Sydney Kingsford Smith

Mon 17/8

10:20-18:39

1 stop23h 19m

$1,708

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Wed 12/8

08:42-06:55

1 stop31h 13m

Sydney Kingsford Smith

Sun 30/8

10:20-17:59

1 stop22h 39m

$1,708

PeoriaSydney

PIA - SYD

PIASYD

Greater Peoria

Tue 18/8

12:20-06:25

2 stops27h 05m

Sydney Kingsford Smith

Tue 25/8

12:00-23:19

1 stop26h 19m

$1,709

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Sat 22/8

09:00-07:00

2 stops31h 00m

Sydney Kingsford Smith

Tue 8/9

09:30-17:06

2 stops22h 36m

$1,786

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Thu 13/8

08:42-06:55

1 stop31h 13m

Sydney Kingsford Smith

Thu 20/8

10:20-17:59

1 stop22h 39m

$1,852

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Wed 23/9

16:40-07:00

2 stops23h 20m

Sydney Kingsford Smith

Wed 7/10

11:20-18:43

1 stop23h 23m

$1,881

PeoriaSydney

PIA - SYD

PIASYD

Greater Peoria

Tue 18/8

12:20-07:30

3 stops28h 10m

Sydney Kingsford Smith

Tue 25/8

12:00-22:59

2 stops25h 59m

$1,954

ChicagoSydney

ORD - SYD

ORDSYD

Chicago O'Hare Intl

Tue 1/9

15:43-18:50

2 stops36h 07m

Sydney Kingsford Smith

Tue 8/9

20:45-06:20

3 stops24h 35m

$2,224

ChicagoSydney

ORD - SYD

ORDSYD

Chicago O'Hare Intl

Tue 3/11

12:45-19:35

2 stops37h 50m

Sydney Kingsford Smith

Sat 14/11

21:30-18:20

2 stops37h 50m

$2,268

Flights are sorted by cheapest return flights first.

Deals found on 2/7

Showing 1-10 of 49 resultsSorted by cheapest first
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Best time to book a flight from Illinois to Sydney

Have a flexible travel schedule? Discover the best time to fly to Sydney from Illinois with our price prediction graph.
Estimated return 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 Sydney

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

Currently, May is the cheapest month in which you can book a flight from Illinois to Sydney (average of $204). Flying from Illinois to Sydney in October is currently the most expensive (average of $1,197). 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.

How much does it cost for a return flight from Illinois to Sydney?

How far ahead should I book a flight from Illinois to Sydney?

The price you pay for your flight from Illinois to Sydney may vary depending on when you book. For the best chance of a lower fare, look to book 39 days in advance of your trip. Fares are likely to increase a fortnight or so before your departure date.

Related info for your journey

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

  • What airport do you fly into for flights to Sydney from Illinois?

    Located just 7.5 km from the city centre, Sydney Kingsford Smith (SYD) is the airport most travelers will use when flying to Sydney from Illinois.

  • How long is the flight from Illinois to Sydney?

    A quick flight from Illinois to Sydney can take about 20h 32m. United Airlines provides one of the quickest options available for as low as $1,708. The distance between Illinois and Sydney is about 14571 km. Both multi-stop and direct flights can be found to your destination and back.

  • What are the most popular routes from Illinois to Sydney?

    When deciding which route to take from Illinois to Sydney, consider Chicago O'Hare Intl - Sydney Kingsford Smith, Chicago Midway - Sydney Kingsford Smith or Lambert-St Louis - Sydney Kingsford Smith, as they are the most popular.

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

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

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

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

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

    Yes. Cheapflights offers flight deals from Illinois to Sydney 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 Sydney?

    Currently, May is the cheapest month in which you can book a flight from Illinois to Sydney (average of $204). Flying from Illinois to Sydney in October is currently the most expensive (average of $1,197). 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

Travelling to a place near Sydney?

Book flights to Sydney if you plan to visit one of these locations
Parramatta
Wollongong
Penrith
Manly
Katoomba
Lithgow
Cronulla
Terrigal
Randwick
Leura
Bondi Beach
Coogee

Browse thousands of different options on Cheapflights for your next trip

Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.

Top airline flying from Illinois to Sydney

Discover the top airline that operate flights from Illinois to Sydney. 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 647,157 searches. Data last updated 6 July 2026.
AirlineCheapestAverageFlexibilityOn-time
Qantas AirwaysCheapest$2,116Average$2,343FlexibilityNo cancel feeOn-time74%
Search Qantas Airways flights

Fly with Cheapflights

Find the best flight deals on Cheapflights, where travellers can enjoy low prices and a wide availability of flights to their desired destinations.

How does Cheapflights help users find flights from Illinois to Sydney?

When you search for this flight from Illinois to Sydney, Cheapflights searches on 900+ travel sites to save you time finding great flight deals online. Additionally, we offer filter features so you can choose a preferred cabin class or airline, see different price ranges, and much more so you can book the flight for you.

Why should you use Cheapflights to find cheap flight tickets from Illinois to Sydney?

Millions of users choose and trust Cheapflights to book the best flight deals from Illinois to Sydney for free. We help you search and compare prices from hundreds of airlines for the right flight just for you.

Can Cheapflights find flights from Illinois to Sydney with no change fees?

Yes! Cheapflights helps users easily find flights from Illinois to Sydney with no change fees.

Can Cheapflights notify me if prices for flights from Illinois to Sydney become cheaper?

Of course! You can now track prices for flights from Illinois to Sydney and get an alert from Cheapflights when they change. Have a valid email address ready and click the bell icon next to the flight deals above to set up your price alerts.

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