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Cheap flights from Illinois to Sydney from $721

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 2/5. Fares are subject to change and may not be available on all flights or dates of travel.
ORD — SYD
7 May — 14 May1
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 7 April 2026.

Mon 18/508:30
ORD
-
SYD
3 stops36h 35m
Multiple Airlines
Mon 25/513:15
SYD
-
ORD
3 stops48h 58m
Multiple Airlines
Deal found 3/4$1,616
Mon 18/508:30
ORD
-
SYD
3 stops36h 35m
Multiple Airlines
Mon 1/613:15
SYD
-
ORD
2 stops31h 49m
Multiple Airlines
Deal found 3/4$1,638
Sun 17/507:15
ORD
-
SYD
2 stops37h 35m
Multiple Airlines
Sun 24/513:15
SYD
-
ORD
2 stops31h 44m
Multiple Airlines
Deal found 3/4$1,647
Sun 24/515:40
ORD
-
SYD
1 stop24h 40m
Air Canada
Sun 31/509:20
SYD
-
ORD
1 stop20h 25m
Air Canada
Deal found 2/4$1,648
Sat 4/715:40
ORD
-
SYD
1 stop24h 40m
Air Canada
Sun 26/709:20
SYD
-
ORD
1 stop20h 21m
Air Canada
Deal found 6/4$1,654
Wed 4/1115:40
ORD
-
SYD
1 stop24h 55m
Air Canada
Sun 15/1111:20
SYD
-
ORD
1 stop20h 21m
Air Canada
Deal found 3/4$1,655
Sun 1/1115:40
ORD
-
SYD
1 stop24h 55m
Air Canada
Sat 14/1111:20
SYD
-
ORD
1 stop20h 21m
Air Canada
Deal found 4/4$1,657
Mon 8/615:40
ORD
-
SYD
1 stop24h 40m
Air Canada
Sat 18/709:20
SYD
-
ORD
2 stops25h 45m
Air Canada
Deal found 2/4$1,658
Thu 20/805:10
STL
-
SYD
2 stops35h 10m
Air Canada
Fri 11/909:20
SYD
-
STL
2 stops42h 20m
Air Canada
Deal found 2/4$1,667
Tue 13/1012:10
STL
-
SYD
2 stops28h 10m
Air Canada
Fri 13/1111:20
SYD
-
STL
2 stops45h 10m
Air Canada
Deal found 6/4$1,671
Tue 13/1008:55
STL
-
SYD
2 stops31h 25m
Air Canada
Wed 18/1111:20
SYD
-
STL
2 stops45h 10m
Air Canada
Deal found 2/4$1,677
Wed 10/608:40
STL
-
SYD
2 stops31h 40m
Air Canada
Sat 11/709:20
SYD
-
STL
2 stops43h 42m
Air Canada
Deal found 4/4$1,678

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 7 April 2026.

Round-trip from

$1,616

One-way from

$721

Popular in

July

Cheapest in

February

Average price

$2,099
18/5-25/5
  • 18/5-25/5
  • 6 total stops
  • 85h 33m total
  • Illinois to Sydney
Search Deals
2/5
  • 2/5
  • 2 total stops
  • 34h 27m total
  • Illinois to Sydney
Search Deals
Highest demand for flights based on searches. 4% potential increase in price ($132 potential increase over avg. return price).
Search Deals
Cheapest flight prices on average. 1% potential price decrease ($42 potential savings vs. average return price).
Search Deals
Average for round-trip flights in April 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 7 April 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

Sun 17/5

16:44-07:00

2 stops23h 16m

Sydney Kingsford Smith

Sun 24/5

10:20-18:17

1 stop22h 57m

$2,147

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Mon 4/5

19:06-06:55

1 stop20h 49m

Sydney Kingsford Smith

Mon 18/5

10:20-18:22

1 stop23h 02m

$2,148

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Tue 21/7

13:38-06:55

2 stops26h 17m

Sydney Kingsford Smith

Wed 5/8

10:20-16:33

2 stops21h 13m

$2,154

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Mon 4/5

14:35-06:55

2 stops25h 20m

Sydney Kingsford Smith

Mon 11/5

10:20-18:22

1 stop23h 02m

$2,154

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Mon 20/7

19:23-06:55

1 stop20h 32m

Sydney Kingsford Smith

Tue 28/7

09:30-16:33

2 stops22h 03m

$2,155

PeoriaSydney

PIA - SYD

PIASYD

Greater Peoria

Sat 11/7

10:45-06:55

2 stops29h 10m

Sydney Kingsford Smith

Fri 14/8

10:20-16:56

2 stops21h 36m

$2,255

PeoriaSydney

PIA - SYD

PIASYD

Greater Peoria

Mon 14/9

10:35-07:00

2 stops29h 25m

Sydney Kingsford Smith

Mon 28/9

10:20-00:19

2 stops28h 59m

$2,255

ChicagoSydney

ORD - SYD

ORDSYD

Chicago O'Hare Intl

Mon 17/8

18:45-07:05

1 stop21h 20m

Sydney Kingsford Smith

Sat 5/9

17:50-00:12

1 stop21h 22m

$2,314

ChicagoSydney

MDW - SYD

MDWSYD

Chicago Midway

Mon 29/6

12:45-06:50

2 stops27h 05m

Sydney Kingsford Smith

Mon 13/7

09:15-18:18

2 stops24h 03m

$2,327

ChicagoSydney

MDW - SYD

MDWSYD

Chicago Midway

Tue 1/9

13:00-06:50

2 stops26h 50m

Sydney Kingsford Smith

Tue 8/9

09:15-18:05

2 stops23h 50m

$2,327

Flights are sorted by cheapest return flights first.

Deals found on 6/4

Showing 1-10 of 47 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, August is the cheapest month in which you can book a flight from Illinois to Sydney (average of $286). Flying from Illinois to Sydney in July is currently the most expensive (average of $1,795). 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?

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 23h 16m. United Airlines provides one of the quickest options available for as low as $2,147. 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, August is the cheapest month in which you can book a flight from Illinois to Sydney (average of $286). Flying from Illinois to Sydney in July is currently the most expensive (average of $1,795). 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
Terrigal
Katoomba
Lithgow
Cronulla
Manly
Bondi Beach
Coogee
Leura
Randwick

Browse thousands of different options on Cheapflights for your next trip

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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 7 April 2026.
AirlineCheapestAverageFlexibilityOn-time
Qantas AirwaysCheapest$1,956Average$2,352FlexibilityNo 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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