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Illinois

$595+ Cheap flights from Sydney (SYD) to Illinois

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 8/27. Fares are subject to change and may not be available on all flights or dates of travel.
SYD — ORD
Jul 24 — Jul 311
Fri 7/24
Fri 7/31
1 adult, Economy
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Cheap flight deals from Sydney to Illinois

Cheapest flights from Sydney to Illinois
Explore the most affordable flight options available from Sydney to Illinois. Find the lowest fares from popular airlines and budget airlines, with prices last updated on June 24, 2026.

This Trip.com deal was found by Cheapflights users on 6/23. 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 8/126:05 am
SYD
-
ORD
2 stops39h 12m
Multiple Airlines
Wed 8/199:20 am
ORD
-
SYD
3 stops35h 30m
Multiple Airlines
Deal found 6/23$922
This Trip.com deal was found by Cheapflights users on 6/20. 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.
Mon 8/31:15 pm
SYD
-
MDW
3 stops36h 52m
Multiple Airlines
Mon 8/1711:06 am
MDW
-
SYD
3 stops33h 44m
Multiple Airlines
Deal found 6/20$950
This Trip.com deal was found by Cheapflights users on 6/19. 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.
Mon 7/271:15 pm
SYD
-
ORD
2 stops32h 02m
Multiple Airlines
Mon 8/1010:16 am
ORD
-
SYD
3 stops34h 34m
Multiple Airlines
Deal found 6/19$976
This Trip.com deal was found by Cheapflights users on 6/20. 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.
Mon 8/31:15 pm
SYD
-
ORD
2 stops32h 02m
Multiple Airlines
Mon 8/177:15 am
ORD
-
SYD
3 stops37h 35m
Multiple Airlines
Deal found 6/20$987
This American Airlines deal was found by Cheapflights users on 6/23. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/49:10 am
SYD
-
STL
1 stop29h 49m
American Airlines
Thu 8/203:35 pm
STL
-
SYD
1 stop24h 20m
American Airlines
Deal found 6/23$991
This United Airlines deal was found by Cheapflights users on 6/20. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 7/79:30 am
SYD
-
STL
2 stops26h 13m
United Airlines
Wed 9/24:40 pm
STL
-
SYD
2 stops23h 20m
United Airlines
Deal found 6/20$1,013
This United Airlines deal was found by Cheapflights users on 6/22. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 7/209:30 am
SYD
-
STL
2 stops29h 27m
United Airlines
Mon 7/277:23 pm
STL
-
SYD
1 stop20h 32m
United Airlines
Deal found 6/22$1,014
This Trip.com deal was found by Cheapflights users on 6/22. 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.
Thu 9/31:15 pm
SYD
-
ORD
2 stops32h 02m
Multiple Airlines
Sun 9/201:02 pm
ORD
-
SYD
3 stops31h 48m
Multiple Airlines
Deal found 6/22$1,029
This Trip.com deal was found by Cheapflights users on 6/23. 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 8/71:15 pm
SYD
-
ORD
2 stops32h 02m
Multiple Airlines
Fri 8/1410:16 am
ORD
-
SYD
3 stops34h 34m
Multiple Airlines
Deal found 6/23$1,038
This BusinessClass deal was found by Cheapflights users on 6/22. 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 BusinessClass is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/55:50 pm
SYD
-
ORD
1 stop36h 04m
Qantas Airways
Sun 9/65:05 pm
ORD
-
SYD
1 stop22h 20m
Qantas Airways
Deal found 6/22$1,046
This Delta deal was found by Cheapflights users on 6/20. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 7/69:15 am
SYD
-
STL
2 stops30h 28m
Delta
Sun 8/3011:13 am
STL
-
SYD
2 stops28h 37m
Delta
Deal found 6/20$1,055
This United Airlines deal was found by Cheapflights users on 6/20. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 7/410:20 am
SYD
-
STL
1 stop22h 57m
United Airlines
Mon 8/314:40 pm
STL
-
SYD
2 stops23h 15m
United Airlines
Deal found 6/20$1,062

Find flight deals from Sydney to Illinois

Keep the following information in mind while searching for Sydney to Illinois flight deals. Data was last updated June 24, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$922
(Trip.com)

One-way from

$595
(SmartFares)

Popular in

May

Cheapest in

August

Average price

$1,321
Provider with most accurate pricing for Sydney Kingsford Smith-Chicago (CHI) flight deals.
Search Deals
Provider most trusted by Cheapflights users for Sydney Kingsford Smith-Chicago (CHI) flights.
Search Deals
From Sydney Kingsford Smith to Illinois
Search Deals
One-way flight from Sydney Kingsford Smith to Illinois
Search Deals
Highest demand for flights based on searches. 8% potential increase in price ($115 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 1% potential price decrease ($17 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in June 2026
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Sydney to Illinois 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 June 24, 2026.
Use the filters below to find and compare flights from Sydney to Illinois that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

SydneySt. Louis

SYD - STL

SYDSTL

Sydney Kingsford Smith

Wed 7/8

10:20 am-6:17 pm

1 stop22h 57m

Lambert-St Louis

Wed 9/2

3:13 pm-7:00 am

2 stops24h 47m

$1,013

SydneySt. Louis

SYD - STL

SYDSTL

Sydney Kingsford Smith

Tue 7/7

10:20 am-6:17 pm

1 stop22h 57m

Lambert-St Louis

Wed 9/2

3:13 pm-7:00 am

2 stops24h 47m

$1,013

SydneySt. Louis

SYD - STL

SYDSTL

Sydney Kingsford Smith

Tue 7/7

10:20 am-10:41 pm

2 stops27h 21m

Lambert-St Louis

Sun 8/30

4:40 pm-7:00 am

2 stops23h 20m

$1,013

SydneySt. Louis

SYD - STL

SYDSTL

Sydney Kingsford Smith

Mon 7/20

9:30 am-11:57 pm

2 stops29h 27m

Lambert-St Louis

Mon 7/27

7:23 pm-6:55 am

1 stop20h 32m

$1,014
Quickest round-trip

SydneySt. Louis

SYD - STL

SYDSTL

Sydney Kingsford Smith

Sat 7/4

10:20 am-6:17 pm

1 stop22h 57m

Lambert-St Louis

Tue 9/1

4:40 pm-7:00 am

2 stops23h 20m

$1,062

SydneySt. Louis

SYD - STL

SYDSTL

Sydney Kingsford Smith

Wed 7/8

10:20 am-6:17 pm

1 stop22h 57m

Lambert-St Louis

Thu 9/3

4:40 pm-7:00 am

2 stops23h 20m

$1,062

SydneySt. Louis

SYD - STL

SYDSTL

Sydney Kingsford Smith

Wed 8/12

9:10 am-10:59 pm

1 stop28h 49m

Lambert-St Louis

Sun 8/16

12:45 pm-7:05 am

2 stops27h 20m

$1,075

SydneySt. Louis

SYD - STL

SYDSTL

Sydney Kingsford Smith

Mon 7/6

9:15 am-12:43 am

2 stops30h 28m

Lambert-St Louis

Thu 9/3

2:32 pm-6:50 am

2 stops25h 18m

$1,115

SydneySt. Louis

SYD - STL

SYDSTL

Sydney Kingsford Smith

Wed 8/12

9:10 am-10:59 pm

1 stop28h 49m

Lambert-St Louis

Sun 8/16

6:00 am-7:05 am

1 stop34h 05m

$1,121

SydneyChicago

SYD - ORD

SYDORD

Sydney Kingsford Smith

Wed 11/11

9:55 am-9:34 pm

2 stops28h 39m

Chicago O'Hare Intl

Mon 11/16

1:00 pm-8:45 am

2 stops26h 45m

$1,148

Flights are sorted by cheapest round-trip flights first.

Deals found on 6/21

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

Have a flexible travel schedule? Discover the best time to fly to Illinois from Sydney 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 Sydney to Illinois

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

Currently, December is the cheapest month in which you can book a flight from Sydney to Illinois (average of $468). Flying from Sydney to Illinois in July is currently the most expensive (average of $920). 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 to fly round-trip from Sydney to Illinois?

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

Booking 10 days in advance of your planned departure date is, on average, the best time to get cheap flights from Sydney to Illinois. The general trend is that the closer you book to the departure date, the more expensive your flight will be.

Reviews of airlines servicing Illinois

Get insights into the airlines that provide service to Illinois. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Illinois. Reviews last updated June 24, 2026.
Get a feel of what it's like to fly with Qantas Airways and United Airlines from Sydney to Illinois by reading reviews from past customers. You can also see how each airline compares in terms of entertainment options, comfort, food, crew/service, and boarding process.
Qantas Airways
7.5
Good
1,050 reviews

Overall

7.5

Comfort

7.5

Entertainment

7.2

Crew

8.1

Boarding

7.7

Food

7.0

Reviews

1 / 20
10.0
Excellent

Tania,May 2026

SYD - DFW

The trip was great and the flight attendants were lovely. It was my honeymoon and ai thought I lost my gold brecelet. They searched until they found it and gave us a bottle of champaign to celebrate our honeymoon. They were lovely!
Qantas Airways
7.5
Good
1,050 reviews
Qantas Airways
7.5
Good
1,050 reviews

Overall

7.5

Comfort

7.5

Entertainment

7.2

Crew

8.1

Boarding

7.7

Food

7.0

Reviews

1 / 20
10.0
Excellent

Tania,May 2026

SYD - DFW

The trip was great and the flight attendants were lovely. It was my honeymoon and ai thought I lost my gold brecelet. They searched until they found it and gave us a bottle of champaign to celebrate our honeymoon. They were lovely!
United Airlines
7.4
Good
9,879 reviews
Qantas Airways
7.5
Good
1,050 reviews

Overall

7.5

Comfort

7.5

Entertainment

7.2

Crew

8.1

Boarding

7.7

Food

7.0

Reviews

1 / 20
10.0
Excellent

Tania,May 2026

SYD - DFW

The trip was great and the flight attendants were lovely. It was my honeymoon and ai thought I lost my gold brecelet. They searched until they found it and gave us a bottle of champaign to celebrate our honeymoon. They were lovely!

Related info for your journey

Find useful and relevant information for your journey from Sydney to Illinois. 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 from for flights from Sydney to Illinois?

    Sydney Kingsford Smith (SYD), located 4.6 mi from the city center, is the airport you fly out of when you book flights from Sydney to Illinois.

  • How long is the flight from Sydney to Illinois?

    Airlines like United Airlines, Air New Zealand, and Delta fly from Sydney to Illinois in about 22h 57m. The time it takes to get you to your destination can typically vary by up to 5h 42m. Sydney and Illinois are separated by a distance of 9054 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 Sydney to Illinois one-way?

    $709 is the cheapest one-way deal found within the past few days, from American Airlines. You may also be able to find cheap deals on Air Canada and Qantas Airways, with prices starting from $732 and $797, respectively.

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

    The most popular flight routes from Sydney to Illinois are Sydney Kingsford Smith - Chicago O'Hare Intl, Sydney Kingsford Smith - Chicago Midway and Sydney Kingsford Smith - Lambert-St Louis.

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

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

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

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

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

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

    Currently, December is the cheapest month in which you can book a flight from Sydney to Illinois (average of $468). Flying from Sydney to Illinois in July is currently the most expensive (average of $920). 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

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

Top 2 airlines flying from Sydney to Illinois

Discover the top 2 airlines that operate flights from Sydney to Illinois. 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 June 24, 2026.
AirlineCheapestAverageFlexibilityOn-time
Qantas AirwaysCheapest$970Average$1,401FlexibilityNo cancel feeOn-time74%
United AirlinesCheapest$1,113Average$1,279FlexibilityNo cancel feeOn-time69%

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