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Illinois

$425+ 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 10/15. Fares are subject to change and may not be available on all flights or dates of travel.
SYD — ORD
Oct 15 — Oct 221
Wed 10/15
Wed 10/22
1 adult, Economy
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Cheap flight deals from Sydney to Illinois

Keep the following information in mind while searching for Sydney to Illinois flight deals. Data was last updated September 15, 2025.

Round-trip from

$809
(Air Canada)

One-way from

$425
(Trip.com)

Popular in

December

Cheapest in

March

Average price

$1,148
From Sydney Kingsford Smith to Illinois
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One-way flight from Sydney Kingsford Smith to Illinois
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Highest demand for flights based on searches. 22% potential increase in price ($296 potential increase over avg. RT price).
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Cheapest flight prices on average. 4% potential price decrease ($46 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 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 September 15, 2025.

This Air Canada deal was found by Cheapflights users on 9/15. 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 Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/44:00 pmSYD - STL
2 stops64h 29mAir Canada
Thu 12/111:35 pmSTL - SYD
2 stops24h 20mAir Canada
Deal found 9/15$830
This Air Canada deal was found by Cheapflights users on 9/13. 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 Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/44:00 pmSYD - STL
2 stops64h 29mAir Canada
Wed 12/101:35 pmSTL - SYD
2 stops48h 20mAir Canada
Deal found 9/13$831
This American Airlines deal was found by Cheapflights users on 9/13. 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.
Fri 12/511:15 amSYD - STL
2 stops22h 04mAmerican Airlines
Sat 12/136:55 amSTL - SYD
1 stop33h 05mAmerican Airlines
Deal found 9/13$833
This Air Canada deal was found by Cheapflights users on 9/13. 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 Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/44:00 pmSYD - STL
2 stops61h 39mAir Canada
Mon 12/84:05 pmSTL - SYD
2 stops48h 30mAir Canada
Deal found 9/13$836
This United Airlines deal was found by Cheapflights users on 9/15. 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 12/111:50 amSYD - STL
1 stop39h 14mUnited Airlines
Tue 12/94:45 pmSTL - SYD
2 stops23h 20mUnited Airlines
Deal found 9/15$850
This United Airlines deal was found by Cheapflights users on 9/15. 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 12/112:10 pmSYD - STL
2 stops43h 15mUnited Airlines
Mon 12/81:35 pmSTL - SYD
2 stops26h 30mUnited Airlines
Deal found 9/15$851
This Gotogate deal was found by Cheapflights users on 9/15. 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 Gotogate is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/811:20 amSYD - ORD
2 stops44h 50mAir Canada
Sat 11/223:40 pmORD - SYD
1 stop24h 55mAir Canada
Deal found 9/15$868
This BestPriceTravel deal was found by Cheapflights users on 9/13. 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 BestPriceTravel is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/309:20 amSYD - ORD
1 stop22h 22mAir Canada
Wed 11/123:40 pmORD - SYD
1 stop24h 55mAir Canada
Deal found 9/13$874
This Air Canada deal was found by Cheapflights users on 9/14. 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 Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/2910:20 amSYD - ORD
2 stops37h 40mAir Canada
Wed 11/53:40 pmORD - SYD
1 stop24h 55mAir Canada
Deal found 9/14$881
This Priceline deal was found by Cheapflights users on 9/15. 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 Priceline is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/3010:20 amSYD - ORD
1 stop20h 21mAir Canada
Thu 11/63:40 pmORD - SYD
1 stop24h 55mAir Canada
Deal found 9/15$883
This Air Canada deal was found by Cheapflights users on 9/15. 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 Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/44:00 pmSYD - STL
2 stops64h 29mAir Canada
Fri 12/129:00 amSTL - SYD
2 stops52h 55mAir Canada
Deal found 9/15$897
This American Airlines deal was found by Cheapflights users on 9/13. 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.
Sun 11/3011:20 amSYD - STL
2 stops29h 36mAmerican Airlines
Tue 12/91:43 pmSTL - SYD
2 stops26h 17mAmerican Airlines
Deal found 9/13$899

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 September 15, 2025.
Use the filters below to find and compare flights from Sydney to Illinois that are best for you.

Fly from

Sydney

Fly to

Illinois

Route

Depart

Return

Price

SydneySt. Louis

SYD - STL

SYDSTL

Sydney Kingsford Smith

Thu 3/12

10:20 am-3:29 pm

2 stops45h 09m

Lambert-St Louis

Mon 3/16

4:05 pm-8:35 am

2 stops48h 30m

$809

SydneySt. Louis

SYD - STL

SYDSTL

Sydney Kingsford Smith

Tue 12/2

11:20 am-11:07 pm

2 stops28h 47m

Lambert-St Louis

Sat 12/13

1:55 pm-9:00 am

2 stops26h 05m

$833

SydneySt. Louis

SYD - STL

SYDSTL

Sydney Kingsford Smith

Tue 12/2

11:20 am-11:07 pm

2 stops28h 47m

Lambert-St Louis

Tue 12/9

1:55 pm-9:00 am

2 stops26h 05m

$833

SydneySt. Louis

SYD - STL

SYDSTL

Sydney Kingsford Smith

Thu 12/4

11:20 am-8:57 pm

2 stops26h 37m

Lambert-St Louis

Mon 12/8

4:05 pm-6:55 am

2 stops45h 50m

$836

SydneySt. Louis

SYD - STL

SYDSTL

Sydney Kingsford Smith

Mon 12/1

11:50 am-10:22 pm

1 stop27h 32m

Lambert-St Louis

Mon 12/8

3:19 pm-9:05 am

2 stops24h 46m

$850

SydneySt. Louis

SYD - STL

SYDSTL

Sydney Kingsford Smith

Mon 12/1

11:50 am-10:04 am

1 stop39h 14m

Lambert-St Louis

Tue 12/9

4:45 pm-9:05 am

2 stops23h 20m

$850

SydneySt. Louis

SYD - STL

SYDSTL

Sydney Kingsford Smith

Tue 12/2

12:10 pm-4:27 pm

1 stop21h 17m

Lambert-St Louis

Tue 12/9

5:30 pm-9:15 am

1 stop22h 45m

$850

SydneySt. Louis

SYD - STL

SYDSTL

Sydney Kingsford Smith

Wed 12/3

11:50 am-10:45 pm

2 stops27h 55m

Lambert-St Louis

Wed 12/10

9:00 am-9:15 am

2 stops31h 15m

$851

SydneySt. Louis

SYD - STL

SYDSTL

Sydney Kingsford Smith

Tue 12/2

12:10 pm-10:45 pm

2 stops27h 35m

Lambert-St Louis

Mon 12/8

3:19 pm-9:05 am

3 stops48h 46m

$851

SydneyChicago

SYD - ORD

SYDORD

Sydney Kingsford Smith

Sat 11/8

11:20 am-3:10 pm

2 stops44h 50m

Chicago O'Hare Intl

Sat 11/22

3:40 pm-9:35 am

1 stop24h 55m

$868

Flights are sorted by cheapest round-trip flights first.

Deals found on 9/15

Showing 1-10 of 45 results
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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, August is the cheapest month in which you can book a flight from Sydney to Illinois (average of $245). Flying from Sydney to Illinois in March is currently the most expensive (average of $321). 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 SYD to IL?

Find hourly flight availability from Sydney to Illinois. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated September 15, 2025.

When flying from Sydney to Illinois, the time of day you decide to fly out makes little to no difference towards the overall price you’ll pay on tickets.

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 September 15, 2025.
Get a feel of what it's like to fly with Qantas Airways, United Airlines, and American 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
905 reviews

Food

6.9

Boarding

7.7

Comfort

7.5

Crew

8.2

Overall

7.5

Entertainment

7.2

Reviews

1 / 20
10.0
Excellent

Anonymous,Sep 2025

SYD - BNE

Great. Except I haven’t claimed my free lounge passes since 2022 on my Qantas credit card. That’s lots of flights I would have booked if you’d reminded me
Qantas Airways
7.5
Good
905 reviews
Qantas Airways
7.5
Good
905 reviews

Food

6.9

Boarding

7.7

Comfort

7.5

Crew

8.2

Overall

7.5

Entertainment

7.2

Reviews

1 / 20
10.0
Excellent

Anonymous,Sep 2025

SYD - BNE

Great. Except I haven’t claimed my free lounge passes since 2022 on my Qantas credit card. That’s lots of flights I would have booked if you’d reminded me
United Airlines
7.4
Good
8,929 reviews
Qantas Airways
7.5
Good
905 reviews

Food

6.9

Boarding

7.7

Comfort

7.5

Crew

8.2

Overall

7.5

Entertainment

7.2

Reviews

1 / 20
10.0
Excellent

Anonymous,Sep 2025

SYD - BNE

Great. Except I haven’t claimed my free lounge passes since 2022 on my Qantas credit card. That’s lots of flights I would have booked if you’d reminded me
American Airlines
7.2
Good
10,000 reviews
Qantas Airways
7.5
Good
905 reviews

Food

6.9

Boarding

7.7

Comfort

7.5

Crew

8.2

Overall

7.5

Entertainment

7.2

Reviews

1 / 20
10.0
Excellent

Anonymous,Sep 2025

SYD - BNE

Great. Except I haven’t claimed my free lounge passes since 2022 on my Qantas credit card. That’s lots of flights I would have booked if you’d reminded me

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 Air Canada, American Airlines, and United Airlines fly from Sydney to Illinois in about 27h 32m. The time it takes to get you to your destination can typically vary by up to 17h 37m. 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?

    $509 is the cheapest one-way deal found within the past few days, from Delta. You may also be able to find cheap deals on United Airlines and Air Canada, with prices starting from $509 and $581, 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, August is the cheapest month in which you can book a flight from Sydney to Illinois (average of $245). Flying from Sydney to Illinois in March is currently the most expensive (average of $321). 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 Sydney to Illinois

See prices for flight routes from nearby airports that may be better suited for you.
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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 September 15, 2025.
AirlineCheapestAverageFlexibilityOn-time
Qantas AirwaysCheapest$631Average$762FlexibilityNo cancel feeOn-time74%
American AirlinesCheapest$884Average$1,129FlexibilityNo cancel feeOn-time71%

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