$602 Find Cheap Flights from Sydney to Illinois

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from Sydney to Illinois departing on 15/10. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
1 adult
1 adult, Economy

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These are the airlines KAYAK users have selected most often from within our search results in flight searches from Sydney to Illinois.
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Sydney to Illinois.
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Cheap Flights from Sydney to Illinois

Cheapest return prices found by our users on KAYAK in the last 72 hours
Chicago
Chicago1 stop$1,220
Chicago
Chicago1 stop$1,220

Book Cheap Sydney to Illinois Plane Tickets

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for return flights from Sydney to Illinois that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.
Discover the best prices for you by selecting your travel dates on KAYAK.

Recent return flight deals from Sydney to Illinois

Wed, 15 Oct - Tue, 21 Oct
Air Canada Logo
10:20 - 20:46SYD-STL
26h 26m2 stops
Air Canada Logo
13:40 - 08:20STL-SYD
26h 40m2 stops
$1,207Air Canada
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Tue, 28 Oct - Thu, 30 Oct
Air Canada Logo
10:20 - 14:41SYD-ORD
20h 21m1 stop
Air Canada Logo
15:40 - 08:35ORD-SYD
24h 55m1 stop
$1,220Air Canada
Find Deal
Mon, 18 Aug - Sat, 8 Nov
American Airlines Logo
09:10 - 19:09SYD-STL
24h 59m2 stops
American Airlines Logo
15:59 - 09:00STL-SYD
24h 01m2 stops
$1,263American Airlines
Find Deal
Mon, 18 Aug - Sat, 8 Nov
American Airlines Logo
09:10 - 20:18SYD-STL
26h 08m2 stops
American Airlines Logo
11:39 - 09:00STL-SYD
28h 21m2 stops
$1,270American Airlines
Find Deal
Mon, 13 Oct - Mon, 20 Oct
United Airlines Logo
10:30 - 20:46SYD-STL
26h 16m2 stops
United Airlines Logo
17:35 - 07:55STL-SYD
22h 20m1 stop
$1,282United Airlines
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Sun, 14 Sep - Sun, 21 Sep
United Airlines Logo
09:30 - 18:58SYD-STL
24h 28m2 stops
United Airlines Logo
11:05 - 06:55STL-SYD
28h 50m2 stops
$1,288United Airlines
Find Deal
Sat, 13 Sep - Sat, 20 Sep
 Logo
13:45 - 23:13SYD-ORD
24h 28m2 stops
 Logo
07:00 - 11:45ORD-SYD
37h 45m2 stops
$1,405
Find Deal
Wed, 13 Aug - Wed, 3 Sep
 Logo
06:00 - 05:38SYD-ORD
38h 38m2 stops
 Logo
15:40 - 07:20ORD-SYD
24h 40m1 stop
$1,488
Find Deal
Wed, 15 Oct - Tue, 21 Oct
Qantas Airways Logo
13:10 - 20:53SYD-STL
23h 43m1 stop
Qantas Airways Logo
17:09 - 06:55STL-SYD
21h 46m1 stop
$1,595Qantas Airways
Find Deal
Mon, 13 Oct - Tue, 21 Oct
Qantas Airways Logo
10:10 - 23:05SYD-STL
28h 55m1 stop
Qantas Airways Logo
06:39 - 08:05STL-SYD
33h 26m1 stop
$1,653Qantas Airways
Find Deal
Booking Insights

KAYAK's insights & trends for Sydney to Illinois flights

Get data-powered insights and trends into flights from Sydney to Illinois to help you find the cheapest flights, the best time to fly, and much more.

How much is a round-trip flight from Sydney to Illinois?

What is the cheapest month to fly from Sydney to Illinois?

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from Sydney to Illinois, removes the top 0.1% to account for outliers, and then takes the median of all values for each month.

The cheapest month for flights from Sydney to Illinois is February, when tickets cost $1,159 (return) on average. On the other hand, the most expensive months are December and September, when the average cost of return tickets is $2,423 and $1,872 respectively.

What’s the cheapest day of the week to fly from Sydney to Illinois?

The average price of all round-trip flights from Sydney to Illinois clicked on KAYAK for each day over the last 12 months.

When flying from Sydney to Illinois, you should consider leaving on a Monday and avoid Sundays if you are looking for the best rates. For your return to Sydney, you’ll find the best rates on Fridays and the most expensive ones on Thursdays.

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

To calculate weekly average prices, KAYAK takes all prices for each week before departure over the last year for round-trip flights from Sydney to Illinois, removes the top 0.1% to account for outliers, and then takes the average of all the values for each week.

To get a below-average price on a flight from Sydney to Illinois, you should book around 4 weeks before departure, which saves you about 24% compared to booking last-minute. For the absolute cheapest price, our data suggests you should book 20 weeks before departure.


Good to know

Low seasonFebruary
Cheapest flight$602
Best time to beat the crowds (28% less expensive on average)
Most popular time to fly (1% more expensive on average)
Flight from Sydney to Chicago O'Hare Airport

FAQs - booking Illinois flights

  • How does KAYAK find such low prices on flights from Sydney to Illinois?

    KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Sydney to Illinois.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Sydney to Illinois?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight from Sydney to Illinois is likely to change within 7 days, so travellers know whether to wait or book now.

  • What is the Hacker Fare option on flights from Sydney to Illinois?

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional return ticket. You could then fly from Sydney to Illinois with an airline and back with another airline.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Sydney to Illinois?

    Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying from Sydney to Illinois up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

  • What is the cheapest time of day to fly to Illinois?

    The cheapest time of day to fly to Illinois is generally in the evening, when retur flights cost $1,121 on average. Morning departures are around 11% more expensive than evening flights, on average. The most expensive time of day to fly to Illinois is generally in the morning, which is peak travel time and where the average cost of a ticket is $1,240.

Reviews of the top 5 airlines flying from Sydney to Illinois

 
See real verified KAYAK customer reviews for airlines flying from Sydney to Illinois. Airline scores are aggregated from all reviews left by passengers on KAYAK after flying with an airline. KAYAK doesn’t show reviews that are older than 5 years. Learn how KAYAK collects reviews.
Need help choosing which airline to fly with from Sydney to Illinois? KAYAK airline reviews give an overall score for each airline based on loads of factors, including comfort, boarding, in-flight entertainment and more, to make your decision easier. See airline scores according to verified KAYAK customer reviews.
8.4
ANAOverall score based on 922 reviews
8.2Comfort
8.7Crew
8.5Boarding
7.7Food
7.9Entertainment
Airline reviews

Purchased WiFi was slow to non functional. Staff was not personable or friendly. Seats were cramped. Boarding took long but I expected that.

2.0 MediocreJeremy, July 2025CRW - ORD
Read more ANA reviews

Purchased WiFi was slow to non functional. Staff was not personable or friendly. Seats were cramped. Boarding took long but I expected that.

The crew was excellent. The flight was delayed for 20 to 25 minutes. We did arrive a bit later than expected. The AC could have been better.

Very disappointed with the seat selection. During the booking, I selected seats such that my wife and I would sit next to each other. However, during check-in, we found out that the airline changed our seats and we were seated apart; and I was stuck in the middle seat with two strangers. Very disappointing experience. We would not fly ANA next time.

Luckily I just tried to sleep. But the entertainment system was awkward to operate. I hate all this stuff with apps and adding it to your phone and all. It is a nuisance. I would prefer a good magazine or newspaper in the pocket in front of me or available.

Upgrade the comfort, food and attendants. Also we arrived in Houston in the morning. The meal they served two hours before our arrival was a dinner entree. It would have been a lot nicer and much more appropriate to have had breakfast.

Wonderful I would recommend it to fly & ride with ANA.

Poor. We weren’t able to check in online (for several hours until we gave up) for no apparent reasons although our passports were loaded successfully. When we were at the airport check-in, a rep helped us at the kiosk but she disregarded the KTN provided to her so we had to come back for it after being questioned by the TSA person…

Flight delayed by one day and everything was so disorganized by the airline.

Everything was good may improve some alcohol drinks and amenities during fly

All the food seemed to have onions. I don't eat onions. Anyway, everything else was great. The biggest downside was the underpricer company that purchased the tickets from ANA. Underpricer never provided the United Airlines booking number. ANA was a code share and all our flights were on United. I finally was able get booking numbers from Ujuted on X. They saved me from the upsales underwriter tried to saddle my wife and me with.

Poor! This flight was delayed 14 hours. There was no assistance in helping customers find other routes to their destination, nor any other kind of support. It was a chaotic experience. I'm not likely to fly with AA going forward.

Business class points redemption - good value for points paid, dubious value if out of your own pocket, domestic class business product okay for this length of flight. The flight left and arrived on time, crew were good, aircraft was a bit old and tired, but still miles ahead of their competitors in Virgin and Jetstar.

Airline running better than post Covid, proper boarding process now implemented, some aircraft feeling a bit old and tired, crew fine, online experience better.

We were upgraded and after just a short delay in attending to a safety check we were on our way. Would definately fly Qantas International on their Dreamliner again.

Five hour flight instead of four hours due to westerly headwinds which wasn’t the fault of Qantas !

I tried to check in online but was unable to do so. I stood in line for nearly two hours to check in. American Airlines was understaffed. When I finally got to the kiosk to check in, I was still unable to check in. No AA staff was available to help. Finally one of the airport security agents who was helping passengers became of lack of AA Staff told me: “I think the reason you can’t check in is that you are starting your name with an upper case letter when you write it. Just write it with all lower case letters.” That did allow me to check in. HOW COULD ANYONE POSSIBLY KNOW THAT IF THEY USE AN INITIAL UPPER CASE LETTER TO SPELL THEIR OWN NAME, AA WOULD NOT ALLOW THEM TO CHECK IN?????? Then I had to wait in line over half an hour again to drop off my baggage. Although I arrived at the airport 3 hours early, by the time I got to the gate, they had already started boarding.

One of the oldest most uncomfortable "lay down" seats I've ever experienced. Old plane and old seats that don't lay flat. The seat back does not even recline - at all. Instead the legrest awkwardly extends to fill the gap between a small cubby into which you must insert your feet/legs. I am 5' 11" and could not lay straight but had to tuck my knees. Ticket was also very expensive. Would not recommend flying business/first on Finair from Melbourne to Bangkok and will not do so again myself.

The wifi was out. Otherwise it was great flight. Richard, as CSM, was excellent.

Traditional economy class. Not a full flight so spare seats. Food and drinks were good

Was bumped to a later flight because of inefficiency on part of the airline.

I found the staff to not be very attentive at all. When paying for Business Class you expect a certain type of service and that was not found. They were almost rude even

Weather delay in Chicago?. No sense of urgency to make connection in Chicago for our connecting flight that wasn't delayed. Connection was missed.

Overall it was good. I missed my connection but I was put on another flight.

Overall a very poor experience - booked premium economy tickets but due to last minute flight delays , all my itinery went for a toss and had to fly economy class with no access to lounge or any compensation by united airlines to make up for the flight delays . i had expected better experience than that from united.

It was fine, definitely older planes with no charging or anything. There’s no entertainment set up on board, but it is nice that they allow you to access the in flight entertainment from your phone without having to pay for the Wi-Fi and they do offer free texting.

I liked that the flight was nonstop from ORD to CIU for $200 round trip.

The schedule to Moline changed 5 times. The gate changed 6 times. That is a pathetic way to run an airline. No wonder that no one in our company flies on United Express to or from Moline. Changes happen most of the time. I learned my lesson on this trip…never again!

All flight attendants could benefit by taking an international flight on Qantas Airline. Qantas attendants are much more hospitable in every way. Much superior than and attendants on any US airline.

While the staff was pleasant and helpful, the following observations are for your awareness. There was some delay on the tarmac on take off and landing. The paid lunch/food offerings were limited. Entertainment was only available on WiFi at a cost.

The first flight was better in terms of the aircraft.

Couldn’t get the door on the plane to close leading to a nearly 2 hour delay. But, hey at least they didn’t cancel the flight.

Very clean and comfortable cabin. Amazing Mediterranean salad for lunch before landing. Great range of films to watch. Really quiet and easy to sleep on the flight also. The initial food was a bit weird: odd fried chicken pieces in some weird white gloop, but that would be my lack of cultural knowledge on the grub. Salad more than made up for it at the other end. Staff were super attentive and helpful. Great and easy flight

The flight was fine and the crew awesome. The problem is ORD and AA. Computers went down, ORD fell apart and a 40 min flight turned into a 3 hour trip. Guess the answer is to not try and fly to ORD after noon. But, as I said, crew was awesome and did everything they could to lesson the flight time.

The flight was fine but the 8 hour delay in Chicago was awful - 5 gate changes and repeated delays without an explanation. No vouchers. Nothing.

Most miserable flight ever. We waited almost 2 hours on the runway because the flight was oversold. American offered $1200 credit. Then there was some nonsense about weight distribution. Ridiculous. No food for 8 plus hours on the flight. I will be writing a letter.

The flight was 2 hour delayed, otherwise everything was excellent. The delay was due to the hourly limit requirement so given that as a reason, I'm happy with the flight!

Not sure the logic of the boarding in Groups. I was loaded first on the aisle. Then the guy in the middle. Then the guy by the window. Constantly holding up the other people boarding behind them with us blocking the aisle and this happened in most of the other rows

To start, I’d like to say that every American Airline personnel I interacted with on the ground, especially flight crew, was very friendly and did their best to help me out. Despite this, however, my experience with the airline was an entire mess. The 7:19 PM flight was heavily delayed due to weather, and pushed to 10:30 AM the next morning. Because of this, I had to spend the night inside of the airport. At some point later in the night, I got an email saying that the flight had been canceled. I called the support number, and the representative on the other line told me that the flight was still on and that I didn’t need to rebook. The next morning, no one came to the gate to open the door for the crew until almost 11 AM. By this time the flight crew had been waiting for over an hour, and they had called management to get someone to open the door for them multiple times. Around 11:30, the gate screen had changed to a different flight. I ended up buying a last minute ticket with Southwest airline just to get to Chicago, because the next flight with American wasn’t until 7:19 pm that day. Now, earlier that morning my suitcase had been sent ahead of me to ORD. I went to baggage claim to ask them if I could have my suitcase forwarded to where I was staying. The representative at SDF baggage claim said they could and put the claim in for me. As I was going back through TSA, I got an email that the airline had found my suitcase, but the next step was to send it BACK to SDF. I called the airline support number again, and I made it clear that my suitcase needed to stay in Chicago and to not come back to SDF. The representative told me that they would hold my suitcase at ORD and that it wasn’t going to be forwarded anywhere. Once I got there, I found that they had loaded my suitcase onto a plane to send it back to SDF. Thankfully, I had gotten to the baggage claim counter in time for them to put in a request to bring my suitcase back up. My refund with the airline is processing already, but because of this entire experience and miscommunication at every turn of the way, I will not book with American Airlines in the future.

The plane was late and then sat on the runway for almost 45 minutes before taking off.

Crew professional. Easy bag drop off. On time. Good entertainment.

I did not noticed baggage was separate - I had assumed international flights included luggage, so it surprised me I had to pay to check a bag.

Flight got delayed for no reason. And Air Canada was doing 3 boardings via the same gate. It was chaotic!

My return flight experience was one of the worst times I have had traveling anywhere this year. Not because of the flight. It was because there was not enough time allocated to deplane, go through U.S. Customs and U.S. Security to get to the gate for the connecting flight to Boston which I missed, There was well less than an hour between my landing in Montreal from Prince Edward Island to my connecting gate. I even called Air Canada on the morning of my return and noted my concern over the short layover time, not more that 45 minutes. The initial flight was four minutes late. I was seated in the rear of the first aircraft, and it took at least 20 minutes to deplane. The U.S. Customs was a considerable distance from the gate at which we landed. The need for double security seemed unnecessary and redundant. The distance from the security to my gate was again fairly great, and the wrong gate number was listed on my boarding pass. The agent I approached at the flight that was going to Newark, New Jersey was too busy to answer my question as to what gate was for Boston. When I got to the right gate, they had just closed the door to the aircraft even though I arrived a minute late. If I knew the distance to Customs and from Security to the gate, I would have asked for a seat on the next available flight which was 4:30 pm. When I made my call at 6:00AM that morning. When I asked the agent at the Boston gate, he said that the 4:30 flight was already “OVERBOOKED!” I was put on an 8:30 PM flight and didn’t get home until MIDNIGHT. I then had to care for a barnful of hungry animals and didn’t get to bed until 2:00 AM.

From Montreal to Cincinnati the flight was perfect! Flight free and everyone was perfect and a pleasure to travel with. But from Casablanca to Montreal the flight crew were quite cold, unhelpful, also seemed to scold many passengers instead of simply educating or instructing them. There were a couple for sure I could describe but not name… i was really shocked bc my experience w air Canada is typically a good one at the very least. It seemed something was very much so I’m the air w the crew. The two older lady crew members and the male were amazing but the younger lady crew members w the exception of one were very clique-y and snarky, sassy

Seating wasn’t too cramped; I don’t understand how luggage bins get full if there are enough for each person. Shouldn’t there be room for the designated carry-on and personal item for each passenger at their seat? THEN, IF for some reason extra room is available for someone who prefers it, then shifts can occur. I’m simply saying it seems that I should have primary access to the storage bin at my seat and underneath in front of me. It was suggested that I go to the back of the plane to store my carry-on when I paid to have access to the first seat after 1st class. The additional stress and inconvenience could be avoided and I think all passengers and flight crew are interested in guidelines that are fair, clear, and reduce tension.

Wonderful airline. All staff were pleasant and helpful. What is sad is that it wasn’t grand gestures just everyday pleasantness and friendliness that are missing from the other airlines I have flown recently.

Friendly efficient crew, but plane had no way to charge phone. That is a near necessity with today’s travel where we carry out travel documents on our phones.

The flight was delayed for 2 hrs. We were changed to a smaller plane, which was shaking a lot.

Bad service as well. Another 3hr delayed flight from chicago to Charlotte.

Very bad service the way back we was on the way for r two days very bad condition and waiting for luggage till now

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