$637 Find Cheap Flights 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 Australia 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

KAYAK searches hundreds of travel sites at once for deals on flights to Illinois

 
These are the airlines KAYAK users have selected most often from within our search results for flights to Illinois
These are the airlines KAYAK users have selected most often from within our search results for flights to Illinois
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Cheap Flights to Illinois

Cheapest return prices found by our users on KAYAK in the last 72 hours
Chicago
Chicago2 stops$1,212
Moline
Moline2 stops$1,356
Chicago
Chicago2 stops$1,212
Moline
Moline2 stops$1,356

Book Cheap Illinois Plane Tickets

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for return flights 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 to Illinois

Thu, 12 Mar - Mon, 16 Mar
Air Canada Logo
10:20 - 15:29SYD-STL
45h 09m2 stops
Air Canada Logo
16:05 - 08:35STL-SYD
48h 30m2 stops
$1,212Air Canada
Find Deal
Tue, 17 Feb - Thu, 26 Feb
Air Canada Logo
10:45 - 19:30BNE-ORD
24h 45m2 stops
Air Canada Logo
08:00 - 08:45ORD-BNE
32h 45m2 stops
$1,212Air Canada
Find Deal
Wed, 3 Dec - Fri, 12 Dec
American Airlines Logo
11:20 - 22:22SYD-STL
28h 02m2 stops
American Airlines Logo
06:55 - 09:00STL-SYD
33h 05m1 stop
$1,248American Airlines
Find Deal
Mon, 13 Oct - Mon, 20 Oct
United Airlines Logo
11:55 - 09:52MEL-STL
37h 57m2 stops
United Airlines Logo
17:28 - 09:15STL-MEL
23h 47m2 stops
$1,265United Airlines
Find Deal
Thu, 30 Oct - Thu, 6 Nov
American Airlines Logo
11:20 - 17:38SYD-STL
22h 18m2 stops
American Airlines Logo
14:29 - 09:00STL-SYD
25h 31m2 stops
$1,266American Airlines
Find Deal
Mon, 1 Dec - Tue, 9 Dec
United Airlines Logo
11:50 - 10:04SYD-STL
39h 14m1 stop
United Airlines Logo
16:45 - 09:05STL-SYD
23h 20m2 stops
$1,274United Airlines
Find Deal
Tue, 30 Sep - Wed, 12 Nov
Qantas Airways Logo
09:10 - 15:51SYD-ORD
21h 41m1 stop
Qantas Airways Logo
18:03 - 09:00ORD-SYD
21h 57m1 stop
$1,419Qantas Airways
Find Deal
Wed, 8 Oct - Wed, 29 Oct
Air New Zealand Logo
09:55 - 23:12SYD-ORD
29h 17m2 stops
Air New Zealand Logo
15:40 - 10:30ORD-SYD
26h 50m2 stops
$1,495Air New Zealand
Find Deal
Thu, 13 Nov - Tue, 18 Nov
Air New Zealand Logo
12:10 - 22:59MEL-ORD
27h 49m2 stops
Air New Zealand Logo
13:00 - 17:40ORD-MEL
35h 40m2 stops
$1,518Air New Zealand
Find Deal
Wed, 26 Nov - Tue, 27 Jan
Qantas Airways Logo
17:45 - 23:59SYD-ORD
23h 14m1 stop
Qantas Airways Logo
12:25 - 06:10ORD-SYD
24h 45m1 stop
$1,584Qantas Airways
Find Deal
Booking Insights

KAYAK's insights & trends for flights to Illinois

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

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

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for flights from Australia 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 Australia to Illinois is February, when tickets cost $1,467 (return) on average. On the other hand, the most expensive months are December and September, when the average cost of round-trip tickets is $2,678 and $1,987 respectively.

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

To calculate weekly average prices, KAYAK takes all prices for each week before departure over the last year for round-trip flights 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 Australia to Illinois, you should book around 2 weeks before departure, which saves you about 21% compared to booking last-minute. For the absolute cheapest price, our data suggests you should book 21 weeks before departure.

Good to know

Low seasonJanuary
Cheapest flight$637
Best time to beat the crowds (2% less expensive on average)
Most popular time to fly and prices are also 4% lower on average.
Flight from Sydney to Chicago O'Hare Airport

FAQs - booking Illinois flights

  • How does KAYAK find such low prices on flights from Australia 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 Australia to Illinois.

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

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight from Australia 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 Australia 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 Australia 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 Australia 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 Australia 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 day to fly to Illinois?

    Based on KAYAK data, the cheapest day to fly to Illinois is Tuesday when return tickets can be as cheap as $1,893. On the other hand, the most expensive day to fly is Sunday, when return prices are $2,141 on average.

  • 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.

Top tips for finding cheap flights to Illinois

  • Enter your preferred departure airport and travel dates into the search form above to unlock the latest Illinois flight deals.

Reviews of the top 5 airlines flying to Illinois

 
See real verified KAYAK customer reviews for airlines flying to Illinois. Airline scores are aggregated from all reviews left by passengers on KAYAK after flying with an airline from Australia to Illinois. 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 Australia 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.
8.0
Air New ZealandOverall score based on 505 reviews
7.4Entertainment
8.5Crew
8.2Boarding
7.3Food
8.0Comfort
Airline reviews

Not a comfortable trip, the seats are not good, and they look old.

4.0 OkayAnonymous, July 2025AKL - SFO
Read more Air New Zealand reviews

Not a comfortable trip, the seats are not good, and they look old.

Lost my luggage and brought someone else luggage to my airport.

Not entirely positive. It’s frustrating that everything is done through the united app. One of our flight attendants on our trip from San Francisco to MSP continually had trouble hearing people so she flipped her hair into people’s faces

I flew United from San Francisco to Auckland. My connecting flight from Auckland to Christchurch was canceled with no explanation. I was finally told the cancellation was due to fog. Even though it was clear when we landed. I am from San Francisco, I know what fog is! And I didn't see any fog. I was told the next available flight was 7 hours later. Unacceptable, they should have had a flight ready to go as soon as it was deemed safe to take off.

Our original flight was cancelled from SFO to AKL on 6/16/25. So we had to stay overnight at a hotel after a 12-hour layover plus 3-hour delay before the cancellation. Then had to fly to LA and then to AKL the following day losing an entire day of our vacation in NZ, that we can never get back.

Two hours was not enough time to transition from the international to domestic terminal. You have to go through customs, a biological hazard check, gather your luggage, take a bus to the domestic terminal and recheck your luggage. The bus was slow and crowded and the lines to recheck your bags were very long. We missed our connecting flight. Initially, the Air New Zealand officials were not helpful at all in helping to get us on another flight. Told us we would have to buy another ticket for a flight 11 hours later. Found another agent that was more helpful. He helped arrange to get us on standby for another flight three hours later. Had to ride in jump seats next to the flight attendants, but at least we eventually got to out destination.

Full flight. Flight attendants were harried. Otherwise, fine for the typical cramped seating conditions in coach.

Great! Flight was delayed by 30 mins but all was great. Thanks.

The 10hr flight was a comfortable as it could be in row 57. The food was just very bad….bland and soggy!

The business class upgrade meant a good sleep on the way home after a long week away. Excellent service, great food, and comfortable seat/bed for the journey.

My flight from Dallas to Sydney was cancelled. My entire trip was rerouted to include the following: Hartford to Washington DC Washington DC to JFK JFK to Auckland Auckland to Christchurch I paid for an aisle seat on the flight to Auckland and was asked if I would take a window seat to accommodate a family. The agent at the podium failed to mention that the family had a 3 month old baby and that a bassinet would be used during the 16 hour flight. The only way I could get out of my seat was to crawl under the bassinet of the sleeping baby. I think it is wrong that I was no given the choice to sit in another seat, that the agent knew what she was doing and chose to not properly disclose my seating arrangement. Terrible treatment.

they ran out of fruit for breakfast and so I just had a yogurt instead. other than that the flight was good

by the time they got to our row, they were out of some of the food options. games and movies were great but maybe more game options like tetris or pac man would be great

A few more inches of legroom is all i ask

Great as usual, some delays but well communicated and made up for in the air

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 !

My flight was delayed about 1 1/2 hours in Chicago, but other then that it was a good flight.

Flight attendant in first class gave poor service (like he didn't want to be there) and food was awful. We sat waiting for gate upon arrival over 45 mins.

Inoperable monitor left no entert for 9 hours. Crew was not helpful Food was awful.

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.

The flight was on time and crew were nice, seats were tight and there was entertainment available

Any flight to ORD after about 2pm this summer has been challenging. Flight was delayed getting in (coming from ORD) and that led to it not leaving before a ground stop due to lightening before they could fuel the plane, and so forth. They made up some time but we were still late in arriving at ORD, and that led to missed connections.

Food was ok, but not as good as I have had before on AA.

Pretty good. The food was just mediocre, the boarding and crew were good.

Worst flight ever. I was suppose to have a 3 1/2 hour layover in Chicago but got to the gate 4 minutes before boarding.

My flight got switched and my prepaid bag didnt transfer over properly so I paid to check ANOTHER BAG. I was placed in a middle seat and it was just miserable. At least it was a bulkhead row so I had legroom. The flight just never seem3d to end

They should have MSNBC available on board. A 4- hour flight should provide more than a cookie.

Was not able to watch most shows on the entertainment site. They would not load

On Wednesday, July 30 we were in mid flight from Manchester to Charlotte and we turned around because the right engine was malfunctioning. That was the last flight out of Manchester that night. I was rebooked for Thursday, which became a weather event Friday. There were no seats left on the flight from Manchester to Charlotte. Consequently I didn’t leave Manchester until Saturday morning and we flew to Chicago so to say the least my scheduled flight and return to Iowa was three days off and it messed with my business schedule. Consequently cash flow. I would like some sort of acknowledgment of this event.

Dreadful experience. Our flight was delayed more than 8 hours due to a maintenance issue and the assistance from rebooking was poor. I was travelling with a bad knee and needed assistance waited in one place more than 3 hours before someone came with a wheelchair. The woman next to me was a 91 year old great grandmother who had waited more than 4 hours. There were moments of support from the staff but it appeared as they were going against the direction of management. It was apathy, lack of ownership and dismissive responses with small moments of kindness and understanding typically from grey haired, female, veteran staff..

I liked the behaviour of the crew members.The flight was good.

1 hour late No hot drinks No restroom in the back of the plane

I swear airplane seats keep getting smaller and smaller but everything else was great. Smooth sailing and we got in early.

No food to provide, they forgot that, in some cases, people stay at the airport for hours without food. Now, to provide them with food, they have to ask them to pay, because some don't have money. That way, they can't eat.

After a long flight from Tokyo, our connecting flight home was canceled due to “maintenance” while we were on our layover in Toronto. Very frustrating to close out our honeymoon, although I’m sure others had it even worse during last week’s strike. Air Canada staff at Pearson Airport are the one thing that kept me remotely at peace during this — they were very helpful and deserve a lot of props. But I would not fly Air Canada again.

I had wonderful wheelchair assistance through the Montreal airport onto the flight. Air Canada was excellent in this both at the Fredericton airport and the Montreal one where an attendant helped us through customs as well as transport and baggage security.

Horrible flight cancelled had to buy another very expensive ticket

Flight was cancelled last minute due to Air Canada strike leaving us stranded and having to stressfully find a way home that cost hundreds of dollars in excess cost added to the trip. Having just experienced our mother's funeral service, this was not a good way to end our trip.

Air Canada marooned me in Canada with no way back home during my summer vacation. I had to buy a last minute flight ticket for over $500 to make it back home. I have their credit card and have flown them for years. Never again.

Flight was cancelled last minute. Had to scramble and purchase a $2000 flight through a separate airlines. Stuck in Toronto two extra days. Missed my first two days on a new job. Had to rent a car for an additional two days. Scrambled to fins a place to live those extra two days. Spent a ton of extra money and lost a lot of money, as well as made a poor impression at work. Difficult difficult difficult

Everything you need to know for your flight to Illinois

Cabin class types available on flights to Illinois

Cabin classes available on flights to Illinois. Prices are the lowest found on KAYAK over the last 7 days. Price and availability is not guaranteed.

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