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Find cheap flights from Ontario to Illinois from $59

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from Ontario to Illinois departing on 5/22. 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
0 bags
Fri 6/7
Fri 6/14

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Best Illinois Flight Deals

Cheapest round-trip prices found by our users on KAYAK in the last 72 hours

Chicago
Chicago1 stop$133
Moline
Moline1 stop$286
Peoria
Peoria1 stop$427
Bloomington
Bloomington1 stop$261
St. Louis
St. Louis1 stop$118

Good to know

Low season

February

High season

May

Cheapest flight

$59
Best time to beat the crowds with an average 32% drop in price.
Most popular time to fly and prices are also 4% lower on average.
Flight from Ontario to Chicago O'Hare Airport

FAQs - booking Illinois flights

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

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

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

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

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

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Ontario 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 to Illinois from Ontario up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

See more FAQs

Top tips for finding cheap flights to Illinois

  • Morning departure is around 14% more expensive than an evening flight, on average*.
*Average of the lowest prices shown in KAYAK’s search results for departures within the next 30 days

Top 5 airlines serving from Ontario to Illinois

 
Need help choosing which airline to fly with from Ontario 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.
8.2
China AirlinesOverall score based on 920 reviews
7.8Food
8.6Crew
8.3Boarding
8.1Entertainment
8.0Comfort
Airline reviews

Comfort was left wanting due to such a long flight, made the wife and I wish we could upgrade the seats to Business class or First Class, but did not have that option. Food was good but had very limited options and I have a dietary restriction which was difficult for the staff to accommodate since everything provided came with cheese on it. (Cheese could potentially kill me) Did not have an option to inform the staff until we were already in the air about the restriction and was not provided another option before flight departed.

8.0 ExcellentMichell, Feb 2024TPE - LAX
Read more about China Airlines reviews

Comfort was left wanting due to such a long flight, made the wife and I wish we could upgrade the seats to Business class or First Class, but did not have that option. Food was good but had very limited options and I have a dietary restriction which was difficult for the staff to accommodate since everything provided came with cheese on it. (Cheese could potentially kill me) Did not have an option to inform the staff until we were already in the air about the restriction and was not provided another option before flight departed.

The plane was uncomfortable. I paid extra for more legroom but the seat was still uncomfortable. Other seats on the same exact row didn’t have to pay extra but still have extra legroom. I didn’t understand why I needed to pay $170 for. It was Iike China airline just wants to make money off their passengers. It was unfair.

Better training to have qualified crews and services. My flight was from around 12 midnight Friday Taipei to Vancouver. After two hours first meal (2:00 Am -8:00 ) no crew available for even asking for some water. I was even willing to pay for water. For breakfast after 8 hours the only drink was tea and coffee no water or juice.

Free Wi-Fi could have been better in the Airport.

3 of the 4 flights had delays despite the weather being fine, but still managed to make all connections

Ask flight attendant for water during flight and she was a little rude get the water.

Baggage made it successfully to destination despite short layover. Appreciate that.

Staff were good and nice. There should me 3 meals instead of only 2 and snacks.

Excellent staff made the boarding process fast and easy. Friendly crews on both flights from Saigon to Taipei and Taipei to Los Angeles. Will fly China Airlines again.

For a long-haul flight, the crew did a very good job of keeping the lavatories clean and the aisles clear.

There was a loud squeaky sound the whole time we were flying.

I usually have a positive experience with Delta. Complimentary upgrades are always nice!

I didn’t not like that I could not select my seat and ended up with the worse seat.

The landing was bad and the hostess came two times and i was sleeping but when she served the person that nexts to me I woke up and she didn’t even asked me if I need any drink or snacks two times!!!!

Plane was late because of a mechanical malfunction and the food listed as available was not. Flight attendants seem over worked and under paid. They just done seem happy. And that can be seen in their faces.

Waited 3 hours on a plane to de-ice due to manpower issues. Waited another hour and a half once we landed because of a gate issue. Missed my connections. Created. A total of 13 hours of delay.

Great, on time departure, friendly and accommodating crew, great leg room, Smith flight

Plane was turned around due to fog half way into the flight, Delta did not properly direct passengers to stay on same flight and instead failed to properly rebook on Alaska

Like most domestic flights in the US, you are basically on your own with this airline when it comes to food, so be sure to purchase meals and drinks ahead of time or expect to arrive starving and dehydrated (like I was).

You need to be a hacker to get the (Free) WiFi

I was told we'd have a hot breakfast option in first class, so I chose not get a hot breakfast. It was a very strange meal, but the fresh fruit was very good quality. Service was excellent from ORD to ELP. No service from MBS to ORD, not even water. However, when flying American from FNT to ORD, which is a shorter flight, they at least pass out snacks and offer water.

The delays (5 hrs) were a comedy of errors, and the multiple safety issues encountered were very concerning.

The flight was delayed instead of leaving at 11 it left at 12.20

United WiFi is consistently unusable (it can take 10 mins to load a single web page). If you need Wifi to do work, be prepared to lose half a day of productivity.

Good movies, iffy pay WiFi, food ok- on time though and that was great!

Awful…flight was delayed more than 12hrs, missed all connections to Fort Wayne, IN, had to get flight to another city 2 hours from my destination, flight was again delayed by 40 mins because they did not have enough fuel, again missed a connection, finally arrived in Indiana at 11pm…but before my 2 hour drive home, ay, no Five That Our Luggage Never Made On The plane and Still In Chicago

Boarding was friendly and quick. While the plane model was older with no live tv, the entertainment was full of movies and tv shows. All food was available. Pilots were very communicative with status of the flight. Flight landed on time.

Flight was delayed by over an hour and gate checked bags took 15 minutes to be delivered to the jet bridge.

The Palm Springs to Chicago O’Hare was on Time and Palm Springs airport is easier navigate. As our connection was only an approximately 50 minutes, we asked staff for insights for the Chicago airport in terms of transferring into the other terminal from which our flight left, and they were unhelpful. However, the United App was very helpful in terms of notifications and even providing directions. The Chicago to Detroit flight was significantly delayed which we all know does happen. However, there were very few updates or notifications as to why this was happening when we would actually arrive. It took nearly 30 minutes for bags to make it to baggage claim. We arrived nearly 1 hour late on a 40 minute flight.

Flight cancelled due to fog. No other flights available for 36 hours. Directed by United to book passage on another carrier, and submit receipts for reimbursement. Did that. United now states they will not reimburse. Currently out 2 grand.

The CX617 from HK to BKK was delayed more than 1.5 hours.

This flight is frequently delayed. The connections seemingly are more frequently delayed. I’ve missed connections as a result twice on the same route to charlotte then Charleston. Final destination arrival has been the next day, twice in a row. No pilots, no crew. Too many excuses. Unfortunately, my days with American are over.

Entertainment was okay not because anything was wrong but it is a short flight so having no wifi is annoying but understandable. Crew was outstanding as usual

Those seats were way too narrow. I had the middle seat, one person was a very skinny person and we still couldn’t avoid touching each other anytime one of us moved. The other person was larger and we were basically sitting in each others lap the entire flight. There was zero entertainment. The flight was long enough to justify tvs, but no. Gotta sit there in your infant seat and twiddle your thumbs.

Flight was fine. It took an unusually long time to have baggage delivered to the carousel in ORD.

Average - flew with Jet Blue internal and it was far more comfortable and better food and entertainment. Notable difference

The flight got canceled due to mechanical issues, and he to be rebooked and missed my appointments for that day

The flight was scheduled to depart DCA at 12:30 pm but was delayed twice on the ground so that we were finally scheduled to depart at around 4:00 pm. Once we boarded, it was announced that takeoff would be delayed again to fix a hydraulic problem which delayed our eventual takeoff until around 5:00 pm. Once we departed, it was a smooth flight back to ORD. We did not get any explanation about what caused the original significant delay. In my experience, this happens frequently with AA.

The only problem experienced was a ground stop in Chicago due to weather. But the crew handled everything professionally. They prioritized rebooking those passengers who had connecting flights and then deplaning the other passengers. When the hold was lifted, they efficiently re-boarded all the passengers so that we could depart before our departure limit expired.

Our second leg to Jackson WY was unable to land due to weather. We were flown back to Dallas after stopping in SLC. We were given hotel rooms and vouchers. We were told that we would be back on the same plane in the morning. Instead we were given a different flight with different seats. Not a good experience. No one knew what was going on.

Our flight was delayed an hour, then when we got to board our flight finally, we were waiting in our seats for take off for 45 minutes before it was communicated that there was a maintenance issue therefore we waited on the plane for over an hour while that was resolved. We did not get to Phoenix until almost 3 hours after we were originally supposed to. This was the first and last time I will be flying Frontier.

There were 3 leg for the trip and each leg was delayed by 90 minutes or more. The boarding process takes forever with people waiting on the jetway even though most folks do not have carry-on. The whole process is poorly managed.

They cancelled the flight then did nothing to help us rebook. It was awful - I won’t fly with them again

The process of buying the ticket and navigating all the hidden charges that Frontier throws at you was a terrible experience. The actual airport experience and flying was fine.

The truck that was refueling the plane drove away with the hose still connected to the plane and ripped part of the plane off with it

Terrible. Seats are bad and the baggage policy is inconsistent

Better than I expected but I did pay for a seat and carry on bags ahead of time.

I hope to avoid flying with them in the future. First flight got cancelled then got stuck with a 13 hour layover in Denver. The process was long and frustrating to many people.

Flight was delayed on the runway for 40 minutes the crew did not even offer even water to passengers to compensate for the flight delayed. The flight was delayed due to aircraft mechanical issues. Worst customer service ever

The flight was delayed and I had to cancel because I would have missed my connection and there were no other flights for the next two days. They also lost my bag!!

Book cheap flights from Ontario to Illinois

Recent round-trip flight deals

5/20Mon
1 stopFrontier
10h 10mONT-STL
5/22Wed
1 stopFrontier
12h 19mSTL-ONT
$118
5/22Wed
1 stopFrontier
8h 43mONT-STL
5/23Thu
1 stopFrontier
16h 01mSTL-ONT
$124
6/4Tue
1 stopDelta
9h 04mONT-ORD
6/8Sat
2 stopsDelta
11h 27mORD-ONT
$251
6/5Wed
1 stopAlaska Airlines
7h 31mONT-ORD
6/18Tue
1 stopAlaska Airlines
17h 19mORD-ONT
$262
8/10Sat
1 stopDelta
7h 45mONT-MLI
8/14Wed
1 stopDelta
7h 12mMLI-ONT
$286
6/8Sat
1 stopAmerican Airlines
8h 03mONT-MLI
6/14Fri
1 stopAmerican Airlines
8h 36mMLI-ONT
$336
9/27Fri
2 stopsAmerican Airlines
8h 59mONT-STL
10/8Tue
1 stopAmerican Airlines
9h 09mSTL-ONT
$369
5/25Sat
1 stopUnited Airlines
5h 24mONT-MLI
5/28Tue
2 stopsUnited Airlines
20h 48mMLI-ONT
$477
8/14Wed
2 stopsUnited Airlines
7h 57mONT-PIA
8/21Wed
2 stopsUnited Airlines
8h 27mPIA-ONT
$508
6/11Tue
1 stopAlaska Airlines
10h 41mONT-STL
6/25Tue
2 stopsAlaska Airlines
11h 41mSTL-ONT
$525

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Recent one-way flight deals

5/22Wed
1 stopFrontier
8h 38mONT-ORD
$59
5/22Wed
1 stopFrontier
8h 38mONT-ORD
$60
5/29Wed
1 stopAlaska Airlines
7h 31mONT-ORD
$115
6/5Wed
1 stopDelta
7h 11mONT-MDW
$123
6/1Sat
1 stopDelta
9h 08mONT-ORD
$123
5/26Sun
1 stopAmerican Airlines
10h 55mONT-ORD
$133
5/28Tue
1 stopUnited Airlines
9h 00mONT-ORD
$160
5/13Mon
1 stopAlaska Airlines
7h 46mONT-ORD
$161
10/23Wed
1 stopAmerican Airlines
11h 59mONT-STL
$173
5/13Mon
1 stopUnited Airlines
8h 45mONT-ORD
$195

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Last minute flights from Ontario to Illinois

Last minute flight, train and bus deals

5/13Mon
multi-stopFrontier
8h 39mONT-MDW
5/21Tue
multi-stopFrontier
11h 14mMDW-ONT
$129
5/13Mon
multi-stopFrontier
12h 51mONT-STL
5/21Tue
multi-stopFrontier
15h 41mSTL-ONT
$132
5/10Fri
multi-stopAlaska Airlines
8h 25mONT-ORD
5/13Mon
multi-stopAlaska Airlines
9h 00mORD-ONT
$322
5/13Mon
multi-stopDelta
12h 24mONT-MDW
5/16Thu
multi-stopDelta
11h 26mMDW-ONT
$336
5/9Thu
multi-stopDelta
9h 20mONT-ORD
5/11Sat
multi-stopDelta
6h 24mORD-ONT
$337
5/13Mon
multi-stopUnited Airlines
5h 36mONT-ORD
5/14Tue
multi-stopUnited Airlines
8h 17mORD-ONT
$444
5/13Mon
multi-stopAmerican Airlines
7h 32mONT-ORD
5/16Thu
multi-stopAmerican Airlines
8h 44mORD-ONT
$527
5/13Mon
multi-stopUnited Airlines
8h 45mONT-ORD
5/16Thu
multi-stopUnited Airlines
7h 30mORD-ONT
$546
5/10Fri
multi-stopAlaska Airlines
8h 25mONT-ORD
5/13Mon
multi-stopAlaska Airlines
12h 29mORD-ONT
$723
5/10Fri
multi-stopAmerican Airlines
9h 41mONT-MLI
5/13Mon
multi-stopAmerican Airlines
8h 39mMLI-ONT
$778

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Ontario - Illinois Flights

Departure:

Ontario (ONT)United States

Return flight deals:

Illinois - Ontario

Cabin classes:

$404