$53 Find Cheap Flights from Ontario 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 Ontario to Illinois departing on 2/22. 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

Search 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 in flight searches from Ontario to Illinois, as well as popular online travel agencies
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Ontario to Illinois, as well as popular online travel agencies
In the last 7 days travelers have searched 41,299,237 times on KAYAK, and here is why:

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Best Illinois Flight Deals from Ontario

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

Chicago
Chicago1 stop$107
Moline
Moline2 stops$448
Peoria
Peoria2 stops$447
Springfield
Springfield2 stops$436
St. Louis
St. Louis1 stop$108

Good to know

Low season

February

High season

June

Cheapest flight

$53
Best time to beat the crowds with an average 25% drop in price.
Most popular time to fly and prices are also 4% lower on average.
Flight from Ontario to Chicago Midway Airport

FAQs - booking Illinois flights

  • How long is the flight to Illinois from Ontario?

    Flights to Chicago4h 07m
  • What is the cheapest flight to Illinois from Ontario?

    The cheapest ticket to Illinois from Ontario found in the last 72 hours was $53 one-way, and $107 round-trip. The most popular route is from Ontario to Chicago Midway, and the cheapest round-trip airline ticket found on this route in the last 72 hours was $53.

  • Which airlines fly to Illinois?

    Southwest flies most frequently to Chicago Midway from Ontario.

  • 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 from Ontario to Illinois 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 from Ontario 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 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 from Ontario to Illinois 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

  • Book at least 1 week before departure in order to get a below-average price.
  • High season is considered to be January, February and December. The cheapest month to fly from Ontario is February.
  • Morning departure is around 3% cheaper 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

 
See real verified KAYAK customer reviews for airlines flying from Ontario 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 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.
8.1
SouthwestOverall score based on 4821 reviews
8.2Boarding
8.1Comfort
7.7Entertainment
8.7Crew
7.2Food
Airline reviews

I recently flew Southwest from San Jose to Honolulu. I was very impressed with the flight crew, especially the flight attendant in charge of the front of the plane. She came through the aisle at least five times for drinks and water, and two times for snacks. I have not seen such service since I flew first class. Also, for the first time, they gave us the correct baggage claim number, and the luggage came out quickly. I can't wait for Southwest to have assigned seating! I absolutely hate the Cattle Call boarding procedure and the mad dash to get seats and overhead bins. However, the boarding was efficient.

10.0 ExcellentWilliam Drew, Dec 2024SJC - HNL
Read more Southwest reviews

I recently flew Southwest from San Jose to Honolulu. I was very impressed with the flight crew, especially the flight attendant in charge of the front of the plane. She came through the aisle at least five times for drinks and water, and two times for snacks. I have not seen such service since I flew first class. Also, for the first time, they gave us the correct baggage claim number, and the luggage came out quickly. I can't wait for Southwest to have assigned seating! I absolutely hate the Cattle Call boarding procedure and the mad dash to get seats and overhead bins. However, the boarding was efficient.

We had a nice flight. Boarding was easy, our seats were comfortable and the on board service was pleasant.

Service was great, boarding and exiting went smoothly, and the flight was very pleasant.

Was as expected. Crowed planes. Too many carryons delaying takeoff. But the ride only took an hour and saved me a lot of time SFO is a not a great airport.

Was as expected. Crowed planes. Too many carryons delaying takeoff. But the ride only took an hour and saved me a lot of time SFO is a hell hole of an airport. It is the new LaGuardia. Everything Cobbled together. Security gates closed. Terri directional signage

I used to fly SWA all the time. I know the crew has their little acts that are often fun, and entertaining. On this flight one of the crew was just not nice. Very surprising.

I like that it was on time and the staff was friendly.

The plane arrived 25 minutes late, and the Wi-Fi was slower than it usually is.

Forget beverage, they didn't even have water for half the passangers?

Can not wait for seating change to reduce the amount of pre boards - it’s disheartening the abuse. And then then deplaning

It was terrible, if they ran flights on time it would make a big difference.

Delta seems to be improving in many areas, except they are super bad with the food available. Bring back normal food service on long flights.

I actually received a notification from kayak on email but not one by text from Delta when my departure gait changed and I almost missed my flight

New boarding doesn't make sense. Filling front first is slow.

Delta flight was great from the check in all the way to arrival. However, I had a very bad experience. I requested a wheelchair and the wheelchair employee that went to pick me up from the plane in Boston to bring me to the baggage claims told me I have to pay him. I was under the impression that it was a free service and I usually give tips but the person forced me to pay and since I said no because I was upset with his demand when my daughter walked in to pick me up he demanded payment from my daughter who paid him thinking maybe now it is a charged service.

Horrible. Grateful to be alive but spent 13 hours at airport only to return back to my familys house and flight changed to next day. They tried to fix a part on plane, had no back up plane and after 10 hours , reattempted the flight and it STILL wasn't fixed. We got a meal voucher and rescheduled flight but there should be some other compensation for the 15 hours spent in airport

5 hour delay. They blamed the weather but it was the computer issues they had been dealing with for days.

My seat was changed at the last minute and I was moved to the last row, right next to the bathroom despite selecting my seat well in advance. I was also made to check my carry on due to space but when I got on the plane there was significant empty overhead space. Picking up my carry on from the luggage carousel added time to my trip which had already been extended due to delay.

There was plenty of overhead room but half of the passengers were told they had to check their carryon bags. My partner and I checked in as early as possible and our seats were split across the aisle.

Flew first class so everything was great. But maybe because the flights were red eye, no meals were served, just chips. I flew Alaska Air 1st class at 9PM (2 hour flight) and they served beef short rib sliders!

They canceled our flight and left us stranded to figure it out

Everything was very good. Was able to change a make run flight leaving on direct earlier in the app -seamless!!! Well done

Being stick waiting for gate at ORD cause me to almost miss my connecting flight…being deaf United made no no effort to keep me updated as I couldn’t hear the PA

As usual, United scheduling is completely misleading. A 54-minute layover at O’Hare is too short to make a lot of connections, especially since the flight landed “on time” but had to wait on the taxiway 15 minutes for a gate to open up. Then it takes another 10 minutes to exit the plane before one can run to another concourse to catch a connecting flight.

The seats on the aircraft are like sitting in a rock. During the boarding process they recognize Active Duty Military, why don’t they recognize Retired Military. I’ve always preferred Delta, this flight confirmed why I still prefer Delta.

when you can say you don't remember being at any point upset during a flight, the airline is winning .

The staff was very friendly. The seats seemed quite small. Overall the flight was pleasant.

It was literally one of the worst travel experiences ever. My flight got delayed by over an hour and there was no communication of this from the gate staff. I realized it by checking the screen periodically. Once on board the flight attendants continued to serve alcohol to a man who was clearly already drunk and that was making a bunch of commotion. Never again will I fly United!

Charging and entertainment didn't work. The meal was horrible. They only came by with the drink cart one time for the 8 hour flight. They did come by with water a couple times.

Exceptional, I’d like to specifically recognize Robert for his outstanding customer service. He is professional, pleasant, and personable.

Other than being delayed 5.5 hours and having to get a hotel because I missed my connecting flight, it was an okay flight. No in-flight Wi-Fi or entertainment.

It was nice being on a flight that had working wifi. The boarding was quick - why don’t all airlines have small boarding groups window to aisle? Makes so much sense!!! I was disappointed to be the first person stopped to have to gate check my carryon. Especially when there was plenty of overhead space at the back! But I get it…keeps it moving. Crew was nice.

The flight from Buffalo to Chicago was on an older and smaller plane. Seating was tight. Looking closely at the interior of the aircraft there were definitely signs of aging and wear.

The flight encountered a delay exceeding 4 hours. The food voucher issued was valued at $12, insufficient to cover our meal expenses. Consequently, I was unable to take my medication, leading to a drop in blood sugar levels and exacerbating my anxiety.

Airplane was cold. Flight attendants were rude. Phone charger did not work. No food available.

3hour delay In the last 3 months i had 3 flights and 2 of these had a more than 2:40 hrs delayed

My initial flight to ORD was extended without reason. We circled the airport a few time and then drove on the ground for at least 20 minutes. These kinds of delays are annoying but somewhat expected… it would be nice if the crew would make an announcement to give updates on how long we could expect to be delayed.

The flight was uneventful. What was a problem was I was delayed getting home one entire day because the flight from Sacramento was delayed. That made getting to my connecting flight impossible. I had to stay another night at the hotel and incur that expense as a result.

VERY disappointed at the agent checking in my luggage. I know that the weight limit is 23 kg, a little over 50 pounds (50.71 pounds). Yet the agent kept repeating "50 pounds". So I said, the limit is 23 kg, and she had the audacity to say 'no, it is 22 kg!" Imagine my surprise. Was she ignorant or was she poorly trained? Not sure. The boarding process was pretty good. The speakers were loud enough so I still could hear them despite inconsiderate passengers continuing to speak while the announcements were going on. During the flight, the teenage girl sitting behind me kept pressing her feet to the back of my chair. I turned around several times, yet she did not get the hint. I did not make a fuss since I sense I had a bad streak that night with AA, so I just did the best I can to lean forward and not let that bother me.

This flight was fine but had no time to breathe as the connection was late from Sea to ORD.. Super stressful. If we checked bags, the trip would have been very distressed.

The takeoff was the smoothest I've ever experienced on any airline and this is the first time I've flown on frontier so this was an extremely pleasant surprise!

A lady asked to stop the flight after the tunnel pulled away and we began to depart a flight that was already hours late. The attendance respectfully stopped the the plane and had the tunnel return. After the tunnel returned the passenger claimed to have changed her mind . The tunnel was then put in reverse and the passenger remained on the plane .. They should have sent the sick passenger off the plane like initially replaced. They existed a couple off the plane prior to that situation.. So.. all and all.. it was a long and flight.. .

terrible cascading delays and unhelpful customer service. uncomfortable plane. crew was great, however!

With frontier you get what you pay for. The flight was two hours late. It’s a tight fit for the number of people they bring but you get to where you’re going cheap. Sometimes that’s more important than a nifty drink and cool TV..

Charges unexpected. For seat that didnt recline. Please reverse extra seat and carryon charge. Bad business that is a bait and switch.

We had an awful experience getting our bags checked in. Frontier’s check in on the app manipulated us into buying the business package because that was the only option available for a checked bag which included two checked bags per person which we did not need. Upon arriving to the airport, we stood in line for what seemed like forever at the baggage check in and there was no one available at the counter. We were first in line and we were afraid we were going to miss our flight due to the baggage attendant being late. After realizing there were a lot of other people waiting at the baggage check in and no one available. I reached out to Frontier and could not get any customer service so I had to call the airport to page the baggage attendant to send someone to the counter to check in our bags before we were able to go through security , I finally spoke to the attendant at the counter and explained to her that we had to pay for two checked bags person a total of six bags when we only had a total of three bags between three people she said to reach out to Frontier and they would issue a refund for the three bags that we paid for and did not need. I reached out to Frontier which I was not able to reach anybody by phone so I had to go through their automated chat feature, which sent me around in circles until I finally reached a representative to assist me. I explained to them what happened and they explained that they were not able to assist me. I continued to push the issue with them as this was very frustrating and they finally put in a customer service ticket where we were issued a flight credit and we were so disappointed because after this experience, we NEVER want to fly Frontier again, and we do not want a credit that we will not use. Frontier charged us almost $500 for us to check three bags which is absolutely absurd! The customer service agents were not able to offer anything else other than a flight credit and I do not feel like my frustrations were truly heard , we will never use Frontier Airlines again ! Truly Theft by Manipulation! They should be ashamed!

I couldn’t check in because the app didn’t work. It took 3 Frontier employees at the counter to get me checked in. Flight left 3 hours after departure time

While booking it was not obvious that I had to pay for carryon. Realized it only during check-in. Overall, meh!

Stop changing gates at sfo. When you are elderly going back for it’s not fun.

We understand and comply with Frontier’s bag sizes. We’ve had some problems in past while having to await other passengers who do not understand the baggage restrictions or have not prepaid and that is usually our biggest concern (others delaying us) with flying Frontier. Flying OUT of ONT, however, has always been a great experience. I’ve also noted even on delayed Frontier flights very knowledgeable pilots who manage expectations well.

Book cheap flights from Ontario to Illinois

Recent round-trip flight deals

 
These are the cheapest round-trip flights from Ontario to Illinois found on KAYAK in the last 72 hours.
1/9Thu
1 stopFrontier
15h 28mONT-MDW
1/15Wed
1 stopFrontier
17h 29mMDW-ONT
$107
1/30Thu
1 stopFrontier
9h 35mONT-STL
2/5Wed
1 stopFrontier
6h 38mSTL-ONT
$108
1/9Thu
1 stopAmerican Airlines
7h 41mONT-ORD
1/15Wed
1 stopAmerican Airlines
7h 58mORD-ONT
$136
1/28Tue
1 stopAmerican Airlines
6h 28mONT-ORD
2/5Wed
1 stopAmerican Airlines
7h 08mORD-ONT
$226
1/18Sat
1 stopDelta
7h 20mONT-MDW
1/25Sat
1 stopDelta
9h 11mMDW-ONT
$256
1/22Wed
1 stopDelta
6h 01mONT-ORD
1/28Tue
1 stopDelta
7h 11mORD-ONT
$256
4/7Mon
1 stopUnited Airlines
6h 25mONT-ORD
4/13Sun
1 stopUnited Airlines
10h 20mORD-ONT
$323
2/21Fri
nonstopSouthwest
3h 45mONT-MDW
2/25Tue
nonstopSouthwest
4h 30mMDW-ONT
$330
4/17Thu
1 stopUnited Airlines
6h 25mONT-ORD
4/19Sat
1 stopUnited Airlines
9h 20mORD-ONT
$336
1/28Tue
nonstopSouthwest
3h 45mONT-MDW
1/31Fri
1 stopSouthwest
8h 35mMDW-ONT
$359

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Recent one-way flight deals

 
Only flying one-way? Below are some of the best one-way flight deals from Ontario to Illinois found on KAYAK in the last 72 hours.
2/22Sat
1 stopFrontier
7h 02mONT-MDW
$53
2/6Thu
1 stopFrontier
7h 29mONT-ORD
$53
1/19Sun
1 stopAmerican Airlines
7h 29mONT-ORD
$68
1/18Sat
1 stopAmerican Airlines
6h 28mONT-ORD
$124
2/12Wed
1 stopDelta
7h 20mONT-MDW
$128
1/18Sat
2 stopsDelta
9h 47mONT-MDW
$133
2/12Wed
nonstopSouthwest
3h 45mONT-MDW
$160
1/14Tue
1 stopSouthwest
11h 45mONT-ORD
$164
3/11Tue
1 stopUnited Airlines
8h 43mONT-ORD
$168
2/18Tue
1 stopUnited Airlines
7h 11mONT-STL
$204

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Last minute flights from Ontario to Illinois

Last minute flight, train and bus deals

 
These last-minute flight deals are the cheapest flights found on KAYAK in the last 72 hours for flights from Ontario to Illinois that are departing in the next 10 days.
12/24Tue
multi-stopFrontier
20h 47mONT-ORD
1/31Fri
multi-stopFrontier
12h 03mORD-ONT
$269
12/24Tue
multi-stopFrontier
18h 33mONT-MDW
1/4Sat
multi-stopFrontier
13h 28mMDW-ONT
$274
12/20Fri
multi-stopDelta
7h 25mONT-MDW
12/23Mon
multi-stopDelta
8h 38mMDW-ONT
$518
12/21Sat
multi-stopDelta
9h 53mONT-ORD
12/23Mon
multi-stopDelta
7h 24mORD-ONT
$518
12/25Wed
multi-stopUnited Airlines
5h 43mONT-STL
12/31Tue
multi-stopUnited Airlines
6h 06mSTL-ONT
$548
12/25Wed
multi-stopUnited Airlines
6h 10mONT-ORD
1/2Thu
multi-stopUnited Airlines
6h 41mORD-ONT
$599
12/23Mon
multi-stopSouthwest
6h 55mONT-ORD
12/25Wed
multi-stopSouthwest
8h 30mORD-ONT
$613
12/23Mon
multi-stopSouthwest
9h 40mONT-ORD
12/25Wed
multi-stopSouthwest
8h 30mORD-ONT
$618
12/24Tue
multi-stopAmerican Airlines
7h 22mONT-STL
12/26Thu
multi-stopAmerican Airlines
6h 59mSTL-ONT
$926
12/22Sun
multi-stopAmerican Airlines
7h 35mONT-STL
12/26Thu
multi-stopAmerican Airlines
8h 28mSTL-ONT
$931

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Everything you need to know for your flight from Ontario to Illinois

Information on your arrival and departure airports

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