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Cheap Flights from Ontario to Illinois

Cheapest round-trip prices found by our users on KAYAK in the last 5 days
Chicago
Chicago1 stop$271
Moline
Moline1 stop$395
Peoria
Peoria1 stop$479
Bloomington
Bloomington1 stop$687
Springfield
Springfield1 stop$489
Chicago
Chicago1 stop$271
Moline
Moline1 stop$395
Peoria
Peoria1 stop$479
Bloomington
Bloomington1 stop$687
Springfield
Springfield1 stop$489
Booking Insights

Price, demand and travel trends for Ontario to Illinois flights

Use KAYAK data on prices, travel dates, airlines and seasonal trends to compare options and book flights with more confidence.

What are the cheapest fares from Ontario to Illinois recently?

The cheapest fares from Ontario to Illinois on KAYAK in the last week were to Chicago Midway (MDW) from $271 round-trip and to Chicago O'Hare Intl (ORD) from $271 round-trip.

How do fares into airports in Illinois compare?

According to KAYAK data from the last 12 months, the cheapest airports to fly into Illinois from Ontario are:

• Bloomington-Normal (BMI) (avg. price $378)
• Chicago O'Hare Intl (ORD) (avg. price $426)
• Chicago Midway (MDW) (avg. price $443)

Are flights from Ontario to Illinois cheaper or more expensive than last year?

Fares from Ontario to Illinois are about 4% lower than they were in November last year, averaging $410 round-trip.

What's the cheapest month to fly from Ontario to Illinois?

October is typically the cheapest month to fly from Ontario to Illinois, with round-trip fares averaging $382. April and June are usually the most expensive, averaging $484 and $480, respectively.

How do fares from Ontario to Illinois vary by day of the week?

On average, Tuesday is the cheapest day to fly from Ontario to Illinois and Sunday is the most expensive. Looking at the past 12 months of KAYAK data, it's 36% more expensive to fly on a Sunday compared to Tuesday.

What's the best time of day to fly from Ontario to Illinois?

It's cheapest to fly to Illinois in the evening with average prices of $292. The morning is the most expensive time to fly, with average prices of $464.

What's the best time to book a flight from Ontario to Illinois?

Book your flights 9 weeks before your trip. KAYAK data collected over the past 12 months shows that booking in this window can save you around 23% compared to booking at the last minute (within 2 weeks of departure).

Key details for Ontario to Illinois flights

Low season

February

Cheapest flight

$113
Beat the crowds with an average 61% drop in travelers.
The most popular month to fly with an average 55% increase in travelers.
One-way flight from Ontario to Chicago O'Hare Intl Airport

Your Ontario to Illinois flight questions, answered

Find helpful answers about this route, including flight times, airports, airlines and booking tips.

  • Is now a good time to book a flight from Ontario to Illinois?

    Yes. Fares from Ontario to Illinois are low right now. As a rule of thumb, a round-trip under $342 (cheaper than most fares this year) is a good deal, so if you spot one at or below that, it's a good time to book.

  • How much should I budget for a flight from Ontario to Illinois?

    Over the past 12 months, round-trip fares from Ontario to Illinois have typically cost between $342 and $549.

  • What are the main airports serving Illinois?

    There are 17 airports in Illinois. 76% of KAYAK users choose Chicago O'Hare Intl (ORD) as their arrival airport, while 21% choose Chicago Midway (MDW).

  • Which airlines fly nonstop from Ontario to Illinois?

    Based on the flight schedule for the next 3 months, 3 airlines offer nonstop flights on this route:

    • Southwest
    • United Airlines
    • American Airlines

  • Which destinations in Illinois can I fly nonstop from Ontario?

    Based on the flight schedule for the next 3 months, you can fly nonstop from Ontario to just one destination in Illinois: Chicago.

  • Is it cheaper to fly with a layover from Ontario to Illinois?

    Yes, nonstop flights from Ontario to Illinois average $461 over the past 12 months, but flights with a layover can cost less. The most affordable connecting airports are:

    • Houston George Bush Intcntl (IAH) (avg. price $288)
    • Seattle/Tacoma Intl (SEA) (avg. price $324)
    • Denver Intl (DEN) (avg. price $343)

  • How long is a flight from Ontario to Illinois?

    Nonstop flights from Ontario to Illinois take 3h 56m on average. The fastest scheduled flight takes 3h 45m, flying into Chicago Midway (MDW).

  • Which cabin classes are available from Ontario to Illinois?

    On flights from Ontario to Illinois you can book Economy Class, Premium Economy Class or First Class.

  • What are some popular landmarks around Illinois?

    Illinois is home to many popular sights. KAYAK travelers' favorites include:

    • Magnificent Mile
    • Grant Park
    • Soldier Field
    • River North

  • What are the earliest and latest flights from Ontario to Illinois?

    The earliest nonstop flight from Ontario to Illinois departs at 5:20 am and the latest leaves at 11:55 pm. Nonstop flights take about 3h 56m.

Your guide to booking Ontario to Illinois flights

Get tips on when to book, when to fly and what to know before your trip.
  • If you can plan ahead, the sweet spot for booking your flight is 9 weeks before your trip. KAYAK data shows fares in this window are around 23% lower than last-minute bookings (made within 2 weeks of departure). Not ready to commit? Set a Price Alert and we'll let you know when prices change.
  • Flexible with your dates? Fly in October to save some money. It's typically the cheapest month on this route, while flights in April will cost you the most.
  • Fly out on a Tuesday to get the cheapest fares. Avoid Sunday flights, which are about 36% more expensive.
  • If you're watching your budget, fly into Bloomington-Normal (BMI) which has the lowest average airfare in the region. Just remember to budget for any onward travel by bus, car or domestic flight.
  • Start your trip in Chicago, the most popular destination in Illinois. From there, it's easy to continue on to other popular spots such as Rosemont, Schaumburg and Champaign.
  • Time or money? If speed matters most, fly from Ontario to Chicago Midway (MDW). If you're after the lowest fares, Bloomington-Normal (BMI) is usually your best bet.

Reviews of the 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.
8.0
SouthwestOverall score based on 4220 reviews
8.0Comfort
8.6Crew
7.5Entertainment
7.0Food
8.1Boarding
Airline reviews

Delayed over 3 hours, extremely rough landing on all four flights. Would not recommend

2.0 MediocreKevin, Oct 2026
Read more Southwest reviews

Delayed over 3 hours, extremely rough landing on all four flights. Would not recommend

The entire crew were wonderful but 1 flight attendant stood out with his sense of humor on the microphone. I told him as much as I exited the plane.

Maybe different snack selection. To much sodium in them. I know refrigerators are not available but there has to be healthier items.

Wasn't expecting this, but, we actually ended up getting assigned to the first row of seats!!!!! The extra legroom came in handy

Flight was delayed, full flight and I had to change gates. Southwest flights are always late later in the day.

Flight was delayed over 3 hours. Planes were dirty. Staff indifferent. And they serve vegan pretzels as snacks.

The flight was smooth. The Southwest experience has degraded overall, but this one was okay.

Flight was ok. Boarding wasn’t fun. Flights were delayed by 12 minutes on each leg.

Wifi didn’t work, no service, seats are hard as rocks

I liked receiving attention from aged and well experienced flight attendants. I disliked the non-gluten-free snack but I brought my own so I was OK.

Chairs don’t recline and the ones that do recline, barely do recline. It was most uncomfortable flight i ever been on.

Requested an aisle seat at the gate and got it. The staff so friendly

Flight was very delayed so I was able to get on an earlier flight via stand-by. Crew communicated effectively around delay and worked to make customers comfortable. Wifi was ok, streaming TV was great. App functionality broke down once I was moved to stand-by on earlier flight.

Sat in the tarmac at O’Hare for 65 minutes. This is a regular occurrence for delta at O’Hare

It was as good as it could be. Flying is not a pleasant experience these days.

It was a great flight and the stewards and stewardess were all kind and accommodating!! The seats were comfortable and entertainment screen excellent!

737-800 in first class was pretty dumpy. Seat had an uncomfortable angle, storage under the seat was blocked so even my very modest backpack didn't fit, power outlet was flaky. Weird tiny seat pockets that couldn't hold a gallon ziploc bag, emesis bag missing, etc. etc. No in-flight service due to turbulence. Crew was excellent, boarding was smooth despite a full flight.

The flight was overbooked and the staff at the gate started calling for volunteers to drop out and offering incentives. That delayed the flight

There was no wifi even after my husband paid for wifi it wasn’t working. The plane looked and felt old.

Update the cabin with tv screens or at least music sources.

Better management of the boarding process. Is there any way you could forward all the window seats first? That's the Way Reno Air used to do it, and they had the fastest boarding in the industry!

We were delay because so many bags needed to be gate checked and it was disappointing not to have outlets in the seats for such a long flight.

Excellent. I had a medical emergency on flight SNA-ORD and the attendants were very helpful.

Seat pitch is horrible especially on the 15 hour flight. Gate crew at SFO was Outstanding. The flight crew was also great.

Crew was great (professional, attentive, prompt). Snacks for 4 hrs flight is deplorable.

It was a pretty standard flight... until the almost hour and a half spent on the taxi way. I get that the weather has been poor but the delay had nothing to do with the weather and more to do with a plane with several issues tying up the gate. I get that that happens from time to time but this has been EVERY flight I've been on for the past 5 years and I fly 3 to 5 times a year. This isn't just United... it's American, it's Delta. It's an issue with the entire industry. I work for UPS and packages on a cargo plane get better service than people do these days. Anymore I HATE flying.

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.

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.

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

All good. Easy check in and boarding. Lovely flight crew

No food on 4.5 hour flight, wi-fi did not work. Terrible experience for a long haul flight.

first leg from san diego to chicago, only had cookies for snack. 1 flavor of sparkling water chicago to washington dc had option of cookies, pretzels, or gold fish. had 2 flavors of sparkling water. 2nd flight better however the best part was there was no delays!!! Got to chicago and washington dc early. That was wonderful!!!!

American was the airline that Starlux contracted for this trip. I arrived in time to make the connecting flight on American, and then the baggage-handler debacle happened. For some reason, the first class and premium economy passengers' luggage was unloaded first. Never seen this happen before. They had handlers removing the bags from the carousel for those passengers. Meanwhile, all of the economy passengers were waiting for their bags, including me. And there were a lot of bags because it was an international flight packed full. While waiting for 45 minutes, my bag didn't show. Meanwhile, an American representative showed up asking if anyone has a connecting flight to Phoenix. Of course I spoke up, and they proceeded to try to find my bag because I had to take a bus to the actual terminal to catch my flight. Which I was not informed of before I arrived. After another 15 minutes of searching, my bag was finally found with the first-class passengers' bags because they had pulled it by mistake. So I rushed to the terminal with the American representative to catch my flight, and they informed me that I missed it and could not get another flight until the next day. Of course, after being on an international flight for 18 hours, I was in no mood to hear this. Now, to be fair, there were a few American employees who tried to help me. After hearing about the missed flight, they got a supervisor to talk to. I expressed my situation to the supervisor, and she was not helpful until I asked for compensation. She agreed to get me a hotel room for the night. So I agreed, and she disappeared into her office, and I waited. And waited. And waited. And waited. While waiting, I was asked by three different employees who knew of my situation if I had been helped. I told them I was waiting for the supervisor to get the hotel room, and they said they would check. Finally, after waiting for 75 minutes, one of the employees who had asked me if I had been helped arrived with my hotel room and arranged a ride to the hotel for me. Never saw the supervisor again. It was now 8 o'clock; I arrived at 5:45! My rebooked fight was scheduled for 6:11 this morning and I have now been informed it has been delayed until 10:00. So am I happy with American? NO I'M NOT!! ;

Ontario airport boarding was very easy to park and access, is clean and TSA took 10 minutes total. Check-in was a breeze and cruise was very nice.

Good flight, seated and had a water within 5 minutes. Crew was hospitable.

The flight was on time and arrived early. The crew were friendly and helpful.

The chair cushions may need an upgrade. I have been noticing they are so worn out, thin so you’d sit in a dip 😄. Other than that, all was an enjoyable trip. Thanks AA!

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.

It was wonderful upgrading to first. Plane was so cold thou. Crew was great. Wish there was a food option in first for such a long flight. Doesnt matter the time of day. Chintzy.

Maximizing profits is one way to a healthy bottom line, the other is repeat business and referrals from satisfied customers. Frontier has clearly chosen the former. One of many examples: Family emergency required me to cut trip short. Headed to the airport to fly standby for the return trip I had already paid for (yes I understand prices vary with demand etc). Was told there is no standby and that I would need to pay for, despite what it's called by the company, what amounts to a new ticket. And surprise surprise, there turned out to be dozens of empty seats on that flight. To say nothing of the sleazy third and fourth party resellers, the flight/ticket insurance I elected and thought I had paid for that mysteriously wasn't there when I needed it before I left, and on and on with third world sleazy management decisions. The inflight coffee (that I had to pay for) was very good though.

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.. .

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.

Long lines, rude staff, everything that's offered you have to pay for.

The last time I flew Frontier was in the 1960s when it was a “real” airline. We flew this time because of the price & schedule. As the saying goes, you get what you pay for.

I appreciated the upgrade to free cary-on bag and seat selection at no charge

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

This isna terribly run airlines. If you're one minute late, they will deny your ticket. Don't waste your time or money

Flight was delayed for more than 3 hours, crew at ONT airport was rude, and when we got to DFW the airplane had an issue landing, we had to be taxied to the terminal, and the luggage was hold until the next day.

More options for your flight from Ontario to Illinois

Complete your trip to Illinois with a hotel stay or car rental