$104 Find Cheap Flights from Ontario to Illinois

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Good to know

Low seasonJanuary
Cheapest flight$104
Best time to beat the crowds but there is an average 6% increase in price.
Most popular time to fly with an average 6% increase in price.
Flight from Toronto Pearson Airport to Chicago O'Hare Airport

Flights from Ontario to Illinois: the best tips from KAYAK users

Insights shared by verified travelers who flew the route from Ontario to Illinois 
BrianFlew with Air CanadaYYZ-ORDOct 2024
Be prepared for a labyrinthine experience traversing the various levels and passages of the Toronto airport. Bring quality walking shoes, as it is likely well over a km in total walking time.
Verified travelerFlew with United AirlinesYYZ-ORDMar 2024
Carry-on baggage sizing for United US bound flights appears to be much smaller than for Canadian flights, which forced me to check my bag at the last minute. So check online ahead of time

FAQs for booking flights from Ontario to Illinois

  • 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.

  • Which airlines fly most frequently to Illinois?

    Ontario and Illinois are connected by different airlines. The airlines that fly that route the most regularly are United Airlines (110 flights per week), Air Canada (105 flights per week), and Air New Zealand (68 flights per week).

  • How many airports are there in Illinois?

    There are 12 airports in Illinois. The busiest airport is Chicago O'Hare Airport (ORD), with 93% of all flights arriving there.

  • Which is the cheapest airport to fly into in Illinois?

    Prices will differ depending on the departure airport, but generally, the cheapest airport to fly to in Illinois is Chicago Midway Airport (MDW), with an average flight price of $194.

  • What is the cheapest day to fly to Illinois?

    Based on KAYAK data, the cheapest day to fly to Illinois is Saturday where round-trip tickets can be as cheap as $450. On the other hand, the most expensive day to fly is Monday, where round-trip prices are $719 on average.

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

    The cheapest time of day to fly to Illinois is generally at night, when round-trip flights cost $394 on average. Morning departures are around 19% cheaper than evening flights, on average. The most expensive time of day to fly to Illinois is generally in the evening, which is peak travel time and where the average cost of a ticket is $617.

  • What is the cheapest flight to Illinois?

    The cheapest ticket to Illinois from Ontario found in the last 72 hours was to Chicago O'Hare Intl Airport, at $164 round-trip. The most popular route is Ottawa (YOW) to Chicago O'Hare Intl Airport (ORD) and the cheapest round-trip airline ticket found on this route in the last 72 hours was $164.

  • What is the cheapest month to fly from Ontario to Illinois?

    The cheapest month for flights from Ontario to Illinois is December, when tickets cost $302 (return) on average. On the other hand, the most expensive months are March and September, when the average cost of round-trip tickets is $720 and $434 respectively.

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

    To get a below average price on the flight from Ontario to Illinois, you should book around 4 weeks before departure, which saves you about 46% compared to booking last minute. For the absolute cheapest price, our data suggests you should book 12 weeks before departure.

  • How many cities have direct flights to Illinois?

    From Ontario, there are direct flights to Illinois from 2 cities. The city with the most direct flights is Toronto, with 452 direct flights each week.

  • How many direct flights to Illinois are there each day?

    There are around 77 direct flights from within Ontario to Illinois every day. Most flights (47%) depart in the morning.

  • How many direct flights to Illinois are there each week?

    Each week there are around 536 direct flights from within Ontario to Illinois. The most common day for departures is Sunday, with 15% of flights taking off on this day.

  • How long is the flight to Illinois?

    An average nonstop flight from Ontario to Illinois takes 7h 47m, covering a distance of 605 miles. The shortest route is Toronto Island Airport (YTZ) to Chicago Midway Airport (MDW) with an average flight time of 1h 49m.

  • How many long-haul flights are there to Illinois each week?

    There are not any long-haul (6-12 hour flight duration) or medium-haul (3-6 hour flight duration) flights to Illinois. Instead, there are 536 short-haul flights (up to 3 hour flight duration), with the most arriving from Toronto.

  • What are the most popular destinations in Illinois?

    Based on KAYAK flight searches, the most popular destination is St. Louis (88% of total searches to Illinois). The next most popular destinations are Peoria (5%) and Decatur (3%). Searches for flights to Champaign (1%), to Moline (1%) and to Bloomington (1%) are also popular.

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.
7.9
Porter AirlinesOverall score based on 346 reviews
7.6Food
7.0Entertainment
8.0Comfort
8.6Crew
8.2Boarding
Airline reviews

I was not happy with AirfareAssist, the agency that kayak advised me would be handling my booking. I was advised by porter airlines that I had been overcharged for the Basic express , a option that I had asked airfare assist to help arrange after I realized that the basic fare I had chosen with porter did not include a carryon. At each checkin porter advised I had been overcharged for this . They advised that money would be refunded to my credit card, however, this is not likely to happen as it is not my name and credit card that appeared on the porter invoice, but that of another individual/agent. When airfare assist was arranging the basic express with porter on my behalf, they asked me to confirm that I agreed to pay $263 USD for this. I did agree, as I was advised this was needed to proceed. When I checked the invoice on the porter website and saw that it was not my name and credit card on the invoice, I was advised that this was how airfareassist processed the payment. The Porter invoice indicated a billed amount of $126USD I will not use Kayak or their designated AirfareAssist again

6.0 GoodAnonymous, Aug 2025YYG - YYZ
Read more Porter Airlines reviews

I was not happy with AirfareAssist, the agency that kayak advised me would be handling my booking. I was advised by porter airlines that I had been overcharged for the Basic express , a option that I had asked airfare assist to help arrange after I realized that the basic fare I had chosen with porter did not include a carryon. At each checkin porter advised I had been overcharged for this . They advised that money would be refunded to my credit card, however, this is not likely to happen as it is not my name and credit card that appeared on the porter invoice, but that of another individual/agent. When airfare assist was arranging the basic express with porter on my behalf, they asked me to confirm that I agreed to pay $263 USD for this. I did agree, as I was advised this was needed to proceed. When I checked the invoice on the porter website and saw that it was not my name and credit card on the invoice, I was advised that this was how airfareassist processed the payment. The Porter invoice indicated a billed amount of $126USD I will not use Kayak or their designated AirfareAssist again

Our flight was delayed by a bit. I appreciated that we were kept informed on why periodically. Boarding was fine. I overheard one flight attendant sounding very rude to a passenger who was not paying attention to the safety demonstration. The snacks were minimal as it was a short flight. There was no entertainment. Overall the flight was good back to LGA.

The flight was fine see earlier note for the problem

Three hours on the tarmac with almost zero communication from the cockpit. Not when offered a water in the interim. In my 67 years of flying all over the world the worst experience ever. The plane was half empty, however had to pay for seats to sit next to my girlfriend. Extra to take a carry on. I would never fly Porter again even for free.

All good the seats a little tight and no I pad screen

Everything was good except the fact you charge more for a carry on bag vs a check in bag and to top it off in US$ that was not impressive

Our flight was cancelled at the last minute for maintenance reasons and we were rebooked on a late flight when we purposefully booked our flight to be home early due to work.

Seemed like an old plane. Very noisy. The seat cushions were so old that the metal bracing of the seats were poking through. There was plenty of leg room though.

Flight was delayed over 2 hours, then landed at a different airport!

The whole experience from check in to deboarding was fantastic.

It’s ok just the boarding point is far too far

Check in slow even though completed online check in, there was no bag drop available so had to query for 90mins as only 2 staff on desks.

Flying to a far away destination is a miracle in itself, so please take these with a grain of salt. The seats are a bit tired, and need a freshen up. The entertainment could be a bit newer, especially with all services available now. The food really is where we need help. But again, flying is a privilege, so all is good.

Not so much porter it's your site! Not good

They are a sister company with Air Transat and the two companies do not work well together. If you have any issues the two companies will blame each other and you will miss your flights. The help line does not help

Never book through a third party. Book through Air transats website. Terrible process to get help and many issues happen with them and sister companies because half the flights you book with them aren’t even through air transat.

The plane was pretty full, and we dis not have any includes meal for our 4h30 flight? And on-board entertainment wasn't available, there was no TV or plugging to charger your device on the plane. They told us to download an app if we wanted to watch movies but it never connected, that was a disappointment, the r we st was very good though and the crew were really nice!

Seats were very tight especially for first leg of trip.

Not necessarily a Transat issue but it took 2 hours to go through immigration. Tried to reach out to Transat for resolution but was unable to reach an agent.

The flight was excellent, once it started, however we were delayed two hours when the first plane’s engines wouldn’t start. They found another identical plane and transferred us and our luggage in under two hours and made up almost an hour in the air.

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 all good flight was on time, service was good I enjoyed a few movies and everything was smooth

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!

Good service, friendly staff. Food was average for airlines and the seats were small.

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..

Horrible flight cancelled had to buy another very expensive ticket

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

Terrible, return flight was cancelled a night before the flight was scheduled to depart and I was notified by an email and an automated message on their phone line. I’ll never book Air Canada again

Biggest problem for me is that I am Star Alliance Gold and they were not able to give me access to to Maple Lounge because of some computer glitch . It was management by information system. She could clearly see my status and still would not give me access because the computer woudl not let her. She should have override that be attentive to a customer and figure rhat out later

Great breakfast and coffee …..fastest bag service I have ever had in NOLA

Late departing. Late arriving. More worried about limiting bags on board. Free beer and wine a nice surprise.

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

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.

Everything you need to know for your flight to Illinois

Cabin class types available on flights to Ontario

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

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