$105 Find Cheap Flights from Ontario to Illinois

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Low seasonJanuary
Cheapest flight$105
Best time to beat the crowds but there is an average 17% increase in price.
Most popular time to fly and prices are also 1% lower on average.
Flight from Montreal 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 Canada
YYZ
-
ORD
Oct 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 Airlines
YYZ
-
ORD
Mar 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 (116 flights per week), Air Canada (114 flights per week), and Air New Zealand (75 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 91% 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 $248.

  • What is the cheapest day to fly to Illinois?

    Based on KAYAK data, the cheapest day to fly to Illinois is Friday where round-trip tickets can be as cheap as $455. On the other hand, the most expensive day to fly is Monday, where round-trip prices are $727 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 $368 on average. Morning departures are around 30% 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 $668.

  • 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 $133 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 $133.

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

    The cheapest month for flights from Ontario to Illinois is September, when tickets cost $342 (return) on average. On the other hand, the most expensive months are January and March, when the average cost of round-trip tickets is $806 and $754 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 52% compared to booking last minute. For the absolute cheapest price, our data suggests you should book 24 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 566 direct flights each week.

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

    There are around 93 direct flights from within Ontario to Illinois every day. Most flights (49%) depart in the morning.

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

    Each week there are around 651 direct flights from within Ontario to Illinois. The most common day for departures is Sunday, with 19% of flights taking off on this day.

  • How long is the flight to Illinois?

    An average nonstop flight from Ontario to Illinois takes 8h 45m, 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 651 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 (92% of total searches to Illinois). The next most popular destinations are Peoria (3%) and Bloomington (2%). Searches for flights to Champaign (1%), to Moline (1%) and to Decatur (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.
8.0
Porter AirlinesOverall score based on 406 reviews
7.0Entertainment
7.9Comfort
7.6Food
8.2Boarding
8.6Crew
Airline reviews

It was okay. Had a thing with the front desk, she had me repack my suitcases to have them be under the weight restrictions, but then the other one was overweight, she argued with me about it when there were tons of people in line. Wasn’t great.

6.0 GoodJen, Jan 2026
YTZ - BOS
Read more Porter Airlines reviews

It was okay. Had a thing with the front desk, she had me repack my suitcases to have them be under the weight restrictions, but then the other one was overweight, she argued with me about it when there were tons of people in line. Wasn’t great.

Due to a known technical error that Porter has not fixed in over a year, I was unable to check in the children on my reservation online and had to do it at the airport. Upon check in, there were no seats together, which was an issue as we had young children. The gate agent did manage to seat us together by moving other passengers, which was appreciated, but the other passengers were never informed, leading to confusion and delay upon boarding. The flight was over an hour late; no explanation or apology was ever issued. The bags on Porter take a long time to arrive--over half an hour at Hamilton on my inbound flight, and not much better on my return to Edmonton.

On my e-boarding pass it shows free wifi, yet the plane I was on didn’t have wifi. Please remove false advertising from your website and boarding passes

3.5 hr delay for a 1 hr work flight. No information as to why the delay until 20 mins before boarding.

Organization and the adjusted times but the snacks could be of a bigger portion

I like it, but the food isn't good. They need to offer more simple things. This bowls that have so many things your don't know what your are eating. The milenials like it, no the rest. And last but not least, they allowed somebody have a huge dog, vey agressive and fidgety in the flight. That's horrible. No animals should be allowed inside the airplane, what about allergies, etc

Smaller plane. Food and bar service for free is amazing. Drinks were in glass not plastic cups.

Poor landing as we overshot the runway and had to re land the plane. Lost both of my luggage not found as of yet. Had to pay extra money for my luggage in USD, now great my luggage is gone. Will not fly with Porter again.

This flight to St. Johns was really good. Boarding was a breeze. We left spot on time. Seats were actually pretty good. Recliner further than I expected. Three more flights to go we will see if this is the status quo for Porter.👍

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

I did not like I have been charged for my carry on

Onward flight was okay. return from Lisbon was poor as we missed our flight due to a long line at the passport control. Air Transat made no effort to accommodate us even though we were at the passport control 40 minutes prior to the departure.

Very good. A lot better experience then I expected for an economy flight.

It was very good but no tv but the experience was great

Thank you for making my first experience very enjoyable. You made it all very pleasant

Great flight great seats will absolutely fly with you again

Porter airlines was good. I didn't have the best experience when booking through airfare assist however, as I got no final confirmation from them that the flight was booked until I called them. Even then, the confirmation code they gave me was incorrect and couldn't be used for check in. On a positive note airfare assist was actually picked up the phone relatively quickly when calling

The flight crew were very good, polite, and professional. Unfortunately, the rest of the experience left much to be desired. The food was extremely bland—almost tasteless. We chose the non vegetarian .The lasagna was just plain pasta with a tiny garnish and no seasoning. It felt like eating starch only, The bigger issue was with luggage and space. We boarded with three tickets, and while the seats in front of us were nearly empty, all the overhead compartments had already been filled by passengers boarding to the back. This left us and many others with no overhead storage for our carry-ons. Our bags couldn’t fit well under the seats either, which meant we lost the little legroom we had. The result was a horrible, cramped experience—sore knees, no space to stretch, and no way to rest or sleep comfortably. According to the crew this was a rather normal thing. It is obviously normal that people board with handbag and carry on but they should be only allowed to use their overhead compartment and under their seat not the way it is managed that all the spaces in the front of the plane being occupied by the people sitting way back in the plane.

Nice complete meal included and great services. Plus the plane was very clean.

Everything was horrible. On the day of my departure, I was denied check-in and boarding because my reservation only showed one of my last names, while my passport contains both. This minor discrepancy could have been easily corrected, but I was informed that no adjustment could be made. As a result, I lost not only my outbound flight but also my return flight and had to purchase a new ticket at a significantly higher cost.

Perfect flight. Smooth flight. Arrived 20 minutes early at destination. Excellent service.

The flights were on time which was great give. It was holiday travel season and there’d been some weather issues. The only complaint and this is every time with United is the terrible seat design. The head rest is not built for comfort and having my neck bent forward for a cross country trip reminded me while I try not to take United flights as a rule.

Everything was absolutely wonderful from check in to baggage claim. Staff was very professional and sweet. Will definitely recommend United to family and friends.

The staff was nice, however boarding taking 2 hours. That’s insane. Overall very bad experience, a lot of turbulence and when landed in Chicago was horrible. I don’t think I’ll flight with UA again.

An international flight on an apron is pretty unusual in my 40 years of traveling. Departure delay. Luggage despite over an hour connection did not make it to the flight. Actually still in Germany. My luggage was not moved until I reached my final destination despite knowing it to be left in Germany upon my arrival in Chicago. The service left me a little off, both going and returning from Europe. Light on in the cabin even during a night flight and lots of traffic no matter what. Maybe passengers want more service? As a frequent traveler i just want to be able to sleep, the food will be better at the destination anyway. So since the cabin crew woke me up I asked for a cocktail, I did not get the best response although sitting in row 20 premium economy. I usually fly premium economy or business and my 2 flight to Europe in 2025 with United both had luggage delays and other minor issues. American flights to Australia, Canada and Europe went smoothly and Premium plus feels very much like business light. Is United Club becoming a waste and Silver/Gold levels another waste??

They did the one thing that really matters - got to Chicago early.

The flight was on time. I generally don’t drink or eat on short flights and the seats were good and the flight attendants were friendly. That’s all I expect

It was nice to have gotten up upgraded to first class with a meal on a three hour flight

Very bad! They kept delaying my flight and wouldn’t do anything about it

Quick and seamless boarding. No entertainment but fast Starlink wifi for this short trip and the staff was really friendly.

So excited very proud first of all I wanna thank kayak all updates very professional and fast alart And amazing cabin crew so nice to me they deserve big salute

The boarding process needs to be fixed. The zone don't work, especially when there is hardly anyone in zones 3, 4,and 5, leaving the majority of the passengers backed up in the aisle, especially because passengers seated near the front are blocking passengers who are seated in the rear of the plane. It would also help if the size of carry on bags was more strictly enforced.

Awful. They won’t help me with anything. I booked on American but they abdicated to Iberia. The ticket was overpriced. Everything negative

I enjoyed the extra leg room compared to other airlines. The first stewards made my daughter’s birthday special by giving her an extra snack. Then the last one coming home from Chicago to Appleton made our night really enjoyable Thanks for making our trip enjoyable

It was good..clean, comfy seat. Friendly warm welcoming crew. Was able to check my cabin luggage at the gate which I was able to pickup in a decent time from baggage claim. The app gave all updates from delays to baggage claim info. Overall smooth flight.

It was a typical flight. We had a delay which seems to be the normality now. And we had no in flight service due to conditions.

After we landed we sat on the tarmac for 1.5 hours waiting to get to our gate. Ridiculous.

Flight, food and crew were all good, friendly and very satisfactory.

Terrible. Flight delayed for more than 8 hours with only a $12 meal voucher provided for the inconvenience. The airplane did not have breaks on arrival yet they still made us go through the motions and board on time knowing we could not take off then sit for 40+ minutes before having to get of the time. A complete waste of my time. I cannot believe they can stay business with these shenanigans. I’ll avoid this company like the plague moving forward as the lack of accountability is disgraceful.

This was the best 2 flights I have had with American out of SGF. Great crew both flights.

My seat was covered in vomit and I will be reaching out to Air Canada

It's kindof ridiculous that your system is even asking me about this since my flight was canceled and I wasn't rescheduled.

3 hr delay at the gate while they were doing maintenance. Next time, do not board passengers while maintenance is being performed

Digital check in is very poor with air canada compaired to other airlines

Baggage delayed we had to catch our cruise without any clothes 😒

Air Canada Rouge is great. Toronto Airport is the usual nightmare

Good but need to be better with the flight times.

The staff was great and made the long trip easy peasy!

The free Wi-fi for Aeroplan members was a great touch. The time passed quickly. I found the seats seemed a little closer together than I remember. Not Air Canada's fault, but we were about 20 minutes late landing because the airport was too busy. We had to circle around for a while. The boarding and disembarking went very smoothly.

Extremely turbulent landing. Crew was friendly and plane comfortable. Airport and US pre clearance was understaffed

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.