CHI - ONT

$42 Find Cheap Flights from Chicago to Ontario

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from Chicago to Ontario departing on 6/12. 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.
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KAYAK searches hundreds of travel sites at once for deals on flights to Ontario

 
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Chicago to Ontario, 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 Chicago to Ontario, as well as popular online travel agencies
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Cheap Flight Deals from Chicago to Ontario (CHI-ONT)

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from Chicago to Ontario that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.

Recent round-trip flight deals from Chicago to Ontario

KAYAK's recommended round-trip deals from the most popular airlines that fly from Chicago to Ontario.
Discover the best prices for you by selecting your travel dates on KAYAK.
Frontier Logo
6:00 am - 9:15 amORD-ONT
29h 15m1 stop
Frontier Logo
12:59 am - 11:52 pmONT-ORD
20h 53m1 stop
$201Frontier
Find Deal
週六, 5月 24 - 週五, 5月 30
Frontier Logo
2:44 pm - 9:15 amMDW-ONT
20h 31m1 stop
Frontier Logo
12:59 am - 8:53 pmONT-MDW
17h 54m1 stop
$201Frontier
Find Deal
週六, 5月 24 - 週五, 5月 30
United Airlines Logo
7:55 pm - 10:26 pmORD-ONT
4h 31mnonstop
United Airlines Logo
7:00 am - 1:03 pmONT-ORD
4h 03mnonstop
$227United Airlines
Find Deal
週一, 6月 2 - 週三, 6月 4
Southwest Logo
8:30 pm - 10:45 pmMDW-ONT
4h 15mnonstop
Southwest Logo
2:55 pm - 10:50 pmONT-MDW
5h 55m1 stop
$237Southwest
Find Deal
週日, 6月 1 - 週一, 6月 2
United Airlines Logo
7:55 pm - 10:26 pmORD-ONT
4h 31mnonstop
United Airlines Logo
6:41 pm - 6:19 amONT-ORD
9h 38m1 stop
$237United Airlines
Find Deal
週二, 6月 3 - 週一, 6月 9
American Airlines Logo
12:48 pm - 9:33 pmORD-ONT
10h 45m1 stop
American Airlines Logo
12:59 am - 10:10 amONT-ORD
7h 11m1 stop
$247American Airlines
Find Deal
週二, 6月 10 - 週五, 6月 13
American Airlines Logo
6:30 pm - 11:59 pmORD-ONT
7h 29m1 stop
American Airlines Logo
12:55 pm - 10:31 pmONT-ORD
7h 36m1 stop
$249American Airlines
Find Deal
週六, 6月 14 - 週六, 6月 21
Delta Logo
7:20 pm - 11:46 pmORD-ONT
6h 26m1 stop
Delta Logo
10:05 pm - 8:39 amONT-ORD
8h 34m1 stop
$257Delta
Find Deal
週五, 6月 13 - 週五, 6月 20
Delta Logo
7:20 pm - 11:46 pmORD-ONT
6h 26m1 stop
Delta Logo
5:50 pm - 8:27 amONT-ORD
12h 37m2 stops
$262Delta
Find Deal
週五, 6月 13 - 週五, 6月 20
Southwest Logo
8:30 pm - 10:45 pmMDW-ONT
4h 15mnonstop
Southwest Logo
5:10 am - 11:00 amONT-MDW
3h 50mnonstop
$272Southwest
Find Deal
週日, 6月 1 - 週一, 6月 2
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KAYAK's insights & trends for Chicago to Ontario flights

Get data-powered insights and trends into flights from Chicago to Ontario to help you find the cheapest flights, the best time to fly and much more.

What is the cheapest Chicago to Ontario flight route?

The cheapest price for flight routes found by users searching on KAYAK in the last 2 weeks for round-trip flights from Chicago to Ontario.

Our data shows that the cheapest route for a return flight from Chicago to Ontario cost $227 and was between Chicago O'Hare Intl Airport (ORD) and Ontario (ONT). On average, the best prices are found if you fly this route. The average price for a return flight for this route is $227.

What’s the cheapest day of the week to fly from Chicago to Ontario?

The average price of all round-trip flights from Chicago to Ontario clicked on KAYAK for each day over the last 12 months.

For Chicago to Ontario, Thursday is the cheapest day to fly on average and Thursday is the most expensive. Flying from Ontario back to Chicago, the best deals are generally found on Monday, with Sunday being the most expensive.

What is the cheapest month to fly from Chicago to Ontario?

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from Chicago to Ontario, removes the top 0.1% to account for outliers, and then takes the median of all values for each month.

The cheapest month for flights from Chicago to Ontario is November, where tickets cost $148 (return) on average. On the other hand, the most expensive months are December and April, where the average cost of round-trip tickets is $422 and $356 respectively.

Can I save money by flying with a layover from Chicago to Ontario?

The average round-trip price for all non-stop flights, flights with one layover, and flights with two layovers for the route found by users searching on KAYAK in the last 2 weeks.

Yes, flying with a layover may cost you more time, but you can also save money on the route, with a 1 stop layover the cheapest option at $490 on average.

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

To calculate weekly average prices, KAYAK takes all prices for each week before departure over the last year for round-trip flights from Chicago to Ontario, removes the top 0.1% to account for outliers, and then takes the average of all the values for each week.

To get a below average price on the flight from Chicago to Ontario, you should book around 2 weeks before departure. For the absolute cheapest price, our data suggests you should book 8 weeks before departure.

Good to know

Low seasonJanuary
High seasonJune
Cheapest flight$42
Best time to beat the crowds but there is an average 1% increase in price.
Most popular time to fly with an average 14% increase in price.
Flight from Chicago O'Hare Airport to Ontario

When to book flights from Chicago to Ontario

Are your dates flexible? Find out the best times to travel from Chicago to Ontario based on our flight data from the last year. Discover the cheapest month and even day to fly.
Estimated round-trip price
KAYAK looks at all historical flight data for each date to provide a predicted price for one-way trips or round-trips with a duration up to 40 days. While we try to provide actual minimum prices for each date, some prices are predictions and actual prices may differ.

FAQs for booking flights from Chicago to Ontario

  • What are the most common layover airports for flights from Chicago to Ontario?

    Some of the most typical layover airports for various airlines traveling from Chicago to Ontario are Phoenix Sky Harbor International Airport (PHX), Dallas/Fort Worth International Airport (DFW), and Denver International Airport (DEN). If you are flying with American Airlines, your layover airports will be PHX or DFW. DEN, on the other hand, serves as a layover airport for Frontier aircraft.

  • Which airline(s) should I book if I am to travel with my pet(s) from Chicago to Ontario?

    Although most airlines flying from Chicago to Ontario allow pets, booking with Alaska Airlines has a number of advantages for pet owners. When compared to other airlines on this route, Alaska features some of the lowest pet fees. Furthermore, pets are permitted to travel in-cabin as long as their combined weight with that of the carrier does not exceed 20 lbs.

  • Can I get an eco-friendly flight from Chicago to Ontario?

    Yes. Several airlines operating from Chicago to Ontario - including Delta, American Airlines, and Spirit Airlines - provide environmentally friendly flights between Chicago and Ontario. Among them, American Airlines leads the list as one of the most environmentally friendly airlines because of its carbon reduction projects, which aim to equip all of its planes with fuel-efficient engines.

  • Which airline(s) among those flying from Chicago to Ontario have an option to upgrade from economy to first class?

    Delta Airlines, American Airlines, and Spirit Airlines are among the airlines where you can upgrade to first class by adding a nominal fee to your ticket. By taking advantage of this opportunity, you can fly first class at a lower rate than if you booked first class directly.

  • What is the cheapest flight from Chicago to Ontario?

    In the last 3 days, the lowest price for a flight from Chicago to Ontario was $42 for a one-way ticket and $201 for a round-trip.

  • Do I need a passport to fly between Chicago and Ontario?

    Even though you are not required to have a passport, keep in mind that an official ID is needed to board the airplane.

  • Which airports will I be using when flying from Chicago to Ontario?

    On your way to Ontario, you’ll fly out from one of these Chicago airports: Chicago Midway or Chicago O'Hare Intl. You’ll be landing at Ontario.

  • Which airlines offer Wi-Fi service onboard planes from Chicago to Ontario?

    American Airlines, and Alaska Airlines offer inflight Wi-Fi service on the Chicago to Ontario flight route.

  • Which aircraft models fly most regularly from Chicago to Ontario?

    The Boeing 737 MAX 8 is the aircraft model that flies most regularly on the Chicago to Ontario flight route.

  • Which airline alliances offer flights from Chicago to Ontario?

    Star Alliance is the only airline alliance operating flights between Chicago and Ontario.

  • On which days can I fly direct from Chicago to Ontario?

    There are nonstop flights from Chicago to Ontario on a daily basis.

  • Which is the best airline for flights from Chicago to Ontario, Southwest or Delta?

    The two airlines most popular with KAYAK users for flights from Chicago to Ontario are Southwest and Delta. With an average price for the route of $432 and an overall rating of 8.0, Southwest is the most popular choice. Delta is also a great choice for the route, with an average price of $402 and an overall rating of 8.0.

  • How does KAYAK find such low prices on flights from Chicago to Ontario?

    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 Chicago to Ontario.

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

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Ontario from Chicago 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 Chicago to Ontario?

    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 Ontario with an airline and back to Chicago with another airline.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Chicago to Ontario?

    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 Ontario from Chicago up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

KAYAK’s top tips for finding a cheap flight from Chicago to Ontario

  • Looking for a cheap flight? 25% of our users found flights on this route for $113 or less one-way and $458 or less round-trip.
  • Chicago O'Hare International Airport (ORD) is the primary departure airport for flights from Chicago to Ontario. However, just a few flights leave from Chicago Midway International Airport (MDW). You have a better chance of finding a cheaper flight fare if you choose a less popular route with MDW as the departing airport. Ontario International Airport (ONT) is the only airport serving all flights from Chicago to Ontario.
  • When traveling from Downtown Chicago to ORD to catch a trip to Ontario, CTA Blue Line buses are the most cost-effective and dependable mode of transportation. However, if you are in a hurry, consider taking cabs - which are the quickest mode of transportation.
  • Booking with American Airlines or United Airlines, both of which use ORD as their hub, gives you the assurance of getting a flight that fits your schedule. This is due to the fact that both airlines operate the most daily flights from Chicago ORD to Ontario.
  • Consider flying Delta or American Airlines from Chicago to Ontario with your child(ren). Because of the big seats and extra legroom in all American Airlines cabins, you and your children will travel in luxury. Furthermore, both Delta and American Airlines give priority boarding to parents traveling with their children.
  • When you book a trip from Chicago to Ontario, you will have the option of connecting to a variety of different cities covered by ONT. Upland, Montclair, and Chino - just a few of the cities with easy access from Ontario International Airport.

Prefer to fly direct from Chicago to Ontario?

Find which airlines fly direct from Chicago to Ontario Airport, which days they fly and book direct flights.

Direct departures

Chicago to Ontario

Monday

Southwest, United Airlines

Southwest, United Airlines

Tuesday

Southwest, United Airlines

Southwest, United Airlines

Wednesday

Southwest, United Airlines

Southwest, United Airlines

Thursday

Southwest, United Airlines

Southwest, United Airlines

Friday

Southwest, United Airlines

Southwest, United Airlines

Saturday

Southwest, United Airlines

Southwest, United Airlines

Sunday

Southwest, United Airlines

Southwest, United Airlines

See more direct flights

Direct returns

Ontario to Chicago

Monday

Southwest, United Airlines

Southwest, United Airlines

Tuesday

Southwest, United Airlines

Southwest, United Airlines

Wednesday

Southwest, United Airlines

Southwest, United Airlines

Thursday

Southwest, United Airlines

Southwest, United Airlines

Friday

Southwest, United Airlines

Southwest, United Airlines

Saturday

Southwest, United Airlines

Southwest, United Airlines

Sunday

Southwest, United Airlines

Southwest, United Airlines

See more direct flights
See more direct flights

Top 5 airlines serving from Chicago to Ontario

 
See real verified KAYAK customer reviews for airlines flying from Chicago to Ontario. 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 Chicago to Ontario? 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 4294 reviews
7.1Food
8.0Comfort
7.6Entertainment
8.2Boarding
8.6Crew
Airline reviews

It was a perfect flight in all aspects! Both legs!

10.0 ExcellentAnonymous, Apr 2025LGB - SMF
Read more Southwest reviews

It was a perfect flight in all aspects! Both legs!

Boarding process, crew were good. But the seats were so uncomfortable that was all I could focus on. I literally had to sit forward so that all 3 of us could fit in row. I will try to avoid Southwest in the future for any flights over 60 minutes.

Great flight, 47 passengers on a 180 seat plane. Stewardess was pleasant and cheerful.

Great experience flying Southwest. The crew was really kind and helpful, and very friendly with our toddler.

My flight to Chicago left and landed early. My return flight left two minutes late and arrived 2 minutes late. My seat selections were ideal! There were no snacks going to Chicago and no snacks on the return trip. There are no charging outlets on board.

Plane late from DC to Austin 30 minutes. Crew made up much of the time enroute to San Diego.

Fine, but how to board on SW versus othrr airlines, is just lame. Goood staff though and all was solid otherwise.

One of the crew performed a hilarious skit to accompany the standard instructions. Passengers enjoyed it so much they applauded at the end!

Excellent experience. WiFi worked on this leg of My trip

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.

This had nothing to do with Delta… The flights were on time and flawless. The service was excellent. We purchased seats in (aisle/middle) comfort plus since this was a cross country flight. Unfortunately, the woman seated at the window was 300+ pounds and, as might be expected, covered up about a third of the middle seat also. there was absolutely nothing that Delta could have done about that… I just don’t know what the answer should be. If you purchase a seat, you should should be able to use the entire seat and not just the portion that someone else is not sitting/oozing in. Disappointing…there should be something that could be done….I'm just not sure what solution could be.

Seats are much much more comfortable than United, which is what I usually fly

If I pay extra for "comfort+" I expect leg room where I can stretch my legs. I was seated with an attendant's seat blocking my feet. Knee space was fine but my feet had less room than the non-"comfort+" seats. Also, don't go cheap on food when you have flights of 3+ hours. It's insulting.

Only one side of the heafphone jack work. Crew was friendly and helpful.

Great. Flight departed early and arrived early. Deplaning and baggage claim ww were quick.

They separated our seats and moved us to the back of the plane. Hundreds of dollars and thousands of miles used and this was my platinum member experience.

AC barely worked on a 50 minute flight. It was very warm the whole flight. Flight was very bumpy and hard landing.

Got on the plane and then needed to deboard the plane because they didn’t have any pilots?

The flight was canceled two hours before departure, it took over five hours to rebook us on another flight.

Rough day of travel all the way around. Wrong info given to us multiple times and mistakes in their booking making our trip 10 hours longer than planned. I’m bummed because I fly Delta all the time and love them. Mistakes happen. Just bummed that this was a rare trip our whole family was traveling together.

A bit rush for transit. Food and entertainment are not available

Smooth boarding process. Early departure, smooth flight, early arrival. The entertainment package has very good recent movie options. The flight crew were friendly and professional.

My flight was scheduled for about 6:05 departure. There were 11 gate changes from 4-7pm and the flight was 3 hours delayed due to operational issues. The plane taxied around the airport for about half an hour before stopping to be de-iced. It would have been nice if we were alerted of the plan to de-ice prior to the 30 minute drive around the airport. The flight attendant was friendly, which was the only redeeming thing about this flight. As a former flight attendant for United, I was extremely disappointed.

Delays took 2hours and thirty minutes making me miss my connecting flight and make me sit in the Chicago airport for 9 hours

Had a short delay once we boarded the aircraft in Chicago, but it was fixed in no time flat then we were on our way. The pilot was able to make up the time lost and we landed 5 minute later then schedualed . Great service

Our seats were all the way in back of the plane,

The seats on this flight were almost roomy enough to be the basic amount needed for human existence. I think my favorite part of this flight was it landed at an A gate, which was the most palatial part of Sea-Tac I've ever seen - a massive improvement from the S gates.

The seats on this flight were almost roomy enough to be the basic amount needed for human existence.

The flight attendants in First Class were mediocre at best. They did not take our tray away until we were about to land and only did so when I press the call button. The United person at the United Club was asked to get us our boarding pass since we missed the flight due in Chicago. She argued that we did not have seats on the flight given to us in Moline. Furthermore, she was adamant that we did not have a First Class ticket. After I spent much time with her trying to show we were correct, she reluctantly agreed. She was probably the most incompetent ticketing person I have ever met and I have traveled 3 million miles on United plus many additional miles with other carriers. United has definitely deteriorated in more than on way.

Short flight - no food understandable. Flight was delayed for over an hour. Overall, it was good.

I have long legs, my foot was out in the aisle and when a flight attendant came walking by and I didn't notice, instead of saying "excuse me" or anything like that, she kicked my foot. Extremely rude

Excellent! The gate agents were kind enough to rebook me on an earlier flight saving me from a 6 hour layover. Even my luggage made it despite the fact that the connection was technically too narrow. The flight itself was very comfortable, roomy, and clean. Plenty of space for my carryon items with plugs to charge my phone. After a long international flight of 14 hours, this was an excellent way to end my travels!

Great experience. Flight boarded easily. Departed early. Smooth flight. Great arrival in DC--almost no taxing! Almost direct to gate from runway. Crew was terrific. Same cookies and beverages in main cabin. I did not use the entertainment system on this flight.

Most of the delay was due to weather which is not what was at issue here. One delay was due to a missing flashlight and in the end the flashlight was actually found on the plane. The entertainment system is very limited. Live TV options offer only a few channels that are not very appealing. Boarding and deplaning are always difficult. It just takes too much time to get on and off the plane. On the plus side, I missed my connecting flight, but was easily able to book a later flight from the app while enroute.

You were more on time than United. I'm so over united delays.

The meals were mediocre and the alcohol selection was poor. I enjoyed the selection of movies and other entertainment.

I chatted with the captain before the flight, and similarly during the welcome announcement, he warned of a turbulent flight that may impact the in-flight service. However, once at altitude, he announced that the weather changed and he immediately turned off the seatbelt sign. But it appeared the cabin crew had already decided to take off this flight. They remained seated and then just chatted in the galley. The flight was fully catered, but only first class received service.

My flight attendant was attentive! The elderly person next to me was flatulent and the flight attendant could see that I was in distress and brought me some face masks

My boarding pass wouldn't pull up in the app very easily and had to really dig through my email. That caused a delay in TSA..

I had a TERRIBLE experience with the AA crew. I believe it was disability-related. It’s unlikely I will fly AA again.

The reps working at the airport counter were dumber than a second coat of paint.

My costume jewelry was stolen out of my bag. Got to airport and my bag weighed 45 pounds- 5 pounds over cost me $100 Long lines in tier one. No entertainment No WiFi no free drinks or snacks

Not very good. Paid in excess of $400 for assigned seating for my family and that was not provided. I want that money back.

The seats were hard molded plastic covered in plastic vinyl. And the scam to charge people extra to sit together. Don’t they know we can just ask someone to trade seats. And watching the staff separate young children from parents… super classy. We had to guilt them into offering up our seats. This companies policies suck. Don’t give them your money.

The seats were awful, hard plastic covered in sheet vinyl. The airline tries to scam you into paying extra to get seat together when the flight wasn’t full. They were going to separate a family with young children but my wife who had a row to herself gave up her seat so the young mom could be with her young boys. I’m never giving this airline my money again.

It was a short flight so no food or entertainment….

Everything went as planned. Crew was great. Seats were still not that comfortable.

No frills for sure. No gate announcements about flight delay, not even water to drink on the flight.

The plane was clean, the crew was friendly and helpful. It’s a low cost airline so there was no food, drinks or in flight entertainment but we didn’t expect any of these things. In the room for improvement department, they should install USB ports in seats to charge mobile devices.

I was surprised that all baggage, including carry on, were charged. Each additional bag went up in cost. Really disappointed in the additional costs.

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

Information on your arrival and departure airports

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