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Illinois

$128+ Cheap flights from Ontario to Illinois

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 10/20. Fares are subject to change and may not be available on all flights or dates of travel.
YYZ — ORD
Oct 14 — Oct 211
Tue 10/14
Tue 10/21
1 adult, Economy
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Cheap flight deals from Ontario to Illinois

Keep the following information in mind while searching for Ontario to Illinois flight deals. Data was last updated September 14, 2025.

Round-trip from

$196
(Kiwi.com)

One-way from

$128
(Kiwi.com)

Popular in

December

Cheapest in

July

Average price

$254

Good round-trip deal

$188 or less

Good one-way deal

$153 or less
From Ontario to Illinois
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One-way flight from Ontario to Illinois
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Highest demand for flights based on searches. 8% potential increase in price ($22 potential increase over avg. RT price).
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Cheapest flight prices on average. 1% potential price decrease ($4 potential savings vs. average RT price).
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Average for round-trip flights in September 2025
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Price to beat on a round-trip flight from Ontario to Illinois.
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Price to beat on a one-way flight from Ontario to Illinois.
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Find flight deals from Ontario to Illinois

Cheapest flights from Ontario to Illinois
Explore the most affordable flight options available from Ontario to Illinois. Find the lowest fares from popular airlines and budget airlines, with prices last updated on September 14, 2025.

This Kiwi.com deal was found by Cheapflights users on 9/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/204:00 pmYYZ - ORD
1 stop8h 44mMultiple Airlines
Thu 10/2312:53 pmORD - YYZ
1 stop7h 14mMultiple Airlines
Deal found 9/14$196
This Kiwi.com deal was found by Cheapflights users on 9/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 10/194:00 pmYYZ - ORD
1 stop24h 49mMultiple Airlines
Thu 10/237:43 pmORD - YYZ
1 stop17h 22mMultiple Airlines
Deal found 9/14$203
This Kiwi.com deal was found by Cheapflights users on 9/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/204:00 pmYYZ - ORD
1 stop8h 44mMultiple Airlines
Thu 10/307:06 pmORD - YYZ
1 stop25h 01mMultiple Airlines
Deal found 9/14$204
This Kiwi.com deal was found by Cheapflights users on 9/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/34:00 pmYYZ - ORD
1 stop7h 39mMultiple Airlines
Thu 11/66:06 pmORD - YYZ
1 stop26h 01mMultiple Airlines
Deal found 9/14$206
This Kiwi.com deal was found by Cheapflights users on 9/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/34:00 pmYYZ - ORD
1 stop7h 39mMultiple Airlines
Thu 11/136:06 pmORD - YYZ
1 stop26h 01mMultiple Airlines
Deal found 9/13$207
This Kiwi.com deal was found by Cheapflights users on 9/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 11/94:00 pmYYZ - ORD
1 stop19h 42mMultiple Airlines
Thu 11/136:06 pmORD - YYZ
1 stop26h 01mMultiple Airlines
Deal found 9/13$208
This Kiwi.com deal was found by Cheapflights users on 9/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/134:00 pmYYZ - ORD
1 stop8h 44mMultiple Airlines
Fri 10/247:20 pmORD - YYZ
1 stop24h 47mMultiple Airlines
Deal found 9/13$212
This Kiwi.com deal was found by Cheapflights users on 9/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/204:00 pmYYZ - ORD
1 stop8h 44mMultiple Airlines
Fri 10/315:25 amORD - YYZ
1 stop13h 35mMultiple Airlines
Deal found 9/13$216
This Kiwi.com deal was found by Cheapflights users on 9/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/204:00 pmYYZ - ORD
1 stop8h 44mMultiple Airlines
Fri 11/75:59 pmORD - YYZ
1 stop19h 41mMultiple Airlines
Deal found 9/14$217
This Vliegwinkel deal was found by Cheapflights users on 9/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Vliegwinkel is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/31:10 pmYUL - MDW
1 stop4h 14mPorter Airlines
Sun 10/55:20 pmMDW - YUL
1 stop3h 55mPorter Airlines
Deal found 9/12$234
This FlightHub deal was found by Cheapflights users on 9/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/1710:45 amYUL - MDW
1 stop6h 39mPorter Airlines
Mon 10/209:35 amMDW - YUL
1 stop5h 25mPorter Airlines
Deal found 9/12$235
This Bravofly deal was found by Cheapflights users on 9/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Bravofly is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/186:20 amYYZ - MDW
1 stop5h 10mWestJet
Sat 10/2510:35 amMDW - YYZ
1 stop5h 15mWestJet
Deal found 9/14$236

Cheapflights Fare Finder

 
Customize your flight search to find flights from Ontario to Illinois that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated September 14, 2025.
Use the filters below to find and compare flights from Ontario to Illinois that are best for you.

Fly from

Ontario

Fly to

Illinois

Route

Depart

Return

Price

MontrealChicago

YUL - MDW

YULMDW

Montreal Pierre Elliott Trudeau Intl

Fri 10/17

1:10 pm-4:24 pm

1 stop4h 14m

Chicago Midway

Mon 10/20

9:35 am-4:00 pm

1 stop5h 25m

$235

TorontoChicago

YTZ - MDW

YTZMDW

Toronto Island

Sat 10/18

7:50 am-8:39 am

Nonstop1h 49m

Chicago Midway

Sat 10/25

9:35 am-12:17 pm

Nonstop1h 42m

$240

TorontoChicago

YTZ - MDW

YTZMDW

Toronto Island

Wed 10/15

7:50 am-8:39 am

Nonstop1h 49m

Chicago Midway

Wed 10/22

9:35 am-12:17 pm

Nonstop1h 42m

$240

MontrealChicago

YUL - MDW

YULMDW

Montreal Pierre Elliott Trudeau Intl

Wed 11/19

6:45 am-10:05 am

1 stop4h 20m

Chicago Midway

Mon 11/24

11:00 am-4:30 pm

1 stop4h 30m

$241

MontrealChicago

YUL - MDW

YULMDW

Montreal Pierre Elliott Trudeau Intl

Wed 11/19

6:45 am-10:05 am

1 stop4h 20m

Chicago Midway

Wed 11/26

4:15 pm-10:45 pm

1 stop5h 30m

$241

MontrealChicago

YUL - MDW

YULMDW

Montreal Pierre Elliott Trudeau Intl

Fri 11/21

11:25 am-3:20 pm

1 stop4h 55m

Chicago Midway

Mon 11/24

11:00 am-5:45 pm

1 stop5h 45m

$241

MontrealChicago

YUL - MDW

YULMDW

Montreal Pierre Elliott Trudeau Intl

Wed 11/19

6:45 am-10:05 am

1 stop4h 20m

Chicago Midway

Tue 11/25

11:00 am-4:30 pm

1 stop4h 30m

$241

TorontoChicago

YTZ - ORD

YTZORD

Toronto Island

Sat 10/18

3:25 pm-8:17 pm

1 stop5h 52m

Chicago O'Hare Intl

Sat 10/25

8:40 am-2:45 pm

1 stop5h 05m

$251

MontrealChicago

YUL - ORD

YULORD

Montreal Pierre Elliott Trudeau Intl

Fri 10/24

6:15 am-8:01 am

Nonstop2h 46m

Chicago O'Hare Intl

Sun 11/2

7:15 am-10:20 am

Nonstop2h 05m

$260

MontrealChicago

YUL - ORD

YULORD

Montreal Pierre Elliott Trudeau Intl

Thu 11/20

6:00 am-8:00 am

Nonstop3h 00m

Chicago O'Hare Intl

Sat 11/29

10:38 am-2:00 pm

Nonstop2h 22m

$260

Flights are sorted by cheapest round-trip flights first.

Deals found on 9/12

Showing 1-10 of 60 results
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Best time to book a flight from Ontario to Illinois

Have a flexible travel schedule? Discover the best time to fly to Illinois from Ontario with our price prediction graph.
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Cheapflights Insights

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

What is the cheapest month to book a flight from Region of Ontario to Illinois?

Currently, August is the cheapest month in which you can book a flight from Region of Ontario to Illinois (average of $245). Flying from Region of Ontario to Illinois in March is currently the most expensive (average of $321). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

What is the cheapest time of day to fly from ON to IL?

Find hourly flight availability from Ontario to Illinois. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated September 14, 2025.

Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Region of Ontario to Illinois as you normally would.

Weekly flight availability from Region of Ontario to Illinois

Explore weekly flight availability from Ontario to Illinois. Discover flights operating on different days of the week, giving you the flexibility to choose a travel day that best fits your plans. Compare info to find the most convenient option for your journey. Data last updated September 14, 2025.

The most flights from CAON to USIL are scheduled on a Monday (62 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (52 on average).

How much does it cost to fly round-trip from Region of Ontario to Illinois?

Reviews of airlines servicing Illinois

Get insights into the airlines that provide service to Illinois. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Illinois. Reviews last updated September 14, 2025.
See what other customers who have flown with Porter Airlines, Air Transat, and United Airlines from Ontario to Illinois have to say. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
Porter Airlines
7.9
Good
363 reviews

Overall

7.9

Entertainment

7.0

Boarding

8.1

Food

7.6

Crew

8.6

Comfort

7.9

Reviews

1 / 20
2.0
Mediocre

Anonymous,Sep 2025

YYZ - OPO

Very disappointing, booked with Porter airlines and changed to Air Transit last minute. Old plane, cramped seating, even the aisle was the narrowest I’ve ever seen. Very uncomfortable flight. Full meal at 130 am and only a small piece of banana bread in the morning… should be opposite.
Porter Airlines
7.9
Good
363 reviews
Porter Airlines
7.9
Good
363 reviews

Overall

7.9

Entertainment

7.0

Boarding

8.1

Food

7.6

Crew

8.6

Comfort

7.9

Reviews

1 / 20
2.0
Mediocre

Anonymous,Sep 2025

YYZ - OPO

Very disappointing, booked with Porter airlines and changed to Air Transit last minute. Old plane, cramped seating, even the aisle was the narrowest I’ve ever seen. Very uncomfortable flight. Full meal at 130 am and only a small piece of banana bread in the morning… should be opposite.
Air Transat
7.7
Good
438 reviews
Porter Airlines
7.9
Good
363 reviews

Overall

7.9

Entertainment

7.0

Boarding

8.1

Food

7.6

Crew

8.6

Comfort

7.9

Reviews

1 / 20
2.0
Mediocre

Anonymous,Sep 2025

YYZ - OPO

Very disappointing, booked with Porter airlines and changed to Air Transit last minute. Old plane, cramped seating, even the aisle was the narrowest I’ve ever seen. Very uncomfortable flight. Full meal at 130 am and only a small piece of banana bread in the morning… should be opposite.
United Airlines
7.4
Good
8,931 reviews
Porter Airlines
7.9
Good
363 reviews

Overall

7.9

Entertainment

7.0

Boarding

8.1

Food

7.6

Crew

8.6

Comfort

7.9

Reviews

1 / 20
2.0
Mediocre

Anonymous,Sep 2025

YYZ - OPO

Very disappointing, booked with Porter airlines and changed to Air Transit last minute. Old plane, cramped seating, even the aisle was the narrowest I’ve ever seen. Very uncomfortable flight. Full meal at 130 am and only a small piece of banana bread in the morning… should be opposite.
American Airlines
7.2
Good
10,000 reviews
Porter Airlines
7.9
Good
363 reviews

Overall

7.9

Entertainment

7.0

Boarding

8.1

Food

7.6

Crew

8.6

Comfort

7.9

Reviews

1 / 20
2.0
Mediocre

Anonymous,Sep 2025

YYZ - OPO

Very disappointing, booked with Porter airlines and changed to Air Transit last minute. Old plane, cramped seating, even the aisle was the narrowest I’ve ever seen. Very uncomfortable flight. Full meal at 130 am and only a small piece of banana bread in the morning… should be opposite.
Air Canada
7.1
Good
10,000 reviews
Porter Airlines
7.9
Good
363 reviews

Overall

7.9

Entertainment

7.0

Boarding

8.1

Food

7.6

Crew

8.6

Comfort

7.9

Reviews

1 / 20
2.0
Mediocre

Anonymous,Sep 2025

YYZ - OPO

Very disappointing, booked with Porter airlines and changed to Air Transit last minute. Old plane, cramped seating, even the aisle was the narrowest I’ve ever seen. Very uncomfortable flight. Full meal at 130 am and only a small piece of banana bread in the morning… should be opposite.

Related info for your journey

Find useful and relevant information for your journey from Ontario to Illinois. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • How long is the flight from Region of Ontario to Illinois?

    Porter Airlines, Air Canada, and United Airlines can get you from Region of Ontario to Illinois in just under 3h. Your travel time can differ by up to 2h 52m. Airlines will cover a distance of 745 mi. Both multi-stop and nonstop flights can be found to your destination and back.

  • What are the cheapest airlines to fly from Region of Ontario to Illinois one-way?

    $136 is the cheapest one-way deal found within the past few days, from Porter Airlines. You may also be able to find cheap deals on Air Canada and United Airlines, with prices starting from $155 and $157, respectively.

  • Can I find deals for flights from Ontario to Illinois that include hotel bookings?

    Yes. In addition to deals on Ontario to Illinois flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Ontario to Illinois?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Ontario to Illinois.

  • Can I find deals for business class flights from Ontario to Illinois?

    Yes. Cheapflights offers flight deals from Ontario to Illinois by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

  • What is the cheapest month to book a flight from Region of Ontario to Illinois?

    Currently, August is the cheapest month in which you can book a flight from Region of Ontario to Illinois (average of $245). Flying from Region of Ontario to Illinois in March is currently the most expensive (average of $321). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

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Alternative routes for Ontario to Illinois

See prices for flight routes from nearby airports that may be better suited for you.
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Top 4 airlines flying from Ontario to Illinois

Discover the top 4 airlines that operate flights from Ontario to Illinois. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated September 14, 2025.
AirlineCheapestAverageFlexibilityOn-time
Air CanadaCheapest$146Average$411FlexibilityNo cancel feeOn-time67%
Porter AirlinesCheapest$158Average$258FlexibilityNo cancel feeOn-time52%
United AirlinesCheapest$165Average$402FlexibilityNo cancel feeOn-time69%
American AirlinesCheapest$196Average$341FlexibilityNo cancel feeOn-time71%

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