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$74+ Cheap flights from Ontario (ONT) to Chicago (CHI)

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 2/21. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — CHI
Dec 23 — Dec 301
Mon 12/23
Mon 12/30
1 adult, Economy
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The best prices from Ontario to Chicago are usually found in November or September, booked 88 days in advance, depart on a Wednesday or Tuesday and return on a Friday

Cheap flight deals from Ontario to Chicago

Discover tips and strategies to find the most affordable flight options for your journey from Ontario (ONT) to Chicago (CHI). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated December 18, 2024.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$145
(Trip.com)

One-way from

$74
(Cheapflightsfares)

Popular in

January

Cheapest in

November

Average price

$360
Provider with most accurate pricing for Ontario-Chicago (CHI) flight deals.
Search Deals
Provider most trusted by Cheapflights users for Ontario-Chicago (CHI) flights.
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From Ontario to Chicago (CHI)
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One-way flight from Ontario to Chicago (CHI)
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High demand for flights, 13% potential price rise
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Best time to find cheap flights, 2% potential price drop
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Average for round-trip flights in December 2024
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Find flight deals from Ontario to Chicago

Cheapest flights from Ontario to Chicago
Explore the most affordable flight options available from Ontario to Chicago. Find the lowest fares from popular airlines and budget airlines, with prices last updated on December 18, 2024.

This Booking.com deal was found by Cheapflights users on 12/17. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/3012:59 amONT - ORD
1 stop10h 21mFrontier
Mon 1/66:00 amORD - ONT
1 stop19h 59mFrontier
Deal found 12/17$158
This CheapOair deal was found by Cheapflights users on 12/17. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/3112:59 amONT - MDW
1 stop18h 33mFrontier
Sun 1/58:41 pmMDW - ONT
1 stop12h 28mFrontier
Deal found 12/17$168
This American Airlines deal was found by Cheapflights users on 12/17. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/3111:59 pmONT - ORD
1 stop9h 04mAmerican Airlines
Tue 1/75:00 amORD - ONT
1 stop6h 56mAmerican Airlines
Deal found 12/17$417
This Orbitz deal was found by Cheapflights users on 12/17. 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 Orbitz is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/3012:59 amONT - ORD
1 stop10h 21mMultiple Airlines
Tue 1/77:45 amORD - ONT
2 stops11h 19mMultiple Airlines
Deal found 12/17$426
This Delta deal was found by Cheapflights users on 12/17. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/315:30 amONT - MDW
2 stops9h 41mDelta
Mon 1/65:07 pmMDW - ONT
1 stop7h 45mDelta
Deal found 12/17$447
This Delta deal was found by Cheapflights users on 12/18. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/255:30 amONT - ORD
1 stop6h 21mDelta
Sat 1/47:05 pmORD - ONT
1 stop7h 23mDelta
Deal found 12/18$464
This United Airlines deal was found by Cheapflights users on 12/17. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 12/221:57 pmONT - ORD
1 stop9h 14mUnited Airlines
Sat 1/182:39 pmORD - ONT
1 stop8h 12mUnited Airlines
Deal found 12/17$472
This Alaska Airlines deal was found by Cheapflights users on 12/17. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/268:32 pmONT - ORD
1 stop6h 58mAlaska Airlines
Wed 1/86:55 pmORD - ONT
1 stop29h 18mAlaska Airlines
Deal found 12/17$490
This KAYAK deal was found by Cheapflights users on 12/16. 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 KAYAK is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/185:35 amONT - ORD
1 stop6h 50mSouthwest
Thu 12/196:15 amORD - ONT
1 stop13h 05mSouthwest
Deal found 12/16$492
This Southwest deal was found by Cheapflights users on 12/17. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/312:50 pmONT - MDW
1 stop6h 35mSouthwest
Mon 1/610:00 amMDW - ONT
Nonstop4h 25mSouthwest
Deal found 12/17$498

Find flights from Ontario to Chicago within your budget

Customize your flight search to find flights from Ontario to Chicago 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 December 18, 2024.

Fly from

Any airport

Fly to

Any airport

Route

Depart

Return

Price

OntarioChicago

ONT - MDW

ONTMDW

Ontario

Wed 1/8

12:34 pm-11:48 am

1 stop21h 14m

Chicago Midway

Wed 1/15

8:15 am-11:44 pm

1 stop17h 29m

$145

OntarioChicago

ONT - ORD

ONTORD

Ontario

Fri 1/10

10:40 am-12:35 am

1 stop11h 55m

Chicago O'Hare Intl

Mon 1/13

6:20 am-8:25 pm

1 stop16h 05m

$145

OntarioChicago

ONT - ORD

ONTORD

Ontario

Wed 1/29

3:04 pm-11:59 pm

1 stop6h 55m

Chicago O'Hare Intl

Tue 2/4

11:47 am-6:37 pm

1 stop8h 50m

$168

OntarioChicago

ONT - ORD

ONTORD

Ontario

Thu 1/16

7:56 am-5:25 pm

1 stop7h 29m

Chicago O'Hare Intl

Wed 1/29

2:07 pm-8:13 pm

1 stop8h 06m

$182

OntarioChicago

ONT - ORD

ONTORD

Ontario

Fri 2/7

4:06 pm-2:03 pm

1 stop19h 57m

Chicago O'Hare Intl

Mon 2/10

3:35 pm-10:34 am

1 stop20h 59m

$210

OntarioChicago

ONT - MDW

ONTMDW

Ontario

Thu 1/30

7:05 am-4:21 pm

1 stop7h 16m

Chicago Midway

Sat 2/1

3:41 pm-10:52 pm

1 stop9h 11m

$256

OntarioChicago

ONT - ORD

ONTORD

Ontario

Fri 1/17

1:21 pm-9:22 pm

1 stop6h 01m

Chicago O'Hare Intl

Thu 1/23

2:25 pm-10:32 pm

1 stop10h 07m

$256

OntarioChicago

ONT - ORD

ONTORD

Ontario

Tue 1/28

10:20 am-10:35 pm

2 stops10h 15m

Chicago O'Hare Intl

Thu 1/30

5:45 am-1:25 pm

2 stops9h 40m

$292

OntarioChicago

ONT - ORD

ONTORD

Ontario

Fri 1/17

1:45 pm-11:59 pm

1 stop8h 14m

Chicago O'Hare Intl

Wed 1/22

7:10 am-12:41 pm

1 stop7h 31m

$336

OntarioChicago

ONT - MDW

ONTMDW

Ontario

Thu 2/20

11:15 am-5:00 pm

Nonstop3h 45m

Chicago Midway

Sun 2/23

9:00 am-11:30 am

Nonstop4h 30m

$340

Flights are sorted by cheapest round-trip flights first.

Deals found on 12/18

Showing 1-10 of 20 results
1
2

Compare providers for flights from Ontario to Chicago

Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Ontario to Chicago in December.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*3 stars
eDreamsPrice Accuracy3 starsTrust Score*3 stars
FlightnetworkPrice Accuracy2 starsTrust Score*3 stars
AranGrantPrice Accuracy3 starsTrust Score*2 stars
CheapfaremartPrice Accuracy-Trust Score*3 stars

*The Trust Score is based on feedback from users after their booking experience. It measures overall satisfaction, helping us identify issues like hidden fees, problems during the ticketing process, and the quality of customer service. This score is our best indicator of the provider's quality and reliability.

  • Most accurate provider: When it comes to deals on Ontario-Chicago flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Ontario-Chicago flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Ontario-Chicago flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Ontario-Chicago flights, Cheapflights users trust FlightHub the most. FlightHub has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for Ontario-Chicago flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

Best time to book a flight from Ontario to Chicago

Have a flexible travel schedule? Discover the best time to fly to Chicago 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.

Travel insights for flights from Ontario to Chicago

Get recent, data-driven insights about flights from Ontario to Chicago including ideal travel times, pricing trends, and more.

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

Use this chart to determine the optimal time to book a round-trip flight from Ontario to Chicago. Price data was last updated on December 13, 2024.

The best time to book flights from Ontario to Chicago is 88 days before your desired departure date. The cost of your flight will likely increase significantly if you book two weeks in advance of your flight.

What is the cheapest month to book a flight from Ontario to Chicago?

Currently, September is the cheapest month in which you can book a flight from Ontario to Chicago (average of $232). Flying from Ontario to Chicago in June is currently the most expensive (average of $308). 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 ONT to CHI?

Find hourly flight availability from Ontario to Chicago. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated December 18, 2024.

Unlike in the morning, when flights are generally more expensive, you can save up to 30% on flights from Ontario to Chicago by exploring options for tickets in the evening.

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

Use this chart to determine the cheapest time to fly round-trip from Ontario to Chicago. Price data was last updated on December 16, 2024.

Travelers seeking maximum savings on their Ontario to Chicago flight should consider departing on Saturday evenings when fares are most often at their lowest. Tuesday afternoons flights should be avoided if possible as fares are typically the most expensive at this time.

Rainfall in Chicago by month

Plan your trip to Chicago by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in Chicago ranges from 1.7 - 4.9 inches per month. August is typically the wettest month, when rainfall can reach 4.9 in. January is typically the driest time to visit Chicago when rainfall is around 1.7 in.

Temperature in Chicago by month

Plan your trip to Chicago by taking into account the average temperature totals by month.

If weather is an important factor for your trip to Chicago, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 73.4 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 23.0 F).

Reviews of airlines servicing Chicago

Get insights into the airlines that provide service to Chicago. 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 Chicago. Reviews last updated December 18, 2024.
To help decide which airline to fly from Ontario to Chicago, see what other customers have to say about Alaska Airlines, Frontier and United Airlines. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.1
Very good
4,848 reviews

Entertainment

7.7

Boarding

8.2

Crew

8.7

Comfort

8.1

Food

7.2

Overall

8.1

Reviews

1 / 10

My original flight was delayed so they found this flight for me so I could arrive at a reasonable time

Southwest
8.1
Very good
4,848 reviews
Southwest
8.1
Very good
4,848 reviews

Entertainment

7.7

Boarding

8.2

Crew

8.7

Comfort

8.1

Food

7.2

Overall

8.1

Reviews

1 / 10

My original flight was delayed so they found this flight for me so I could arrive at a reasonable time

Alaska Airlines
8.0
Very good
9,554 reviews
Southwest
8.1
Very good
4,848 reviews

Entertainment

7.7

Boarding

8.2

Crew

8.7

Comfort

8.1

Food

7.2

Overall

8.1

Reviews

1 / 10

My original flight was delayed so they found this flight for me so I could arrive at a reasonable time

Delta
8.0
Very good
8,604 reviews
Southwest
8.1
Very good
4,848 reviews

Entertainment

7.7

Boarding

8.2

Crew

8.7

Comfort

8.1

Food

7.2

Overall

8.1

Reviews

1 / 10

My original flight was delayed so they found this flight for me so I could arrive at a reasonable time

United Airlines
7.4
Good
9,055 reviews
Southwest
8.1
Very good
4,848 reviews

Entertainment

7.7

Boarding

8.2

Crew

8.7

Comfort

8.1

Food

7.2

Overall

8.1

Reviews

1 / 10

My original flight was delayed so they found this flight for me so I could arrive at a reasonable time

American Airlines
7.2
Good
10,000 reviews
Southwest
8.1
Very good
4,848 reviews

Entertainment

7.7

Boarding

8.2

Crew

8.7

Comfort

8.1

Food

7.2

Overall

8.1

Reviews

1 / 10

My original flight was delayed so they found this flight for me so I could arrive at a reasonable time

Related info for your journey

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

  • What airport do you fly from for flights from Ontario to Chicago?

    Ontario (ONT) is the airport you will fly out of if you book a flight from Ontario to Chicago. You should not have trouble finding flights to Chicago from Ontario; the airport handles an average of 0 outbound flights to Chicago per day. You should also have plenty of airline options to choose from since 6 airlines have flights from the Ontario airport to Chicago. It is only a 3.1 mi journey to Ontario (ONT) from Ontario’s city center.

  • What are the cheapest airlines flying from Ontario to Chicago round-trip?

    Cheapflights users have booked flights from Ontario to Chicago round-trip from $145. Other airlines that can offer you cheap pricing are American Airlines, from $168, and Alaska Airlines, from $210. These flights start at 52% lower than the current average price 3 months from now.

  • What are the cheapest airlines to fly from Ontario to Chicago one-way?

    The cheapest airlines for a one-way flight from Ontario to Chicago are Frontier ($74), American Airlines ($84), and Alaska Airlines ($99).

  • What are the most popular routes from Ontario to Chicago?

    Most travelers choose Ontario - Chicago O'Hare Intl, Ontario - Chicago Midway or Ontario - Chicago Greater Rockford when deciding on the best route from Ontario to Chicago.

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

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

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

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

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

    Yes. Cheapflights offers flight deals from Ontario to Chicago 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 Ontario to Chicago?

    Currently, September is the cheapest month in which you can book a flight from Ontario to Chicago (average of $232). Flying from Ontario to Chicago in June is currently the most expensive (average of $308). 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.

See more FAQs

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Alternative routes for Ontario to Chicago

See prices for flight routes from nearby airports that may be better suited for you.
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Top 6 airlines flying from Ontario to Chicago

Discover the top 6 airlines that operate flights from Ontario to Chicago. 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 December 18, 2024.
AirlineCheapestAverageFlexibilityOn-time
Spirit AirlinesCheapest$92Average$195FlexibilityNo cancel feeOn-time65%
FrontierCheapest$109Average$192FlexibilityNo cancel feeOn-time62%
DeltaCheapest$236Average$420FlexibilityNo cancel feeOn-timeN/A
American AirlinesCheapest$254Average$382FlexibilityNo cancel feeOn-time71%
United AirlinesCheapest$273Average$459FlexibilityNo cancel feeOn-time69%
SouthwestCheapest$358Average$505FlexibilityNo cancel feeOn-time63%
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