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$54+ 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 2/10. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — CHI
Nov 25 — Dec 21
Mon 11/25
Mon 12/2
1 adult, Economy
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The best prices from Ontario to Chicago are usually found in September or October, booked 76 days in advance, depart on a Wednesday or Saturday and return on a Tuesday

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 November 20, 2024.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Popular in

January

Cheapest in

September

Round-trip from

$128
(Frontier)

One-way from

$54
(Frontier)
Provider with most accurate pricing for Ontario-Chicago (CHI) flight deals.
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Provider most trusted by Cheapflights users for Ontario-Chicago (CHI) flights.
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High demand for flights, 15% potential price rise
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Best time to find cheap flights, 16% potential price drop
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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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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 November 20, 2024.

This Frontier deal was found by Cheapflights users on 11/18. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/58:56 amONT - MDW
1 stop10h 06mFrontier
Mon 12/97:15 amMDW - ONT
1 stop7h 45mFrontier
Deal found 11/18$128
This Frontier deal was found by Cheapflights users on 11/20. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/58:56 amONT - ORD
1 stop11h 11mFrontier
Fri 1/248:25 pmORD - ONT
1 stop12h 46mFrontier
Deal found 11/20$128
This eDestinos deal was found by Cheapflights users on 11/18. 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 eDestinos is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/1810:39 pmONT - ORD
1 stop28h 51mMultiple Airlines
Wed 12/256:00 amORD - ONT
2 stops28h 06mMultiple Airlines
Deal found 11/18$241
This Alaska Airlines deal was found by Cheapflights users on 11/20. 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.
Wed 12/111:53 pmONT - ORD
1 stop7h 54mAlaska Airlines
Thu 1/93:35 pmORD - ONT
1 stop8h 38mAlaska Airlines
Deal found 11/20$251
This United Airlines deal was found by Cheapflights users on 11/18. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 12/286:50 pmONT - ORD
1 stop9h 04mUnited Airlines
Thu 1/28:45 amORD - ONT
1 stop5h 55mUnited Airlines
Deal found 11/18$282
This Delta deal was found by Cheapflights users on 11/20. 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.
Sat 12/77:10 amONT - ORD
1 stop7h 33mDelta
Tue 12/103:40 pmORD - ONT
1 stop9h 22mDelta
Deal found 11/20$284
This Delta deal was found by Cheapflights users on 11/20. 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.
Sat 12/712:05 pmONT - MDW
1 stop8h 01mDelta
Tue 12/102:15 pmMDW - ONT
2 stops10h 47mDelta
Deal found 11/20$289
This American Airlines deal was found by Cheapflights users on 11/18. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 12/134:25 pmONT - ORD
1 stop6h 20mAmerican Airlines
Sat 1/186:00 amORD - ONT
1 stop7h 58mAmerican Airlines
Deal found 11/18$306
This Southwest deal was found by Cheapflights users on 11/18. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/182:50 pmONT - ORD
1 stop6h 15mSouthwest
Fri 12/206:15 amORD - ONT
2 stops8h 55mSouthwest
Deal found 11/18$402
This Southwest deal was found by Cheapflights users on 11/19. 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.
Fri 12/62:50 pmONT - MDW
1 stop5h 10mSouthwest
Tue 12/1010:00 amMDW - ONT
Nonstop4h 25mSouthwest
Deal found 11/19$495

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 2,629,791 searches. Data last updated November 20, 2024.

Fly from

Any airport

Fly to

Any airport

Route

Depart

Return

Price

OntarioChicago

ONT - MDW

ONTMDW

Ontario

Thu 12/5

8:56 am-9:02 pm

1 stop10h 06m

Chicago Midway

Mon 12/9

7:15 am-1:00 pm

1 stop7h 45m

$128

OntarioChicago

ONT - ORD

ONTORD

Ontario

Thu 12/5

8:56 am-10:07 pm

1 stop11h 11m

Chicago O'Hare Intl

Mon 12/9

7:25 am-1:00 pm

1 stop7h 35m

$128

OntarioChicago

ONT - ORD

ONTORD

Ontario

Wed 12/18

10:39 pm-5:30 am

1 stop28h 51m

Chicago O'Hare Intl

Wed 12/25

6:00 am-8:06 am

2 stops28h 06m

$241

OntarioChicago

ONT - ORD

ONTORD

Ontario

Wed 1/22

7:00 am-5:38 pm

1 stop8h 38m

Chicago O'Hare Intl

Tue 1/28

11:47 am-6:37 pm

1 stop8h 50m

$246

OntarioChicago

ONT - ORD

ONTORD

Ontario

Wed 12/11

1:53 pm-11:47 pm

1 stop7h 54m

Chicago O'Hare Intl

Thu 1/9

3:35 pm-10:13 pm

1 stop8h 38m

$251

OntarioChicago

ONT - ORD

ONTORD

Ontario

Tue 2/4

6:00 am-2:12 pm

1 stop6h 12m

Chicago O'Hare Intl

Tue 2/18

7:20 pm-11:53 pm

1 stop6h 33m

$256

OntarioChicago

ONT - MDW

ONTMDW

Ontario

Wed 1/22

6:00 am-5:47 pm

2 stops9h 47m

Chicago Midway

Tue 1/28

6:00 am-11:50 am

1 stop7h 50m

$261

OntarioChicago

ONT - ORD

ONTORD

Ontario

Sat 12/28

6:50 pm-5:54 am

1 stop9h 04m

Chicago O'Hare Intl

Thu 1/2

8:45 am-12:40 pm

1 stop5h 55m

$282

OntarioChicago

ONT - ORD

ONTORD

Ontario

Tue 1/7

12:25 pm-11:05 pm

2 stops8h 40m

Chicago O'Hare Intl

Sun 1/12

6:15 am-12:45 pm

2 stops8h 30m

$352

OntarioChicago

ONT - MDW

ONTMDW

Ontario

Fri 1/17

11:15 am-5:00 pm

Nonstop3h 45m

Chicago Midway

Mon 1/20

5:40 pm-8:15 pm

Nonstop4h 35m

$378

Flights are sorted by cheapest round-trip flights first.

Deals found on 11/20

Showing 1-10 of 22 results
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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 November.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*3 stars
eDreamsPrice Accuracy3 starsTrust Score*3 stars
AranGrantPrice Accuracy3 starsTrust Score*3 stars
FlightnetworkPrice Accuracy3 starsTrust Score*3 stars
CheapfaremartPrice Accuracy-Trust Score*1 star

*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 November 15, 2024.

The best time to book flights from Ontario to Chicago is 76 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 November 20, 2024.

Unlike at noon, when flights are generally more expensive, you can save up to 28% 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 November 18, 2024.

Travelers seeking maximum savings on their Ontario to Chicago flight should consider departing on Saturday afternoons 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 November 20, 2024.
To help decide which airline to fly from Ontario to Chicago, see what other customers have to say about American 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
5,014 reviews

Boarding

8.2

Comfort

8.1

Crew

8.7

Overall

8.1

Entertainment

7.7

Food

7.2

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
5,014 reviews
Southwest
8.1
Very good
5,014 reviews

Boarding

8.2

Comfort

8.1

Crew

8.7

Overall

8.1

Entertainment

7.7

Food

7.2

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
9,461 reviews
Southwest
8.1
Very good
5,014 reviews

Boarding

8.2

Comfort

8.1

Crew

8.7

Overall

8.1

Entertainment

7.7

Food

7.2

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
8,756 reviews
Southwest
8.1
Very good
5,014 reviews

Boarding

8.2

Comfort

8.1

Crew

8.7

Overall

8.1

Entertainment

7.7

Food

7.2

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
9,171 reviews
Southwest
8.1
Very good
5,014 reviews

Boarding

8.2

Comfort

8.1

Crew

8.7

Overall

8.1

Entertainment

7.7

Food

7.2

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
5,014 reviews

Boarding

8.2

Comfort

8.1

Crew

8.7

Overall

8.1

Entertainment

7.7

Food

7.2

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 1 outbound flight 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 $128. Other airlines that can offer you cheap pricing are American Airlines, from $246, and Alaska Airlines, from $251. These flights start at 58% 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 ($54), American Airlines ($109), and United Airlines ($119).

  • 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.

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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 2,629,791 searches. Data last updated November 20, 2024.
AirlineCheapestAverageFlexibilityOn-time
Spirit AirlinesCheapest$92Average$197FlexibilityNo cancel feeOn-time65%
FrontierCheapest$109Average$190FlexibilityNo cancel feeOn-time62%
DeltaCheapest$236Average$413FlexibilityNo cancel feeOn-timeN/A
American AirlinesCheapest$254Average$381FlexibilityNo cancel feeOn-time71%
United AirlinesCheapest$278Average$451FlexibilityNo cancel feeOn-time69%
SouthwestCheapest$336Average$480FlexibilityNo cancel feeOn-time63%
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