Chicago

$112+ Cheap flights from Ontario (ONT) to Chicago (CHI)

ONT — CHI
Dec 13 — Dec 201
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Find cheap flights from Ontario to Chicago with Cheapflights

1. Tell us where you want to go

Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”

2. Select your favorite providers

We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.

3. Compare prices and book

Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.
Cheapflights Tip: The best prices from Ontario to Chicago are usually found in January or September, booked 85 days in advance, depart on a Wednesday or Saturday and return on a Thursday

Cheap flight deals from Ontario to Chicago

Cheapest flights from Ontario to Chicago

Wed 12/25:00 pm -
1 stop5h 15m
Sat 12/510:25 am -
Nonstop4h 20m
Deal found 11/9$271
Wed 12/26:40 pm -
1 stop9h 48m
Sat 12/54:15 pm -
Nonstop4h 29m
Deal found 11/9$271
Sun 12/2010:33 pm -
1 stop29h 16m
Wed 1/61:00 pm -
2 stops21h 05m
Deal found 11/10$272
Wed 12/26:00 am -
1 stop8h 31m
Fri 12/48:49 pm -
1 stop12h 55m
Deal found 11/9$273
Tue 12/156:00 am -
1 stop16h 54m
Sun 12/207:35 am -
1 stop16h 03m
Deal found 11/9$274
Sun 11/158:03 pm -
1 stop11h 21m
Sat 12/127:25 am -
2 stops17h 58m
Deal found 11/8$275
Sat 11/146:30 am -
1 stop15h 51m
Sat 12/127:25 am -
2 stops17h 58m
Deal found 11/8$276
Tue 12/111:30 am -
1 stop11h 23m
Wed 12/29:13 am -
2 stops15h 07m
Deal found 11/9$277
Thu 12/38:00 am -
1 stop18h 59m
Tue 12/85:35 am -
2 stops18h 42m
Deal found 11/11$278
Thu 12/38:00 am -
1 stop18h 59m
Sat 12/56:21 am -
2 stops19h 02m
Deal found 11/11$279
Wed 12/1611:30 am -
1 stop11h 24m
Thu 12/247:00 am -
1 stop19h 13m
Deal found 11/12$280
Sat 12/511:30 am -
1 stop11h 24m
Wed 12/96:21 am -
1 stop7h 30m
Deal found 11/13$281

Find flight deals from Ontario to Chicago

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$271
(Southwest)

One-way from

$112
(Super.com)

Popular in

June

Cheapest in

January

Average price

$447

Good round-trip deal

$390 or less

Good one-way deal

$158 or less
Provider with most accurate pricing for Ontario-Chicago (CHI) flight deals.
Provider most trusted by Cheapflights users for Ontario-Chicago (CHI) flights.
From Ontario to Chicago (CHI)
One-way flight from Ontario to Chicago (CHI)
Highest demand for flights based on searches. 11% potential increase in price ($54 potential increase over avg. RT price).
Cheapest flight prices on average. 1% potential price decrease ($6 potential savings vs. average RT price).
Average for round-trip flights in November 2026
Price to beat on a round-trip flight from Ontario to Chicago (CHI).
Price to beat on a one-way flight from Ontario to Chicago (CHI).

Cheapflights Fare Finder

 
Use the filters below to find and compare flights from Ontario to Chicago that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

OntarioChicago

ONT Ontario - MDW Chicago Midway

ONTMDW

Ontario

Wed 2/3

6:30 am-12:25 pm

Nonstop3h 55m

Chicago Midway

Wed 12/31

12:00 am-10:00 pm

Nonstop0h 00m

$131

OntarioChicago

ONT Ontario - MDW Chicago Midway

ONTMDW

Ontario

Wed 1/6

1:07 pm-10:17 pm

1 stop7h 10m

Chicago Midway

Wed 12/31

12:00 am-10:00 pm

Nonstop0h 00m

$141

OntarioChicago

ONT Ontario - MDW Chicago Midway

ONTMDW

Ontario

Wed 12/9

7:05 am-4:16 pm

1 stop7h 11m

Chicago Midway

Wed 12/31

12:00 am-10:00 pm

Nonstop0h 00m

$141

OntarioChicago

ONT Ontario - MDW Chicago Midway

ONTMDW

Ontario

Thu 1/7

6:30 am-12:25 pm

Nonstop3h 55m

Chicago Midway

Wed 12/31

12:00 am-10:00 pm

Nonstop0h 00m

$146

OntarioChicago

ONT Ontario - MDW Chicago Midway

ONTMDW

Ontario

Tue 12/15

5:55 pm-9:37 am

2 stops13h 42m

Chicago Midway

Wed 12/31

12:00 am-10:00 pm

Nonstop0h 00m

$146

OntarioChicago

ONT Ontario - MDW Chicago Midway

ONTMDW

Ontario

Wed 12/16

7:05 am-4:16 pm

1 stop7h 11m

Chicago Midway

Wed 12/31

12:00 am-10:00 pm

Nonstop0h 00m

$146

OntarioChicago

ONT Ontario - MDW Chicago Midway

ONTMDW

Ontario

Wed 2/3

6:00 am-6:00 pm

2 stops10h 00m

Chicago Midway

Wed 12/31

12:00 am-10:00 pm

Nonstop0h 00m

$146

OntarioChicago

ONT Ontario - ORD Chicago O'Hare Intl

ONTORD

Ontario

Wed 2/3

7:00 am-9:36 pm

2 stops12h 36m

Chicago O'Hare Intl

Wed 12/31

12:00 am-10:00 pm

Nonstop0h 00m

$146

OntarioChicago

ONT Ontario - ORD Chicago O'Hare Intl

ONTORD

Ontario

Tue 12/8

1:11 pm-9:56 pm

1 stop6h 45m

Chicago O'Hare Intl

Wed 12/31

12:00 am-10:00 pm

Nonstop0h 00m

$146
Quickest round-trip

OntarioChicago

ONT Ontario - ORD Chicago O'Hare Intl

ONTORD

Ontario

Thu 12/24

11:52 pm-5:46 am

Nonstop3h 54m

Chicago O'Hare Intl

Wed 12/31

12:00 am-10:00 pm

Nonstop0h 00m

$156

Flights are sorted by cheapest round-trip flights first.

Deals found on 11/8

Showing 1-10 of 42 resultsSorted by cheapest first
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5

Compare providers for flights from Ontario to Chicago

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 Accuracy2 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

Cheapflights Insights

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

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

Currently, January is the cheapest month in which you can book a flight from Ontario to Chicago (average of $318). Flying from Ontario to Chicago in July is currently the most expensive (average of $481). 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?

When flying from Ontario to Chicago, the time of day you decide to fly out makes little to no difference towards the overall price you’ll pay on tickets.

How much does it cost to fly round-trip from Ontario to Chicago?

Airfare is below average for this route at the moment.
Ontario to Chicago flights typically cost between $374 and $555 in December.
The cheapest round-trip price found within the last 5 days was $271 on Southwest (Dec 2-Dec 5).

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

The best time to book flights from Ontario to Chicago is 82 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.

The best insider tips for Ontario to Chicago flights

Cheapflights partnered with top experts to bring you the best recommendations for your Ontario to Chicago trip
Our travel experts
Ramsey Qubein

Ramsey Qubein

Expert on MDW

An avid traveler and aviation expert who has visited 173 countries, all 50 states and seven continents, Ramsey Qubein flies nearly 400,000 miles a year. As a North Carolina-based freelance journalist for publications including Conde Nast Traveler, Forbes, USA Today and Bloomberg among others, he explores the latest trends in aviation, hospitality, cruises and business.

Bill Fink

Bill Fink

Expert on ONT

Bill is an award-winning travel writer with extensive credits covering airlines and the aviation industry for publications including AARP, AFAR, The Points Guy and Yahoo. Based in Portland, Oregon, Bill has traveled to more than 75 countries - and been late for his flight in most of them. He once achieved top-level frequent flier status for all of American, Delta and United Airlines during a single year.

Reviews of airlines servicing Chicago

See what other customers who have flown with Southwest,Delta, andUnited Airlines from Ontario to Chicago have to say. You can also see how each airline compares in terms of entertainment options, comfort, food, crew/service, and boarding process.

Overall

8.0

Entertainment

7.5

Boarding

8.1

Comfort

8.0

Food

7.0

Crew

8.6

Reviews

1 / 20
6.0
Good

Reza,Jun 2026

TPA - MDW

The seats were super cramped and couldn’t move without hitting other passengers

Overall

8.0

Entertainment

7.5

Boarding

8.1

Comfort

8.0

Food

7.0

Crew

8.6

Reviews

1 / 20
6.0
Good

Reza,Jun 2026

TPA - MDW

The seats were super cramped and couldn’t move without hitting other passengers

Overall

8.0

Entertainment

7.5

Boarding

8.1

Comfort

8.0

Food

7.0

Crew

8.6

Reviews

1 / 20
6.0
Good

Reza,Jun 2026

TPA - MDW

The seats were super cramped and couldn’t move without hitting other passengers

Overall

8.0

Entertainment

7.5

Boarding

8.1

Comfort

8.0

Food

7.0

Crew

8.6

Reviews

1 / 20
6.0
Good

Reza,Jun 2026

TPA - MDW

The seats were super cramped and couldn’t move without hitting other passengers

Overall

8.0

Entertainment

7.5

Boarding

8.1

Comfort

8.0

Food

7.0

Crew

8.6

Reviews

1 / 20
6.0
Good

Reza,Jun 2026

TPA - MDW

The seats were super cramped and couldn’t move without hitting other passengers

Overall

8.0

Entertainment

7.5

Boarding

8.1

Comfort

8.0

Food

7.0

Crew

8.6

Reviews

1 / 20
6.0
Good

Reza,Jun 2026

TPA - MDW

The seats were super cramped and couldn’t move without hitting other passengers

Related info for your journey

  • 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 5 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.

  • How long is the flight from Ontario to Chicago?

    Southwest, United Airlines, and Delta can get you from Ontario to Chicago in just under 3h 55m. Your travel time can differ by up to 6h 05m. The distance from Ontario to Chicago is about 1701 mi. When browsing for deals, the options you’ll see will be for both nonstop flights and flights with stops.

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

    Cheapflights users have booked flights from Ontario to Chicago round-trip from $118. Other airlines that can offer you cheap pricing are Frontier, from $160, and Southwest, from $253. These flights start at 71% 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 ($90), Southwest ($119), and United Airlines ($129).

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

  • What are the cheapest flights from Ontario to Chicago?

    On average you can expect to pay $916 for a flight from Ontario to Chicago. The cheapest flight overall is $119 while the most popular route, (Ontario - Chicago O'Hare Intl) is currently priced at $232.

  • 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, January is the cheapest month in which you can book a flight from Ontario to Chicago (average of $318). Flying from Ontario to Chicago in July is currently the most expensive (average of $481). 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

Traveling to a place near Chicago?

Book flights to Chicago if you plan to visit one of these locations
Benton Harbor
Merrillville
Lansing
Valparaiso
Hammond
Saint Joseph
Porter

Browse thousands of different options on Cheapflights for your next trip

Alternative routes for Ontario to Chicago

Top 5 airlines flying from Ontario to Chicago

AirlineCheapestAverageFlexibilityOn-time
DeltaCheapest$118Average$336FlexibilityNo cancel feeOn-timeN/A
FrontierCheapest$160Average$259FlexibilityNo cancel feeOn-time62%
SouthwestCheapest$253Average$500FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$275Average$448FlexibilityNo cancel feeOn-time69%
American AirlinesCheapest$276Average$397FlexibilityNo cancel feeOn-time71%

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