What airlines fly to Chicago?

American Airlines, United Airlines and Spirit Airlines are the top three most popular airlines that fly to Chicago from Ontario according to our data. American Airlines is the first choice among our users, with 43% of people opting to fly with this airline when traveling to Chicago. Keep in mind that there are 9 different airlines that fly to Chicago on a routine basis, so you have a few additional options to choose from.

How many flights depart from Ontario to Chicago on average per day?

As of August 2025, 1 flights take off from Ontario and land in Chicago each day. The most common flight departure time for this route is 7:00AM, with 91% of daily flights taking off at noon.

Which layover airport offers the lowest fares from Ontario to Chicago?

Flights via Salt Lake City (SLC) offer the lowest average round-trip price of $256.

How many flights depart from Ontario to Chicago on average per week?

The number of flights available between Ontario and Chicago is 9 per week as of August 2025. The most frequent departure day is Tue, with 33% of weekly flights leaving on this day.

Which airport is the most popular layover for flights between Ontario and Chicago?

Denver (DEN) was the most common stop: 38% of momondo users choosing 1-stop flights on this route connected there.

Which layover airport has the shortest travel time from Ontario to Chicago?

Flights connecting via Phoenix (PHX) have the shortest average one-way travel time: 5h 32m.

What is the cheapest airline that flies from Ontario to Chicago?

United Airlines, Southwest, and American Airlines are the most popular carriers operating from Ontario to Chicago

Which layover airport has the shortest connection time from Ontario to Chicago?

Phoenix (PHX) has the shortest average layover time for this route: 0h 43m.

When did momondo last update prices for flights from Ontario Airport to Chicago?

Prices for flights from Ontario Airport to Chicago were last updated today.

How many operators does momondo search for flights from Ontario Airport to Chicago?

As of August 2025, there are 5 operators available to choose from for flights from Ontario Airport to Chicago.

How old do you have to be to fly from Ontario Airport to Chicago?

Although the minimum age for a child to fly alone is five, airlines that offer an unaccompanied minor (UMNR) service may have their own age limits, which could be impacted by factors such as flight length, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Ontario Airport to Chicago.

What documentation or ID do you need to fly to Chicago?

The travel and health documents required for your trip to Chicago can vary based on your itinerary and personal situation. As a rule, consider having multiple documents such as a national ID card or driver’s license, and a passport valid for six-months after you plan to arrive at Chicago. We always recommend checking with your airline or a trusted third party such as IATA to get advice.

$87 Cheap Flights from Ontario to Chicago (ONT-CHI) in 2025

Q: What is the typical price of a round-trip flight between Ontario and Chicago?

Prices are currently low for flights on this route. Typical prices usually range from $250 to $466. The lowest price recently found on this route was $173.

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Find the cheapest flights from Ontario to Chicago (ONT-CHI)

Round-trip

One-way

Last minute

Direct

Cheap round-trip flights

7:00 am - 1:03 pmONT-ORD

4h 03mnonstop

7:59 pm - 10:30 pmORD-ONT

4h 31mnonstop

$173United Airlines

Find Deal

Wed, Sep 17 - Wed, Sep 24

7:00 am - 1:03 pmONT-ORD

4h 03mnonstop

7:59 pm - 10:30 pmORD-ONT

4h 31mnonstop

$190United Airlines

Find Deal

Mon, Sep 1 - Wed, Sep 10

8:15 am - 7:15 pmONT-ORD

9h 00m1 stop

3:08 pm - 10:33 pmORD-ONT

9h 25m1 stop

$193American Airlines

Find Deal

Wed, Sep 17 - Wed, Sep 24

9:00 pm - 5:10 amONT-MDW

6h 10m1 stop

8:20 pm - 10:30 pmMDW-ONT

4h 10mnonstop

$200Southwest

Find Deal

Tue, Sep 9 - Thu, Sep 11

11:55 am - 5:45 pmONT-MDW

3h 50mnonstop

8:20 pm - 10:30 pmMDW-ONT

4h 10mnonstop

$207Southwest

Find Deal

Tue, Sep 9 - Thu, Sep 11

11:29 pm - 9:49 amONT-ORD

8h 20m1 stop

12:33 pm - 9:24 pmORD-ONT

10h 51m1 stop

$210American Airlines

Find Deal

Mon, Sep 1 - Wed, Sep 10

12:59 am - 12:32 amONT-ORD

21h 33m1 stop

7:00 am - 11:50 pmORD-ONT

18h 50m1 stop

$238Frontier

Find Deal

Fri, Aug 15 - Sat, Aug 23

12:04 pm - 12:01 amONT-ORD

9h 57m1 stop

8:25 am - 7:23 amORD-ONT

24h 58m1 stop

$240Frontier

Find Deal

Sat, Aug 30 - Sat, Sep 6

11:36 am - 10:14 pmONT-MDW

8h 38m1 stop

12:48 pm - 7:19 pmMDW-ONT

8h 31m1 stop

$257Delta

Find Deal

Tue, Oct 14 - Tue, Oct 21

11:55 am - 9:36 pmONT-MDW

7h 41m1 stop

1:43 pm - 11:42 pmMDW-ONT

11h 59m2 stops

$262Delta

Find Deal

Fri, Sep 26 - Tue, Sep 30

United Airlines flights from Ontario to Chicago

Our best United Airlines deals on Ontario to Chicago flight tickets

United Airlines

Sep 17

ONT7:00 amOntario

4h 03m

ORD1:03 pmChicago O'Hare Intl

Sep 24

ORD7:59 pmChicago O'Hare Intl

4h 31m

ONT10:30 pmOntario

$173

Find similar

United Airlines

Sep 1

ONT7:00 amOntario

4h 03m

ORD1:03 pmChicago O'Hare Intl

Sep 10

ORD7:59 pmChicago O'Hare Intl

4h 31m

ONT10:30 pmOntario

$190

Find similar

United Airlines

Sep 17

ONT7:00 amOntario

4h 03m

ORD1:03 pmChicago O'Hare Intl

Sep 24

ORD7:19 amChicago O'Hare Intl

6h 54m

1 stop

ONT12:13 pmOntario

$200

Find similar

American Airlines flights from Ontario to Chicago

Our best American Airlines deals on Ontario to Chicago flight tickets

American Airlines

Sep 17

ONT8:15 amOntario

9h 00m

1 stop

ORD7:15 pmChicago O'Hare Intl

Sep 24

ORD3:08 pmChicago O'Hare Intl

9h 25m

1 stop

ONT10:33 pmOntario

$193

Find similar

American Airlines

Sep 1

ONT11:29 pmOntario

8h 20m

1 stop

ORD9:49 amChicago O'Hare Intl

Sep 10

ORD12:33 pmChicago O'Hare Intl

10h 51m

1 stop

ONT9:24 pmOntario

$210

Find similar

American Airlines

Sep 7

ONT4:45 pmOntario

5h 42m

1 stop

ORD12:27 amChicago O'Hare Intl

Sep 9

ORD11:54 amChicago O'Hare Intl

8h 22m

2 stops

ONT6:16 pmOntario

$215

Find similar

Fly from

Fly to

Route

Depart

Return

Price

OntarioChicago

ONT - ORD

ONTORD

Ontario

Wed 9/17

7:00 am-1:03 pm

Nonstop4h 03m

Chicago O'Hare Intl

Wed 9/24

7:59 pm-10:30 pm

Nonstop4h 31m

$173

OntarioChicago

ONT - ORD

ONTORD

Ontario

Mon 9/1

7:00 am-1:03 pm

Nonstop4h 03m

Chicago O'Hare Intl

Wed 9/10

7:59 pm-10:30 pm

Nonstop4h 31m

$190

OntarioChicago

ONT - ORD

ONTORD

Ontario

Wed 9/17

8:15 am-7:15 pm

1 stop9h 00m

Chicago O'Hare Intl

Wed 9/24

3:08 pm-10:33 pm

1 stop9h 25m

$193

OntarioChicago

ONT - MDW

ONTMDW

Ontario

Tue 9/9

9:00 pm-5:10 am

1 stop6h 10m

Chicago Midway

Thu 9/11

8:20 pm-10:30 pm

Nonstop4h 10m

$200

OntarioChicago

ONT - MDW

ONTMDW

Ontario

Tue 9/9

11:55 am-5:45 pm

Nonstop3h 50m

Chicago Midway

Thu 9/11

8:20 pm-10:30 pm

Nonstop4h 10m

$207

OntarioChicago

ONT - ORD

ONTORD

Ontario

Mon 9/1

11:29 pm-9:49 am

1 stop8h 20m

Chicago O'Hare Intl

Wed 9/10

12:33 pm-9:24 pm

1 stop10h 51m

$210

OntarioChicago

ONT - ORD

ONTORD

Ontario

Fri 8/15

12:59 am-12:32 am

1 stop21h 33m

Chicago O'Hare Intl

Sat 8/23

7:00 am-11:50 pm

1 stop18h 50m

$238

OntarioChicago

ONT - ORD

ONTORD

Ontario

Sat 8/30

12:04 pm-12:01 am

1 stop9h 57m

Chicago O'Hare Intl

Sat 9/6

8:25 am-7:23 am

1 stop24h 58m

$240

OntarioChicago

ONT - MDW

ONTMDW

Ontario

Tue 10/14

11:36 am-10:14 pm

1 stop8h 38m

Chicago Midway

Tue 10/21

12:48 pm-7:19 pm

1 stop8h 31m

$257

OntarioChicago

ONT - MDW

ONTMDW

Ontario

Fri 9/26

11:55 am-9:36 pm

1 stop7h 41m

Chicago Midway

Tue 9/30

1:43 pm-11:42 pm

2 stops11h 59m

$262

Flights are sorted by cheapest round-trip flights first.

Showing 1-10 of 20 resultsSorted by cheapest first

How to get the cheapest flight ticket from Ontario to Chicago

Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip

Prices

Airlines

Layovers

Other information

What is the typical price of a round-trip flight between Ontario and Chicago?

What is the cheapest month to fly to Chicago?

The month of November is, on average, the cheapest month to fly to Chicago from Ontario, with most prices found around $227. If you’re not able to fly to Chicago in November, then October is your next best option. Flight prices from Ontario to Chicago during October average around $276.

What is the cheapest day to depart on your flight to Chicago?

The cheapest day to depart on your flight to Chicago is on a Wednesday when prices can be found for as low as $359. This is often the case because there is less demand to fly during this day of the week. When flying out on a Sunday, the most expensive travel day of the week, you can expect to see flight prices from Ontario to Chicago for around $463.

What is the cheapest time of day to depart on your flight to Chicago?

Our most recent data shows that the best time of day to fly to Chicago is in the afternoon. Flights from Ontario to Chicago during this time can be as low as $284. In contrast, the most expensive time of day to depart to Chicago is at noon when prices are around $444.

What is the cheapest Ontario to Chicago flight route?

Fly from Ontario to Chicago O'Hare Intl for the best Ontario - Chicago flight prices

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

You are more likely to see cheaper flights to Chicago from Ontario when booking weeks ahead of your departure date. In general, you can expect to find flights to Chicago for around $365 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Chicago from Ontario for as low as $258 on momondo.

What cabin class options are available on Ontario to Chicago flights?

There are 4 cabin classes available to choose from on Ontario to Chicago flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.

Can stopping save me money on Ontario to Chicago flights?

You could potentially save up to 28% on your flight if you consider stops on a Ontario to Chicago flight.

How have Ontario to Chicago flight prices changed over time?

As of August 2025, prices for Ontario to Chicago flights are approximately 22% cheaper when compared to flights at the same time last year.

When to book flights from Ontario to Chicago

Are you open to changing your travel dates? Check out the ideal times to fly from Ontario to Chicago according to our flight data. Find out which month and days have the cheapest flights.

Estimated round-trip price

Cheap Ontario to Chicago (ONT to CHI) flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from Ontario to Chicago

Best Price Found	$87
Fastest flight time	3h 45m
Direct flights	Every day
Airports in Chicago	2 airports

The best one-way flight to Chicago from Ontario in the past 72 hours is $87. The best round-trip flight deal from Ontario to Chicago found on momondo in the last 72 hours is $173.

The fastest flight from Ontario to Chicago takes 3h 45m

Direct flights go from Ontario to Chicago every day.

There are 2 airports near Chicago: Chicago O'Hare Intl (ORD), Chicago Midway (MDW)

Search flight deals

How far is Ontario to Chicago by plane?
The straight-line distance from Ontario to Chicago is 1710.7 mi. 3h 45m is a normal flight duration for this route.
When did momondo last update prices for flights from Ontario Airport to Chicago?
Prices for flights from Ontario Airport to Chicago were last updated today.
How many operators does momondo search for flights from Ontario Airport to Chicago?
As of August 2025, there are 5 operators available to choose from for flights from Ontario Airport to Chicago.
How old do you have to be to fly from Ontario Airport to Chicago?
Although the minimum age for a child to fly alone is five, airlines that offer an unaccompanied minor (UMNR) service may have their own age limits, which could be impacted by factors such as flight length, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Ontario Airport to Chicago.
What documentation or ID do you need to fly to Chicago?
The travel and health documents required for your trip to Chicago can vary based on your itinerary and personal situation. As a rule, consider having multiple documents such as a national ID card or driver’s license, and a passport valid for six-months after you plan to arrive at Chicago. We always recommend checking with your airline or a trusted third party such as IATA to get advice.
What is the most popular plane model from Ontario to Chicago?
Based on momondo bookings for flights between Ontario and Chicago, the leading plane model is Airbus A321neo, making up 15.16% of the total bookings. Other popular models include Boeing 737-800 with 14.55%, Boeing 737 MAX 8 with 11.48%, and Airbus A320neo with 9.94%.
What is the most popular airline from Ontario to Chicago?
Based on momondo bookings for flights between Ontario and Chicago, the leading airline is Southwest, making up 31% of the total bookings. Other popular airlines include Frontier with 26%, United Airlines with 23%, and American Airlines with 11%.

Best airlines flying from Ontario to Chicago

Compare and see reviews for airlines that fly from Ontario to Chicago with momondo

Airline	Rating	Free Cancellation	Price
Spirit Airlines	PriceFrom $99	Free Cancellation	Rating 6.3 8,052 reviews	Search Spirit Airlines flights
Frontier	PriceFrom $108	Free Cancellation	Rating 5.8 3,232 reviews	Search Frontier flights
United Airlines	PriceFrom $227	Free Cancellation	Rating 7.4 8,910 reviews	Search United Airlines flights
Southwest	PriceFrom $237	Free Cancellation	Rating 8.0 4,247 reviews	Search Southwest flights
Delta	PriceFrom $241	Free Cancellation	Rating 8.0 7,990 reviews	Search Delta flights
American Airlines	PriceFrom $246	Free Cancellation	Rating 7.2 10,000 reviews	Search American Airlines flights

Southwest Flights From Ontario to Chicago
Southwest flight deals from Ontario to Chicago start from $237 round-trip. Over the 2 Southwest flights for this route in a normal week, average airfare is usually $443 round-trip - but some users have found much cheaper deals with momondo.
United Airlines Flights From Ontario to Chicago
The best United Airlines deal for Ontario to Chicago flight tickets found on momondo in the last 72 hours was $227, round-trip. It should be noted that an average United Airlines flight deal for this route in this time was higher, at $377 round-trip. United Airlines operates 7 flights out of Ontario into Chicago in an average week, so prices vary by time and availability. 8,910 United Airlines reviews by users on momondo have scored the airline at 7.4/10.

Merrillville

New Buffalo

Hammond

Benton Harbor

Saint Joseph

Lansing

Portage

Schererville

Valparaiso

Crown Point

Munster

Chesterton

Monticello

Porter

Griffith

Saint John

Why use momondo?

Why should I use momondo to find a flight deal from Ontario to Chicago?

momondo collates all your flight options in one place and lets you filter them to find the perfect flight from Ontario to Chicago. momondo saves you time and could save you money on your trip.

Can I find flights from Ontario to Chicago with flexible booking policies on momondo?

Yes. All flights to Chicago from Ontario on momondo can be compared and filtered by various policies on offer, including flexible booking.

How can momondo help me find flights from Ontario to Chicago?

Once you have performed a search for Ontario to Chicago flights, momondo helps you find the right one by offering useful filters to narrow down your flight selection. Flights can be filtered by multiple factors such as airline, airport and price; but also by other criteria like aircraft type and payment method.

I’m not ready to book a flight from Ontario to Chicago right now. Can momondo alert me if prices change?

Of course. momondo tracks the price of Ontario to Chicago flights. All you need is a valid email address and we will do the rest; it is that quick and easy.

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Cheap flights from Ontario to Chicago from $87

This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from Ontario to Chicago departing on 9/9. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.

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Big names and deals

Filter for what you want

Filter for what you want

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Find the cheapest flights from Ontario to Chicago (ONT-CHI)

Cheap round-trip flights

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Cheap last minute flights

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United Airlines flights from Ontario to Chicago

Our best United Airlines deals on Ontario to Chicago flight tickets

American Airlines flights from Ontario to Chicago

Our best American Airlines deals on Ontario to Chicago flight tickets

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

See travel insights to Chicago from

How to get the cheapest flight ticket from Ontario to Chicago

Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip

What is the typical price of a round-trip flight between Ontario and Chicago?

What is the cheapest month to fly to Chicago?

The month of November is, on average, the cheapest month to fly to Chicago from Ontario, with most prices found around $227. If you’re not able to fly to Chicago in November, then October is your next best option. Flight prices from Ontario to Chicago during October average around $276.

What is the cheapest day to depart on your flight to Chicago?

What is the cheapest time of day to depart on your flight to Chicago?

Our most recent data shows that the best time of day to fly to Chicago is in the afternoon. Flights from Ontario to Chicago during this time can be as low as $284. In contrast, the most expensive time of day to depart to Chicago is at noon when prices are around $444.

What is the cheapest Ontario to Chicago flight route?

Fly from Ontario to Chicago O'Hare Intl for the best Ontario - Chicago flight prices

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

What cabin class options are available on Ontario to Chicago flights?

There are 4 cabin classes available to choose from on Ontario to Chicago flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.

Can stopping save me money on Ontario to Chicago flights?

You could potentially save up to 28% on your flight if you consider stops on a Ontario to Chicago flight.

How have Ontario to Chicago flight prices changed over time?

As of August 2025, prices for Ontario to Chicago flights are approximately 22% cheaper when compared to flights at the same time last year.

What is the cheapest airline that flies from Ontario to Chicago?

United Airlines, Southwest, and American Airlines are the most popular carriers operating from Ontario to Chicago

What airlines fly to Chicago?

Which airport is the most popular layover for flights between Ontario and Chicago?

Denver (DEN) was the most common stop: 38% of momondo users choosing 1-stop flights on this route connected there.

Which layover airport offers the lowest fares from Ontario to Chicago?

Flights via Salt Lake City (SLC) offer the lowest average round-trip price of $256.

Which layover airport has the shortest travel time from Ontario to Chicago?

Flights connecting via Phoenix (PHX) have the shortest average one-way travel time: 5h 32m.

Which layover airport has the shortest connection time from Ontario to Chicago?

Phoenix (PHX) has the shortest average layover time for this route: 0h 43m.

How many flights depart from Ontario to Chicago on average per day?

As of August 2025, 1 flights take off from Ontario and land in Chicago each day. The most common flight departure time for this route is 7:00AM, with 91% of daily flights taking off at noon.

How many flights depart from Ontario to Chicago on average per week?

The number of flights available between Ontario and Chicago is 9 per week as of August 2025. The most frequent departure day is Tue, with 33% of weekly flights leaving on this day.

When to book flights from Ontario to Chicago

Cheap Ontario to Chicago (ONT to CHI) flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from Ontario to Chicago

Best Price Found

Fastest flight time

Direct flights

Airports in Chicago

How far is Ontario to Chicago by plane?

When did momondo last update prices for flights from Ontario Airport to Chicago?

How many operators does momondo search for flights from Ontario Airport to Chicago?

How old do you have to be to fly from Ontario Airport to Chicago?

What documentation or ID do you need to fly to Chicago?

What is the most popular plane model from Ontario to Chicago?

What is the most popular airline from Ontario to Chicago?

Best airlines flying from Ontario to Chicago

Compare and see reviews for airlines that fly from Ontario to Chicago with momondo

Southwest Flights From Ontario to Chicago

United Airlines Flights From Ontario to Chicago

Traveling to a place near Chicago?

Why use momondo?

Why should I use momondo to find a flight deal from Ontario to Chicago?

Can I find flights from Ontario to Chicago with flexible booking policies on momondo?

How can momondo help me find flights from Ontario to Chicago?

I’m not ready to book a flight from Ontario to Chicago right now. Can momondo alert me if prices change?

An easier way to manage your Chicago trip

We make it super easy to schedule, organize and travel with friends or family. Trips is free — and available to use no matter where you book.