Currently, February is the cheapest month in which you can book a flight from Ontario to Illinois (average of $244). Flying from Ontario to Illinois in June is currently the most expensive (average of $342). 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.

How recently were the Ontario to Illinois flight deals updated?

The Ontario to Illinois flight deals you see on this page were last updated on 5/13.

What are the most popular airlines that fly from Ontario to Illinois?

Consider American Airlines, Delta or Frontier when booking your flight. These represent the most popular airlines when flying from Ontario to Illinois.

What are the most popular routes from Ontario to Illinois?

The most popular flight routes from Ontario to Illinois are Ontario - Chicago O'Hare Intl, Ontario - Chicago Midway and Ontario - Lambert-St Louis.

Can I find flights from Ontario to Illinois for under $200 on Cheapflights?

Yes, there are multiple flights from Ontario to Illinois for under $200. The cheapest flight booked recently is on Frontier for just $125, but on average you can expect to pay $140.

Are there last-minute flights available from Ontario to Illinois for under $200?

There are currently 20+ open flights from Ontario to Illinois within the next 7 days for less than $200.

What airport do you fly from for flights from Ontario to Illinois?

Ontario (ONT), located 3.1 mi from the city center, is the airport you fly out of when you book flights from Ontario to Illinois.

What does ONT to ORD mean?

ONT and ORD are unique codes to identify airports used in the aviation industry. They are defined by IATA (International Air Transport Association) and are commonly called IATA codes. ONT to ORD refers to a flight route from Ontario Airport to Chicago O'Hare Intl Airport. Chicago Midway Airport (MDW), Moline Quad-City Airport (MLI), Greater Peoria Airport (PIA), Bloomington-Normal Airport (BMI), Springfield Capital Airport (SPI) are other airports near this flight route and their unique identifiers/IATA codes.

Can I find deals for flights from Ontario to Illinois that include extra baggage allowance?

The amount of baggage you can bring on your Ontario to Illinois flight depends on the airline and the type of fare you've chosen. After entering your flight details, you'll be able to view the specific baggage policies for each deal in the search results. Keep in mind that certain deals may offer additional baggage allowance.

Can I find deals on flights from Ontario to Illinois with specific airlines?

Yes, Cheapflights allows you to browse and filter Ontario to Illinois flight deals by airline. After entering your origin and destination, use the available filters to view flights offered by airlines.

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.

Can I find deals for flights from Ontario to Illinois that allow pets onboard?

Many airlines flying from Ontario to Illinois offer the option to travel with pets. After selecting a flight deal, you can find more information about the airline's pet policy on their official website or by contacting the airline directly. Please note that additional fees and restrictions may apply.

Can I find deals on last-minute flights from Ontario to Illinois?

Yes, you can often find last-minute deals on Ontario to Illinois flights on Cheapflights. However, these deals can vary and may not always be available. We recommend checking back frequently or signing up for price alerts for the most up-to-date deals.

Flights from Ontario, CA to Illinois (IL) from $62

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How far in advance should I book a flight from Ontario to Illinois?

To save up to 73% on this flight, we recommend booking at least 31 days prior to travel. The price may fluctuate and will likely increase closer to your departure date. Users on Cheapflights have found tickets from Ontario to Illinois from $319 1-2 weeks out and tickets from $510 for flights departing within the next 72 hours.

What is the cheapest month to fly from Ontario to Illinois?

Our data shows that January tends to be the cheapest month to fly to Illinois from Ontario. Users have commonly found prices around $314 for the month, but tickets can be as low as $135. Due to multiple factors, prepare for potentially higher prices in March.

When is the cheapest time to fly from Ontario to Illinois (ONT - IL)?

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

Cheap Delta flights from Ontario to Illinois

Check out some of the cheapest Delta flights we've come across from Ontario to Illinois. Come back soon if you're not finding the exact deal you're looking for.

Wed 6/511:22 amONT - ORD

1 stop10h 44mDelta

Wed 6/121:25 pmORD - ONT

2 stops11h 35mDelta

Deal found 5/13$241

Wed 6/56:00 amONT - ORD

2 stops12h 55mDelta

Wed 6/121:25 pmORD - ONT

2 stops11h 35mDelta

Deal found 5/13$246

Sat 8/1012:45 pmONT - MLI

1 stop7h 45mDelta

Wed 8/145:00 pmMLI - ONT

1 stop7h 12mDelta

Deal found 5/13$276

Tue 9/2412:45 pmONT - BMI

1 stop7h 45mDelta

Sat 9/286:00 amBMI - ONT

1 stop7h 22mDelta

Deal found 5/12$386

Thu 5/231:20 pmONT - ORD

1 stop6h 12mDelta

Thu 5/303:50 pmORD - ONT

2 stops9h 53mDelta

Deal found 5/12$405

Fri 8/2312:45 pmONT - MLI

1 stop7h 45mDelta

Sun 8/255:00 pmMLI - ONT

1 stop7h 12mDelta

Deal found 5/12$417

Sat 5/2512:50 pmONT - MLI

1 stop7h 26mDelta

Sun 5/266:00 amMLI - ONT

1 stop7h 40mDelta

Deal found 5/12$424

Thu 5/231:20 pmONT - ORD

1 stop6h 12mDelta

Sun 5/266:07 amORD - ONT

2 stops8h 06mDelta

Deal found 5/12$483

Mon 5/202:13 pmONT - ORD

1 stop7h 52mDelta

Wed 5/296:07 amORD - ONT

2 stops8h 06mDelta

Deal found 5/13$495

Cheap Frontier flights from Ontario to Illinois

Take a gander at the lowest prices we've found on Frontier flights from Ontario to Illinois. Deals are refreshing constantly so come back soon for more options.

Sat 6/112:59 amONT - STL

1 stop19h 33mFrontier

Fri 6/75:36 pmSTL - ONT

1 stop5h 47mFrontier

Deal found 5/13$125

Sun 6/211:30 pmONT - STL

1 stop8h 43mFrontier

Fri 6/75:36 pmSTL - ONT

1 stop5h 47mFrontier

Deal found 5/12$132

Mon 6/312:59 amONT - ORD

1 stop17h 51mFrontier

Wed 6/128:23 pmORD - ONT

1 stop12h 40mFrontier

Deal found 5/13$136

Sat 5/255:41 pmONT - ORD

1 stop9h 19mFrontier

Sat 6/15:56 pmORD - ONT

1 stop8h 03mFrontier

Deal found 5/13$137

Wed 8/218:35 pmONT - ORD

1 stop6h 12mFrontier

Thu 8/228:00 amORD - ONT

1 stop6h 15mFrontier

Deal found 5/12$138

Tue 8/1312:49 amONT - ORD

1 stop22h 14mFrontier

Wed 8/217:30 pmORD - ONT

1 stop13h 38mFrontier

Deal found 5/13$139

Wed 5/292:35 pmONT - ORD

1 stop8h 38mFrontier

Wed 6/58:23 pmORD - ONT

1 stop12h 40mFrontier

Deal found 5/12$140

Tue 5/2812:59 amONT - ORD

1 stop22h 14mFrontier

Sat 6/17:59 pmORD - ONT

1 stop13h 35mFrontier

Deal found 5/13$141

Sat 5/185:41 pmONT - STL

1 stop14h 32mFrontier

Mon 5/207:23 pmSTL - ONT

1 stop15h 41mFrontier

Deal found 5/13$142

Cheap Ontario to Illinois flights in May & June 2024

The lowest fares we've come across on flights traveling from Ontario to Illinois in May and June 2024. Check back regularly for other flight deals.

Sat 6/112:59 amONT - STL

1 stop19h 33mFrontier

Fri 6/75:36 pmSTL - ONT

1 stop5h 47mFrontier

Deal found 5/13$125

Sun 6/211:30 pmONT - STL

1 stop8h 43mFrontier

Fri 6/75:36 pmSTL - ONT

1 stop5h 47mFrontier

Deal found 5/12$132

Sat 6/112:59 amONT - STL

1 stop19h 33mFrontier

Fri 6/75:36 pmSTL - ONT

1 stop5h 47mFrontier

Deal found 5/12$136

Tue 5/1412:39 pmONT - STL

1 stop7h 20mFrontier

Sat 5/1811:41 pmSTL - ONT

1 stop8h 36mFrontier

Deal found 5/11$140

Tue 6/412:59 amONT - MDW

1 stop9h 01mFrontier

Sat 6/88:50 pmMDW - ONT

1 stop12h 13mFrontier

Deal found 5/12$140

Sat 5/185:41 pmONT - STL

1 stop14h 32mFrontier

Mon 5/207:23 pmSTL - ONT

1 stop15h 41mFrontier

Deal found 5/13$142

Wed 6/52:39 pmONT - MDW

1 stop12h 50mFrontier

Wed 6/125:55 amMDW - ONT

1 stop19h 54mFrontier

Deal found 5/12$144

Tue 5/212:25 pmONT - STL

1 stop17h 11mFrontier

Thu 5/237:23 pmSTL - ONT

1 stop25h 00mFrontier

Deal found 5/12$145

Wed 5/1512:39 pmONT - STL

1 stop19h 34mFrontier

Thu 5/167:23 pmSTL - ONT

1 stop25h 00mFrontier

Deal found 5/12$146

Ontario to Illinois 2024 flight deals

The lowest fares we've come across on flights traveling from Ontario to Illinois in May and June 2024. Check back regularly for other flight deals.

Sat 6/112:59 amONT - STL

1 stop19h 33mFrontier

Fri 6/75:36 pmSTL - ONT

1 stop5h 47mFrontier

Deal found 5/13$125

Sun 6/211:30 pmONT - STL

1 stop8h 43mFrontier

Fri 6/75:36 pmSTL - ONT

1 stop5h 47mFrontier

Deal found 5/12$132

Sat 6/112:59 amONT - STL

1 stop19h 33mFrontier

Fri 6/75:36 pmSTL - ONT

1 stop5h 47mFrontier

Deal found 5/12$136

Tue 5/1412:39 pmONT - STL

1 stop7h 20mFrontier

Sat 5/1811:41 pmSTL - ONT

1 stop8h 36mFrontier

Deal found 5/11$140

Tue 6/412:59 amONT - MDW

1 stop9h 01mFrontier

Sat 6/88:50 pmMDW - ONT

1 stop12h 13mFrontier

Deal found 5/12$140

Sat 5/185:41 pmONT - STL

1 stop14h 32mFrontier

Mon 5/207:23 pmSTL - ONT

1 stop15h 41mFrontier

Deal found 5/13$142

Mon 8/125:39 pmONT - MDW

1 stop16h 13mFrontier

Mon 8/1910:00 pmMDW - ONT

1 stop16h 47mFrontier

Deal found 5/12$142

Fri 8/1612:49 amONT - STL

1 stop6h 48mFrontier

Sun 8/183:53 pmSTL - ONT

1 stop9h 46mFrontier

Deal found 5/12$143

Fri 8/238:35 pmONT - MDW

1 stop7h 58mFrontier

Tue 8/276:00 amMDW - ONT

1 stop8h 32mFrontier

Deal found 5/12$143

Ontario to Illinois flights leaving soon

Users seeking a last-minute flight from Ontario to Illinois should consider booking one of these fares. It's wise to confirm all flight details are correct before booking.

Tue 5/2112:59 amONT - STL

1 stop6h 37mFrontier

Wed 5/2910:21 pmSTL - ONT

1 stop12h 19mFrontier

Deal found 5/12$140

Tue 5/2112:59 amONT - MDW

1 stop8h 10mFrontier

Wed 5/299:10 pmMDW - ONT

1 stop12h 14mFrontier

Deal found 5/12$140

Sat 5/185:41 pmONT - STL

1 stop14h 32mFrontier

Mon 5/207:23 pmSTL - ONT

1 stop15h 41mFrontier

Deal found 5/13$142

Tue 5/2112:59 amONT - MDW

1 stop8h 10mFrontier

Tue 5/289:10 pmMDW - ONT

1 stop20h 55mFrontier

Deal found 5/12$144

Tue 5/212:25 pmONT - STL

1 stop17h 11mFrontier

Thu 5/237:23 pmSTL - ONT

1 stop25h 00mFrontier

Deal found 5/12$145

Tue 5/212:25 pmONT - MDW

1 stop18h 44mFrontier

Wed 5/299:10 pmMDW - ONT

1 stop14h 24mFrontier

Deal found 5/12$146

Sat 5/1810:10 pmONT - STL

1 stop10h 03mFrontier

Mon 5/207:23 pmSTL - ONT

1 stop15h 41mFrontier

Deal found 5/11$147

Tue 5/2112:59 amONT - MDW

1 stop8h 10mFrontier

Tue 5/289:10 pmMDW - ONT

1 stop17h 45mFrontier

Deal found 5/12$147

Tue 5/2112:59 amONT - MDW

1 stop8h 10mFrontier

Wed 5/299:10 pmMDW - ONT

1 stop14h 24mFrontier

Deal found 5/12$148

One-way flights to Illinois from Ontario

Take a look at some of the one-way flights we've detected from Ontario to Illinois. For those needing a return trip from Ontario, there is a search form available above.

Tue 6/45:41 pmONT - MDW

1 stop8h 59mFrontier

Deal found 5/12$62

Tue 5/2110:42 pmONT - ORD

1 stop28h 18mFrontier

Deal found 5/12$62

Mon 6/1012:59 amONT - MDW

1 stop10h 10mFrontier

Deal found 5/12$63

Mon 6/1012:59 amONT - ORD

1 stop21h 41mFrontier

Deal found 5/12$63

Mon 6/108:46 pmONT - ORD

2 stops17h 16mMultiple Airlines

Deal found 5/12$69

Fri 8/3012:49 amONT - STL

1 stop6h 48mFrontier

Deal found 5/11$70

Tue 5/2112:59 amONT - MDW

1 stop8h 10mFrontier

Deal found 5/13$70

Tue 6/117:26 pmONT - ORD

1 stop7h 59mFrontier

Deal found 5/13$70

Tue 6/117:26 pmONT - MDW

1 stop7h 07mFrontier

Deal found 5/12$71

Find flights from Ontario to Illinois within your budget

Fly from

Fly to

Budget

$125 - $335

Route

Depart

Return

Price

OntarioLambert-St Louis

ONT - STL

ONTSTL

Ontario

Sat 6/1

1 stop19h 33m

Lambert-St Louis

Fri 6/7

1 stop5h 47m

$125

OntarioLambert-St Louis

ONT - STL

ONTSTL

Ontario

Sun 6/2

1 stop8h 43m

Lambert-St Louis

Fri 6/7

1 stop5h 47m

$132

OntarioLambert-St Louis

ONT - STL

ONTSTL

Ontario

Sat 6/1

1 stop19h 33m

Lambert-St Louis

Fri 6/7

1 stop5h 47m

$136

OntarioChicago O'Hare Intl

ONT - ORD

ONTORD

Ontario

Mon 6/3

1 stop17h 51m

Chicago O'Hare Intl

Wed 6/12

1 stop12h 40m

$136

OntarioChicago O'Hare Intl

ONT - ORD

ONTORD

Ontario

Sat 5/25

1 stop9h 19m

Chicago O'Hare Intl

Sat 6/1

1 stop8h 03m

$137

OntarioChicago O'Hare Intl

ONT - ORD

ONTORD

Ontario

Wed 8/21

1 stop6h 12m

Chicago O'Hare Intl

Thu 8/22

1 stop6h 15m

$138

OntarioChicago O'Hare Intl

ONT - ORD

ONTORD

Ontario

Wed 6/5

1 stop10h 44m

Chicago O'Hare Intl

Wed 6/12

2 stops11h 35m

$241

OntarioChicago O'Hare Intl

ONT - ORD

ONTORD

Ontario

Tue 6/4

1 stop6h 31m

Chicago O'Hare Intl

Tue 6/11

2 stops17h 58m

$277

OntarioMoline Quad-City

ONT - MLI

ONTMLI

Ontario

Sat 5/25

1 stop6h 21m

Moline Quad-City

Sat 6/1

2 stops9h 33m

$335

Flights are sorted by cheapest first

Deals found on 5/13

No data available for this route at this time. Please check back soon.

Reviews of airlines servicing Illinois

Get a feel of what it's like to fly with Delta, Frontier and American Airlines from Ontario to Illinois by reading reviews from past customers. In addition to providing an overall rating, users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.

Alaska Airlines

8.1

Very good

9,144 reviews

Check prices

Reviews

1 / 10

Paid a lot for our exit row seats and they weren’t that roomy.

Alaska Airlines

8.1

Very good

9,144 reviews

Alaska Airlines

8.1

Very good

9,144 reviews

Check prices

Reviews

1 / 10

Paid a lot for our exit row seats and they weren’t that roomy.

Delta

8.0

Very good

10,736 reviews

Alaska Airlines

8.1

Very good

9,144 reviews

Check prices

Reviews

1 / 10

Paid a lot for our exit row seats and they weren’t that roomy.

United Airlines

7.4

Good

10,980 reviews

Alaska Airlines

8.1

Very good

9,144 reviews

Check prices

Reviews

1 / 10

Paid a lot for our exit row seats and they weren’t that roomy.

American Airlines

7.3

Good

14,575 reviews

Alaska Airlines

8.1

Very good

9,144 reviews

Check prices

Reviews

1 / 10

Paid a lot for our exit row seats and they weren’t that roomy.

Volaris

6.7

Okay

1,501 reviews

Alaska Airlines

8.1

Very good

9,144 reviews

Check prices

Reviews

1 / 10

Paid a lot for our exit row seats and they weren’t that roomy.

Related info for your journey

What airport do you fly from for flights from Ontario to Illinois?
Ontario (ONT), located 3.1 mi from the city center, is the airport you fly out of when you book flights from Ontario to Illinois.
Can I find flights from Ontario to Illinois for under $200 on Cheapflights?
Yes, there are multiple flights from Ontario to Illinois for under $200. The cheapest flight booked recently is on Frontier for just $125, but on average you can expect to pay $140.
Are there last-minute flights available from Ontario to Illinois for under $200?
There are currently 20+ open flights from Ontario to Illinois within the next 7 days for less than $200.
What are the most popular routes from Ontario to Illinois?
The most popular flight routes from Ontario to Illinois are Ontario - Chicago O'Hare Intl, Ontario - Chicago Midway and Ontario - Lambert-St Louis.
What are the most popular airlines that fly from Ontario to Illinois?
Consider American Airlines, Delta or Frontier when booking your flight. These represent the most popular airlines when flying from Ontario to Illinois.
What does ONT to ORD mean?
ONT and ORD are unique codes to identify airports used in the aviation industry. They are defined by IATA (International Air Transport Association) and are commonly called IATA codes. ONT to ORD refers to a flight route from Ontario Airport to Chicago O'Hare Intl Airport. Chicago Midway Airport (MDW), Moline Quad-City Airport (MLI), Greater Peoria Airport (PIA), Bloomington-Normal Airport (BMI), Springfield Capital Airport (SPI) are other airports near this flight route and their unique identifiers/IATA codes.
Can I find deals for flights from Ontario to Illinois that include extra baggage allowance?
The amount of baggage you can bring on your Ontario to Illinois flight depends on the airline and the type of fare you've chosen. After entering your flight details, you'll be able to view the specific baggage policies for each deal in the search results. Keep in mind that certain deals may offer additional baggage allowance.
Can I find deals on flights from Ontario to Illinois with specific airlines?
Yes, Cheapflights allows you to browse and filter Ontario to Illinois flight deals by airline. After entering your origin and destination, use the available filters to view flights offered by airlines.
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.
Can I find deals for flights from Ontario to Illinois that allow pets onboard?
Many airlines flying from Ontario to Illinois offer the option to travel with pets. After selecting a flight deal, you can find more information about the airline's pet policy on their official website or by contacting the airline directly. Please note that additional fees and restrictions may apply.
Can I find deals on last-minute flights from Ontario to Illinois?
Yes, you can often find last-minute deals on Ontario to Illinois flights on Cheapflights. However, these deals can vary and may not always be available. We recommend checking back frequently or signing up for price alerts for the most up-to-date deals.
How recently were the Ontario to Illinois flight deals updated?
The Ontario to Illinois flight deals you see on this page were last updated on 5/13.

See more FAQs

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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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Complete your trip
Complete your trip to Illinois by adding a car rental and/or hotel reservation to your travel itinerary.

Illinois car rentals

Chicago O'Hare Intl Airport car rentals

Chicago Midway Airport car rentals

Moline Quad-City Airport car rentals

Greater Peoria Airport car rentals

Bloomington-Normal Airport car rentals

Springfield Capital Airport car rentals

Champaign University-Willard Airport car rentals

Chicago Greater Rockford Airport car rentals

Belleville Airport car rentals

Marion Williamson County Airport car rentals

Quincy Regional Airport car rentals

Top 5 airlines flying from Ontario to Illinois

Airline	Cheapest	Average	Flexibility	On-time
Spirit Airlines	Cheapest$105	Average$261	FlexibilityNo cancel fee	On-time65%	Search Spirit Airlines flights
Frontier	Cheapest$122	Average$228	FlexibilityNo cancel fee	On-time62%	Search Frontier flights
United Airlines	Cheapest$245	Average$522	FlexibilityNo cancel fee	On-time69%	Search United Airlines flights
Delta	Cheapest$276	Average$431	FlexibilityNo cancel fee	On-timeN/A	Search Delta flights
American Airlines	Cheapest$297	Average$623	FlexibilityNo cancel fee	On-time71%	Search American Airlines flights

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Ontario to Indiana flights

Search flights from Ontario to Illinois by cabin class

Hourly flight availability from Ontario to Illinois

0%of flight departures	Early morningMidnight to 6 am
100%of flight departures	Morning6 am to noon
0%of flight departures	AfternoonNoon to 6 pm
0%of flight departures	Evening6 pm to midnight

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How does Cheapflights help users find flights from Ontario to Illinois?

Cheapflights goes through 900+ travel sites to look for the best flight deals for flights from Ontario to Illinois. Too many options? Cheapflights also provides filters for things like airlines, price ranges, and number of stops to help you make a decision easily.

Why should you use Cheapflights to find cheap flight tickets from Ontario to Illinois?

Millions of users choose and trust Cheapflights to book the best flight deals from Ontario to Illinois for free. We help you search and compare prices from hundreds of airlines for the right flight just for you.

Can Cheapflights find flights from Ontario to Illinois with no change fees?

Yes! Cheapflights helps users easily find flights from Ontario to Illinois with no change fees.

Can Cheapflights notify me if prices for flights from Ontario to Illinois become cheaper?

Not ready to book yet? You can track prices for flights from Ontario to Illinois on Cheapflights with our Price Alert feature and get notified when better prices are available.

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Cheap flights from Ontario (ONT) to Illinois from $62

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 6/4. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.

How far in advance should I book a flight from Ontario to Illinois?

What is the cheapest month to fly from Ontario to Illinois?

When is the cheapest time to fly from Ontario to Illinois (ONT - IL)?

Cheap Delta flights from Ontario to Illinois

Check out some of the cheapest Delta flights we've come across from Ontario to Illinois. Come back soon if you're not finding the exact deal you're looking for.

Cheap Frontier flights from Ontario to Illinois

Take a gander at the lowest prices we've found on Frontier flights from Ontario to Illinois. Deals are refreshing constantly so come back soon for more options.

Cheap Ontario to Illinois flights in May & June 2024

Find cheap flight options from Ontario to Illinois specifically for the months of May and June 2024. Explore affordable fares based on user searches. Over the last 7 days, Cheapflights users made 2,633,403 searches. Prices were last updated on May 13, 2024.

The lowest fares we've come across on flights traveling from Ontario to Illinois in May and June 2024. Check back regularly for other flight deals.

Ontario to Illinois 2024 flight deals

Discover exclusive flight deals for travel between Ontario and Illinois in 2024. Find excellent offers based on user searches. Over the last 7 days, Cheapflights users made 2,633,403 searches. Data last updated May 13, 2024.

The lowest fares we've come across on flights traveling from Ontario to Illinois in May and June 2024. Check back regularly for other flight deals.

Ontario to Illinois flights leaving soon

Users seeking a last-minute flight from Ontario to Illinois should consider booking one of these fares. It's wise to confirm all flight details are correct before booking.

One-way flights to Illinois from Ontario

Take a look at some of the one-way flights we've detected from Ontario to Illinois. For those needing a return trip from Ontario, there is a search form available above.

Find flights from Ontario to Illinois within your budget

Reviews of airlines servicing Illinois

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.

What airport do you fly from for flights from Ontario to Illinois?

Can I find flights from Ontario to Illinois for under $200 on Cheapflights?

Are there last-minute flights available from Ontario to Illinois for under $200?

What are the most popular routes from Ontario to Illinois?

What are the most popular airlines that fly from Ontario to Illinois?

What does ONT to ORD mean?

Can I find deals for flights from Ontario to Illinois that include extra baggage allowance?

Can I find deals on flights from Ontario to Illinois with specific airlines?

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

How can I find direct flights from Ontario to Illinois?

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

Can I find deals for flights from Ontario to Illinois that allow pets onboard?

Can I find deals on last-minute flights from Ontario to Illinois?

How recently were the Ontario to Illinois flight deals updated?

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Alternative routes for Ontario to IllinoisSee prices for flight routes from nearby airports that may be better suited for you.

See prices for flight routes from nearby airports that may be better suited for you.

Top 5 airlines flying from Ontario to Illinois

Popular flight searches

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Search flights from Ontario to Illinois by cabin class

Find flights from Ontario to Illinois, based on your preferred cabin class, be it economy, premium economy, business, or first class.

Hourly flight availability from Ontario to Illinois

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 May 13, 2024.

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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.