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Cheap flights from Ontario (ONT) to Illinois from $67

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 8/21. 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.
ONT — ORD
Jun 16 — Jun 231
From?
To?
Sun 6/16
Sun 6/23
1 adult, Economy
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How far in advance should I book a flight from Ontario to Illinois?

To save up to 71% on this flight, we recommend booking at least 60 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 $507 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 $313 for the month, but tickets can be as low as $135. Due to multiple factors, prepare for potentially higher prices in March.

What is the cheapest time of day to fly from ONT to 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 Ontario to Illinois flights in June & July 2024

Find cheap flight options from Ontario to Illinois specifically for the months of June and July 2024. Explore affordable fares based on user searches. Over the last 7 days, Cheapflights users made 3,117,830 searches. Prices were last updated on June 11, 2024.
The lowest fares we've come across on flights traveling from Ontario to Illinois in June and July 2024. Check back regularly for other flight deals.
Mon 6/178:46 pmONT - STL
1 stop11h 56mFrontier
Mon 6/248:22 pmSTL - ONT
1 stop13h 05mFrontier
Deal found 6/9$137
Mon 6/1712:54 pmONT - STL
1 stop19h 48mFrontier
Wed 6/197:29 pmSTL - ONT
1 stop13h 34mFrontier
Deal found 6/10$143
Mon 7/227:04 pmONT - MDW
1 stop8h 29mFrontier
Wed 7/3112:23 pmMDW - ONT
1 stop5h 42mFrontier
Deal found 6/10$150
Mon 7/812:49 amONT - MDW
1 stop14h 21mFrontier
Wed 7/1712:23 pmMDW - ONT
1 stop5h 42mFrontier
Deal found 6/9$151
Wed 7/1010:05 pmONT - MDW
1 stop28h 40mFrontier
Wed 7/1712:23 pmMDW - ONT
1 stop5h 42mFrontier
Deal found 6/10$153
Mon 6/248:46 pmONT - MDW
1 stop6h 43mFrontier
Tue 6/258:02 pmMDW - ONT
1 stop15h 02mFrontier
Deal found 6/10$156
Mon 6/249:36 pmONT - ORD
1 stop25h 04mFrontier
Tue 7/26:00 amORD - ONT
1 stop19h 59mFrontier
Deal found 6/10$156
Mon 6/249:36 pmONT - ORD
1 stop25h 04mFrontier
Tue 7/26:00 amORD - ONT
1 stop19h 59mFrontier
Deal found 6/10$157
Sat 6/229:35 pmONT - MDW
1 stop5h 46mFrontier
Tue 7/22:06 pmMDW - ONT
1 stop11h 53mFrontier
Deal found 6/10$158

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 3,117,830 searches. Data last updated June 11, 2024.
The lowest fares we've come across on flights traveling from Ontario to Illinois in June and July 2024. Check back regularly for other flight deals.
Sun 9/1511:22 pmONT - STL
1 stop8h 56mFrontier
Tue 9/247:29 pmSTL - ONT
1 stop24h 40mFrontier
Deal found 6/10$136
Sat 8/246:57 amONT - MDW
1 stop6h 56mFrontier
Tue 9/1011:32 amMDW - ONT
1 stop7h 18mFrontier
Deal found 6/11$136
Thu 8/155:30 pmONT - ORD
1 stop9h 17mFrontier
Sat 8/245:56 pmORD - ONT
1 stop7h 48mFrontier
Deal found 6/10$136
Mon 6/178:46 pmONT - STL
1 stop11h 56mFrontier
Mon 6/248:22 pmSTL - ONT
1 stop13h 05mFrontier
Deal found 6/9$137
Tue 8/208:35 pmONT - MDW
1 stop7h 58mFrontier
Wed 8/2810:00 pmMDW - ONT
1 stop11h 08mFrontier
Deal found 6/10$137
Sat 8/178:35 pmONT - ORD
1 stop6h 12mFrontier
Sat 8/245:56 pmORD - ONT
1 stop7h 48mFrontier
Deal found 6/10$137
Mon 8/1212:49 amONT - MDW
1 stop9h 03mFrontier
Wed 8/2110:00 pmMDW - ONT
1 stop11h 08mFrontier
Deal found 6/10$138
Fri 8/1612:49 amONT - ORD
1 stop21h 22mFrontier
Sat 8/247:30 pmORD - ONT
1 stop13h 38mFrontier
Deal found 6/10$138
Tue 8/136:57 amONT - MDW
1 stop12h 05mFrontier
Wed 8/2111:32 amMDW - ONT
1 stop6h 26mFrontier
Deal found 6/10$139

Ontario to Illinois flights leaving soon

Find last-minute flight options from Ontario to Illinois for spontaneous travel. Discover available flights and compare prices based on user searches. Secure great deals and offers for spontaneous trips with quick booking options. Over the last 7 days, Cheapflights users made 3,117,830 searches. Data last updated June 11, 2024.
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.
Mon 6/178:46 pmONT - STL
1 stop11h 56mFrontier
Mon 6/248:22 pmSTL - ONT
1 stop13h 05mFrontier
Deal found 6/9$137
Mon 6/1712:54 pmONT - STL
1 stop19h 48mFrontier
Wed 6/197:29 pmSTL - ONT
1 stop13h 34mFrontier
Deal found 6/10$143
Mon 6/179:36 pmONT - MDW
1 stop17h 34mFrontier
Wed 6/268:58 pmMDW - ONT
1 stop12h 05mFrontier
Deal found 6/10$177
Fri 6/2112:49 amONT - ORD
1 stop18h 17mFrontier
Sun 6/306:00 amORD - ONT
1 stop19h 59mFrontier
Deal found 6/10$180
Fri 6/2110:26 pmONT - MDW
1 stop10h 35mFrontier
Sun 6/238:15 pmMDW - ONT
1 stop14h 49mFrontier
Deal found 6/10$188
Fri 6/2110:23 pmONT - ORD
1 stop20h 43mFrontier
Sun 6/238:23 pmORD - ONT
1 stop14h 41mFrontier
Deal found 6/10$188
Thu 6/209:40 pmONT - STL
1 stop11h 02mFrontier
Tue 7/97:49 pmSTL - ONT
1 stop21h 13mFrontier
Deal found 6/10$191
Wed 6/198:55 pmONT - MDW
1 stop6h 34mFrontier
Wed 6/2611:26 amMDW - ONT
1 stop7h 11mFrontier
Deal found 6/10$195
Tue 6/1812:59 amONT - MDW
1 stop9h 01mFrontier
Wed 6/2611:26 amMDW - ONT
1 stop7h 11mFrontier
Deal found 6/10$196

One-way flights to Illinois from Ontario

Search for one-way flight options from Ontario to Illinois. Find affordable one-way fares based on user searches. Compare prices and availability to plan your one-way journey according to your preferred dates and budget. Over the last 7 days, Cheapflights users made 3,117,830 searches. Data last updated June 11, 2024.
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.
Wed 8/216:57 amONT - MDW
1 stop7h 02mFrontier
Deal found 6/11$67
Wed 8/288:35 pmONT - ORD
1 stop6h 12mFrontier
Deal found 6/10$67
Sun 8/1112:59 amONT - STL
1 stop6h 26mFrontier
Deal found 6/10$68
Mon 8/198:35 pmONT - MDW
1 stop7h 58mFrontier
Deal found 6/11$68
Wed 8/148:35 pmONT - ORD
1 stop6h 12mFrontier
Deal found 6/10$68
Fri 9/138:35 pmONT - MDW
1 stop7h 58mFrontier
Deal found 6/10$70
Mon 6/178:46 pmONT - STL
1 stop11h 56mFrontier
Deal found 6/10$73
Tue 8/201:32 pmONT - MDW
1 stop20h 20mFrontier
Deal found 6/11$73
Tue 8/2712:49 amONT - ORD
1 stop22h 14mFrontier
Deal found 6/10$73

Find flights from Ontario to Illinois within your budget

Customize your flight search to find flights from Ontario to Illinois 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 3,117,830 searches. Data last updated June 11, 2024.

Fly from

Any airport

Fly to

Any airport

Budget

$136 - $362

Route

Depart

Return

Price

OntarioLambert-St Louis

ONT - STL

ONTSTL

Ontario

Sun 9/15

1 stop8h 56m

Lambert-St Louis

Tue 9/24

1 stop24h 40m

$136

OntarioChicago Midway

ONT - MDW

ONTMDW

Ontario

Sat 8/24

1 stop6h 56m

Chicago Midway

Tue 9/10

1 stop7h 18m

$136

OntarioChicago O'Hare Intl

ONT - ORD

ONTORD

Ontario

Thu 8/15

1 stop9h 17m

Chicago O'Hare Intl

Sat 8/24

1 stop7h 48m

$136

OntarioLambert-St Louis

ONT - STL

ONTSTL

Ontario

Tue 9/24

1 stop6h 48m

Lambert-St Louis

Wed 10/2

1 stop5h 39m

$137

OntarioChicago Midway

ONT - MDW

ONTMDW

Ontario

Tue 8/20

1 stop7h 58m

Chicago Midway

Wed 8/28

1 stop11h 08m

$137

OntarioChicago O'Hare Intl

ONT - ORD

ONTORD

Ontario

Wed 8/21

1 stop10h 07m

Chicago O'Hare Intl

Tue 8/27

2 stops10h 09m

$241

OntarioChicago O'Hare Intl

ONT - ORD

ONTORD

Ontario

Tue 8/13

2 stops11h 56m

Chicago O'Hare Intl

Wed 8/21

1 stop6h 51m

$247

OntarioChicago O'Hare Intl

ONT - ORD

ONTORD

Ontario

Thu 7/4

1 stop5h 47m

Chicago O'Hare Intl

Fri 7/12

1 stop5h 24m

$260

OntarioLambert-St Louis

ONT - STL

ONTSTL

Ontario

Sat 8/31

1 stop5h 28m

Lambert-St Louis

Sun 9/1

2 stops14h 57m

$362

Flights are sorted by cheapest first

Deals found on 6/10

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

Best time to book a flight from Ontario to Illinois

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

Reviews of airlines servicing Illinois

Get insights into the airlines that provide service to Illinois. 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 Illinois. Reviews last updated June 11, 2024.
Get a feel of what it's like to fly with Delta, American Airlines and Frontier 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.
Southwest
8.2
Very good
5,889 reviews

Overall

8.2

Crew

8.7

Food

7.3

Entertainment

7.8

Comfort

8.1

Boarding

8.3

Reviews

1 / 10

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

Southwest
8.2
Very good
5,889 reviews
Southwest
8.2
Very good
5,889 reviews

Overall

8.2

Crew

8.7

Food

7.3

Entertainment

7.8

Comfort

8.1

Boarding

8.3

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
8.1
Very good
9,267 reviews
Southwest
8.2
Very good
5,889 reviews

Overall

8.2

Crew

8.7

Food

7.3

Entertainment

7.8

Comfort

8.1

Boarding

8.3

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
10,277 reviews
Southwest
8.2
Very good
5,889 reviews

Overall

8.2

Crew

8.7

Food

7.3

Entertainment

7.8

Comfort

8.1

Boarding

8.3

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
10,629 reviews
Southwest
8.2
Very good
5,889 reviews

Overall

8.2

Crew

8.7

Food

7.3

Entertainment

7.8

Comfort

8.1

Boarding

8.3

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
7.3
Good
14,129 reviews
Southwest
8.2
Very good
5,889 reviews

Overall

8.2

Crew

8.7

Food

7.3

Entertainment

7.8

Comfort

8.1

Boarding

8.3

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 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?

    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 $136, but on average you can expect to pay $139.

  • 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 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 6/11.

  • 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 is the cheapest month to book a flight from Ontario to Illinois?

    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 July is currently the most expensive (average of $324). 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 Illinois
See prices for flight routes from nearby airports that may be better suited for you.

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Top 5 airlines flying from Ontario to Illinois

Discover the top 5 airlines that operate flights from Ontario to Illinois. 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 3,117,830 searches. Data last updated June 11, 2024.
AirlineCheapestAverageFlexibilityOn-time
Spirit AirlinesCheapest$93Average$251FlexibilityNo cancel feeOn-time65%
FrontierCheapest$123Average$237FlexibilityNo cancel feeOn-time62%
United AirlinesCheapest$268Average$509FlexibilityNo cancel feeOn-time69%
DeltaCheapest$276Average$419FlexibilityNo cancel feeOn-timeN/A
American AirlinesCheapest$288Average$617FlexibilityNo cancel feeOn-time71%
Boston to Cancún flights
Dallas to San Antonio flights
Reno to Las Vegas flights
Houston to Boston flights
San Francisco to Las Vegas flights
Newark Airport to Fort Lauderdale flights
Los Angeles to Dubai flights
USA to Hyderabad flights
Boston to Phoenix flights
Phoenix to Las Vegas flights
Houston to Paris flights
Ontario to Indiana flights

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.
First Class
Business Class
Prem Econ Class
Economy 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 June 11, 2024.
80%of flight departuresEarly morningMidnight to 6 am
20%of flight departuresMorning6 am to noon
0%of flight departuresAfternoonNoon to 6 pm
0%of flight departuresEvening6 pm to midnight
Midnight
6 AM
Noon
6 PM

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