Cheap flights from Ontario (ONT) to Illinois from $45
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 5/14. 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
Apr 23 — Apr 301
From?
To?
1 adult, Economy
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How far in advance should I book a flight from Ontario to Illinois?
To save up to 79% on this flight, we recommend booking at least 46 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 $297 1-2 weeks out and tickets from $499 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 $302 for the month, but tickets can be as low as $93. Due to multiple factors, prepare for potentially higher prices in June.
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 Alaska Airlines flights from Ontario to Illinois
Explore cheap flight options specifically provided by Alaska Airlines for the route between Ontario and Illinois. Find affordable fares and compare prices with other airlines to secure the best deal for your journey. Over the last 7 days, Cheapflights users made 3,192,047 searches. Data last updated April 18, 2024.
Check out some of the cheapest Alaska Airlines flights we've come across from Ontario to Illinois. Come back soon if you're not finding the exact deal you're looking for.
Sat 4/277:00 amONT - ORD
2 stops14h 58mAlaska Airlines
Tue 4/308:00 amORD - ONT
1 stop10h 05mAlaska Airlines
Deal found 4/18$493
Tue 5/147:00 amONT - STL
2 stops14h 59mAlaska Airlines
Thu 5/167:00 amSTL - ONT
1 stop28h 05mAlaska Airlines
Deal found 4/18$497
Sun 4/286:00 amONT - ORD
2 stops20h 45mAlaska Airlines
Mon 4/295:46 pmORD - ONT
1 stop8h 13mAlaska Airlines
Deal found 4/18$498
Sat 4/276:00 amONT - ORD
1 stop8h 47mAlaska Airlines
Sat 5/48:35 amORD - ONT
2 stops14h 53mAlaska Airlines
Deal found 4/18$541
Sat 5/117:00 amONT - STL
2 stops14h 59mAlaska Airlines
Thu 5/167:00 amSTL - ONT
1 stop14h 14mAlaska Airlines
Deal found 4/17$552
Cheap American Airlines flights from Ontario to Illinois
Explore cheap flight options specifically provided by American Airlines for the route between Ontario and Illinois. Find affordable fares and compare prices with other airlines to secure the best deal for your journey. Over the last 7 days, Cheapflights users made 3,192,047 searches. Data last updated April 18, 2024.
Take a gander at the lowest prices we've found on American Airlines flights from Ontario to Illinois. Deals are refreshing constantly so come back soon for more options.
Wed 5/1512:53 pmONT - STL
2 stops8h 06mAmerican Airlines
Tue 5/286:18 pmSTL - ONT
1 stop6h 11mAmerican Airlines
Deal found 4/18$349
Wed 8/144:45 pmONT - STL
1 stop5h 04mAmerican Airlines
Sat 8/175:54 amSTL - ONT
2 stops7h 50mAmerican Airlines
Deal found 4/18$369
Wed 4/2410:00 amONT - ORD
1 stop5h 42mAmerican Airlines
Tue 4/3012:02 pmORD - ONT
2 stops8h 43mAmerican Airlines
Deal found 4/18$380
Thu 5/2312:25 pmONT - STL
2 stops8h 34mAmerican Airlines
Tue 5/286:18 pmSTL - ONT
1 stop6h 11mAmerican Airlines
Deal found 4/18$386
Thu 8/86:32 amONT - PIA
1 stop5h 45mAmerican Airlines
Sat 8/107:22 amPIA - ONT
1 stop6h 02mAmerican Airlines
Deal found 4/18$412
Thu 8/86:32 amONT - PIA
1 stop5h 45mAmerican Airlines
Sat 8/107:30 amPIA - ONT
2 stops10h 17mAmerican Airlines
Deal found 4/18$415
Sat 4/276:00 amONT - PIA
1 stop6h 43mAmerican Airlines
Wed 5/16:30 amPIA - ONT
1 stop9h 23mAmerican Airlines
Deal found 4/16$805
Tue 4/2312:53 pmONT - BMI
1 stop6h 14mAmerican Airlines
Mon 4/297:00 amBMI - ONT
2 stops13h 49mAmerican Airlines
Deal found 4/17$862
Cheap Ontario to Illinois flights in April & May 2024
Find cheap flight options from Ontario to Illinois specifically for the months of April and May 2024. Explore affordable fares based on user searches. Over the last 7 days, Cheapflights users made 3,192,047 searches. Prices were last updated on April 18, 2024.
The lowest fares we've come across on flights traveling from Ontario to Illinois in April and May 2024. Check back regularly for other flight deals.
Mon 5/1310:59 pmONT - STL
1 stop9h 10mFrontier
Sat 5/188:04 pmSTL - ONT
1 stop5h 55mFrontier
Deal found 4/17$75
Fri 5/1012:55 amONT - STL
1 stop6h 52mFrontier
Thu 5/165:01 pmSTL - ONT
1 stop27h 22mFrontier
Deal found 4/17$87
Thu 5/910:58 pmONT - MDW
1 stop10h 38mFrontier
Sat 5/189:05 pmMDW - ONT
1 stop12h 24mFrontier
Deal found 4/17$87
Sat 5/1110:56 pmONT - STL
1 stop9h 22mFrontier
Thu 5/1611:06 pmSTL - ONT
1 stop26h 53mFrontier
Deal found 4/17$88
Mon 5/1312:59 amONT - STL
1 stop12h 51mFrontier
Thu 5/167:23 pmSTL - ONT
1 stop25h 00mFrontier
Deal found 4/17$89
Mon 5/1312:59 amONT - MDW
1 stop19h 06mFrontier
Sat 5/185:05 amMDW - ONT
1 stop20h 54mFrontier
Deal found 4/18$89
Thu 5/910:58 pmONT - STL
1 stop9h 20mFrontier
Sat 5/1112:39 pmSTL - ONT
1 stop6h 20mFrontier
Deal found 4/18$90
Fri 5/1012:55 amONT - MDW
1 stop17h 44mFrontier
Mon 5/1310:59 pmMDW - ONT
1 stop24h 58mFrontier
Deal found 4/18$90
Sat 5/187:04 amONT - MDW
1 stop12h 34mFrontier
Mon 5/205:11 amMDW - ONT
1 stop20h 48mFrontier
Deal found 4/18$91
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 3,192,047 searches. Data last updated April 18, 2024.
The lowest fares we've come across on flights traveling from Ontario to Illinois in April and May 2024. Check back regularly for other flight deals.
Mon 5/1310:59 pmONT - STL
1 stop9h 10mFrontier
Sat 5/188:04 pmSTL - ONT
1 stop5h 55mFrontier
Deal found 4/17$75
Fri 5/1012:55 amONT - STL
1 stop6h 52mFrontier
Thu 5/165:01 pmSTL - ONT
1 stop27h 22mFrontier
Deal found 4/17$87
Thu 5/910:58 pmONT - MDW
1 stop10h 38mFrontier
Sat 5/189:05 pmMDW - ONT
1 stop12h 24mFrontier
Deal found 4/17$87
Sat 5/1110:56 pmONT - STL
1 stop9h 22mFrontier
Thu 5/1611:06 pmSTL - ONT
1 stop26h 53mFrontier
Deal found 4/17$88
Mon 5/1312:59 amONT - STL
1 stop12h 51mFrontier
Thu 5/167:23 pmSTL - ONT
1 stop25h 00mFrontier
Deal found 4/17$89
Mon 5/1312:59 amONT - MDW
1 stop19h 06mFrontier
Sat 5/185:05 amMDW - ONT
1 stop20h 54mFrontier
Deal found 4/18$89
Thu 5/910:58 pmONT - STL
1 stop9h 20mFrontier
Sat 5/1112:39 pmSTL - ONT
1 stop6h 20mFrontier
Deal found 4/18$90
Fri 5/1012:55 amONT - MDW
1 stop17h 44mFrontier
Mon 5/1310:59 pmMDW - ONT
1 stop24h 58mFrontier
Deal found 4/18$90
Sat 5/187:04 amONT - MDW
1 stop12h 34mFrontier
Mon 5/205:11 amMDW - ONT
1 stop20h 48mFrontier
Deal found 4/18$91
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 3,192,047 searches. Data last updated April 18, 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.
Wed 5/17:41 pmONT - MDW
1 stop13h 55mFrontier
Sat 5/1110:30 amMDW - ONT
1 stop22h 01mFrontier
Deal found 4/18$100
Tue 4/306:55 pmONT - MDW
1 stop14h 41mFrontier
Sat 5/1110:59 pmMDW - ONT
1 stop10h 04mFrontier
Deal found 4/16$102
Mon 4/2912:59 amONT - MDW
1 stop8h 39mFrontier
Sat 5/119:29 pmMDW - ONT
1 stop11h 02mFrontier
Deal found 4/16$103
Thu 5/210:58 pmONT - MDW
1 stop10h 38mFrontier
Thu 5/95:01 amMDW - ONT
1 stop13h 59mFrontier
Deal found 4/18$104
Mon 4/2912:59 amONT - MDW
1 stop8h 39mFrontier
Sat 5/119:29 pmMDW - ONT
1 stop11h 02mFrontier
Deal found 4/18$105
Tue 4/3012:59 amONT - MDW
1 stop8h 39mFrontier
Tue 5/219:10 pmMDW - ONT
1 stop13h 54mFrontier
Deal found 4/17$106
Tue 4/3012:59 amONT - MDW
1 stop8h 39mFrontier
Tue 5/1410:55 pmMDW - ONT
1 stop9h 31mFrontier
Deal found 4/18$107
Tue 4/3012:59 amONT - MDW
1 stop8h 39mFrontier
Sat 5/185:05 amMDW - ONT
1 stop20h 54mFrontier
Deal found 4/18$108
Wed 5/17:41 pmONT - MDW
1 stop13h 55mFrontier
Mon 5/1310:59 pmMDW - ONT
1 stop10h 04mFrontier
Deal found 4/18$112
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 3,192,047 searches. Data last updated April 18, 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.
Tue 5/1412:59 amONT - MDW
1 stop8h 39mFrontier
Deal found 4/18$45
Tue 5/712:59 amONT - MDW
1 stop8h 39mFrontier
Deal found 4/17$48
Thu 5/910:58 pmONT - STL
1 stop9h 20mFrontier
Deal found 4/18$51
Tue 5/1410:49 pmONT - MDW
1 stop10h 47mFrontier
Deal found 4/18$51
Mon 5/204:31 pmONT - MDW
1 stop21h 06mFrontier
Deal found 4/17$53
Wed 5/810:49 pmONT - MDW
1 stop10h 47mFrontier
Deal found 4/18$54
Tue 5/712:39 pmONT - STL
1 stop7h 20mFrontier
Deal found 4/18$59
Mon 4/2912:59 amONT - MDW
1 stop8h 39mFrontier
Deal found 4/16$59
Wed 4/2412:59 amONT - STL
1 stop7h 39mFrontier
Deal found 4/18$60
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 3,192,047 searches. Data last updated April 18, 2024.
Fly from
Any airport
Fly to
Any airport
Budget
$87 - $264
Route
Depart
Return
Price
OntarioLambert-St Louis
ONT - STL
ONTSTL
Ontario
Fri 5/10
1 stop6h 52m
Lambert-St Louis
Thu 5/16
1 stop27h 22m
$87
OntarioChicago Midway
ONT - MDW
ONTMDW
Ontario
Mon 5/13
1 stop19h 06m
Chicago Midway
Tue 5/21
1 stop9h 24m
$87
OntarioLambert-St Louis
ONT - STL
ONTSTL
Ontario
Sat 5/11
1 stop12h 17m
Lambert-St Louis
Thu 5/16
1 stop26h 53m
$88
OntarioChicago Midway
ONT - MDW
ONTMDW
Ontario
Tue 5/14
1 stop8h 39m
Chicago Midway
Mon 5/20
1 stop13h 54m
$88
OntarioLambert-St Louis
ONT - STL
ONTSTL
Ontario
Fri 5/10
1 stop6h 52m
Lambert-St Louis
Tue 5/14
1 stop25h 10m
$89
OntarioChicago Midway
ONT - MDW
ONTMDW
Ontario
Mon 5/13
1 stop19h 06m
Chicago Midway
Mon 5/20
1 stop13h 54m
$89
OntarioLambert-St Louis
ONT - STL
ONTSTL
Ontario
Thu 5/9
1 stop9h 20m
Lambert-St Louis
Sat 5/11
1 stop6h 20m
$90
OntarioChicago O'Hare Intl
ONT - ORD
ONTORD
Ontario
Mon 4/29
2 stops13h 14m
Chicago O'Hare Intl
Sat 5/4
1 stop7h 32m
$156
OntarioMoline Quad-City
ONT - MLI
ONTMLI
Ontario
Sat 6/8
1 stop8h 37m
Moline Quad-City
Fri 6/14
1 stop7h 25m
$264
No data available for this route at this time. Please check back soon.
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 April 18, 2024.
Get a feel of what it's like to fly with Alaska Airlines, American Airlines and Delta 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.
9,106 reviews
Comfort
7.9
Entertainment
7.3
Boarding
8.2
Food
7.3
Overall
8.1
Crew
8.6
Reviews
1 / 10
Paid a lot for our exit row seats and they weren’t that roomy.
9,106 reviews
9,106 reviews
Comfort
7.9
Entertainment
7.3
Boarding
8.2
Food
7.3
Overall
8.1
Crew
8.6
Reviews
1 / 10
Paid a lot for our exit row seats and they weren’t that roomy.
11,104 reviews
9,106 reviews
Comfort
7.9
Entertainment
7.3
Boarding
8.2
Food
7.3
Overall
8.1
Crew
8.6
Reviews
1 / 10
Paid a lot for our exit row seats and they weren’t that roomy.
3,977 reviews
9,106 reviews
Comfort
7.9
Entertainment
7.3
Boarding
8.2
Food
7.3
Overall
8.1
Crew
8.6
Reviews
1 / 10
Paid a lot for our exit row seats and they weren’t that roomy.
11,341 reviews
9,106 reviews
Comfort
7.9
Entertainment
7.3
Boarding
8.2
Food
7.3
Overall
8.1
Crew
8.6
Reviews
1 / 10
Paid a lot for our exit row seats and they weren’t that roomy.
14,963 reviews
9,106 reviews
Comfort
7.9
Entertainment
7.3
Boarding
8.2
Food
7.3
Overall
8.1
Crew
8.6
Reviews
1 / 10
Paid a lot for our exit row seats and they weren’t that roomy.
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.
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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
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 3,192,047 searches. Data last updated April 18, 2024.
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 April 18, 2024.
| 34%of flight departures | Early morningMidnight to 6 am |
|---|---|
| 66%of flight departures | Morning6 am to noon |
| 0%of flight departures | AfternoonNoon to 6 pm |
| 0%of flight departures | Evening6 pm to midnight |
Midnight
6 AM
Noon
6 PM
Book a flight to one of these trending destinations
User searches for flights to these destinations increased 20% or more in the past 90 days compared to other destinations
Fly with Cheapflights
Find the best flight deals on Cheapflights, where travelers can enjoy low prices and a wide availability of flights to their desired destinations.
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.