$89+ Cheap flights from Chicago (CHI) to Ontario (ONT)
This is the cheapest round-trip flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 11/7. Fares are subject to change and may not be available on all flights or dates of travel.
CHI — ONT
Oct 15 — Oct 221
Round-trip
1 adult, Economy
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Find cheap flights from Chicago to Ontario 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
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Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.Cheap flight deals from Chicago to Ontario
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Cheapest flights from Chicago to OntarioExplore the most affordable flight options available from Chicago to Ontario. Find the lowest fares from popular airlines and budget airlines, with prices last updated on September 15, 2026.
Explore the most affordable flight options available from Chicago to Ontario. Find the lowest fares from popular airlines and budget airlines, with prices last updated on September 15, 2026.
This Kiwi.com deal was found by Cheapflights users on 9/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 11/116:30 am -
1 stop19h 21m
Sat 11/1411:52 am -
1 stop10h 29m
Deal found 9/10![Frontier logo]()
$160
This deal was found by Cheapflights users on 9/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/206:30 am -
1 stop5h 59m
Sun 10/258:35 pm -
1 stop6h 41m
Deal found 9/13![Frontier logo]()
$163
This Kiwi.com deal was found by Cheapflights users on 9/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/206:30 am -
1 stop19h 20m
Tue 10/276:25 am -
1 stop15h 56m
Deal found 9/12![Frontier logo]()
$180
This Priceline deal was found by Cheapflights users on 9/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Priceline is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/246:30 am -
1 stop5h 59m
Sat 10/3111:52 am -
1 stop10h 29m
Deal found 9/10![Frontier logo]()
$195
This Southwest deal was found by Cheapflights users on 9/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/274:45 pm -
1 stop6h 05m
Sat 10/316:30 am -
Nonstop3h 50m
Deal found 9/15![Southwest logo]()
$195
This Expedia deal was found by Cheapflights users on 9/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/55:15 pm -
1 stop20h 01m
Wed 11/116:25 am -
1 stop15h 56m
Deal found 9/10![Frontier logo]()
$198
This Frontier deal was found by Cheapflights users on 9/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/66:30 am -
1 stop6h 00m
Tue 10/1311:52 am -
1 stop10h 32m
Deal found 9/10![Frontier logo]()
$200
This Booking.com deal was found by Cheapflights users on 9/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/216:30 am -
1 stop5h 59m
Thu 10/2211:52 am -
1 stop10h 32m
Deal found 9/11![Frontier logo]()
$201
This Southwest deal was found by Cheapflights users on 9/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/2810:15 am -
1 stop8h 05m
Sat 10/316:30 am -
Nonstop3h 50m
Deal found 9/14![Southwest logo]()
$201
This Booking.com deal was found by Cheapflights users on 9/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/66:30 am -
1 stop6h 00m
Tue 10/65:44 pm -
1 stop9h 54m
Deal found 9/11![Frontier logo]()
$203
This Southwest deal was found by Cheapflights users on 9/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/710:25 am -
Nonstop4h 20m
Mon 11/911:55 pm -
Nonstop3h 45m
Deal found 9/14![Southwest logo]()
$203
This Gotogate deal was found by Cheapflights users on 9/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Gotogate is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/226:30 am -
1 stop19h 20m
Mon 10/268:35 pm -
1 stop6h 41m
Deal found 9/10![Frontier logo]()
$206
Best flights from Chicago to OntarioDiscover carefully curated flight deals from Chicago to Ontario that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated September 15, 2026.
Discover carefully curated flight deals from Chicago to Ontario that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated September 15, 2026.
This Southwest deal was found by Cheapflights users on 9/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/2810:15 am -
1 stop8h 05m
Sat 10/316:30 am -
Nonstop3h 50m
Deal found 9/14![Southwest logo]()
$201
This Delta deal was found by Cheapflights users on 9/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 12/511:28 am -
1 stop10h 28m
Mon 12/711:08 pm -
1 stop9h 21m
Deal found 9/13![Delta logo]()
$317
This Alaska Airlines deal was found by Cheapflights users on 9/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/67:00 am -
1 stop8h 16m
Mon 10/196:02 am -
1 stop10h 18m
Deal found 9/12![Alaska Airlines logo]()
$317
This United Airlines deal was found by Cheapflights users on 9/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/198:20 pm -
Nonstop4h 29m
Fri 10/237:00 am -
Nonstop4h 10m
Deal found 9/13![United Airlines logo]()
$381
This Southwest deal was found by Cheapflights users on 9/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/305:40 am -
1 stop7h 45m
Sun 11/111:55 pm -
Nonstop3h 45m
Deal found 9/10![Southwest logo]()
$287
This Delta deal was found by Cheapflights users on 9/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/268:55 am -
2 stops11h 46m
Tue 9/2911:54 am -
1 stop10h 03m
Deal found 9/12![Delta logo]()
$322
This Southwest deal was found by Cheapflights users on 9/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/1611:55 am -
Nonstop4h 15m
Mon 10/1911:55 pm -
Nonstop3h 45m
Deal found 9/12![Southwest logo]()
$297
This Alaska Airlines deal was found by Cheapflights users on 9/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/97:16 pm -
1 stop17h 01m
Mon 10/127:25 am -
1 stop27h 53m
Deal found 9/12![Alaska Airlines logo]()
$368
This Southwest deal was found by Cheapflights users on 9/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/261:15 pm -
1 stop7h 10m
Tue 9/291:50 pm -
1 stop7h 05m
Deal found 9/12![Southwest logo]()
$317
This United Airlines deal was found by Cheapflights users on 9/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/212:35 pm -
1 stop7h 26m
Fri 9/254:03 pm -
1 stop6h 56m
Deal found 9/11![United Airlines logo]()
$390
This Southwest deal was found by Cheapflights users on 9/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 1/123:50 pm -
Nonstop4h 20m
Fri 1/155:20 am -
Nonstop3h 45m
Deal found 9/11![Southwest logo]()
$318
This United Airlines deal was found by Cheapflights users on 9/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/262:30 pm -
1 stop8h 28m
Tue 9/297:00 am -
Nonstop4h 10m
Deal found 9/12![United Airlines logo]()
$421
This United Airlines deal was found by Cheapflights users on 9/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/234:15 pm -
Nonstop4h 32m
Fri 11/277:00 am -
Nonstop3h 58m
Deal found 9/14![United Airlines logo]()
$437
This Delta deal was found by Cheapflights users on 9/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 9/209:46 am -
1 stop10h 30m
Fri 9/2510:00 pm -
2 stops10h 37m
Deal found 9/15![Delta logo]()
$503
This United Airlines deal was found by Cheapflights users on 9/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/228:20 pm -
Nonstop4h 29m
Wed 10/281:35 pm -
1 stop6h 54m
Deal found 9/11![United Airlines logo]()
$437
This KAYAK deal was found by Cheapflights users on 9/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure KAYAK is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/128:20 pm -
Nonstop4h 29m
Wed 10/141:52 pm -
1 stop7h 08m
Deal found 9/11![United Airlines logo]()
$454
This United Airlines deal was found by Cheapflights users on 9/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/102:30 pm -
1 stop7h 45m
Sun 11/157:00 am -
Nonstop3h 58m
Deal found 9/14![United Airlines logo]()
$457
This United Airlines deal was found by Cheapflights users on 9/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/54:15 pm -
Nonstop4h 32m
Tue 11/107:00 am -
Nonstop3h 58m
Deal found 9/14![United Airlines logo]()
$499
Last-minute flights from Chicago to OntarioDiscover last-minute flight deals from Chicago to Ontario. Data last updated September 15, 2026 and is based on user searches.
Discover last-minute flight deals from Chicago to Ontario. Data last updated September 15, 2026 and is based on user searches.
This CheapOair deal was found by Cheapflights users on 9/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/37:32 pm -
1 stop13h 32m
Tue 10/1311:52 am -
1 stop10h 32m
Deal found 9/10![Frontier logo]()
$210
This Booking.com deal was found by Cheapflights users on 9/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/66:30 am -
1 stop6h 00m
Tue 10/65:44 pm -
1 stop9h 54m
Deal found 9/11![Frontier logo]()
$203
This Frontier deal was found by Cheapflights users on 9/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/76:30 am -
1 stop6h 00m
Tue 10/1311:52 am -
1 stop10h 32m
Deal found 9/10![Frontier logo]()
$200
This Gotogate deal was found by Cheapflights users on 9/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Gotogate is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/76:30 am -
1 stop19h 17m
Sat 11/711:52 am -
1 stop10h 29m
Deal found 9/11![Frontier logo]()
$208
This Alaska Airlines deal was found by Cheapflights users on 9/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/147:00 am -
1 stop8h 16m
Wed 10/216:02 am -
1 stop8h 48m
Deal found 9/14![Alaska Airlines logo]()
$209
This deal was found by Cheapflights users on 9/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/206:30 am -
1 stop5h 59m
Sun 10/258:35 pm -
1 stop6h 41m
Deal found 9/13![Frontier logo]()
$163
This Kiwi.com deal was found by Cheapflights users on 9/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/206:30 am -
1 stop19h 20m
Tue 10/276:25 am -
1 stop15h 56m
Deal found 9/12![Frontier logo]()
$180
This Booking.com deal was found by Cheapflights users on 9/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/216:30 am -
1 stop5h 59m
Thu 10/2211:52 am -
1 stop10h 32m
Deal found 9/11![Frontier logo]()
$201
This Gotogate deal was found by Cheapflights users on 9/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Gotogate is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/226:30 am -
1 stop19h 20m
Mon 10/268:35 pm -
1 stop6h 41m
Deal found 9/10![Frontier logo]()
$206
This Priceline deal was found by Cheapflights users on 9/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Priceline is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/246:30 am -
1 stop5h 59m
Sat 10/3111:52 am -
1 stop10h 29m
Deal found 9/10![Frontier logo]()
$195
This Southwest deal was found by Cheapflights users on 9/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/274:45 pm -
1 stop6h 05m
Sat 10/316:30 am -
Nonstop3h 50m
Deal found 9/15![Southwest logo]()
$195
This Southwest deal was found by Cheapflights users on 9/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/2810:15 am -
1 stop8h 05m
Sat 10/316:30 am -
Nonstop3h 50m
Deal found 9/14![Southwest logo]()
$201
One-way flights from Chicago to OntarioSearch for one-way flight options from Chicago to Ontario. Find affordable one-way fares based on user searches. Data last updated September 15, 2026.
Search for one-way flight options from Chicago to Ontario. Find affordable one-way fares based on user searches. Data last updated September 15, 2026.
This Frontier deal was found by Cheapflights users on 9/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/76:30 am -
1 stop6h 12m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/15![Frontier logo]()
$89
This Super.com deal was found by Cheapflights users on 9/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/76:30 am -
1 stop6h 00m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/10![Frontier logo]()
$96
This Super.com deal was found by Cheapflights users on 9/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/66:30 am -
1 stop6h 00m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/11![Frontier logo]()
$97
This United Airlines deal was found by Cheapflights users on 9/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/198:20 pm -
Nonstop4h 29m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/14![United Airlines logo]()
$98
This Frontier deal was found by Cheapflights users on 9/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/1212:20 pm -
1 stop8h 48m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/10![Frontier logo]()
$100
This Southwest deal was found by Cheapflights users on 9/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/64:45 pm -
1 stop6h 05m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/14![Southwest logo]()
$101
This Frontier deal was found by Cheapflights users on 9/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 11/66:30 am -
1 stop6h 12m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/15![Frontier logo]()
$102
This Trip.com deal was found by Cheapflights users on 9/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/1912:20 pm -
1 stop8h 48m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/10![Frontier logo]()
$103
This Super.com deal was found by Cheapflights users on 9/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/12:46 pm -
1 stop29h 02m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/10![Frontier logo]()
$104
This Priceline deal was found by Cheapflights users on 9/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Priceline is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/249:00 am -
1 stop11h 00m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/15![Alaska Airlines logo]()
$105
This Southwest deal was found by Cheapflights users on 9/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/75:45 am -
1 stop6h 00m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/14![Southwest logo]()
$105
This Kiwi.com deal was found by Cheapflights users on 9/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/126:30 am -
1 stop6h 05m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/11![Frontier logo]()
$110
Find flight deals from Chicago to Ontario
Discover tips and strategies to find the most affordable flight options for your journey from Chicago (CHI) to Ontario (ONT). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated September 15, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $160 (Kiwi.com) |
One-way from | $89 (Frontier) |
Popular in | January |
Cheapest in | August |
Average price | $325 |
Good round-trip deal | $277 or less |
Good one-way deal | $119 or less |
Cheapflights Fare Finder
Customize your flight search to find flights from Chicago to Ontario 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 7,457,451 searches. Data last updated September 15, 2026.
Use the filters below to find and compare flights from Chicago to Ontario that are best for you.
Fly from
Fly to
Route
Depart
Return
Cheapest round-trip
ChicagoOntario
MDW Chicago Midway - ONT Ontario
MDWONT
Chicago Midway
Wed 10/28
12:49 pm-8:25 pm
1 stop9h 36m
Ontario
Wed 12/31
12:00 am-2:00 am
Nonstop0h 00m
$119
ChicagoOntario
ORD Chicago O'Hare Intl - ONT Ontario
ORDONT
Chicago O'Hare Intl
Tue 12/15
7:18 pm-11:58 pm
1 stop6h 40m
Ontario
Wed 12/31
12:00 am-2:00 am
Nonstop0h 00m
$119
ChicagoOntario
ORD Chicago O'Hare Intl - ONT Ontario
ORDONT
Chicago O'Hare Intl
Sat 12/12
9:59 am-4:28 pm
2 stops8h 29m
Ontario
Wed 12/31
12:00 am-2:00 am
Nonstop0h 00m
$124
ChicagoOntario
MDW Chicago Midway - ONT Ontario
MDWONT
Chicago Midway
Sat 12/12
5:05 am-11:20 am
1 stop8h 15m
Ontario
Wed 12/31
12:00 am-2:00 am
Nonstop0h 00m
$159
ChicagoOntario
MDW Chicago Midway - ONT Ontario
MDWONT
Chicago Midway
Wed 11/11
5:50 am-9:45 am
1 stop5h 55m
Ontario
Wed 12/31
12:00 am-2:00 am
Nonstop0h 00m
$159
ChicagoOntario
ORD Chicago O'Hare Intl - ONT Ontario
ORDONT
Chicago O'Hare Intl
Sun 1/31
5:30 am-11:27 am
1 stop7h 57m
Ontario
Wed 12/31
12:00 am-2:00 am
Nonstop0h 00m
$159
ChicagoOntario
ORD Chicago O'Hare Intl - ONT Ontario
ORDONT
Chicago O'Hare Intl
Tue 3/9
6:59 pm-11:48 pm
1 stop6h 49m
Ontario
Wed 12/31
12:00 am-2:00 am
Nonstop0h 00m
$159
ChicagoOntario
MDW Chicago Midway - ONT Ontario
MDWONT
Chicago Midway
Sat 11/14
1:31 pm-11:00 pm
2 stops11h 29m
Ontario
Wed 12/31
12:00 am-2:00 am
Nonstop0h 00m
$164
ChicagoOntario
MDW Chicago Midway - ONT Ontario
MDWONT
Chicago Midway
Wed 3/10
9:55 am-10:43 pm
2 stops14h 48m
Ontario
Wed 12/31
12:00 am-2:00 am
Nonstop0h 00m
$164
ChicagoOntario
MDW Chicago Midway - ONT Ontario
MDWONT
Chicago Midway
Wed 12/9
12:39 pm-11:58 pm
2 stops13h 19m
Ontario
Wed 12/31
12:00 am-2:00 am
Nonstop0h 00m
$164
Showing 1-10 of 40 resultsSorted by cheapest first
Compare providers for flights from Chicago to Ontario
Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Chicago to Ontario in September.
| Provider | Price Accuracy | Trust Score* |
|---|---|---|
| Price Accuracy1 star | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy- | Trust Score*1 star |
- Most accurate provider: When it comes to deals on Chicago-Ontario flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Chicago-Ontario flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Chicago-Ontario flight searches over the past month and is updated monthly.
- Most trusted provider: When it comes to deals on Chicago-Ontario 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 Chicago-Ontario 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 Chicago to Ontario
Have a flexible travel schedule? Discover the best time to fly to Ontario from Chicago with our price prediction graph.
CHI-ONT
ORD-ONT
MDW-ONT
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.
Cheapflights Insights
Everything you need to know about your flight from Chicago to Ontario
CHI-ONT
ORD-ONT
MDW-ONT
What is the cheapest month to book a flight from Chicago to Ontario?
Currently, October is the cheapest month in which you can book a flight from Chicago to Ontario (average of $346). Flying from Chicago to Ontario in December is currently the most expensive (average of $582). 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 CHI to ONT?
Find hourly flight availability from Chicago to Ontario. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated September 15, 2026.
Unlike in the evening, when flights are generally more expensive, you can save up to 66% on flights from Chicago to Ontario by exploring options for tickets at noon.
How much does it cost to fly round-trip from Chicago to Ontario?
Airfare is below average for this route at the moment.
Chicago to Ontario flights typically cost between $290 and $418 in November.The cheapest round-trip price found within the last 5 days was $160 on Frontier (Nov 11-Nov 14).
What’s the top layover airport for flights from Chicago to Ontario?
Share of 1-stop round-trip flights from Chicago to Ontario chosen by Cheapflights users in the past 12 months, using the same layover each way.
Phoenix (PHX) – chosen by Cheapflights users on 67% of 1-stop itineraries from Chicago to Ontario on Cheapflights.
What’s the cheapest layover airport for flights from Chicago to Ontario?
Average round-trip fare for 1-stop flights from Chicago to Ontario, chosen by Cheapflights users in the past 12 months, with the same layover each way.
Phoenix (PHX) is the most affordable 1-stop option, with an average round-trip price of $312.
What’s the fastest layover option from Chicago to Ontario?
Shortest average travel time for 1-stop one-way flights from Chicago to Ontario, based on itineraries clicked by Cheapflights users over the past 12 months, grouped by layover airport.
Flights via Denver (DEN) have the shortest average one-way travel time for 1-stop routes: 5h 30m.
Which airport typically offers the quickest layover for flights from Chicago to Ontario?
Average layover duration for 1-stop one-way flights from Chicago to Ontario, chosen by Cheapflights users in the last 12 months, grouped by stopover airport.
Flights via Denver (DEN) offer the fastest connection on this route, with an average layover time of 0h 55m.
The best insider tips for Chicago to Ontario flights
AI-powered summary based on content written by travel experts. AI can make mistakes.
Cheapflights partnered with top experts to bring you the best recommendations for your Chicago to Ontario trip
Our travel experts
Reviews of airlines servicing Ontario
Get insights into the airlines that provide service to Ontario. 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 Ontario. Reviews last updated September 15, 2026.
Read through reviews of airlines operating flights from Chicago to Ontario, such as Southwest,United Airlines, andFrontier. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Comfort
8.0
Entertainment
7.5
Food
7.0
Crew
8.6
Overall
8.0
Boarding
8.1
Reviews
1 / 20
10.0
ExcellentWalter,May 2026
LAS - BUR
Comfort
8.0
Entertainment
7.5
Food
7.0
Crew
8.6
Overall
8.0
Boarding
8.1
Reviews
1 / 20
10.0
ExcellentWalter,May 2026
LAS - BUR
Comfort
8.0
Entertainment
7.5
Food
7.0
Crew
8.6
Overall
8.0
Boarding
8.1
Reviews
1 / 20
10.0
ExcellentWalter,May 2026
LAS - BUR
Comfort
8.0
Entertainment
7.5
Food
7.0
Crew
8.6
Overall
8.0
Boarding
8.1
Reviews
1 / 20
10.0
ExcellentWalter,May 2026
LAS - BUR
Related info for your journey
Find useful and relevant information for your journey from Chicago to Ontario. 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 Chicago to Ontario
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Complete your trip
Complete your trip to Ontario by adding a car rental and/or hotel reservation to your travel itinerary.
Search flights from Chicago to Ontario by cabin class
Find flights from Chicago to Ontario, based on your preferred cabin class, be it economy, premium economy, business, or first class.
Other flights to Ontario
Explore flights to Ontario departing from other origins. Flights are based on user searches made on Cheapflights and were last updated on September 15, 2026.
Chicago and Ontario flights
Browse other Chicago and Ontario flight options. Last updated on September 15, 2026.
Other flights from Chicago
Browse through other flights departing from Chicago. Flights are based on user searches made on Cheapflights and were last updated on September 15, 2026.
Popular flight searches
Check out other popular destinations found by fellow travelers in 2026
Top 5 airlines flying from Chicago to Ontario
Discover the top 5 airlines that operate flights from Chicago to Ontario. 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 7,457,451 searches. Data last updated September 15, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$167 | Average$270 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$236 | Average$377 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$268 | Average$456 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$276 | Average$472 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$293 | Average$524 | FlexibilityNo cancel fee | On-time71% |