$108+ Cheap flights from Ontario (ONT) to Chicago (CHI)
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 1/5. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — CHI
Dec 3 — Dec 101
Round-trip
1 adult, Economy
We work with more than 300 partners to bring you better travel deals
Find cheap flights from Ontario to Chicago 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
We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.3. Compare prices and book
Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.Cheapflights Tip: The best prices from Ontario to Chicago are usually found in January or September, booked 85 days in advance, depart on a Saturday or Wednesday and return on a Thursday
Cheap flight deals from Ontario to Chicago
Cheapest
Best
Last-minute
One-way
Cheapest flights from Ontario to ChicagoExplore the most affordable flight options available from Ontario to Chicago. Find the lowest fares from popular airlines and budget airlines, with prices last updated on November 3, 2026.
Explore the most affordable flight options available from Ontario to Chicago. Find the lowest fares from popular airlines and budget airlines, with prices last updated on November 3, 2026.
This Southwest deal was found by Cheapflights users on 11/1. 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.
Thu 11/2611:25 am -
1 stop5h 25m
Sat 12/56:05 am -
2 stops8h 45m
Deal found 11/1![Southwest logo]()
$264
This Booking.com deal was found by Cheapflights users on 10/29. 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.
Thu 10/298:03 pm -
1 stop11h 32m
Sun 11/16:30 am -
1 stop6h 05m
Deal found 10/29![Frontier logo]()
$264
This Kiwi.com deal was found by Cheapflights users on 10/29. 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 11/198:35 pm -
1 stop6h 38m
Sat 11/216:40 am -
2 stops25h 40m
Deal found 10/29![Frontier logo]()
$265
This Mytrip deal was found by Cheapflights users on 10/29. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/176:30 am -
2 stops14h 19m
Wed 12/237:35 am -
1 stop16h 18m
Deal found 10/29![Frontier logo]()
$266
This Cheapflightsfares deal was found by Cheapflights users on 10/31. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 11/256:45 am -
1 stop16h 08m
Sat 11/285:15 am -
1 stop29h 15m
Deal found 10/31![Frontier logo]()
$267
This Southwest deal was found by Cheapflights users on 10/29. 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 12/98:40 am -
2 stops9h 10m
Sun 12/1312:45 pm -
2 stops9h 05m
Deal found 10/29![Southwest logo]()
$268
This CheapOair deal was found by Cheapflights users on 10/30. 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.
Tue 12/228:56 am -
1 stop18h 53m
Tue 12/297:35 am -
1 stop25h 32m
Deal found 10/30![Frontier logo]()
$268
This Delta deal was found by Cheapflights users on 11/2. 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.
Tue 12/86:00 am -
2 stops10h 26m
Wed 12/912:34 pm -
2 stops13h 23m
Deal found 11/2![Delta logo]()
$269
This Southwest deal was found by Cheapflights users on 11/1. 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 12/16:25 pm -
1 stop9h 20m
Sat 12/56:05 am -
2 stops8h 20m
Deal found 11/1![Southwest logo]()
$270
This CheapOair deal was found by Cheapflights users on 10/29. 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.
Thu 11/128:35 pm -
1 stop6h 38m
Sat 11/215:15 am -
1 stop9h 27m
Deal found 10/29![Frontier logo]()
$270
This Mytrip deal was found by Cheapflights users on 11/2. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/22:00 pm -
2 stops24h 07m
Sat 12/510:40 am -
2 stops27h 11m
Deal found 11/2![Frontier logo]()
$272
This United Airlines deal was found by Cheapflights users on 11/1. 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 12/57:00 am -
Nonstop4h 11m
Tue 12/84:15 pm -
Nonstop4h 29m
Deal found 11/1![United Airlines logo]()
$272
Best flights from Ontario to ChicagoDiscover carefully curated flight deals from Ontario to Chicago that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated November 3, 2026.
Discover carefully curated flight deals from Ontario to Chicago that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated November 3, 2026.
This Southwest deal was found by Cheapflights users on 10/29. 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 2/1912:00 pm -
1 stop8h 20m
Tue 2/2310:20 am -
2 stops10h 15m
Deal found 10/29![Southwest logo]()
$264
This Delta deal was found by Cheapflights users on 10/31. 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 12/131:11 pm -
1 stop6h 45m
Thu 12/177:18 pm -
1 stop6h 39m
Deal found 10/31![Delta logo]()
$318
This United Airlines deal was found by Cheapflights users on 10/30. 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 3/66:30 am -
Nonstop4h 08m
Mon 3/87:45 pm -
Nonstop4h 30m
Deal found 10/30![United Airlines logo]()
$338
This Southwest deal was found by Cheapflights users on 10/30. 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.
Thu 11/266:40 am -
Nonstop3h 45m
Fri 12/43:55 pm -
Nonstop4h 20m
Deal found 10/30![Southwest logo]()
$289
This Southwest deal was found by Cheapflights users on 11/2. 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 12/16:25 pm -
1 stop9h 20m
Sat 12/510:25 am -
Nonstop4h 20m
Deal found 11/2![Southwest logo]()
$294
This Delta deal was found by Cheapflights users on 10/30. 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.
Mon 11/1611:10 pm -
2 stops12h 49m
Sun 11/227:17 pm -
1 stop6h 32m
Deal found 10/30![Delta logo]()
$342
This United Airlines deal was found by Cheapflights users on 11/1. 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.
Fri 1/111:52 pm -
Nonstop3h 54m
Tue 1/52:24 pm -
1 stop8h 36m
Deal found 11/1![United Airlines logo]()
$344
This Southwest deal was found by Cheapflights users on 11/2. 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 2/58:00 am -
2 stops8h 00m
Mon 2/83:55 pm -
2 stops8h 30m
Deal found 11/2![Southwest logo]()
$319
This Delta deal was found by Cheapflights users on 11/2. 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.
Thu 11/195:56 pm -
2 stops13h 08m
Mon 11/236:23 am -
2 stops12h 53m
Deal found 11/2![Delta logo]()
$368
This United Airlines deal was found by Cheapflights users on 10/30. 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 12/11:40 pm -
1 stop8h 19m
Sat 12/54:15 pm -
Nonstop4h 29m
Deal found 10/30![United Airlines logo]()
$369
This Southwest deal was found by Cheapflights users on 10/29. 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.
Thu 2/188:30 am -
2 stops7h 30m
Tue 2/2310:20 am -
2 stops10h 15m
Deal found 10/29![Southwest logo]()
$319
This United Airlines deal was found by Cheapflights users on 11/1. 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 12/177:00 am -
Nonstop4h 00m
Thu 12/317:37 am -
1 stop9h 42m
Deal found 11/1![United Airlines logo]()
$376
This Southwest deal was found by Cheapflights users on 11/1. 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 12/186:20 am -
2 stops7h 20m
Mon 1/45:20 pm -
2 stops7h 30m
Deal found 11/1![Southwest logo]()
$349
This United Airlines deal was found by Cheapflights users on 10/29. 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.
Fri 12/47:00 am -
Nonstop4h 11m
Sun 12/67:00 am -
1 stop7h 34m
Deal found 10/29![United Airlines logo]()
$388
This Delta deal was found by Cheapflights users on 11/2. 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.
Tue 11/241:15 pm -
1 stop6h 32m
Fri 11/277:30 am -
1 stop6h 50m
Deal found 11/2![Delta logo]()
$439
This Southwest deal was found by Cheapflights users on 10/29. 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 11/1810:55 am -
Nonstop3h 50m
Sat 11/214:50 pm -
1 stop7h 35m
Deal found 10/29![Southwest logo]()
$358
This United Airlines deal was found by Cheapflights users on 11/1. 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 1/307:00 am -
Nonstop4h 00m
Sun 2/74:10 pm -
Nonstop4h 40m
Deal found 11/1![United Airlines logo]()
$398
This Delta deal was found by Cheapflights users on 10/29. 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.
Fri 11/205:56 pm -
2 stops13h 08m
Sun 11/226:23 am -
2 stops12h 53m
Deal found 10/29![Delta logo]()
$458
This Southwest deal was found by Cheapflights users on 10/30. 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.
Mon 11/309:40 pm -
1 stop6h 05m
Wed 12/25:20 am -
1 stop6h 00m
Deal found 10/30![Southwest logo]()
$418
This Southwest deal was found by Cheapflights users on 10/30. 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 11/146:00 am -
2 stops9h 25m
Wed 11/183:55 pm -
Nonstop4h 20m
Deal found 10/30![Southwest logo]()
$452
This Southwest deal was found by Cheapflights users on 10/31. 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 11/1810:05 am -
1 stop5h 20m
Tue 11/245:00 am -
1 stop8h 50m
Deal found 10/31![Southwest logo]()
$458
Last-minute flights from Ontario to ChicagoDiscover last-minute flight deals from Ontario to Chicago. Data last updated November 3, 2026 and is based on user searches.
Discover last-minute flight deals from Ontario to Chicago. Data last updated November 3, 2026 and is based on user searches.
This Mytrip deal was found by Cheapflights users on 10/31. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/244:13 pm -
2 stops16h 47m
Thu 12/108:53 pm -
1 stop12h 51m
Deal found 10/31![Frontier logo]()
$273
This Cheapflightsfares deal was found by Cheapflights users on 10/31. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 11/256:45 am -
1 stop16h 08m
Sat 11/285:15 am -
1 stop29h 15m
Deal found 10/31![Frontier logo]()
$267
This Southwest deal was found by Cheapflights users on 11/2. 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.
Thu 11/265:50 am -
2 stops7h 00m
Fri 12/43:50 pm -
1 stop7h 15m
Deal found 11/2![Southwest logo]()
$264
This CheapOair deal was found by Cheapflights users on 10/31. 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.
Thu 11/266:08 pm -
1 stop11h 38m
Mon 11/305:15 am -
1 stop16h 21m
Deal found 10/31![Frontier logo]()
$265
This Southwest deal was found by Cheapflights users on 11/1. 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.
Thu 11/266:40 am -
Nonstop3h 45m
Sat 12/510:25 am -
Nonstop4h 20m
Deal found 11/1![Southwest logo]()
$269
This Delta deal was found by Cheapflights users on 11/2. 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.
Thu 11/267:05 am -
2 stops10h 34m
Fri 12/412:34 pm -
2 stops12h 25m
Deal found 11/2![Delta logo]()
$269
This Mytrip deal was found by Cheapflights users on 11/2. 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 Mytrip is selected, and click “Compare selected ” under the list of providers to see comparable flight deals.
Thu 11/2611:40 am -
2 stops18h 06m
Fri 12/48:59 am -
2 stops17h 18m
Deal found 11/2![Frontier logo]()
$274
This Mytrip deal was found by Cheapflights users on 10/31. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/306:45 am -
1 stop16h 08m
Mon 12/76:21 am -
2 stops19h 02m
Deal found 10/31![Frontier logo]()
$264
This United Airlines deal was found by Cheapflights users on 11/1. 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 12/57:00 am -
Nonstop4h 11m
Tue 12/84:15 pm -
Nonstop4h 29m
Deal found 11/1![United Airlines logo]()
$272
This CheapOair deal was found by Cheapflights users on 10/30. 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.
Thu 12/1011:30 am -
1 stop11h 24m
Tue 12/297:35 am -
1 stop25h 32m
Deal found 10/30![Frontier logo]()
$270
This Mytrip deal was found by Cheapflights users on 10/29. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/176:30 am -
2 stops14h 19m
Wed 12/237:35 am -
1 stop16h 18m
Deal found 10/29![Frontier logo]()
$266
This CheapOair deal was found by Cheapflights users on 10/29. 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.
Tue 12/228:56 am -
1 stop18h 53m
Tue 12/297:35 am -
1 stop25h 32m
Deal found 10/29![Frontier logo]()
$268
One-way flights from Ontario to ChicagoSearch for one-way flight options from Ontario to Chicago. Find affordable one-way fares based on user searches. Data last updated November 3, 2026.
Search for one-way flight options from Ontario to Chicago. Find affordable one-way fares based on user searches. Data last updated November 3, 2026.
This Kiwi.com deal was found by Cheapflights users on 10/29. 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 1/52:12 pm -
2 stops16h 44m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 10/29![Frontier logo]()
$108
This Super.com deal was found by Cheapflights users on 11/1. 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 12/236:30 am -
1 stop15h 56m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 11/1![Frontier logo]()
$108
This Kiwi.com deal was found by Cheapflights users on 10/30. 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 1/59:00 am -
2 stops24h 55m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 10/30![Frontier logo]()
$110
This Super.com deal was found by Cheapflights users on 11/2. 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 11/242:01 pm -
1 stop13h 09m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 11/2![Frontier logo]()
$111
This Cheapflightsfares deal was found by Cheapflights users on 11/1. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 2/76:27 pm -
1 stop9h 43m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 11/1![Frontier logo]()
$112
This Trip.com deal was found by Cheapflights users on 10/30. 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.
Fri 11/202:01 pm -
1 stop13h 09m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 10/30![Frontier logo]()
$113
This Southwest deal was found by Cheapflights users on 10/29. 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.
Thu 11/265:50 am -
2 stops7h 00m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 10/29![Southwest logo]()
$114
This iWofly deal was found by Cheapflights users on 11/1. 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 iWofly is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 1/1712:15 pm -
1 stop15h 55m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 11/1![Frontier logo]()
$115
This Kiwi.com deal was found by Cheapflights users on 10/29. 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 1/268:02 am -
2 stops26h 11m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 10/29![Frontier logo]()
$116
This CheapOair deal was found by Cheapflights users on 11/2. 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.
Fri 1/16:30 am -
1 stop15h 56m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 11/2![Frontier logo]()
$116
This Super.com deal was found by Cheapflights users on 11/2. 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 11/198:35 pm -
1 stop6h 38m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 11/2![Frontier logo]()
$117
This Delta deal was found by Cheapflights users on 10/29. 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.
Thu 11/2612:18 pm -
1 stop8h 36m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 10/29![Delta logo]()
$119
Find flight deals from Ontario to Chicago
Discover tips and strategies to find the most affordable flight options for your journey from Ontario (ONT) to Chicago (CHI). 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 November 3, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $264 (Southwest) |
One-way from | $108 (Kiwi.com) |
Popular in | June |
Cheapest in | January |
Average price | $437 |
Good round-trip deal | $377 or less |
Good one-way deal | $169 or less |
Cheapflights Fare Finder
Customize your flight search to find flights from Ontario to Chicago 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 November 3, 2026.
Use the filters below to find and compare flights from Ontario to Chicago that are best for you.
Fly from
Fly to
Route
Depart
Return
Cheapest round-trip
OntarioChicago
ONT Ontario - MDW Chicago Midway
ONTMDW
Ontario
Tue 12/15
6:00 am-4:50 pm
2 stops8h 50m
Chicago Midway
Wed 12/31
12:00 am-10:00 pm
Nonstop0h 00m
$124
OntarioChicago
ONT Ontario - MDW Chicago Midway
ONTMDW
Ontario
Tue 1/26
11:15 am-7:25 pm
1 stop6h 10m
Chicago Midway
Wed 12/31
12:00 am-10:00 pm
Nonstop0h 00m
$130
OntarioChicago
ONT Ontario - MDW Chicago Midway
ONTMDW
Ontario
Wed 1/13
1:07 pm-10:17 pm
1 stop7h 10m
Chicago Midway
Wed 12/31
12:00 am-10:00 pm
Nonstop0h 00m
$130
OntarioChicago
ONT Ontario - MDW Chicago Midway
ONTMDW
Ontario
Wed 12/16
8:40 am-7:50 pm
2 stops9h 10m
Chicago Midway
Wed 12/31
12:00 am-10:00 pm
Nonstop0h 00m
$135
OntarioChicago
ONT Ontario - ORD Chicago O'Hare Intl
ONTORD
Ontario
Tue 12/15
6:00 am-4:43 pm
2 stops8h 43m
Chicago O'Hare Intl
Wed 12/31
12:00 am-10:00 pm
Nonstop0h 00m
$135
OntarioChicago
ONT Ontario - ORD Chicago O'Hare Intl
ONTORD
Ontario
Wed 12/23
10:35 pm-12:46 pm
2 stops12h 11m
Chicago O'Hare Intl
Wed 12/31
12:00 am-10:00 pm
Nonstop0h 00m
$135
OntarioChicago
ONT Ontario - ORD Chicago O'Hare Intl
ONTORD
Ontario
Thu 12/17
1:11 pm-9:56 pm
1 stop6h 45m
Chicago O'Hare Intl
Wed 12/31
12:00 am-10:00 pm
Nonstop0h 00m
$160
OntarioChicago
ONT Ontario - MDW Chicago Midway
ONTMDW
Ontario
Sun 2/7
8:50 pm-5:45 am
1 stop6h 55m
Chicago Midway
Wed 12/31
12:00 am-10:00 pm
Nonstop0h 00m
$169
OntarioChicago
ONT Ontario - MDW Chicago Midway
ONTMDW
Ontario
Fri 11/13
11:10 pm-10:24 am
1 stop9h 14m
Chicago Midway
Wed 12/31
12:00 am-10:00 pm
Nonstop0h 00m
$169
OntarioChicago
ONT Ontario - MDW Chicago Midway
ONTMDW
Ontario
Sat 4/17
12:00 pm-10:10 pm
1 stop8h 10m
Chicago Midway
Wed 12/31
12:00 am-10:00 pm
Nonstop0h 00m
$169
Showing 1-10 of 40 resultsSorted by cheapest first
Compare providers for flights from Ontario to Chicago
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 Ontario to Chicago in November.
| Provider | Price Accuracy | Trust Score* |
|---|---|---|
| Price Accuracy1 star | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy2 stars | Trust Score*3 stars | |
| Price Accuracy- | Trust Score*1 star |
- Most accurate provider: When it comes to deals on Ontario-Chicago flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Ontario-Chicago flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Ontario-Chicago flight searches over the past month and is updated monthly.
- Most trusted provider: When it comes to deals on Ontario-Chicago 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 Ontario-Chicago 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 Ontario to Chicago
Have a flexible travel schedule? Discover the best time to fly to Chicago from Ontario with our price prediction graph.
ONT-CHI
ONT-MDW
ONT-ORD
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 Ontario to Chicago
ONT-CHI
ONT-MDW
ONT-ORD
What is the cheapest month to book a flight from Ontario to Chicago?
Currently, January is the cheapest month in which you can book a flight from Ontario to Chicago (average of $320). Flying from Ontario to Chicago in July is currently the most expensive (average of $481). 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 ONT to CHI?
Find hourly flight availability from Ontario to Chicago. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated November 3, 2026.
When flying from Ontario to Chicago, the time of day you decide to fly out makes little to no difference towards the overall price you’ll pay on tickets.
How much does it cost to fly round-trip from Ontario to Chicago?
Airfare is below average for this route at the moment.
Ontario to Chicago flights typically cost between $336 and $550 in November.The cheapest round-trip price found within the last 5 days was $264 on Southwest (Nov 26-Dec 4).
How far ahead should I book a flight from Ontario to Chicago?
The best time to book flights from Ontario to Chicago is 82 days before your desired departure date. The cost of your flight will likely increase significantly if you book two weeks in advance of your flight.
The best insider tips for Ontario to Chicago 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 Ontario to Chicago trip
Our travel experts
Reviews of airlines servicing Chicago
Get insights into the airlines that provide service to Chicago. 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 Chicago. Reviews last updated November 3, 2026.
See what other customers who have flown with Southwest,Delta, andUnited Airlines from Ontario to Chicago have to say. You can also see how each airline compares in terms of entertainment options, comfort, food, crew/service, and boarding process.
Overall
8.0
Boarding
8.1
Crew
8.6
Food
7.0
Comfort
8.0
Entertainment
7.5
Reviews
1 / 20
6.0
GoodReza,Jun 2026
TPA - MDW
Overall
8.0
Boarding
8.1
Crew
8.6
Food
7.0
Comfort
8.0
Entertainment
7.5
Reviews
1 / 20
6.0
GoodReza,Jun 2026
TPA - MDW
Overall
8.0
Boarding
8.1
Crew
8.6
Food
7.0
Comfort
8.0
Entertainment
7.5
Reviews
1 / 20
6.0
GoodReza,Jun 2026
TPA - MDW
Overall
8.0
Boarding
8.1
Crew
8.6
Food
7.0
Comfort
8.0
Entertainment
7.5
Reviews
1 / 20
6.0
GoodReza,Jun 2026
TPA - MDW
Overall
8.0
Boarding
8.1
Crew
8.6
Food
7.0
Comfort
8.0
Entertainment
7.5
Reviews
1 / 20
6.0
GoodReza,Jun 2026
TPA - MDW
Overall
8.0
Boarding
8.1
Crew
8.6
Food
7.0
Comfort
8.0
Entertainment
7.5
Reviews
1 / 20
6.0
GoodReza,Jun 2026
TPA - MDW
Related info for your journey
Find useful and relevant information for your journey from Ontario to Chicago. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.
Traveling to a place near Chicago?
Book flights to Chicago if you plan to visit one of these locationsBenton Harbor
Merrillville
Lansing
Valparaiso
Hammond
Saint Joseph
Porter
Browse thousands of different options on Cheapflights for your next trip
Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.
Alternative routes
Chicago flight routes
Complete your trip
Flights by cabin class
Other flight options
Other flights from Ontario
Popular flights
Alternative routes for Ontario to Chicago
See prices for flight routes from nearby airports that may be better suited for you.
Other flights to Chicago
Explore flights to Chicago departing from other origins. Flights are based on user searches made on Cheapflights and were last updated on November 3, 2026.
Complete your trip
Complete your trip to Chicago by adding a car rental and/or hotel reservation to your travel itinerary.
Search flights from Ontario to Chicago by cabin class
Find flights from Ontario to Chicago, based on your preferred cabin class, be it economy, premium economy, business, or first class.
Ontario and Chicago flights
Browse other Ontario and Chicago flight options. Last updated on November 3, 2026.
Other flights from Ontario
Browse through other flights departing from Ontario. Flights are based on user searches made on Cheapflights and were last updated on November 3, 2026.
Popular flight searches
Check out other popular destinations found by fellow travelers in 2026
Top 5 airlines flying from Ontario to Chicago
Discover the top 5 airlines that operate flights from Ontario to Chicago. 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 November 3, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$118 | Average$336 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$160 | Average$260 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$253 | Average$498 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$272 | Average$446 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$276 | Average$406 | FlexibilityNo cancel fee | On-time71% |