$118+ Cheap flights from Illinois 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 11/6. Fares are subject to change and may not be available on all flights or dates of travel.
ORD — ONT
Nov 6 — Nov 131
Round-trip
1 adult, Economy
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Find cheap flights from Illinois 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 Illinois to Ontario
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Cheapest flights from Illinois to OntarioExplore the most affordable flight options available from Illinois to Ontario. Find the lowest fares from popular airlines and budget airlines, with prices last updated on October 7, 2026.
Explore the most affordable flight options available from Illinois to Ontario. Find the lowest fares from popular airlines and budget airlines, with prices last updated on October 7, 2026.
This Frontier deal was found by Cheapflights users on 10/5. 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
Thu 11/122:23 pm -
1 stop12h 50m
Deal found 10/5![Frontier logo]()
$178
This Frontier deal was found by Cheapflights users on 10/5. 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 11/56:30 am -
1 stop6h 05m
Wed 11/1111:52 am -
1 stop10h 29m
Deal found 10/5![Frontier logo]()
$179
This CheapOair deal was found by Cheapflights users on 10/5. 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 11/108:59 am -
1 stop9h 39m
Mon 11/168:35 pm -
1 stop6h 38m
Deal found 10/5![Frontier logo]()
$183
This FlightHub deal was found by Cheapflights users on 10/5. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/206:30 am -
1 stop5h 59m
Sat 10/2411:52 am -
1 stop10h 32m
Deal found 10/5![Frontier logo]()
$187
This CheapOair deal was found by Cheapflights users on 10/5. 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 11/1410:29 am -
1 stop8h 09m
Tue 11/176:30 am -
1 stop15h 51m
Deal found 10/5![Frontier logo]()
$188
This Cheapflightsfares deal was found by Cheapflights users on 10/5. 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.
Thu 11/510:29 am -
1 stop10h 39m
Fri 11/68:35 pm -
1 stop6h 38m
Deal found 10/5![Frontier logo]()
$189
This CheapOair deal was found by Cheapflights users on 10/5. 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.
Wed 10/146:30 am -
1 stop5h 59m
Wed 10/2111:52 am -
1 stop10h 32m
Deal found 10/5![Frontier logo]()
$190
This Frontier deal was found by Cheapflights users on 10/5. 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 11/1111:52 am -
1 stop10h 29m
Deal found 10/5![Frontier logo]()
$191
This Frontier deal was found by Cheapflights users on 10/5. 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 10/208:30 am -
1 stop10h 18m
Fri 10/2311:52 am -
1 stop10h 32m
Deal found 10/5![Frontier logo]()
$192
This CheapOair deal was found by Cheapflights users on 10/5. 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.
Mon 10/263:30 pm -
1 stop26h 51m
Mon 11/26:30 am -
1 stop15h 51m
Deal found 10/5![Frontier logo]()
$195
This Cheapflightsfares deal was found by Cheapflights users on 10/5. 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 11/46:30 am -
1 stop6h 05m
Thu 11/122:23 pm -
1 stop12h 50m
Deal found 10/5![Frontier logo]()
$198
This Frontier deal was found by Cheapflights users on 10/6. 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 11/265:25 am -
1 stop13h 58m
Sat 12/52:41 pm -
1 stop12h 20m
Deal found 10/6![Frontier logo]()
$200
Best flights from Illinois to OntarioDiscover carefully curated flight deals from Illinois to Ontario that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated October 7, 2026.
Discover carefully curated flight deals from Illinois to Ontario that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated October 7, 2026.
This Southwest deal was found by Cheapflights users on 10/7. 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 2/2410:15 am -
1 stop8h 05m
Mon 3/15:20 am -
Nonstop3h 45m
Deal found 10/7![Southwest logo]()
$307
This Delta deal was found by Cheapflights users on 10/7. 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.
Wed 10/287:35 am -
2 stops11h 37m
Sat 11/76:00 am -
2 stops8h 26m
Deal found 10/7![Delta logo]()
$315
This KAYAK deal was found by Cheapflights users on 10/4. 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.
Thu 10/225:10 pm -
1 stop7h 43m
Sun 10/257:34 pm -
1 stop8h 25m
Deal found 10/4![American Airlines logo]()
$437
This United Airlines deal was found by Cheapflights users on 10/7. 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 12/56:42 am -
2 stops7h 52m
Tue 12/811:20 am -
2 stops9h 39m
Deal found 10/7![United Airlines logo]()
$491
This Delta deal was found by Cheapflights users on 10/5. 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 11/311:39 am -
2 stops12h 32m
Tue 11/1012:18 pm -
1 stop8h 36m
Deal found 10/5![Delta logo]()
$322
This Delta deal was found by Cheapflights users on 10/4. 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 12/412:39 pm -
2 stops13h 18m
Mon 12/711:08 pm -
1 stop9h 20m
Deal found 10/4![Delta logo]()
$322
This Southwest deal was found by Cheapflights users on 10/6. 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 2/259:45 pm -
Nonstop4h 20m
Sun 2/285:25 am -
Nonstop3h 45m
Deal found 10/6![Southwest logo]()
$391
This Delta deal was found by Cheapflights users on 10/7. 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 12/511:08 am -
1 stop10h 47m
Tue 12/812:20 pm -
1 stop8h 41m
Deal found 10/7![Delta logo]()
$361
This Southwest deal was found by Cheapflights users on 10/5. 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 12/185:00 am -
1 stop8h 50m
Mon 12/2111:55 pm -
Nonstop3h 45m
Deal found 10/5![Southwest logo]()
$398
This Southwest deal was found by Cheapflights users on 10/6. 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 12/108:05 am -
1 stop8h 35m
Sun 12/1311:55 pm -
Nonstop3h 45m
Deal found 10/6![Southwest logo]()
$401
This KAYAK deal was found by Cheapflights users on 10/2. 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 KAYAK is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/207:35 am -
1 stop7h 01m
Thu 10/2211:56 am -
1 stop9h 38m
Deal found 10/2![Delta logo]()
$367
This United Airlines deal was found by Cheapflights users on 10/4. 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 12/55:00 am -
2 stops9h 34m
Wed 12/911:20 am -
2 stops9h 39m
Deal found 10/4![United Airlines logo]()
$491
This KAYAK deal was found by Cheapflights users on 10/6. 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.
Wed 10/146:55 am -
1 stop8h 35m
Fri 10/161:05 pm -
1 stop8h 25m
Deal found 10/6![American Airlines logo]()
$508
This Southwest deal was found by Cheapflights users on 10/2. 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.
Mon 11/235:55 am -
1 stop6h 00m
Thu 11/265:50 am -
1 stop7h 15m
Deal found 10/2![Southwest logo]()
$409
This United Airlines deal was found by Cheapflights users on 10/5. 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.
Wed 10/284:15 pm -
Nonstop4h 32m
Sun 11/16:57 am -
Nonstop4h 02m
Deal found 10/5![United Airlines logo]()
$497
This United Airlines deal was found by Cheapflights users on 10/4. 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.
Wed 1/278:40 am -
1 stop6h 00m
Sat 1/307:00 am -
1 stop7h 59m
Deal found 10/4![United Airlines logo]()
$499
This Delta deal was found by Cheapflights users on 10/6. 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.
Wed 12/162:04 pm -
2 stops10h 55m
Tue 12/2211:59 am -
1 stop10h 00m
Deal found 10/6![Delta logo]()
$436
This United Airlines deal was found by Cheapflights users on 10/3. 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 11/148:41 am -
1 stop5h 52m
Tue 11/171:29 pm -
1 stop5h 37m
Deal found 10/3![United Airlines logo]()
$499
This Southwest deal was found by Cheapflights users on 10/5. 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 12/248:05 am -
1 stop8h 35m
Sun 12/2711:55 pm -
Nonstop3h 45m
Deal found 10/5![Southwest logo]()
$483
This United Airlines deal was found by Cheapflights users on 10/5. 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 1/2310:40 am -
2 stops11h 21m
Tue 1/261:42 pm -
1 stop5h 28m
Deal found 10/5![United Airlines logo]()
$504
This United Airlines deal was found by Cheapflights users on 10/4. 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 11/194:15 pm -
Nonstop4h 32m
Mon 11/237:00 am -
Nonstop4h 00m
Deal found 10/4![United Airlines logo]()
$508
This American Airlines deal was found by Cheapflights users on 10/5. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/206:02 am -
2 stops11h 14m
Sat 10/241:05 pm -
2 stops9h 04m
Deal found 10/5![American Airlines logo]()
$810
This United Airlines deal was found by Cheapflights users on 10/2. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 12/197:52 pm -
Nonstop4h 39m
Thu 12/2411:52 pm -
Nonstop3h 55m
Deal found 10/2![United Airlines logo]()
$508
This American Airlines deal was found by Cheapflights users on 10/3. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 11/277:11 am -
2 stops12h 02m
Mon 11/302:09 pm -
1 stop5h 53m
Deal found 10/3![American Airlines logo]()
$818
This United Airlines deal was found by Cheapflights users on 10/4. 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 10/248:45 am -
1 stop6h 01m
Sat 10/315:00 am -
2 stops9h 47m
Deal found 10/4![United Airlines logo]()
$539
This American Airlines deal was found by Cheapflights users on 10/7. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/222:30 pm -
2 stops10h 23m
Mon 10/261:05 pm -
2 stops8h 54m
Deal found 10/7![American Airlines logo]()
$947
This United Airlines deal was found by Cheapflights users on 10/2. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/98:53 am -
2 stops13h 45m
Wed 12/167:00 am -
1 stop9h 14m
Deal found 10/2![United Airlines logo]()
$610
This United Airlines deal was found by Cheapflights users on 10/7. 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.
Wed 3/310:35 am -
2 stops11h 45m
Thu 3/251:00 pm -
1 stop6h 03m
Deal found 10/7![United Airlines logo]()
$654
This Delta deal was found by Cheapflights users on 10/7. 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 10/224:26 pm -
1 stop7h 28m
Mon 10/2612:16 pm -
1 stop8h 20m
Deal found 10/7![Delta logo]()
$992
This United Airlines deal was found by Cheapflights users on 10/5. 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 10/2310:49 am -
2 stops14h 02m
Tue 10/276:59 am -
1 stop8h 44m
Deal found 10/5![United Airlines logo]()
$668
Last-minute flights from Illinois to OntarioDiscover last-minute flight deals from Illinois to Ontario. Data last updated October 7, 2026 and is based on user searches.
Discover last-minute flight deals from Illinois to Ontario. Data last updated October 7, 2026 and is based on user searches.
This CheapOair deal was found by Cheapflights users on 10/5. 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.
Wed 10/146:30 am -
1 stop5h 59m
Wed 10/2111:52 am -
1 stop10h 32m
Deal found 10/5![Frontier logo]()
$190
This FlightHub deal was found by Cheapflights users on 10/5. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/206:30 am -
1 stop5h 59m
Sat 10/2411:52 am -
1 stop10h 32m
Deal found 10/5![Frontier logo]()
$187
This Frontier deal was found by Cheapflights users on 10/5. 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 10/208:30 am -
1 stop10h 18m
Fri 10/2311:52 am -
1 stop10h 32m
Deal found 10/5![Frontier logo]()
$192
This CheapOair deal was found by Cheapflights users on 10/5. 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.
Mon 10/263:30 pm -
1 stop26h 51m
Mon 11/26:30 am -
1 stop15h 51m
Deal found 10/5![Frontier logo]()
$195
This Cheapflightsfares deal was found by Cheapflights users on 10/5. 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 11/46:30 am -
1 stop6h 05m
Thu 11/122:23 pm -
1 stop12h 50m
Deal found 10/5![Frontier logo]()
$198
This Frontier deal was found by Cheapflights users on 10/5. 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 11/56:30 am -
1 stop6h 05m
Wed 11/1111:52 am -
1 stop10h 29m
Deal found 10/5![Frontier logo]()
$179
This Cheapflightsfares deal was found by Cheapflights users on 10/5. 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.
Thu 11/510:29 am -
1 stop10h 39m
Fri 11/68:35 pm -
1 stop6h 38m
Deal found 10/5![Frontier logo]()
$189
This Frontier deal was found by Cheapflights users on 10/5. 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
Sat 11/711:52 am -
1 stop10h 29m
Deal found 10/5![Frontier logo]()
$191
This Frontier deal was found by Cheapflights users on 10/5. 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
Mon 11/168:35 pm -
1 stop6h 38m
Deal found 10/5![Frontier logo]()
$178
This CheapOair deal was found by Cheapflights users on 10/5. 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 11/108:59 am -
1 stop9h 39m
Mon 11/168:35 pm -
1 stop6h 38m
Deal found 10/5![Frontier logo]()
$183
This CheapOair deal was found by Cheapflights users on 10/5. 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 11/1410:29 am -
1 stop8h 09m
Tue 11/176:30 am -
1 stop15h 51m
Deal found 10/5![Frontier logo]()
$188
This Frontier deal was found by Cheapflights users on 10/6. 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 11/265:25 am -
1 stop13h 58m
Sat 12/52:41 pm -
1 stop12h 20m
Deal found 10/6![Frontier logo]()
$200
One-way flights from Illinois to OntarioSearch for one-way flight options from Illinois to Ontario. Find affordable one-way fares based on user searches. Data last updated October 7, 2026.
Search for one-way flight options from Illinois to Ontario. Find affordable one-way fares based on user searches. Data last updated October 7, 2026.
This Super.com deal was found by Cheapflights users on 10/6. 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.
Fri 11/66:30 am -
1 stop6h 12m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 10/6![Frontier logo]()
$118
This Trip.com deal was found by Cheapflights users on 10/7. 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.
Tue 12/16:21 am -
1 stop7h 11m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 10/7![Frontier logo]()
$119
This Mytrip deal was found by Cheapflights users on 10/6. 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.
Fri 10/306:30 am -
1 stop6h 12m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 10/6![Frontier logo]()
$120
This Super.com deal was found by Cheapflights users on 10/7. 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 10/2810:40 am -
1 stop7h 58m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 10/7![Frontier logo]()
$121
This Super.com deal was found by Cheapflights users on 10/7. 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 10/2912:20 pm -
1 stop8h 48m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 10/7![Frontier logo]()
$121
This eDestinos deal was found by Cheapflights users on 10/7. 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 eDestinos is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/193:30 pm -
1 stop27h 00m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 10/7![Frontier logo]()
$122
This Frontier deal was found by Cheapflights users on 10/7. 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 11/176:30 am -
1 stop6h 05m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 10/7![Frontier logo]()
$123
This Super.com deal was found by Cheapflights users on 10/4. 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.
Sat 10/246:30 am -
1 stop5h 59m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 10/4![Frontier logo]()
$125
This Kiwi.com deal was found by Cheapflights users on 10/7. 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.
Sat 11/146:30 am -
2 stops33h 08m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 10/7![Frontier logo]()
$126
This Super.com deal was found by Cheapflights users on 10/7. 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 10/1512:26 pm -
1 stop8h 39m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 10/7![Frontier logo]()
$127
This Super.com deal was found by Cheapflights users on 10/7. 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 10/221:12 pm -
1 stop7h 53m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 10/7![Frontier logo]()
$127
This Frontier deal was found by Cheapflights users on 10/3. 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 11/186:30 am -
1 stop6h 05m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 10/3![Frontier logo]()
$129
Find flight deals from Illinois to Ontario
Keep the following information in mind while searching for Illinois to Ontario flight deals. Data was last updated October 7, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $178 (Frontier) |
One-way from | $118 (Super.com) |
Popular in | June |
Cheapest in | October |
Average price | $262 |
Good round-trip deal | $239 or less |
Good one-way deal | $119 or less |
Cheapflights Fare Finder
Customize your flight search to find flights from Illinois 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 October 7, 2026.
Use the filters below to find and compare flights from Illinois to Ontario that are best for you.
Fly from
Fly to
Route
Depart
Return
Cheapest round-trip
ChicagoOntario
ORD Chicago O'Hare Intl - ONT Ontario
ORDONT
Chicago O'Hare Intl
Tue 1/5
5:15 pm-10:48 pm
1 stop7h 33m
Ontario
Wed 12/31
12:00 am-2:00 am
Nonstop0h 00m
$153
ChicagoOntario
MDW Chicago Midway - ONT Ontario
MDWONT
Chicago Midway
Sat 12/5
6:00 am-4:28 pm
2 stops12h 28m
Ontario
Wed 12/31
12:00 am-2:00 am
Nonstop0h 00m
$158
ChicagoOntario
ORD Chicago O'Hare Intl - ONT Ontario
ORDONT
Chicago O'Hare Intl
Wed 11/4
9:59 am-4:23 pm
2 stops8h 24m
Ontario
Wed 12/31
12:00 am-2:00 am
Nonstop0h 00m
$164
ChicagoOntario
ORD Chicago O'Hare Intl - ONT Ontario
ORDONT
Chicago O'Hare Intl
Sat 12/5
9:59 am-10:59 pm
2 stops15h 00m
Ontario
Wed 12/31
12:00 am-2:00 am
Nonstop0h 00m
$164
ChicagoOntario
ORD Chicago O'Hare Intl - ONT Ontario
ORDONT
Chicago O'Hare Intl
Sun 11/8
5:27 am-11:06 am
1 stop7h 39m
Ontario
Wed 12/31
12:00 am-2:00 am
Nonstop0h 00m
$180
ChicagoOntario
MDW Chicago Midway - ONT Ontario
MDWONT
Chicago Midway
Wed 11/4
10:12 am-4:23 pm
2 stops8h 11m
Ontario
Wed 12/31
12:00 am-2:00 am
Nonstop0h 00m
$185
ChicagoOntario
MDW Chicago Midway - ONT Ontario
MDWONT
Chicago Midway
Sat 11/21
10:34 am-11:00 pm
2 stops14h 26m
Ontario
Wed 12/31
12:00 am-2:00 am
Nonstop0h 00m
$185
ChicagoOntario
ORD Chicago O'Hare Intl - ONT Ontario
ORDONT
Chicago O'Hare Intl
Sat 11/21
9:59 am-11:00 pm
2 stops15h 01m
Ontario
Wed 12/31
12:00 am-2:00 am
Nonstop0h 00m
$185
ChicagoOntario
ORD Chicago O'Hare Intl - ONT Ontario
ORDONT
Chicago O'Hare Intl
Mon 11/23
4:15 pm-6:47 pm
Nonstop4h 32m
Ontario
Wed 12/31
12:00 am-2:00 am
Nonstop0h 00m
$195
Quickest round-trip
ChicagoOntario
MDW Chicago Midway - ONT Ontario
MDWONT
Chicago Midway
Fri 12/11
10:45 am-1:05 pm
Nonstop4h 20m
Ontario
Wed 12/31
12:00 am-2:00 am
Nonstop0h 00m
$202
Showing 1-10 of 59 resultsSorted by cheapest first
Best time to book a flight from Illinois to Ontario
Have a flexible travel schedule? Discover the best time to fly to Ontario from Illinois with our price prediction graph.
ORD-ONT
MDW-ONT
MLI-ONT
PIA-ONT
SPI-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 Illinois to Ontario
USIL-ONT
ORD-ONT
MDW-ONT
MLI-ONT
PIA-ONT
What is the cheapest month to book a flight from Illinois to Ontario?
Currently, October is the cheapest month in which you can book a flight from Illinois to Ontario (average of $337). Flying from Illinois to Ontario in July is currently the most expensive (average of $531). 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 IL to ONT?
Find hourly flight availability from Illinois 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 October 7, 2026.
It’s typically best to fly out from Illinois to Ontario at noon. Doing so could potentially save you 70% on the flight price compared to flying in the evening, which is usually more expensive.
How much does it cost to fly round-trip from Illinois to Ontario?
Airfare is below average for this route at the moment.
Illinois to Ontario flights typically cost between $258 and $514 in November.The cheapest round-trip price found within the last 5 days was $178 on Frontier (Nov 7-Nov 12).
How far ahead should I book a flight from Illinois to Ontario?
The best time to book flights from Illinois to Ontario is 52 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.
Related info for your journey
Find useful and relevant information for your journey from Illinois to Ontario. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.
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.
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Alternative routes for Illinois to Ontario
See prices for flight routes from nearby airports that may be better suited for you.
Complete your trip
Complete your trip to Ontario by adding a car rental and/or hotel reservation to your travel itinerary.
Search flights from Illinois to Ontario by cabin class
Find flights from Illinois 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 October 7, 2026.
Illinois and Ontario flights
Browse other Illinois and Ontario flight options. Last updated on October 7, 2026.
Popular flight searches
Check out other popular destinations found by fellow travelers in 2026
Illinois to Ontario flights
Consider these flights traveling from Illinois to Ontario.
Top 5 airlines flying from Illinois to Ontario
Discover the top 5 airlines that operate flights from Illinois 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 October 7, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$188 | Average$293 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$236 | Average$359 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$239 | Average$453 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$276 | Average$535 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$276 | Average$536 | FlexibilityNo cancel fee | On-time71% |