$59+ Cheap flights from Ontario (ONT) to Colorado
This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 4/22. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — DEN
Mar 26 — Apr 21
1 adult, Economy
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Find cheap flights from Ontario to Colorado 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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Cheapest flights from Ontario to ColoradoExplore the most affordable flight options available from Ontario to Colorado. Find the lowest fares from popular airlines and budget airlines, with prices last updated on February 24, 2026.
Explore the most affordable flight options available from Ontario to Colorado. Find the lowest fares from popular airlines and budget airlines, with prices last updated on February 24, 2026.
This Super.com deal was found by Cheapflights users on 2/23. 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.
Mon 4/1312:59 am
ONT
- DEN
Nonstop2h 16m
Frontier
Thu 4/166:05 am
DEN
- ONT
Nonstop2h 26m
Frontier
Deal found 2/23![Frontier logo]()
$78
This Kiwi.com deal was found by Cheapflights users on 2/21. 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 4/86:20 am
ONT
- DEN
Nonstop2h 23m
Frontier
Mon 4/1310:30 pm
DEN
- ONT
Nonstop2h 26m
Frontier
Deal found 2/21![Frontier logo]()
$79
This Frontier deal was found by Cheapflights users on 2/21. 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 4/2412:59 am
ONT
- DEN
Nonstop2h 16m
Frontier
Tue 4/2810:29 pm
DEN
- ONT
Nonstop2h 26m
Frontier
Deal found 2/21![Frontier logo]()
$80
This Cheapflightsfares deal was found by Cheapflights users on 2/23. 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.
Tue 4/2812:59 am
ONT
- DEN
Nonstop2h 16m
Frontier
Sun 5/36:00 am
DEN
- ONT
Nonstop2h 26m
Frontier
Deal found 2/23![Frontier logo]()
$81
This CheapOair deal was found by Cheapflights users on 2/23. 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 3/176:15 am
ONT
- DEN
Nonstop2h 20m
Frontier
Thu 3/1910:29 pm
DEN
- ONT
Nonstop2h 30m
Frontier
Deal found 2/23![Frontier logo]()
$85
This Super.com deal was found by Cheapflights users on 2/21. 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 3/256:15 am
ONT
- DEN
Nonstop2h 20m
Frontier
Tue 3/3110:29 pm
DEN
- ONT
Nonstop2h 30m
Frontier
Deal found 2/21![Frontier logo]()
$86
This Frontier deal was found by Cheapflights users on 2/20. 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 4/2312:59 am
ONT
- DEN
Nonstop2h 16m
Frontier
Wed 4/2910:29 pm
DEN
- ONT
Nonstop2h 26m
Frontier
Deal found 2/20![Frontier logo]()
$87
This Frontier deal was found by Cheapflights users on 2/21. 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 3/256:15 am
ONT
- DEN
Nonstop2h 20m
Frontier
Tue 4/710:30 pm
DEN
- ONT
Nonstop2h 26m
Frontier
Deal found 2/21![Frontier logo]()
$88
This Super.com deal was found by Cheapflights users on 2/22. 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 3/186:15 am
ONT
- DEN
Nonstop2h 20m
Frontier
Tue 3/2410:29 pm
DEN
- ONT
Nonstop2h 30m
Frontier
Deal found 2/22![Frontier logo]()
$89
This Super.com deal was found by Cheapflights users on 2/23. 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.
Sun 4/1912:59 am
ONT
- DEN
Nonstop2h 16m
Frontier
Wed 4/2210:29 pm
DEN
- ONT
Nonstop2h 26m
Frontier
Deal found 2/23![Frontier logo]()
$90
This Cheapflightsfares deal was found by Cheapflights users on 2/21. 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.
Tue 3/246:15 am
ONT
- DEN
Nonstop2h 20m
Frontier
Tue 4/710:30 pm
DEN
- ONT
Nonstop2h 26m
Frontier
Deal found 2/21![Frontier logo]()
$91
This Super.com deal was found by Cheapflights users on 2/21. 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 4/1512:59 am
ONT
- DEN
Nonstop2h 16m
Frontier
Mon 4/206:05 am
DEN
- ONT
Nonstop2h 26m
Frontier
Deal found 2/21![Frontier logo]()
$92
Best flights from Ontario to ColoradoDiscover carefully curated flight deals from Ontario to Colorado that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated February 24, 2026.
Discover carefully curated flight deals from Ontario to Colorado that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated February 24, 2026.
This Delta deal was found by Cheapflights users on 2/21. 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 3/265:09 pm
ONT
- DEN
1 stop4h 22m
Delta
Tue 3/316:15 pm
DEN
- ONT
1 stop6h 36m
Delta
Deal found 2/21![Delta logo]()
$205
This United Airlines deal was found by Cheapflights users on 2/20. 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 3/245:15 am
ONT
- DRO
1 stop4h 43m
United Airlines
Tue 3/317:00 am
DRO
- ONT
1 stop6h 38m
United Airlines
Deal found 2/20![United Airlines logo]()
$233
This Southwest deal was found by Cheapflights users on 2/20. 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 3/2410:35 am
ONT
- MTJ
2 stops8h 20m
Southwest
Tue 3/3112:35 pm
MTJ
- ONT
2 stops7h 50m
Southwest
Deal found 2/20![Southwest logo]()
$264
This American Airlines deal was found by Cheapflights users on 2/22. 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 7/97:02 pm
ONT
- DRO
1 stop4h 03m
American Airlines
Mon 7/136:00 am
DRO
- ONT
1 stop3h 32m
American Airlines
Deal found 2/22![American Airlines logo]()
$328
This Kiwi.com deal was found by Cheapflights users on 2/24. 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 5/97:18 pm
ONT
- GJT
1 stop16h 25m
Multiple Airlines
Thu 5/1412:53 pm
GJT
- ONT
2 stops19h 38m
Multiple Airlines
Deal found 2/24![Multiple Airlines logo]()
$343
This Alaska Airlines deal was found by Cheapflights users on 2/20. 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.
Thu 3/124:02 pm
ONT
- DEN
1 stop6h 57m
Alaska Airlines
Mon 3/167:00 am
DEN
- ONT
2 stops17h 52m
Alaska Airlines
Deal found 2/20![Alaska Airlines logo]()
$365
This Delta deal was found by Cheapflights users on 2/20. 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 3/141:20 pm
ONT
- DEN
1 stop5h 37m
Delta
Wed 3/186:15 pm
DEN
- ONT
1 stop6h 36m
Delta
Deal found 2/20![Delta logo]()
$205
This United Airlines deal was found by Cheapflights users on 2/20. 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 3/245:15 am
ONT
- MTJ
1 stop6h 17m
United Airlines
Tue 3/317:15 am
MTJ
- ONT
1 stop6h 23m
United Airlines
Deal found 2/20![United Airlines logo]()
$245
This United Airlines deal was found by Cheapflights users on 2/21. 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.
Sun 4/195:10 am
ONT
- DRO
1 stop4h 44m
United Airlines
Sat 4/253:23 pm
DRO
- ONT
1 stop6h 13m
United Airlines
Deal found 2/21![United Airlines logo]()
$270
This Delta deal was found by Cheapflights users on 2/22. 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 4/35:09 pm
ONT
- GJT
1 stop3h 44m
Delta
Sat 4/117:45 am
GJT
- ONT
1 stop5h 38m
Delta
Deal found 2/22![Delta logo]()
$275
This United Airlines deal was found by Cheapflights users on 2/23. 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 3/186:37 pm
ONT
- DEN
1 stop4h 53m
United Airlines
Sat 3/215:47 pm
DEN
- ONT
1 stop6h 10m
United Airlines
Deal found 2/23![United Airlines logo]()
$275
This Southwest deal was found by Cheapflights users on 2/20. 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 4/165:05 pm
ONT
- COS
1 stop5h 45m
Southwest
Sun 4/195:30 am
COS
- ONT
2 stops6h 35m
Southwest
Deal found 2/20![Southwest logo]()
$338
This Delta deal was found by Cheapflights users on 2/22. 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 4/105:09 pm
ONT
- COS
1 stop3h 56m
Delta
Sat 4/118:15 am
COS
- ONT
1 stop5h 08m
Delta
Deal found 2/22![Delta logo]()
$285
This Delta deal was found by Cheapflights users on 2/23. 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 3/1311:59 am
ONT
- DEN
1 stop10h 30m
Delta
Mon 3/166:15 pm
DEN
- ONT
1 stop6h 36m
Delta
Deal found 2/23![Delta logo]()
$288
This Alaska Airlines deal was found by Cheapflights users on 2/20. 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.
Thu 3/196:00 am
ONT
- DEN
1 stop16h 56m
Alaska Airlines
Mon 3/237:00 am
DEN
- ONT
1 stop27h 39m
Alaska Airlines
Deal found 2/20![Alaska Airlines logo]()
$385
This United Airlines deal was found by Cheapflights users on 2/20. 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 3/235:15 am
ONT
- DEN
Nonstop2h 17m
United Airlines
Sat 3/287:20 pm
DEN
- ONT
Nonstop2h 30m
United Airlines
Deal found 2/20![United Airlines logo]()
$298
This KAYAK deal was found by Cheapflights users on 2/22. 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.
Fri 3/206:15 am
ONT
- ASE
1 stop4h 34m
American Airlines
Mon 3/2310:24 am
ASE
- ONT
1 stop6h 58m
American Airlines
Deal found 2/22![American Airlines logo]()
$419
This United Airlines deal was found by Cheapflights users on 2/22. 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 3/241:50 pm
ONT
- GJT
1 stop5h 47m
United Airlines
Tue 3/315:30 am
GJT
- ONT
2 stops7h 44m
United Airlines
Deal found 2/22![United Airlines logo]()
$300
This Delta deal was found by Cheapflights users on 2/23. 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 5/206:00 am
ONT
- COS
1 stop4h 15m
Delta
Sun 5/248:15 am
COS
- ONT
1 stop5h 04m
Delta
Deal found 2/23![Delta logo]()
$333
This American Airlines deal was found by Cheapflights users on 2/21. 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.
Sun 3/811:58 pm
ONT
- DRO
1 stop8h 54m
American Airlines
Thu 3/1211:34 am
DRO
- ONT
1 stop5h 48m
American Airlines
Deal found 2/21![American Airlines logo]()
$450
This United Airlines deal was found by Cheapflights users on 2/20. 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 3/71:50 pm
ONT
- MTJ
1 stop5h 16m
United Airlines
Wed 3/113:39 pm
MTJ
- ONT
1 stop6h 11m
United Airlines
Deal found 2/20![United Airlines logo]()
$330
This Delta deal was found by Cheapflights users on 2/24. 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 6/245:05 pm
ONT
- COS
1 stop4h 24m
Delta
Wed 7/15:55 pm
COS
- ONT
1 stop6h 49m
Delta
Deal found 2/24![Delta logo]()
$335
This United Airlines deal was found by Cheapflights users on 2/21. 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.
Sun 5/175:00 am
ONT
- MTJ
1 stop6h 41m
United Airlines
Sun 5/241:40 pm
MTJ
- ONT
1 stop4h 48m
United Airlines
Deal found 2/21![United Airlines logo]()
$330
This United Airlines deal was found by Cheapflights users on 2/22. 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 4/275:10 am
ONT
- MTJ
1 stop6h 31m
United Airlines
Sun 5/37:00 am
MTJ
- ONT
1 stop6h 38m
United Airlines
Deal found 2/22![United Airlines logo]()
$330
This Delta deal was found by Cheapflights users on 2/20. 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 4/175:05 pm
ONT
- COS
1 stop4h 08m
Delta
Sun 4/197:59 am
COS
- ONT
1 stop5h 15m
Delta
Deal found 2/20![Delta logo]()
$372
This United Airlines deal was found by Cheapflights users on 2/21. 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 3/111:50 pm
ONT
- MTJ
1 stop5h 16m
United Airlines
Tue 3/177:36 am
MTJ
- ONT
1 stop6h 13m
United Airlines
Deal found 2/21![United Airlines logo]()
$330
This American Airlines deal was found by Cheapflights users on 2/24. 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 3/196:15 am
ONT
- ASE
1 stop4h 34m
American Airlines
Sun 3/2210:34 am
ASE
- ONT
1 stop6h 48m
American Airlines
Deal found 2/24![American Airlines logo]()
$590
This Delta deal was found by Cheapflights users on 2/24. 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 7/185:05 pm
ONT
- GJT
1 stop3h 45m
Delta
Sat 8/17:41 am
GJT
- ONT
1 stop5h 48m
Delta
Deal found 2/24![Delta logo]()
$399
This United Airlines deal was found by Cheapflights users on 2/20. 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 3/111:50 pm
ONT
- DEN
Nonstop2h 13m
United Airlines
Wed 3/1811:20 am
DEN
- ONT
Nonstop2h 28m
United Airlines
Deal found 2/20![United Airlines logo]()
$330
This United Airlines deal was found by Cheapflights users on 2/21. 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 3/215:15 am
ONT
- DEN
Nonstop2h 17m
United Airlines
Sat 3/287:20 pm
DEN
- ONT
Nonstop2h 30m
United Airlines
Deal found 2/21![United Airlines logo]()
$333
Last-minute flights from Ontario to ColoradoDiscover last-minute flight deals from Ontario to Colorado. Data last updated February 24, 2026 and is based on user searches.
Discover last-minute flight deals from Ontario to Colorado. Data last updated February 24, 2026 and is based on user searches.
This Super.com deal was found by Cheapflights users on 2/22. 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 3/106:15 am
ONT
- DEN
Nonstop2h 20m
Frontier
Tue 3/1710:29 pm
DEN
- ONT
Nonstop2h 30m
Frontier
Deal found 2/22![Frontier logo]()
$95
This Frontier deal was found by Cheapflights users on 2/22. 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 3/116:15 am
ONT
- DEN
Nonstop2h 20m
Frontier
Tue 3/1710:29 pm
DEN
- ONT
Nonstop2h 30m
Frontier
Deal found 2/22![Frontier logo]()
$97
This CheapOair deal was found by Cheapflights users on 2/23. 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 3/176:15 am
ONT
- DEN
Nonstop2h 20m
Frontier
Thu 3/1910:29 pm
DEN
- ONT
Nonstop2h 30m
Frontier
Deal found 2/23![Frontier logo]()
$85
This WAYA deal was found by Cheapflights users on 2/22. 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 WAYA is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/176:15 am
ONT
- DEN
Nonstop2h 20m
Frontier
Tue 3/2410:01 am
DEN
- ONT
1 stop4h 27m
Frontier
Deal found 2/22![Frontier logo]()
$106
This Super.com deal was found by Cheapflights users on 2/22. 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 3/186:15 am
ONT
- DEN
Nonstop2h 20m
Frontier
Tue 3/2410:29 pm
DEN
- ONT
Nonstop2h 30m
Frontier
Deal found 2/22![Frontier logo]()
$89
This Cheapflightsfares deal was found by Cheapflights users on 2/23. 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 3/186:15 am
ONT
- DEN
Nonstop2h 20m
Frontier
Thu 3/1910:29 pm
DEN
- ONT
Nonstop2h 30m
Frontier
Deal found 2/23![Frontier logo]()
$96
This Frontier deal was found by Cheapflights users on 2/21. 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 3/246:15 am
ONT
- DEN
Nonstop2h 20m
Frontier
Wed 4/810:30 pm
DEN
- ONT
Nonstop2h 26m
Frontier
Deal found 2/21![Frontier logo]()
$80
This Cheapflightsfares deal was found by Cheapflights users on 2/21. 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.
Tue 3/246:15 am
ONT
- DEN
Nonstop2h 20m
Frontier
Tue 4/710:30 pm
DEN
- ONT
Nonstop2h 26m
Frontier
Deal found 2/21![Frontier logo]()
$91
This Super.com deal was found by Cheapflights users on 2/21. 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 3/256:15 am
ONT
- DEN
Nonstop2h 20m
Frontier
Tue 3/3110:29 pm
DEN
- ONT
Nonstop2h 30m
Frontier
Deal found 2/21![Frontier logo]()
$86
This Frontier deal was found by Cheapflights users on 2/21. 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 3/256:15 am
ONT
- DEN
Nonstop2h 20m
Frontier
Tue 4/710:30 pm
DEN
- ONT
Nonstop2h 26m
Frontier
Deal found 2/21![Frontier logo]()
$88
This Frontier deal was found by Cheapflights users on 2/23. 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 3/256:15 am
ONT
- DEN
Nonstop2h 20m
Frontier
Wed 4/110:30 pm
DEN
- ONT
Nonstop2h 26m
Frontier
Deal found 2/23![Frontier logo]()
$94
This Kiwi.com deal was found by Cheapflights users on 2/23. 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.
Mon 3/309:49 pm
ONT
- DEN
1 stop5h 07m
Frontier
Wed 4/110:30 pm
DEN
- ONT
Nonstop2h 26m
Frontier
Deal found 2/23![Frontier logo]()
$107
One-way flights from Ontario to ColoradoSearch for one-way flight options from Ontario to Colorado. Find affordable one-way fares based on user searches. Data last updated February 24, 2026.
Search for one-way flight options from Ontario to Colorado. Find affordable one-way fares based on user searches. Data last updated February 24, 2026.
This Kiwi.com deal was found by Cheapflights users on 2/23. 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 4/2211:44 am
ONT
- DEN
1 stop11h 35m
Frontier
Deal found 2/23![Frontier logo]()
$59
This Kiwi.com deal was found by Cheapflights users on 2/23. 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 4/1411:44 am
ONT
- DEN
1 stop7h 16m
Frontier
Deal found 2/23![Frontier logo]()
$60
This Kiwi.com deal was found by Cheapflights users on 2/21. 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.
Sun 5/175:33 pm
ONT
- DEN
Nonstop2h 25m
Frontier
Deal found 2/21![Frontier logo]()
$62
This Super.com deal was found by Cheapflights users on 2/20. 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 3/106:15 am
ONT
- DEN
Nonstop2h 20m
Frontier
Deal found 2/20![Frontier logo]()
$63
This Super.com deal was found by Cheapflights users on 2/20. 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 3/186:15 am
ONT
- DEN
Nonstop2h 20m
Frontier
Deal found 2/20![Frontier logo]()
$66
This Kiwi.com deal was found by Cheapflights users on 2/23. 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.
Mon 5/118:59 pm
ONT
- DEN
1 stop6h 00m
Frontier
Deal found 2/23![Frontier logo]()
$67
This Kiwi.com deal was found by Cheapflights users on 2/24. 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.
Mon 4/139:02 pm
ONT
- DEN
1 stop5h 57m
Frontier
Deal found 2/24![Frontier logo]()
$68
This WAYA deal was found by Cheapflights users on 2/23. 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 WAYA is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/172:23 pm
ONT
- DEN
1 stop8h 56m
Frontier
Deal found 2/23![Frontier logo]()
$69
This Kiwi.com deal was found by Cheapflights users on 2/24. 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 4/79:26 pm
ONT
- DEN
1 stop5h 33m
Frontier
Deal found 2/24![Frontier logo]()
$70
This Kiwi.com deal was found by Cheapflights users on 2/20. 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.
Mon 4/611:10 am
ONT
- DEN
1 stop20h 55m
Frontier
Deal found 2/20![Frontier logo]()
$71
This Delta deal was found by Cheapflights users on 2/22. 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 4/145:05 pm
ONT
- COS
1 stop4h 08m
Delta
Deal found 2/22![Delta logo]()
$99
This United Airlines deal was found by Cheapflights users on 2/22. 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 4/1411:05 am
ONT
- COS
2 stops9h 52m
United Airlines
Deal found 2/22![United Airlines logo]()
$104
Find flight deals from Ontario to Colorado
Keep the following information in mind while searching for Ontario to Colorado flight deals. Data was last updated February 24, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $78 (Super.com) |
One-way from | $59 (Kiwi.com) |
Popular in | June |
Cheapest in | September |
Average price | $208 |
Good round-trip deal | $212 or less |
Good one-way deal | $122 or less |
Cheapflights Fare Finder
Customize your flight search to find flights from Ontario to Colorado 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 2,558,603 searches. Data last updated February 24, 2026.
Use the filters below to find and compare flights from Ontario to Colorado that are best for you.
Fly from
Ontario
Fly to
Colorado
Route
Depart
Return
Price
OntarioDenver
ONT - DEN
ONTDEN
Ontario
Thu 3/26
5:09 pm-10:31 pm
1 stop4h 22m
Denver Intl
Tue 3/31
6:15 pm-11:51 pm
1 stop6h 36m
$205
OntarioDenver
ONT - DEN
ONTDEN
Ontario
Sat 3/14
1:20 pm-7:57 pm
1 stop5h 37m
Denver Intl
Wed 3/18
6:15 pm-11:51 pm
1 stop6h 36m
$205
OntarioDurango
ONT - DRO
ONTDRO
Ontario
Tue 3/24
5:15 am-10:58 am
1 stop4h 43m
Durango La Plata County
Tue 3/31
7:00 am-12:38 pm
1 stop6h 38m
$233
OntarioMontrose
ONT - MTJ
ONTMTJ
Ontario
Tue 3/24
5:15 am-12:32 pm
1 stop6h 17m
Montrose County
Tue 3/31
7:15 am-12:38 pm
1 stop6h 23m
$245
OntarioMontrose
ONT - MTJ
ONTMTJ
Ontario
Tue 3/24
10:35 am-7:55 pm
2 stops8h 20m
Montrose County
Tue 3/31
12:35 pm-7:25 pm
2 stops7h 50m
$264
OntarioDurango
ONT - DRO
ONTDRO
Ontario
Sun 4/19
5:10 am-10:54 am
1 stop4h 44m
Durango La Plata County
Sat 4/25
3:23 pm-8:36 pm
1 stop6h 13m
$270
OntarioGrand Junction
ONT - GJT
ONTGJT
Ontario
Fri 4/3
5:09 pm-9:53 pm
1 stop3h 44m
Grand Junction Regnl
Sat 4/11
7:45 am-12:23 pm
1 stop5h 38m
$275
OntarioDenver
ONT - DEN
ONTDEN
Ontario
Wed 3/18
6:37 pm-12:30 am
1 stop4h 53m
Denver Intl
Sat 3/21
5:47 pm-10:57 pm
1 stop6h 10m
$275
OntarioColorado Springs
ONT - COS
ONTCOS
Ontario
Fri 4/10
5:09 pm-10:05 pm
1 stop3h 56m
Colorado Springs
Sat 4/11
8:15 am-12:23 pm
1 stop5h 08m
$285
OntarioDenver
ONT - DEN
ONTDEN
Ontario
Fri 3/13
11:59 am-11:29 pm
1 stop10h 30m
Denver Intl
Mon 3/16
6:15 pm-11:51 pm
1 stop6h 36m
$288
Showing 1-10 of 60 results
Best time to book a flight from Ontario to Colorado
Have a flexible travel schedule? Discover the best time to fly to Colorado from Ontario with our price prediction graph.
ONT-DEN
ONT-COS
ONT-DRO
ONT-GJT
ONT-EGE
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 Colorado
ONT-USCO
ONT-DEN
ONT-COS
ONT-DRO
ONT-GJT
What is the cheapest month to book a flight from Ontario to Colorado?
Currently, March is the cheapest month in which you can book a flight from Ontario to Colorado (average of $37). Flying from Ontario to Colorado in September is currently the most expensive (average of $75). 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 CO?
Find hourly flight availability from Ontario to Colorado. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated February 24, 2026.
It’s typically best to fly out from Ontario to Colorado in the evening. Doing so could potentially save you 51% on the flight price compared to flying at noon, which is usually more expensive.
What is the cheapest day to fly from Ontario to Colorado?
Use this chart to determine the cheapest time to fly round-trip from Ontario to Colorado. Price data was last updated on February 21, 2026.
Travelers seeking maximum savings on their Ontario to Colorado flight should consider departing on Tuesday evenings when fares are most often at their lowest. Sunday at noon flights should be avoided if possible as fares are typically the most expensive at this time.
Weekly flight availability from Ontario to Colorado
Explore weekly flight availability from Ontario to Colorado. Discover flights operating on different days of the week, giving you the flexibility to choose a travel day that best fits your plans. Compare info to find the most convenient option for your journey. Data last updated February 24, 2026.
The most flights from ONT to USCO are scheduled on a Tuesday (9 on average). You will have fewer flight options on Thursday, which is when the least amount of flights are scheduled (4 on average).
Reviews of airlines servicing Colorado
Get insights into the airlines that provide service to Colorado. 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 Colorado. Reviews last updated February 24, 2026.
See what other customers who have flown with Southwest, Delta, and United Airlines from Ontario to Colorado have to say. Users can see the overall rating for each airline as well as how each is rated in terms of entertainment options, comfort, food, crew/service, and boarding process.
Entertainment
7.5
Overall
8.0
Boarding
8.1
Comfort
8.0
Crew
8.6
Food
7.0
Reviews
1 / 20
2.0
MediocreThomas,Dec 2025
SEA - DEN
Entertainment
7.5
Overall
8.0
Boarding
8.1
Comfort
8.0
Crew
8.6
Food
7.0
Reviews
1 / 20
2.0
MediocreThomas,Dec 2025
SEA - DEN
Entertainment
7.5
Overall
8.0
Boarding
8.1
Comfort
8.0
Crew
8.6
Food
7.0
Reviews
1 / 20
2.0
MediocreThomas,Dec 2025
SEA - DEN
Entertainment
7.5
Overall
8.0
Boarding
8.1
Comfort
8.0
Crew
8.6
Food
7.0
Reviews
1 / 20
2.0
MediocreThomas,Dec 2025
SEA - DEN
Entertainment
7.5
Overall
8.0
Boarding
8.1
Comfort
8.0
Crew
8.6
Food
7.0
Reviews
1 / 20
2.0
MediocreThomas,Dec 2025
SEA - DEN
Entertainment
7.5
Overall
8.0
Boarding
8.1
Comfort
8.0
Crew
8.6
Food
7.0
Reviews
1 / 20
2.0
MediocreThomas,Dec 2025
SEA - DEN
Related info for your journey
Find useful and relevant information for your journey from Ontario to Colorado. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.
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Alternative routes for Ontario to Colorado
See prices for flight routes from nearby airports that may be better suited for you.
Complete your trip
Complete your trip to Colorado by adding a car rental and/or hotel reservation to your travel itinerary.
Search flights from Ontario to Colorado by cabin class
Find flights from Ontario to Colorado, based on your preferred cabin class, be it economy, premium economy, business, or first class.
Ontario and Colorado flights
Browse other Ontario and Colorado flight options. Last updated on February 24, 2026.
Popular flight searches
Check out other popular destinations found by fellow travelers in 2026
Ontario to Colorado flights
Consider these flights traveling from Ontario to Colorado.
Top 5 airlines flying from Ontario to Colorado
Discover the top 5 airlines that operate flights from Ontario to Colorado. 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 2,558,603 searches. Data last updated February 24, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$61 | Average$155 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$109 | Average$265 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$117 | Average$313 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$130 | Average$360 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$211 | Average$362 | FlexibilityNo cancel fee | On-time71% |