$54+ 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 2/8. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — DEN
feb. 19 — feb. 261
1 adult, Economy
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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 Ontario to Colorado
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 enero 20, 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 enero 20, 2026.
This Frontier deal was found by Cheapflights users on 1/19. 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.
jue. 2/196:05 am
ONT
- DEN
Nonstop2h 20m
Frontier
dom. 2/226:20 am
DEN
- ONT
Nonstop2h 39m
Frontier
Deal found 1/19![Frontier logo]()
$63
This Frontier deal was found by Cheapflights users on 1/20. 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.
jue. 2/122:08 pm
ONT
- DEN
Nonstop2h 23m
Frontier
sáb. 2/1410:29 pm
DEN
- ONT
Nonstop2h 30m
Frontier
Deal found 1/20![Frontier logo]()
$66
This Super.com deal was found by Cheapflights users on 1/19. 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.
dom. 2/156:10 am
ONT
- DEN
Nonstop2h 20m
Frontier
dom. 2/226:20 am
DEN
- ONT
Nonstop2h 39m
Frontier
Deal found 1/19![Frontier logo]()
$67
This CheapOair deal was found by Cheapflights users on 1/20. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lun. 2/96:20 am
ONT
- DEN
Nonstop2h 20m
Frontier
mar. 2/108:00 pm
DEN
- ONT
Nonstop2h 34m
Frontier
Deal found 1/20![Frontier logo]()
$68
This Super.com deal was found by Cheapflights users on 1/18. 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.
mar. 2/108:36 am
ONT
- DEN
Nonstop2h 24m
Frontier
sáb. 3/710:29 pm
DEN
- ONT
Nonstop2h 30m
Frontier
Deal found 1/18![Frontier logo]()
$69
This Super.com deal was found by Cheapflights users on 1/19. 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.
mié. 2/118:10 am
ONT
- DEN
Nonstop2h 24m
Frontier
jue. 2/198:00 am
DEN
- ONT
Nonstop2h 34m
Frontier
Deal found 1/19![Frontier logo]()
$70
This CheapOair deal was found by Cheapflights users on 1/19. 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.
mar. 2/178:35 am
ONT
- DEN
Nonstop2h 24m
Frontier
sáb. 2/2110:29 pm
DEN
- ONT
Nonstop2h 30m
Frontier
Deal found 1/19![Frontier logo]()
$71
This CheapOair deal was found by Cheapflights users on 1/20. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
sáb. 2/216:00 am
ONT
- DEN
Nonstop2h 20m
Frontier
dom. 3/16:20 am
DEN
- ONT
Nonstop2h 39m
Frontier
Deal found 1/20![Frontier logo]()
$72
This Booking.com deal was found by Cheapflights users on 1/19. 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.
sáb. 3/76:15 am
ONT
- DEN
Nonstop2h 20m
Frontier
dom. 3/810:29 pm
DEN
- ONT
Nonstop2h 30m
Frontier
Deal found 1/19![Frontier logo]()
$73
This Kiwi.com deal was found by Cheapflights users on 1/20. 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.
mar. 3/246:15 am
ONT
- DEN
Nonstop2h 20m
Frontier
mar. 3/3110:29 pm
DEN
- ONT
Nonstop2h 30m
Frontier
Deal found 1/20![Frontier logo]()
$74
This Super.com deal was found by Cheapflights users on 1/19. 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.
mar. 2/108:36 am
ONT
- DEN
Nonstop2h 24m
Frontier
vie. 2/1310:29 pm
DEN
- ONT
Nonstop2h 30m
Frontier
Deal found 1/19![Frontier logo]()
$75
This Flightnetwork deal was found by Cheapflights users on 1/20. 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 Flightnetwork is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mié. 2/187:30 am
ONT
- DEN
Nonstop2h 25m
Frontier
mié. 2/258:00 pm
DEN
- ONT
Nonstop2h 34m
Frontier
Deal found 1/20![Frontier logo]()
$76
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 enero 20, 2026.
Most accurate provider | CheapOair 3 stars |
|---|---|
Most trusted provider | CheapOair 3 stars |
Round-trip from | $62 (Frontier) |
One-way from | $54 (Expedia) |
Popular in | June |
Cheapest in | September |
Average price | $197 |
Good round-trip deal | $190 or less |
Good one-way deal | $124 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 enero 20, 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
mar. 3/24
1:20 pm-7:57 pm
1 stop5h 37m
Denver Intl
sáb. 3/28
6:15 pm-10:48 pm
1 stop5h 33m
$197
OntarioDenver
ONT - DEN
ONTDEN
Ontario
jue. 4/16
6:49 pm-12:45 am
1 stop4h 56m
Denver Intl
sáb. 4/18
11:15 am-12:38 pm
Nonstop2h 23m
$203
OntarioDenver
ONT - DEN
ONTDEN
Ontario
jue. 3/5
1:10 pm-8:14 pm
1 stop6h 04m
Denver Intl
sáb. 3/7
7:00 am-12:07 pm
1 stop6h 07m
$205
OntarioMontrose
ONT - MTJ
ONTMTJ
Ontario
vie. 2/6
5:05 am-12:30 pm
1 stop6h 25m
Montrose County
dom. 2/8
4:07 pm-10:53 pm
1 stop7h 46m
$211
OntarioGrand Junction
ONT - GJT
ONTGJT
Ontario
vie. 2/6
5:10 pm-10:02 pm
1 stop3h 52m
Grand Junction Regnl
dom. 2/8
7:40 am-12:16 pm
1 stop5h 36m
$211
OntarioGrand Junction
ONT - GJT
ONTGJT
Ontario
vie. 2/6
5:05 am-10:54 am
1 stop4h 49m
Grand Junction Regnl
dom. 2/8
7:00 am-12:47 pm
1 stop6h 47m
$211
OntarioColorado Springs
ONT - COS
ONTCOS
Ontario
mié. 2/11
5:05 am-10:57 am
1 stop4h 52m
Colorado Springs
mié. 2/11
3:30 pm-8:58 pm
1 stop6h 28m
$213
OntarioColorado Springs
ONT - COS
ONTCOS
Ontario
mar. 2/17
5:00 pm-10:21 pm
1 stop4h 21m
Colorado Springs
mar. 2/24
12:00 pm-4:02 pm
1 stop5h 02m
$213
OntarioColorado Springs
ONT - COS
ONTCOS
Ontario
jue. 2/12
6:00 am-11:15 am
1 stop4h 15m
Colorado Springs
mar. 2/17
7:55 am-12:07 pm
1 stop5h 12m
$213
OntarioColorado Springs
ONT - COS
ONTCOS
Ontario
mié. 2/25
5:00 am-10:52 am
1 stop4h 52m
Colorado Springs
sáb. 2/28
8:00 am-12:43 pm
1 stop5h 43m
$213
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.
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
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 $36). Flying from Ontario to Colorado in September is currently the most expensive (average of $76). 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 enero 20, 2026.
It’s typically best to fly out from Ontario to Colorado in the evening. Doing so could potentially save you 54% 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 January 17, 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 enero 20, 2026.
The most flights from ONT to USCO are scheduled on a Monday (10 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (3 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 enero 20, 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.
Comfort
8.0
Boarding
8.1
Food
7.0
Entertainment
7.5
Crew
8.6
Overall
8.0
Reviews
1 / 20
2.0
MediocreThomas,Dec 2025
SEA - DEN
Comfort
8.0
Boarding
8.1
Food
7.0
Entertainment
7.5
Crew
8.6
Overall
8.0
Reviews
1 / 20
2.0
MediocreThomas,Dec 2025
SEA - DEN
Comfort
8.0
Boarding
8.1
Food
7.0
Entertainment
7.5
Crew
8.6
Overall
8.0
Reviews
1 / 20
2.0
MediocreThomas,Dec 2025
SEA - DEN
Comfort
8.0
Boarding
8.1
Food
7.0
Entertainment
7.5
Crew
8.6
Overall
8.0
Reviews
1 / 20
2.0
MediocreThomas,Dec 2025
SEA - DEN
Comfort
8.0
Boarding
8.1
Food
7.0
Entertainment
7.5
Crew
8.6
Overall
8.0
Reviews
1 / 20
2.0
MediocreThomas,Dec 2025
SEA - DEN
Comfort
8.0
Boarding
8.1
Food
7.0
Entertainment
7.5
Crew
8.6
Overall
8.0
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.
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 enero 20, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$58 | Average$147 | 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$348 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$211 | Average$373 | FlexibilityNo cancel fee | On-time71% |