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Colorado

$61+ 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 7/15. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — DEN
Jul 8 — Jul 151
Tue 7/8
Tue 7/15
1 adult, Economy
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Cheap flight deals from Ontario to Colorado

Keep the following information in mind while searching for Ontario to Colorado flight deals. Data was last updated July 3, 2025.

Round-trip from

$108
(Expedia)

One-way from

$61
(Priceline)

Popular in

June

Cheapest in

January

Average price

$208

Good round-trip deal

$220 or less

Good one-way deal

$124 or less
From Ontario to Colorado
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One-way flight from Ontario to Colorado
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Highest demand for flights based on searches. 10% potential increase in price ($22 potential increase over avg. RT price).
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Cheapest flight prices on average. 2% potential price decrease ($4 potential savings vs. average RT price).
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Average for round-trip flights in July 2025
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Price to beat on a round-trip flight from Ontario to Colorado.
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Price to beat on a one-way flight from Ontario to Colorado.
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Find flight deals from Ontario to Colorado

Cheapest flights from Ontario to Colorado
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 July 3, 2025.

This Booking.com deal was found by Cheapflights users on 7/2. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 7/1012:59 amONT - DEN
Nonstop2h 20mFrontier
Mon 7/1410:29 pmDEN - ONT
Nonstop2h 21mFrontier
Deal found 7/2$108
This Southwest deal was found by Cheapflights users on 7/2. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/185:05 pmONT - COS
1 stop5h 20mSouthwest
Mon 9/223:30 pmCOS - ONT
1 stop5h 15mSouthwest
Deal found 7/2$217
This American Airlines deal was found by Cheapflights users on 6/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/257:05 pmONT - GJT
1 stop4h 12mAmerican Airlines
Sat 7/266:59 pmGJT - ONT
1 stop3h 39mAmerican Airlines
Deal found 6/30$229
This United Airlines deal was found by Cheapflights users on 7/3. 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.
Tue 8/56:31 pmONT - COS
1 stop4h 21mUnited Airlines
Fri 8/812:55 pmCOS - ONT
1 stop5h 30mUnited Airlines
Deal found 7/3$245
This American Airlines deal was found by Cheapflights users on 7/3. 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.
Tue 8/512:55 pmONT - COS
2 stops8h 27mAmerican Airlines
Fri 8/86:27 amCOS - ONT
2 stops10h 57mAmerican Airlines
Deal found 7/3$255
This Delta deal was found by Cheapflights users on 7/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/149:50 amONT - COS
1 stop6h 25mDelta
Sun 8/178:00 amCOS - ONT
1 stop5h 14mDelta
Deal found 7/1$271
This United Airlines deal was found by Cheapflights users on 7/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 7/291:34 pmONT - MTJ
1 stop6h 17mUnited Airlines
Tue 8/57:15 amMTJ - ONT
1 stop6h 17mUnited Airlines
Deal found 7/1$286
This American Airlines deal was found by Cheapflights users on 7/2. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/710:06 amONT - DRO
1 stop7h 17mAmerican Airlines
Sat 10/118:10 amDRO - ONT
1 stop6h 22mAmerican Airlines
Deal found 7/2$293
This United Airlines deal was found by Cheapflights users on 7/2. 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 8/231:19 pmONT - ASE
1 stop4h 00mUnited Airlines
Sat 8/303:25 pmASE - ONT
1 stop6h 18mUnited Airlines
Deal found 7/2$299
This United Airlines deal was found by Cheapflights users on 7/2. 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 8/161:34 pmONT - GJT
1 stop5h 56mUnited Airlines
Sat 8/233:19 pmGJT - ONT
1 stop6h 24mUnited Airlines
Deal found 7/2$301
This Delta deal was found by Cheapflights users on 6/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 7/201:15 pmONT - GJT
1 stop4h 00mDelta
Fri 7/256:50 pmGJT - ONT
1 stop5h 52mDelta
Deal found 6/30$331
This United Airlines deal was found by Cheapflights users on 7/2. 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.
Thu 9/41:15 pmONT - EGE
1 stop5h 57mUnited Airlines
Sat 9/67:20 amEGE - ONT
1 stop6h 12mUnited Airlines
Deal found 7/2$337

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 July 3, 2025.
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 7/17

12:59 am-4:19 am

Nonstop2h 20m

Denver Intl

Sun 7/20

7:49 am-9:09 am

Nonstop2h 20m

$108

OntarioColorado Springs

ONT - COS

ONTCOS

Ontario

Thu 9/18

5:05 pm-11:25 pm

1 stop5h 20m

Colorado Springs

Mon 9/22

3:30 pm-7:45 pm

1 stop5h 15m

$217

OntarioGrand Junction

ONT - GJT

ONTGJT

Ontario

Thu 7/24

5:09 pm-10:33 pm

1 stop4h 24m

Grand Junction Regnl

Sun 7/27

6:00 am-8:47 am

1 stop3h 47m

$229

OntarioColorado Springs

ONT - COS

ONTCOS

Ontario

Tue 8/5

6:31 pm-11:52 pm

1 stop4h 21m

Colorado Springs

Fri 8/8

12:55 pm-5:25 pm

1 stop5h 30m

$245

OntarioColorado Springs

ONT - COS

ONTCOS

Ontario

Tue 8/5

12:55 pm-10:22 pm

2 stops8h 27m

Colorado Springs

Fri 8/8

6:27 am-4:24 pm

2 stops10h 57m

$255

OntarioColorado Springs

ONT - COS

ONTCOS

Ontario

Thu 8/14

9:50 am-5:15 pm

1 stop6h 25m

Colorado Springs

Sun 8/17

8:00 am-12:14 pm

1 stop5h 14m

$271

OntarioGrand Junction

ONT - GJT

ONTGJT

Ontario

Thu 9/11

7:16 pm-12:14 am

1 stop3h 58m

Grand Junction Regnl

Sun 9/14

6:38 pm-9:48 pm

1 stop4h 10m

$279

OntarioMontrose

ONT - MTJ

ONTMTJ

Ontario

Tue 7/29

1:34 pm-8:51 pm

1 stop6h 17m

Montrose County

Tue 8/5

7:15 am-12:32 pm

1 stop6h 17m

$286

OntarioAspen

ONT - ASE

ONTASE

Ontario

Fri 8/8

11:59 pm-9:47 am

1 stop8h 48m

Aspen Pitkin County

Tue 8/12

4:53 pm-10:48 pm

1 stop6h 55m

$294

OntarioAspen

ONT - ASE

ONTASE

Ontario

Sat 8/23

1:19 pm-6:19 pm

1 stop4h 00m

Aspen Pitkin County

Sat 8/30

3:25 pm-8:43 pm

1 stop6h 18m

$299

Flights are sorted by cheapest round-trip flights first.

Deals found on 6/30

Showing 1-10 of 35 results
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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, October is the cheapest month in which you can book a flight from Ontario to Colorado (average of $197). Flying from Ontario to Colorado in March is currently the most expensive (average of $278). 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 July 3, 2025.

Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Ontario to Colorado as you normally would.

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 July 3, 2025.

The most flights from ONT to USCO are scheduled on a Thursday (13 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 July 3, 2025.
See what other customers who have flown with Alaska Airlines, Southwest, and Delta 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.
Alaska Airlines
8.0
Very good
10,000 reviews

Overall

8.0

Comfort

7.8

Food

7.1

Crew

8.5

Boarding

8.1

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
Alaska Airlines
8.0
Very good
10,000 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Overall

8.0

Comfort

7.8

Food

7.1

Crew

8.5

Boarding

8.1

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
Southwest
8.0
Very good
4,266 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Overall

8.0

Comfort

7.8

Food

7.1

Crew

8.5

Boarding

8.1

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
Delta
8.0
Very good
7,982 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Overall

8.0

Comfort

7.8

Food

7.1

Crew

8.5

Boarding

8.1

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
Hawaiian Airlines
7.8
Good
2,545 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Overall

8.0

Comfort

7.8

Food

7.1

Crew

8.5

Boarding

8.1

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
United Airlines
7.4
Good
8,861 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Overall

8.0

Comfort

7.8

Food

7.1

Crew

8.5

Boarding

8.1

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.

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.

  • What airport do you fly from for flights from Ontario to Colorado?

    Ontario (ONT), located 3.1 mi from the city center, is the airport you fly out of when you book flights from Ontario to Colorado.

  • How popular is this Ontario to Colorado flight route?

    The Ontario to Colorado flight path was viewed by 343 users in the past month. Keep an eye out for changes in search interest prior to high and low season.

  • What are the cheapest airlines to fly from Ontario to Colorado one-way?

    The cheapest airlines for a one-way flight from Ontario to Colorado are Frontier ($61), Southwest ($79), and Hawaiian Airlines ($84).

  • What are the most popular routes from Ontario to Colorado?

    The most popular route from Ontario to Colorado is Ontario - Denver Intl. You may also consider Ontario - Colorado Springs or Ontario - Durango La Plata County.

  • What are the most reliable airlines from Ontario to Colorado?

    Looking for the most reliable airlines to get you to your destination on time? Our data shows these are most likely to get you from Ontario to Colorado on time: SkyWest Airlines (100%), United Airlines (68%), Air Canada (66%).

  • What are the cheapest flights from Ontario to Colorado?

    Looking at all options, your cheapest flight can be booked for $86. While the most popular route (Ontario - Denver Intl) can be booked for $98 on average our data indicates $987 when flying from Ontario to Colorado.

  • Can I find deals for flights from Ontario to Colorado that include hotel bookings?

    Yes. In addition to deals on Ontario to Colorado flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Ontario to Colorado?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Ontario to Colorado.

  • Can I find deals for business class flights from Ontario to Colorado?

    Yes. Cheapflights offers flight deals from Ontario to Colorado by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

  • What is the cheapest month to book a flight from Ontario to Colorado?

    Currently, October is the cheapest month in which you can book a flight from Ontario to Colorado (average of $197). Flying from Ontario to Colorado in March is currently the most expensive (average of $278). 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.

See more FAQs

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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.
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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 July 3, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$54Average$131FlexibilityNo cancel feeOn-time62%
DeltaCheapest$109Average$294FlexibilityNo cancel feeOn-timeN/A
SouthwestCheapest$111Average$351FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$135Average$378FlexibilityNo cancel feeOn-time69%
American AirlinesCheapest$288Average$397FlexibilityNo cancel feeOn-time71%

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