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$42+ 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 5/7. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — DEN
Apr 20 — Apr 271
Sun 4/20
Sun 4/27
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 April 15, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

eDreams
3 stars

Round-trip from

$78
(Frontier)

One-way from

$42
(Mytrip)

Popular in

December

Cheapest in

January

Average price

$187

Good round-trip deal

$194 or less

Good one-way deal

$126 or less
Provider with most accurate pricing for Los Angeles-Denver Intl flight deals.
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Provider most trusted by Cheapflights users for Los Angeles-Denver Intl flights.
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From Ontario to Colorado
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One-way flight from Ontario to Colorado
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High demand for flights, 0% potential price rise
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Cheapest flight prices on average. 1% potential price decrease ($4 potential savings vs. average RT price).
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Average for round-trip flights in April 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 April 15, 2025.

This Frontier deal was found by Cheapflights users on 4/15. 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 5/612:59 amONT - DEN
Nonstop2h 18mFrontier
Wed 5/149:43 pmDEN - ONT
Nonstop2h 25mFrontier
Deal found 4/15$78
This Southwest deal was found by Cheapflights users on 4/14. 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 5/85:35 amONT - DEN
Nonstop2h 10mSouthwest
Mon 5/127:05 pmDEN - ONT
Nonstop2h 20mSouthwest
Deal found 4/14$137
This United Airlines deal was found by Cheapflights users on 4/14. 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 5/74:15 pmONT - DEN
Nonstop2h 20mUnited Airlines
Sun 5/111:45 pmDEN - ONT
Nonstop2h 24mUnited Airlines
Deal found 4/14$197
This American Airlines deal was found by Cheapflights users on 4/15. 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 5/61:14 pmONT - DEN
1 stop3h 59mAmerican Airlines
Fri 5/911:16 amDEN - ONT
1 stop5h 33mAmerican Airlines
Deal found 4/15$199
This Expedia deal was found by Cheapflights users on 4/13. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/112:59 amONT - DEN
Nonstop2h 18mMultiple Airlines
Wed 5/77:00 amDEN - ONT
1 stop9h 32mMultiple Airlines
Deal found 4/13$202
This Delta deal was found by Cheapflights users on 4/13. 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 5/94:57 pmONT - DEN
1 stop4h 33mDelta
Tue 5/1312:54 pmDEN - ONT
1 stop4h 23mDelta
Deal found 4/13$217
This United Airlines deal was found by Cheapflights users on 4/15. 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 5/134:15 pmONT - COS
1 stop4h 21mUnited Airlines
Tue 5/209:00 amCOS - ONT
1 stop4h 38mUnited Airlines
Deal found 4/15$219
This Delta deal was found by Cheapflights users on 4/14. 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 5/286:00 amONT - COS
2 stops11h 53mDelta
Sat 6/78:00 amCOS - ONT
1 stop5h 15mDelta
Deal found 4/14$224
This Alaska Airlines deal was found by Cheapflights users on 4/14. 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 5/294:45 pmONT - DEN
1 stop6h 20mAlaska Airlines
Tue 6/107:05 pmDEN - ONT
1 stop5h 52mAlaska Airlines
Deal found 4/14$236
This United Airlines deal was found by Cheapflights users on 4/15. 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 5/14:15 pmONT - DRO
1 stop4h 55mUnited Airlines
Tue 5/67:00 amDRO - ONT
1 stop6h 38mUnited Airlines
Deal found 4/15$268
This Delta deal was found by Cheapflights users on 4/15. 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 5/306:00 amONT - GJT
1 stop3h 34mDelta
Thu 6/55:56 amGJT - ONT
1 stop4h 15mDelta
Deal found 4/15$269
This Southwest deal was found by Cheapflights users on 4/14. 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 6/175:25 pmONT - COS
1 stop5h 00mSouthwest
Wed 7/26:50 amCOS - ONT
1 stop5h 10mSouthwest
Deal found 4/14$287

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 April 15, 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

Tue 5/6

12:59 am-4:17 am

Nonstop2h 18m

Denver Intl

Wed 5/14

9:43 pm-11:08 pm

Nonstop2h 25m

$78

OntarioDenver

ONT - DEN

ONTDEN

Ontario

Thu 5/8

1:20 pm-4:35 pm

Nonstop2h 15m

Denver Intl

Mon 5/12

7:05 pm-8:25 pm

Nonstop2h 20m

$137

OntarioDenver

ONT - DEN

ONTDEN

Ontario

Wed 5/7

4:15 pm-7:35 pm

Nonstop2h 20m

Denver Intl

Sun 5/11

1:45 pm-3:09 pm

Nonstop2h 24m

$197

OntarioDenver

ONT - DEN

ONTDEN

Ontario

Tue 5/6

1:14 pm-6:13 pm

1 stop3h 59m

Denver Intl

Fri 5/9

11:16 am-3:49 pm

1 stop5h 33m

$199

OntarioDenver

ONT - DEN

ONTDEN

Ontario

Thu 5/1

12:59 am-4:17 am

Nonstop2h 18m

Denver Intl

Wed 5/7

7:00 am-3:32 pm

1 stop9h 32m

$202

OntarioDenver

ONT - DEN

ONTDEN

Ontario

Fri 5/9

1:10 pm-7:30 pm

1 stop5h 20m

Denver Intl

Sun 5/11

6:25 pm-11:42 pm

1 stop6h 17m

$217

OntarioColorado Springs

ONT - COS

ONTCOS

Ontario

Tue 5/13

4:15 pm-9:36 pm

1 stop4h 21m

Colorado Springs

Tue 5/20

9:00 am-12:38 pm

1 stop4h 38m

$219

OntarioColorado Springs

ONT - COS

ONTCOS

Ontario

Wed 5/28

6:00 am-6:53 pm

2 stops11h 53m

Colorado Springs

Sat 6/7

8:00 am-12:15 pm

1 stop5h 15m

$224

OntarioDenver

ONT - DEN

ONTDEN

Ontario

Thu 5/29

4:45 pm-12:05 am

1 stop6h 20m

Denver Intl

Tue 6/10

7:05 pm-11:57 pm

1 stop5h 52m

$236

OntarioDurango

ONT - DRO

ONTDRO

Ontario

Thu 5/1

4:15 pm-10:10 pm

1 stop4h 55m

Durango La Plata County

Tue 5/6

7:00 am-12:38 pm

1 stop6h 38m

$268

Flights are sorted by cheapest round-trip flights first.

Deals found on 4/14

Showing 1-10 of 43 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 April 15, 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 April 15, 2025.

The most flights from ONT to USCO are scheduled on a Monday (12 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (4 on average).

Rainfall in Colorado by month

Plan your trip to Colorado by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in Colorado ranges from 0.5 - 2.3 inches per month. May is typically the wettest month, when rainfall can reach 2.3 in. January is typically the driest time to visit Colorado when rainfall is around 0.5 in.

Temperature in Colorado by month

Plan your trip to Colorado by taking into account the average temperature totals by month.

If weather is an important factor for your trip to Colorado, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 73.4 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 30.2 F).

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 April 15, 2025.
Get a feel of what it's like to fly with Alaska Airlines, Southwest and Delta from Ontario to Colorado by reading reviews from past customers. 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
9,871 reviews

Food

7.1

Overall

8.0

Comfort

7.9

Crew

8.5

Boarding

8.2

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them
Alaska Airlines
8.0
Very good
9,871 reviews
Alaska Airlines
8.0
Very good
9,871 reviews

Food

7.1

Overall

8.0

Comfort

7.9

Crew

8.5

Boarding

8.2

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them
Southwest
8.0
Very good
4,279 reviews
Alaska Airlines
8.0
Very good
9,871 reviews

Food

7.1

Overall

8.0

Comfort

7.9

Crew

8.5

Boarding

8.2

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them
Delta
8.0
Very good
7,918 reviews
Alaska Airlines
8.0
Very good
9,871 reviews

Food

7.1

Overall

8.0

Comfort

7.9

Crew

8.5

Boarding

8.2

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them
Hawaiian Airlines
7.9
Good
2,375 reviews
Alaska Airlines
8.0
Very good
9,871 reviews

Food

7.1

Overall

8.0

Comfort

7.9

Crew

8.5

Boarding

8.2

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them
United Airlines
7.4
Good
8,658 reviews
Alaska Airlines
8.0
Very good
9,871 reviews

Food

7.1

Overall

8.0

Comfort

7.9

Crew

8.5

Boarding

8.2

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them

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 335 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 ($42), Southwest ($69), and United Airlines ($99).

  • 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 - Grand Junction Regnl.

  • 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: United Airlines (91%), Air Canada (89%), Southwest (86%).

  • What are the cheapest flights from Ontario to Colorado?

    Looking at all options, your cheapest flight can be booked for $49. While the most popular route (Ontario - Denver Intl) can be booked for $128 on average our data indicates $731 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.

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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 April 15, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$54Average$123FlexibilityNo cancel feeOn-time62%
SouthwestCheapest$97Average$344FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$132Average$400FlexibilityNo cancel feeOn-time69%
DeltaCheapest$159Average$257FlexibilityNo cancel feeOn-timeN/A
American AirlinesCheapest$218Average$411FlexibilityNo cancel feeOn-time71%

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