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Ontario

$27+ Cheap flights from Colorado to Ontario (ONT)

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 4/14. Fares are subject to change and may not be available on all flights or dates of travel.
DEN — ONT
3月 26 — 4月 21
週四 3/26
週四 4/2
1 adult, Economy
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Cheap flight deals from Colorado to Ontario

Cheapest flights from Colorado to Ontario
Explore the most affordable flight options available from Colorado to Ontario. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 2月 24, 2026.

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.
週三 3/1110:29 pm
DEN
-
ONT
Nonstop2h 30m
Frontier
週二 3/176:15 am
ONT
-
DEN
Nonstop2h 20m
Frontier
Deal found 2/23$97
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.
週四 3/1910:29 pm
DEN
-
ONT
Nonstop2h 30m
Frontier
週二 3/246:15 am
ONT
-
DEN
Nonstop2h 20m
Frontier
Deal found 2/21$99
This Cheapflightsfares 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
週五 4/176:05 am
DEN
-
ONT
Nonstop2h 26m
Frontier
週日 4/1912:59 am
ONT
-
DEN
Nonstop2h 16m
Frontier
Deal found 2/20$100
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.
週日 4/2610:29 pm
DEN
-
ONT
Nonstop2h 26m
Frontier
週四 4/305:43 pm
ONT
-
DEN
Nonstop2h 25m
Frontier
Deal found 2/21$101
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.
週三 5/610:29 pm
DEN
-
ONT
Nonstop2h 26m
Frontier
週二 5/127:29 pm
ONT
-
DEN
1 stop7h 30m
Frontier
Deal found 2/21$102
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.
週六 4/184:23 pm
DEN
-
ONT
1 stop7h 14m
Frontier
週六 4/1812:59 am
ONT
-
DEN
Nonstop2h 16m
Frontier
Deal found 2/21$103
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.
週三 3/1110:29 pm
DEN
-
ONT
Nonstop2h 30m
Frontier
週六 3/146:15 am
ONT
-
DEN
Nonstop2h 20m
Frontier
Deal found 2/22$105
This Frontier 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
週三 4/810:30 pm
DEN
-
ONT
1 stop10h 34m
Frontier
週五 4/106:20 am
ONT
-
DEN
Nonstop2h 23m
Frontier
Deal found 2/24$106
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.
週三 4/110:30 pm
DEN
-
ONT
Nonstop2h 26m
Frontier
週日 4/56:20 am
ONT
-
DEN
Nonstop2h 23m
Frontier
Deal found 2/22$107
This Frontier 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
週六 4/1810:29 pm
DEN
-
ONT
1 stop10h 55m
Frontier
週日 4/1912:59 am
ONT
-
DEN
Nonstop2h 16m
Frontier
Deal found 2/24$108
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.
週二 3/1712:10 pm
COS
-
ONT
1 stop5h 18m
Delta
週三 4/16:00 am
ONT
-
COS
1 stop4h 24m
Delta
Deal found 2/24$197
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.
週二 3/246:00 am
COS
-
ONT
2 stops7h 18m
United Airlines
週二 3/315:10 am
ONT
-
COS
1 stop6h 26m
United Airlines
Deal found 2/23$202

Find flight deals from Colorado to Ontario

Keep the following information in mind while searching for Colorado to Ontario flight deals. Data was last updated 2月 24, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$97
(Cheapflightsfares)

One-way from

$27
(Priceline)

Popular in

June

Cheapest in

September

Average price

$187

Good round-trip deal

$120 or less

Good one-way deal

$78 or less
Provider with most accurate pricing for Denver Intl-Los Angeles flight deals.
Search Deals
Provider most trusted by Cheapflights users for Denver Intl-Los Angeles flights.
Search Deals
From Colorado to Ontario
Search Deals
One-way flight from Colorado to Ontario
Search Deals
Highest demand for flights based on searches. 8% potential increase in price ($17 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 1% potential price decrease ($4 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in February 2026
Search Deals
Price to beat on a round-trip flight from Colorado to Ontario.
Search Deals
Price to beat on a one-way flight from Colorado to Ontario.
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Colorado to Ontario that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated 2月 24, 2026.
Use the filters below to find and compare flights from Colorado to Ontario that are best for you.

Fly from

Colorado

Fly to

Ontario

Route

Depart

Return

Price

Colorado SpringsOntario

COS - ONT

COSONT

Colorado Springs

週二 3/24

6:00 am-12:18 pm

2 stops7h 18m

Ontario

週二 3/31

5:10 am-12:36 pm

1 stop6h 26m

$202

Grand JunctionOntario

GJT - ONT

GJTONT

Grand Junction Regnl

週五 5/15

6:51 pm-11:34 pm

1 stop5h 43m

Ontario

週一 5/18

4:57 pm-10:00 pm

1 stop4h 03m

$230

DenverOntario

DEN - ONT

DENONT

Denver Intl

週三 4/22

7:10 pm-8:36 pm

Nonstop2h 26m

Ontario

週日 4/26

5:10 am-8:32 am

Nonstop2h 22m

$246

DenverOntario

DEN - ONT

DENONT

Denver Intl

週六 3/14

6:15 pm-10:48 pm

1 stop5h 33m

Ontario

週一 3/23

1:20 pm-7:57 pm

1 stop5h 37m

$268

MontroseOntario

MTJ - ONT

MTJONT

Montrose County

週二 3/10

3:39 pm-8:50 pm

1 stop6h 11m

Ontario

週六 3/14

1:50 pm-8:06 pm

1 stop5h 16m

$281

MontroseOntario

MTJ - ONT

MTJONT

Montrose County

週五 5/22

1:40 pm-5:28 pm

1 stop4h 48m

Ontario

週二 5/26

5:00 am-12:44 pm

1 stop6h 44m

$281

Grand JunctionOntario

GJT - ONT

GJTONT

Grand Junction Regnl

週六 3/7

7:05 am-12:48 pm

1 stop6h 43m

Ontario

週三 3/11

5:15 am-12:44 pm

1 stop6h 29m

$281

MontroseOntario

MTJ - ONT

MTJONT

Montrose County

週五 5/8

1:43 pm-10:59 pm

2 stops10h 16m

Ontario

週日 5/10

5:00 am-12:41 pm

1 stop6h 41m

$286

Colorado SpringsOntario

COS - ONT

COSONT

Colorado Springs

週五 4/3

8:15 am-12:23 pm

1 stop5h 08m

Ontario

週三 4/8

5:09 pm-10:05 pm

1 stop3h 56m

$292

DenverOntario

DEN - ONT

DENONT

Denver Intl

週三 5/20

8:30 am-11:55 am

1 stop4h 25m

Ontario

週四 6/11

3:40 pm-9:00 pm

1 stop4h 20m

$302

Flights are sorted by cheapest round-trip flights first.

Deals found on 2/22

Showing 1-10 of 60 results
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Best time to book a flight from Colorado to Ontario

Have a flexible travel schedule? Discover the best time to fly to Ontario from Colorado 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 Colorado to Ontario

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

Currently, April is the cheapest month in which you can book a flight from Colorado to Ontario (average of $48). Flying from Colorado to Ontario in June is currently the most expensive (average of $97). 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 CO to ONT?

Find hourly flight availability from Colorado to Ontario. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated 2月 24, 2026.

It’s optimal to fly from Colorado to Ontario in the evening. By choosing this option you can save up to 12% on the cost of your flight, compared to a flight at noon.

What is the cheapest day to fly from Colorado to Ontario?

Use this chart to determine the cheapest time to fly round-trip from Colorado to Ontario. Price data was last updated on February 21, 2026.

Travelers seeking maximum savings on their Colorado to Ontario flight should consider departing on Wednesday afternoons when fares are most often at their lowest. Sunday afternoons flights should be avoided if possible as fares are typically the most expensive at this time.

Weekly flight availability from Colorado to Ontario

Explore weekly flight availability from Colorado to Ontario. 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 2月 24, 2026.

The most flights from USCO to ONT 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).

Related info for your journey

Find useful and relevant information for your journey from Colorado to Ontario. 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 into for flights to Ontario from Colorado?

    If you book a flight to Ontario from Colorado, you will be flying to Ontario, which is the city’s only airport. Ontario (ONT) is located 3.1 mi from the center of Ontario.

  • How popular is this Colorado to Ontario flight route?

    The Colorado to Ontario flight path was viewed by 61 users in the past month. Keep an eye out for changes in search interest prior to high and low season.

  • How long is the flight from Colorado to Ontario?

    For as low as $302, United Airlines can have you in Ontario from Colorado in 4h 25m. The distance between Colorado and Ontario is about 817 mi. Both multi-stop and nonstop flights can be found to your destination and back.

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

    The cheapest airlines for a one-way flight from Colorado to Ontario are Frontier ($39), Southwest ($78), and United Airlines ($78).

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

    While some choose either Colorado Springs - Ontario or Grand Junction Regnl - Ontario, Denver Intl - Ontario is the most popular route from Colorado to Ontario.

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

    No one likes to see their flight delayed. When booking a flight from Colorado to Ontario consider choosing United Airlines (90%), Air Canada (89%) or Volaris (74%) as they are the most reliable in getting you off to your destination on time.

  • What are the cheapest flights from Colorado to Ontario?

    While on average a flight from Colorado to Ontario is generally $160, our data shows the cheapest flight currently is $49. When looking at the most popular route, (Denver Intl - Ontario), you can expect to pay $80 for that flight.

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

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

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

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

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

    Yes. Cheapflights offers flight deals from Colorado to Ontario 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 Colorado to Ontario?

    Currently, April is the cheapest month in which you can book a flight from Colorado to Ontario (average of $48). Flying from Colorado to Ontario in June is currently the most expensive (average of $97). 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 Colorado to Ontario

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Top 5 airlines flying from Colorado to Ontario

Discover the top 5 airlines that operate flights from Colorado to Ontario. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated 2月 24, 2026.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$67Average$164FlexibilityNo cancel feeOn-time62%
United AirlinesCheapest$118Average$371FlexibilityNo cancel feeOn-time69%
SouthwestCheapest$127Average$322FlexibilityNo cancel feeOn-time63%
DeltaCheapest$196Average$288FlexibilityNo cancel feeOn-timeN/A
American AirlinesCheapest$200Average$333FlexibilityNo cancel feeOn-time71%

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