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$48+ 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 2/26. Fares are subject to change and may not be available on all flights or dates of travel.
DEN — ONT
feb. 25 — mar. 41
mar. 2/25
mar. 3/4
1 adult, Economy
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Cheap flight deals from Colorado to Ontario

Keep the following information in mind while searching for Colorado to Ontario flight deals. Data was last updated febrero 20, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$59
(Frontier)

One-way from

$48
(Flightnetwork)

Popular in

March

Cheapest in

September

Average price

$187

Good round-trip deal

$85 or less

Good one-way deal

$44 or less
Provider with most accurate pricing for Denver Intl-Los Angeles flight deals.
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Provider most trusted by Cheapflights users for Denver Intl-Los Angeles flights.
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From Colorado to Ontario
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One-way flight from Colorado to Ontario
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Highest demand for flights based on searches. 9% potential increase in price ($19 potential increase over avg. RT price).
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Cheapest flight prices on average. 3% potential price decrease ($7 potential savings vs. average RT price).
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Average for round-trip flights in February 2025
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Price to beat on a round-trip flight from Colorado to Ontario.
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Price to beat on a one-way flight from Colorado to Ontario.
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Find 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 febrero 20, 2025.

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.
mié. 3/1210:32 pmDEN - ONT
Nonstop2h 32mFrontier
dom. 3/1612:59 amONT - DEN
Nonstop2h 17mFrontier
Deal found 2/20$62
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.
jue. 2/273:07 pmEGE - ONT
1 stop10h 02mFrontier
sáb. 3/812:59 amONT - EGE
1 stop11h 08mFrontier
Deal found 2/20$69
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.
vie. 4/118:00 amDEN - ONT
Nonstop2h 20mSouthwest
jue. 4/243:55 pmONT - DEN
1 stop3h 50mSouthwest
Deal found 2/20$127
This Travelocity 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 Travelocity is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lun. 3/1010:37 pmDEN - ONT
Nonstop2h 32mMultiple Airlines
lun. 3/177:00 amONT - DEN
1 stop5h 54mMultiple Airlines
Deal found 2/20$142
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.
mar. 4/87:19 pmDEN - ONT
Nonstop2h 23mUnited Airlines
dom. 4/135:00 amONT - DEN
Nonstop2h 19mUnited Airlines
Deal found 2/20$158
This American 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mar. 4/298:09 amDEN - ONT
1 stop4h 50mAmerican Airlines
mié. 4/304:35 pmONT - DEN
1 stop4h 13mAmerican Airlines
Deal found 2/20$199
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.
jue. 3/68:25 amDEN - ONT
1 stop4h 59mDelta
lun. 3/106:00 amONT - DEN
1 stop6h 03mDelta
Deal found 2/20$216
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.
jue. 5/85:56 amGJT - ONT
1 stop4h 09mDelta
dom. 5/116:00 amONT - GJT
1 stop5h 30mDelta
Deal found 2/20$289
This American Airlines deal was found by Cheapflights users on 2/19. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
sáb. 3/154:40 pmCOS - ONT
1 stop6h 47mAmerican Airlines
lun. 3/1711:59 pmONT - COS
1 stop8h 53mAmerican Airlines
Deal found 2/19$308
This American 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
vie. 3/73:21 pmGJT - ONT
1 stop4h 15mAmerican Airlines
lun. 3/109:32 amONT - GJT
2 stops10h 46mAmerican Airlines
Deal found 2/20$314
This American 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
vie. 3/74:38 pmASE - ONT
1 stop6h 53mAmerican Airlines
lun. 3/106:00 amONT - ASE
1 stop9h 13mAmerican Airlines
Deal found 2/20$349
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.
mié. 4/27:05 amGJT - ONT
1 stop6h 33mUnited Airlines
mar. 4/81:35 pmONT - GJT
1 stop5h 41mUnited Airlines
Deal found 2/20$360

Find flights from Colorado to Ontario within your budget

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 febrero 20, 2025.

Fly from

Colorado

Fly to

Ontario

Route

Depart

Return

Price

DenverOntario

DEN - ONT

DENONT

Denver Intl

mié. 3/12

10:32 pm-12:04 am

Nonstop2h 32m

Ontario

dom. 3/16

12:59 am-4:16 am

Nonstop2h 17m

$62

VailOntario

EGE - ONT

EGEONT

Vail Eagle County

dom. 3/2

3:07 pm-10:25 am

1 stop20h 18m

Ontario

sáb. 3/8

12:59 am-1:07 pm

1 stop11h 08m

$88

DenverOntario

DEN - ONT

DENONT

Denver Intl

vie. 4/11

8:00 am-9:20 am

Nonstop2h 20m

Ontario

jue. 4/24

3:55 pm-8:45 pm

1 stop3h 50m

$127

DenverOntario

DEN - ONT

DENONT

Denver Intl

lun. 3/10

10:37 pm-12:09 am

Nonstop2h 32m

Ontario

lun. 3/17

7:00 am-1:54 pm

1 stop5h 54m

$142

DenverOntario

DEN - ONT

DENONT

Denver Intl

mar. 4/8

7:19 pm-8:42 pm

Nonstop2h 23m

Ontario

dom. 4/13

5:00 am-8:19 am

Nonstop2h 19m

$158

DenverOntario

DEN - ONT

DENONT

Denver Intl

mar. 4/29

8:09 am-11:59 am

1 stop4h 50m

Ontario

mié. 4/30

4:35 pm-9:48 pm

1 stop4h 13m

$199

DenverOntario

DEN - ONT

DENONT

Denver Intl

jue. 3/6

8:25 am-12:24 pm

1 stop4h 59m

Ontario

lun. 3/10

6:00 am-1:03 pm

1 stop6h 03m

$216

Grand JunctionOntario

GJT - ONT

GJTONT

Grand Junction Regnl

jue. 5/8

5:56 am-9:05 am

1 stop4h 09m

Ontario

dom. 5/11

6:00 am-12:30 pm

1 stop5h 30m

$289

Colorado SpringsOntario

COS - ONT

COSONT

Colorado Springs

sáb. 3/15

4:40 pm-10:27 pm

1 stop6h 47m

Ontario

lun. 3/17

11:59 pm-9:52 am

1 stop8h 53m

$308

Grand JunctionOntario

GJT - ONT

GJTONT

Grand Junction Regnl

vie. 3/7

3:21 pm-6:36 pm

1 stop4h 15m

Ontario

lun. 3/10

9:32 am-9:18 pm

2 stops10h 46m

$314

Flights are sorted by cheapest round-trip flights first.

Deals found on 2/20

Showing 1-10 of 41 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.

Travel insights for flights from Colorado to Ontario

Get recent, data-driven insights about flights from Colorado to Ontario including ideal travel times, pricing trends, and more.

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

Currently, August is the cheapest month in which you can book a flight from Colorado to Ontario (average of $246). Flying from Colorado to Ontario in March is currently the most expensive (average of $315). 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 febrero 20, 2025.

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

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 febrero 20, 2025.

The most flights from USCO to ONT are scheduled on a Thursday (11 on average). You will have fewer flight options on Friday, which is when the least amount of flights are scheduled (4 on average).

Rainfall in Ontario by month

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

In terms of precipitation, rainfall in Ontario ranges from 0.1 - 3.4 inches per month. February is typically the wettest month, when rainfall can reach 3.4 in. June is typically the driest time to visit Ontario when rainfall is around 0.1 in.

Temperature in Ontario by month

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

If weather is an important factor for your trip to Ontario, use this chart to help with planning. For those seeking warmer temperatures, August is the ideal time of year to visit, when temperatures reach an average of 78.8 F. Travelers looking to avoid the cold should look outside of December, when temperatures are typically at their lowest (around 53.6 F).

Reviews of airlines servicing Ontario

Get insights into the airlines that provide service to Ontario. 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 Ontario. Reviews last updated febrero 20, 2025.
Get a feel of what it's like to fly with Southwest, Alaska Airlines and Delta from Colorado to Ontario by reading reviews from past customers. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.1
Very good
4,411 reviews

Crew

8.7

Comfort

8.1

Entertainment

7.6

Overall

8.1

Boarding

8.2

Food

7.1

Reviews

1 / 20

8.0
Excellent

Christine,Aug 2024

DEN - LGB

No issues. I needed pre boarding and I was able to get it without issue

Southwest
8.1
Very good
4,411 reviews
Southwest
8.1
Very good
4,411 reviews

Crew

8.7

Comfort

8.1

Entertainment

7.6

Overall

8.1

Boarding

8.2

Food

7.1

Reviews

1 / 20

8.0
Excellent

Christine,Aug 2024

DEN - LGB

No issues. I needed pre boarding and I was able to get it without issue

Alaska Airlines
8.0
Very good
9,692 reviews
Southwest
8.1
Very good
4,411 reviews

Crew

8.7

Comfort

8.1

Entertainment

7.6

Overall

8.1

Boarding

8.2

Food

7.1

Reviews

1 / 20

8.0
Excellent

Christine,Aug 2024

DEN - LGB

No issues. I needed pre boarding and I was able to get it without issue

Delta
8.0
Very good
8,220 reviews
Southwest
8.1
Very good
4,411 reviews

Crew

8.7

Comfort

8.1

Entertainment

7.6

Overall

8.1

Boarding

8.2

Food

7.1

Reviews

1 / 20

8.0
Excellent

Christine,Aug 2024

DEN - LGB

No issues. I needed pre boarding and I was able to get it without issue

Hawaiian Airlines
7.9
Good
2,317 reviews
Southwest
8.1
Very good
4,411 reviews

Crew

8.7

Comfort

8.1

Entertainment

7.6

Overall

8.1

Boarding

8.2

Food

7.1

Reviews

1 / 20

8.0
Excellent

Christine,Aug 2024

DEN - LGB

No issues. I needed pre boarding and I was able to get it without issue

United Airlines
7.4
Good
8,766 reviews
Southwest
8.1
Very good
4,411 reviews

Crew

8.7

Comfort

8.1

Entertainment

7.6

Overall

8.1

Boarding

8.2

Food

7.1

Reviews

1 / 20

8.0
Excellent

Christine,Aug 2024

DEN - LGB

No issues. I needed pre boarding and I was able to get it without issue

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 92 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 Colorado to Ontario one-way?

    The cheapest airlines for a one-way flight from Colorado to Ontario are Frontier ($48), Southwest ($74), and Hawaiian Airlines ($77).

  • 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 (86%), Air Canada (81%) or Frontier (79%) 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 $111, our data shows the cheapest flight currently is $26. When looking at the most popular route, (Denver Intl - Ontario), you can expect to pay $43 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, August is the cheapest month in which you can book a flight from Colorado to Ontario (average of $246). Flying from Colorado to Ontario in March is currently the most expensive (average of $315). 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 Colorado to Ontario

See prices for flight routes from nearby airports that may be better suited for you.
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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 febrero 20, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$47Average$120FlexibilityNo cancel feeOn-time62%
United AirlinesCheapest$141Average$401FlexibilityNo cancel feeOn-time69%
SouthwestCheapest$178Average$331FlexibilityNo cancel feeOn-time63%
American AirlinesCheapest$278Average$393FlexibilityNo cancel feeOn-time71%
DeltaCheapest$287Average$368FlexibilityNo cancel feeOn-timeN/A
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