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Colorado

$128+ Cheap flights from Ontario 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 10/20. Fares are subject to change and may not be available on all flights or dates of travel.
YYZ — DEN
Oct 11 — Oct 181
Sat 10/11
Sat 10/18
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 September 11, 2025.

Round-trip from

$268
(United Airlines)

One-way from

$128
(Kiwi.com)

Popular in

December

Cheapest in

August

Average price

$424

Good round-trip deal

$361 or less

Good one-way deal

$245 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. 4% potential increase in price ($20 potential increase over avg. RT price).
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Cheapest flight prices on average. 1% potential price decrease ($5 potential savings vs. average RT price).
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Average for round-trip flights in September 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 September 11, 2025.

This United Airlines deal was found by Cheapflights users on 9/10. 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 10/155:50 pmYOW - DEN
1 stop7h 25mUnited Airlines
Sat 10/257:48 amDEN - YOW
1 stop7h 18mUnited Airlines
Deal found 9/10$268
This Delta deal was found by Cheapflights users on 9/9. 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.
Tue 10/712:36 pmYUL - COS
1 stop9h 54mDelta
Thu 10/236:00 amCOS - YUL
1 stop9h 34mDelta
Deal found 9/9$281
This Kiwi.com deal was found by Cheapflights users on 9/10. 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.
Wed 9/245:30 pmYUL - DEN
1 stop19h 54mMultiple Airlines
Tue 10/77:00 amDEN - YUL
2 stops15h 41mMultiple Airlines
Deal found 9/10$291
This Kiwi.com deal was found by Cheapflights users on 9/10. 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.
Wed 9/245:30 pmYUL - DEN
1 stop19h 54mMultiple Airlines
Wed 10/88:00 amDEN - YUL
2 stops14h 27mMultiple Airlines
Deal found 9/10$297
This Kiwi.com deal was found by Cheapflights users on 9/10. 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.
Wed 9/245:30 pmYUL - DEN
1 stop19h 54mMultiple Airlines
Wed 10/16:01 pmDEN - YUL
2 stops28h 26mMultiple Airlines
Deal found 9/10$299
This Kiwi.com deal was found by Cheapflights users on 9/10. 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.
Thu 10/236:45 amYUL - DEN
1 stop18h 31mMultiple Airlines
Mon 10/277:00 amDEN - YUL
2 stops15h 43mMultiple Airlines
Deal found 9/10$303
This Kiwi.com deal was found by Cheapflights users on 9/10. 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.
Wed 9/245:30 pmYUL - DEN
1 stop19h 54mWestJet
Mon 9/2912:15 pmDEN - YUL
2 stops34h 12mWestJet
Deal found 9/10$304
This eDestinos deal was found by Cheapflights users on 9/10. 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 eDestinos is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/301:30 pmYYZ - DEN
3 stops24h 30mMultiple Airlines
Sat 11/112:16 amDEN - YYZ
1 stop13h 04mMultiple Airlines
Deal found 9/10$308
This Kiwi.com deal was found by Cheapflights users on 9/9. 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.
Sun 9/214:00 pmYYZ - DEN
1 stop18h 16mMultiple Airlines
Fri 10/312:15 pmDEN - YYZ
1 stop10h 07mMultiple Airlines
Deal found 9/9$309
This Kiwi.com deal was found by Cheapflights users on 9/9. 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.
Mon 9/152:00 pmYYZ - DEN
2 stops16h 00mMultiple Airlines
Fri 10/312:15 pmDEN - YYZ
1 stop10h 07mMultiple Airlines
Deal found 9/9$310
This American Airlines deal was found by Cheapflights users on 9/9. 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.
Wed 11/56:00 amYYZ - DEN
1 stop18h 22mAmerican Airlines
Tue 11/117:22 amDEN - YYZ
1 stop12h 07mAmerican Airlines
Deal found 9/9$311
This Kiwi.com deal was found by Cheapflights users on 9/9. 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.
Sun 9/2110:25 pmYYZ - DEN
2 stops38h 31mMultiple Airlines
Wed 10/1510:29 pmDEN - YYZ
1 stop19h 16mMultiple Airlines
Deal found 9/9$312

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 September 11, 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

OttawaDenver

YOW - DEN

YOWDEN

Ottawa

Wed 10/15

5:50 pm-11:15 pm

1 stop7h 25m

Denver Intl

Sat 10/25

7:48 am-5:06 pm

1 stop7h 18m

$268

OttawaDenver

YOW - DEN

YOWDEN

Ottawa

Tue 3/3

7:45 am-5:44 pm

1 stop11h 59m

Denver Intl

Wed 3/4

11:15 am-7:22 pm

1 stop6h 07m

$311

TorontoDenver

YYZ - DEN

YYZDEN

Toronto Pearson Intl

Sun 9/21

10:25 pm-11:24 am

1 stop14h 59m

Denver Intl

Mon 9/29

12:15 pm-10:52 pm

1 stop8h 37m

$323

TorontoDenver

YTZ - DEN

YTZDEN

Toronto Island

Sat 10/25

1:35 pm-8:30 pm

1 stop8h 55m

Denver Intl

Wed 10/29

7:40 am-8:00 pm

1 stop10h 20m

$325

TorontoDenver

YYZ - DEN

YYZDEN

Toronto Pearson Intl

Thu 1/29

8:30 am-10:23 am

Nonstop3h 53m

Denver Intl

Mon 2/2

5:30 pm-10:41 pm

Nonstop3h 11m

$327

TorontoDenver

YTZ - DEN

YTZDEN

Toronto Island

Fri 10/17

1:35 pm-8:30 pm

1 stop8h 55m

Denver Intl

Mon 10/20

6:38 am-5:53 pm

1 stop9h 15m

$329

TorontoDenver

YTZ - DEN

YTZDEN

Toronto Island

Wed 10/1

1:35 pm-3:00 pm

1 stop27h 25m

Denver Intl

Mon 10/6

8:30 pm-12:17 pm

1 stop13h 47m

$330

OttawaDenver

YOW - DEN

YOWDEN

Ottawa

Fri 10/17

5:25 pm-6:42 am

1 stop15h 17m

Denver Intl

Mon 10/20

11:59 pm-1:09 pm

2 stops11h 10m

$333

TorontoDenver

YTZ - DEN

YTZDEN

Toronto Island

Sat 10/4

1:35 pm-8:29 pm

1 stop8h 54m

Denver Intl

Sat 10/11

8:22 pm-12:17 pm

1 stop13h 55m

$335

TorontoDenver

YTZ - DEN

YTZDEN

Toronto Island

Tue 3/3

10:25 am-7:55 pm

2 stops11h 30m

Denver Intl

Wed 3/4

11:15 am-9:28 pm

2 stops8h 13m

$338

Flights are sorted by cheapest round-trip flights first.

Deals found on 9/9

Showing 1-10 of 60 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 Region of Ontario to Colorado?

Currently, October is the cheapest month in which you can book a flight from Region of Ontario to Colorado (average of $197). Flying from Region of 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 ON 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 September 11, 2025.

When flying from Region of Ontario to Colorado, the time of day you decide to fly out makes little to no difference towards the overall price you’ll pay on tickets.

Weekly flight availability from Region of 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 September 11, 2025.

The most flights from CAON to USCO are scheduled on a Monday (11 on average). You will have fewer flight options on Wednesday, which is when the least amount of flights are scheduled (10 on average).

How much does it cost to fly round-trip from Region of Ontario to Colorado?

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 September 11, 2025.
Peruse reviews from past customers who have flown with United Airlines, WestJet, and Air Canada from Ontario to Colorado to help guide your decision. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
United Airlines
7.4
Good
8,937 reviews

Entertainment

7.1

Food

6.6

Overall

7.4

Comfort

7.3

Crew

8.1

Boarding

7.7

Reviews

1 / 20
8.0
Excellent

Anonymous,Dec 2024

YVR - SFO

It was a good experience. The flight took 45 minutes longer to fly and all passengers had to wait inside the plane till the technical issue was fixed. Overall it was a good experience.
United Airlines
7.4
Good
8,937 reviews
United Airlines
7.4
Good
8,937 reviews

Entertainment

7.1

Food

6.6

Overall

7.4

Comfort

7.3

Crew

8.1

Boarding

7.7

Reviews

1 / 20
8.0
Excellent

Anonymous,Dec 2024

YVR - SFO

It was a good experience. The flight took 45 minutes longer to fly and all passengers had to wait inside the plane till the technical issue was fixed. Overall it was a good experience.
WestJet
7.2
Good
3,091 reviews
United Airlines
7.4
Good
8,937 reviews

Entertainment

7.1

Food

6.6

Overall

7.4

Comfort

7.3

Crew

8.1

Boarding

7.7

Reviews

1 / 20
8.0
Excellent

Anonymous,Dec 2024

YVR - SFO

It was a good experience. The flight took 45 minutes longer to fly and all passengers had to wait inside the plane till the technical issue was fixed. Overall it was a good experience.
Air Canada
7.1
Good
10,000 reviews
United Airlines
7.4
Good
8,937 reviews

Entertainment

7.1

Food

6.6

Overall

7.4

Comfort

7.3

Crew

8.1

Boarding

7.7

Reviews

1 / 20
8.0
Excellent

Anonymous,Dec 2024

YVR - SFO

It was a good experience. The flight took 45 minutes longer to fly and all passengers had to wait inside the plane till the technical issue was fixed. Overall it was a good experience.

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.

  • How long is the flight from Region of Ontario to Colorado?

    For as low as $268, United Airlines can have you in Colorado from Region of Ontario in 7h 25m. Region of Ontario and Colorado are separated by a distance of 1513 mi. Both multi-stop and nonstop flights can be found to your destination and back.

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

    The cheapest airline one-way is United Airlines, with whom users have recently found tickets for as low as $163. However, be on the lookout for offers from American Airlines and Delta, as they are both options that can get you from Region of Ontario to Colorado for a low price.

  • 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 Region of Ontario to Colorado?

    Currently, October is the cheapest month in which you can book a flight from Region of Ontario to Colorado (average of $197). Flying from Region of 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 2 airlines flying from Ontario to Colorado

Discover the top 2 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 September 11, 2025.
AirlineCheapestAverageFlexibilityOn-time
Air CanadaCheapest$254Average$443FlexibilityNo cancel feeOn-time67%
United AirlinesCheapest$384Average$590FlexibilityNo cancel feeOn-time69%

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