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Colorado

$177+ 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 9/3. Fares are subject to change and may not be available on all flights or dates of travel.
YYZ — DEN
Aug 6 — Aug 131
Wed 8/6
Wed 8/13
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 August 1, 2025.

Round-trip from

$292
(FlightHub)

One-way from

$177
(Air Canada)

Popular in

February

Cheapest in

August

Average price

$417

Good round-trip deal

$399 or less

Good one-way deal

$260 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. 6% potential increase in price ($28 potential increase over avg. RT price).
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Cheapest flight prices on average. 1% potential price decrease ($6 potential savings vs. average RT price).
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Average for round-trip flights in August 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 August 1, 2025.

This FlightHub deal was found by Cheapflights users on 7/31. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/67:15 pmYOW - DEN
1 stop18h 09mWestJet
Tue 9/1612:15 pmDEN - YOW
1 stop10h 25mWestJet
Deal found 7/31$292
This Air Canada deal was found by Cheapflights users on 7/29. 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 Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 11/235:25 pmYUL - DEN
Nonstop4h 30mAir Canada
Wed 11/268:45 amDEN - YUL
1 stop10h 15mAir Canada
Deal found 7/29$306
This oojo deal was found by Cheapflights users on 7/31. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/286:45 amYUL - DEN
2 stops30h 42mWestJet
Sun 8/3112:15 pmDEN - YUL
1 stop10h 28mWestJet
Deal found 7/31$310
This Air Canada deal was found by Cheapflights users on 7/29. 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 Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/209:25 amYOW - DEN
1 stop12h 05mAir Canada
Tue 8/267:45 amDEN - YOW
1 stop7h 20mAir Canada
Deal found 7/29$314
This Kiwi.com deal was found by Cheapflights users on 7/30. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 9/2110:25 pmYYZ - DEN
1 stop14h 59mWestJet
Tue 9/2312:15 pmDEN - YYZ
1 stop8h 37mWestJet
Deal found 7/30$315
This Kiwi.com deal was found by Cheapflights users on 7/30. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/276:00 amYHM - DEN
1 stop31h 24mMultiple Airlines
Sun 10/512:15 pmDEN - YHM
1 stop31h 04mMultiple Airlines
Deal found 7/30$316
This Booking.com deal was found by Cheapflights users on 7/30. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/266:20 pmYYZ - DEN
Nonstop3h 40mAir Canada
Fri 8/297:45 amDEN - YYZ
Nonstop3h 13mAir Canada
Deal found 7/30$320
This Kiwi.com deal was found by Cheapflights users on 7/29. 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.
Fri 9/57:50 amYTZ - DEN
1 stop12h 36mMultiple Airlines
Mon 9/812:28 pmDEN - YTZ
1 stop5h 34mMultiple Airlines
Deal found 7/29$323
This Delta deal was found by Cheapflights users on 7/29. 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.
Sat 9/206:30 amYYZ - DEN
1 stop5h 04mDelta
Thu 9/2512:45 amDEN - YYZ
1 stop8h 35mDelta
Deal found 7/29$324
This Kiwi.com deal was found by Cheapflights users on 7/30. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/238:00 amYYZ - DEN
2 stops14h 27mMultiple Airlines
Sun 9/2812:15 pmDEN - YYZ
1 stop10h 07mMultiple Airlines
Deal found 7/30$325
This Flightnetwork deal was found by Cheapflights users on 7/30. 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 Flightnetwork is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/2112:25 pmYTZ - DEN
1 stop7h 55mAir Canada
Thu 8/285:40 pmDEN - YTZ
1 stop12h 26mAir Canada
Deal found 7/30$333
This United Airlines deal was found by Cheapflights users on 7/30. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/256:33 amYOW - DEN
1 stop15h 39mUnited Airlines
Sun 8/317:48 amDEN - YOW
1 stop11h 47mUnited Airlines
Deal found 7/30$334

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 August 1, 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

Sat 9/6

7:15 pm-11:24 am

1 stop18h 09m

Denver Intl

Tue 9/16

12:15 pm-12:40 am

1 stop10h 25m

$292

MontrealDenver

YUL - DEN

YULDEN

Montreal Pierre Elliott Trudeau Intl

Sun 11/23

5:25 pm-7:55 pm

Nonstop4h 30m

Denver Intl

Wed 11/26

8:45 am-9:00 pm

1 stop10h 15m

$306

MontrealDenver

YUL - DEN

YULDEN

Montreal Pierre Elliott Trudeau Intl

Thu 8/28

6:45 am-11:27 am

2 stops30h 42m

Denver Intl

Sun 8/31

12:15 pm-12:43 am

1 stop10h 28m

$310

OttawaDenver

YOW - DEN

YOWDEN

Ottawa

Wed 8/20

9:25 am-7:30 pm

1 stop12h 05m

Denver Intl

Tue 8/26

7:45 am-5:05 pm

1 stop7h 20m

$314

TorontoDenver

YYZ - DEN

YYZDEN

Toronto Pearson Intl

Sun 9/21

10:25 pm-11:24 am

1 stop14h 59m

Denver Intl

Tue 9/23

12:15 pm-10:52 pm

1 stop8h 37m

$315

HamiltonDenver

YHM - DEN

YHMDEN

Hamilton

Sat 9/27

6:00 am-11:24 am

1 stop31h 24m

Denver Intl

Sun 10/5

12:15 pm-9:19 pm

1 stop31h 04m

$316

TorontoDenver

YYZ - DEN

YYZDEN

Toronto Pearson Intl

Tue 8/26

6:20 pm-8:00 pm

Nonstop3h 40m

Denver Intl

Fri 8/29

7:45 am-12:58 pm

Nonstop3h 13m

$320

TorontoDenver

YTZ - DEN

YTZDEN

Toronto Island

Fri 9/5

7:50 am-6:26 pm

1 stop12h 36m

Denver Intl

Mon 9/8

12:28 pm-8:02 pm

1 stop5h 34m

$323

TorontoDenver

YYZ - DEN

YYZDEN

Toronto Pearson Intl

Sat 9/20

6:30 am-9:34 am

1 stop5h 04m

Denver Intl

Thu 9/25

12:45 am-11:20 am

1 stop8h 35m

$324

TorontoDenver

YYZ - DEN

YYZDEN

Toronto Pearson Intl

Tue 9/23

8:00 am-8:27 pm

2 stops14h 27m

Denver Intl

Sun 9/28

12:15 pm-12:22 am

1 stop10h 07m

$325

Flights are sorted by cheapest round-trip flights first.

Deals found on 7/29

Showing 1-10 of 57 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 August 1, 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 August 1, 2025.

The most flights from CAON to USCO are scheduled on a Monday (10 on average). You will have fewer flight options on Wednesday, which is when the least amount of flights are scheduled (9 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 August 1, 2025.
Peruse reviews from past customers who have flown with Delta, United Airlines, and American Airlines 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.
Delta
8.0
Very good
7,981 reviews

Crew

8.5

Boarding

8.2

Entertainment

7.9

Food

7.3

Comfort

7.9

Overall

8.0

Reviews

1 / 20
8.0
Excellent

Michael,Jul 2025

AMS - ATL

Overall it was great experience, with the exception of snack food. The food offered in two main meals was just fine but for the mid-flight snack, the only option was a large cookie, too sweet and high sugar content. Snacks at the back of the plane were also mainly sweets. There was one nice baked cheddar option but it quickly ran out.
Delta
8.0
Very good
7,981 reviews
Delta
8.0
Very good
7,981 reviews

Crew

8.5

Boarding

8.2

Entertainment

7.9

Food

7.3

Comfort

7.9

Overall

8.0

Reviews

1 / 20
8.0
Excellent

Michael,Jul 2025

AMS - ATL

Overall it was great experience, with the exception of snack food. The food offered in two main meals was just fine but for the mid-flight snack, the only option was a large cookie, too sweet and high sugar content. Snacks at the back of the plane were also mainly sweets. There was one nice baked cheddar option but it quickly ran out.
United Airlines
7.4
Good
8,900 reviews
Delta
8.0
Very good
7,981 reviews

Crew

8.5

Boarding

8.2

Entertainment

7.9

Food

7.3

Comfort

7.9

Overall

8.0

Reviews

1 / 20
8.0
Excellent

Michael,Jul 2025

AMS - ATL

Overall it was great experience, with the exception of snack food. The food offered in two main meals was just fine but for the mid-flight snack, the only option was a large cookie, too sweet and high sugar content. Snacks at the back of the plane were also mainly sweets. There was one nice baked cheddar option but it quickly ran out.
American Airlines
7.2
Good
10,000 reviews
Delta
8.0
Very good
7,981 reviews

Crew

8.5

Boarding

8.2

Entertainment

7.9

Food

7.3

Comfort

7.9

Overall

8.0

Reviews

1 / 20
8.0
Excellent

Michael,Jul 2025

AMS - ATL

Overall it was great experience, with the exception of snack food. The food offered in two main meals was just fine but for the mid-flight snack, the only option was a large cookie, too sweet and high sugar content. Snacks at the back of the plane were also mainly sweets. There was one nice baked cheddar option but it quickly ran out.
WestJet
7.2
Good
2,978 reviews
Delta
8.0
Very good
7,981 reviews

Crew

8.5

Boarding

8.2

Entertainment

7.9

Food

7.3

Comfort

7.9

Overall

8.0

Reviews

1 / 20
8.0
Excellent

Michael,Jul 2025

AMS - ATL

Overall it was great experience, with the exception of snack food. The food offered in two main meals was just fine but for the mid-flight snack, the only option was a large cookie, too sweet and high sugar content. Snacks at the back of the plane were also mainly sweets. There was one nice baked cheddar option but it quickly ran out.
Air Canada
7.1
Good
9,851 reviews
Delta
8.0
Very good
7,981 reviews

Crew

8.5

Boarding

8.2

Entertainment

7.9

Food

7.3

Comfort

7.9

Overall

8.0

Reviews

1 / 20
8.0
Excellent

Michael,Jul 2025

AMS - ATL

Overall it was great experience, with the exception of snack food. The food offered in two main meals was just fine but for the mid-flight snack, the only option was a large cookie, too sweet and high sugar content. Snacks at the back of the plane were also mainly sweets. There was one nice baked cheddar option but it quickly ran out.

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

    The cheapest airline one-way is Air Canada, with whom users have recently found tickets for as low as $177. However, be on the lookout for offers from WestJet and American Airlines, 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 3 airlines flying from Ontario to Colorado

Discover the top 3 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 August 1, 2025.
AirlineCheapestAverageFlexibilityOn-time
WestJetCheapest$229Average$377FlexibilityNo cancel feeOn-time60%
United AirlinesCheapest$234Average$444FlexibilityNo cancel feeOn-time69%
Air CanadaCheapest$254Average$447FlexibilityNo cancel feeOn-time67%

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