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Colorado

$146+ 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 1/26. Fares are subject to change and may not be available on all flights or dates of travel.
YYZ — DEN
nov. 28 — dic. 51
vie. 11/28
vie. 12/5
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 octubre 29, 2025.

Most accurate provider

eDreams
3 stars

Most trusted provider

eDreams
3 stars

Round-trip from

$328
(American Airlines)

One-way from

$146
(Kiwi.com)

Popular in

December

Cheapest in

November

Average price

$475

Good round-trip deal

$424 or less

Good one-way deal

$265 or less
Provider with most accurate pricing for Toronto (YTO)-Denver Intl flight deals.
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Provider most trusted by Cheapflights users for Toronto (YTO)-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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Highest demand for flights based on searches. 3% potential increase in price ($15 potential increase over avg. RT price).
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Cheapest flight prices on average. 1% potential price decrease ($9 potential savings vs. average RT price).
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Average for round-trip flights in October 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 octubre 29, 2025.

This Kiwi.com deal was found by Cheapflights users on 10/28. 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.
lun. 12/153:55 pmYOW - DEN
1 stop11h 28mMultiple Airlines
mié. 12/2410:37 pmDEN - YOW
2 stops47h 21mMultiple Airlines
Deal found 10/28$337
This Kiwi.com deal was found by Cheapflights users on 10/28. 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.
mar. 12/95:10 pmYUL - DEN
1 stop27h 59mMultiple Airlines
lun. 12/1511:59 pmDEN - YUL
2 stops17h 45mMultiple Airlines
Deal found 10/28$344
This Kiwi.com deal was found by Cheapflights users on 10/28. 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.
vie. 12/127:55 pmYYZ - DEN
1 stop10h 03mMultiple Airlines
mié. 1/74:25 pmDEN - YYZ
1 stop13h 30mMultiple Airlines
Deal found 10/28$346
This Alaska Airlines deal was found by Cheapflights users on 10/28. 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.
mar. 12/94:45 pmYYZ - DEN
1 stop27h 18mAlaska Airlines
mar. 1/68:22 pmDEN - YYZ
1 stop17h 13mAlaska Airlines
Deal found 10/28$350
This Kiwi.com deal was found by Cheapflights users on 10/28. 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.
dom. 12/148:00 pmYYZ - DEN
1 stop9h 58mMultiple Airlines
mar. 1/611:59 pmDEN - YYZ
1 stop9h 47mMultiple Airlines
Deal found 10/28$351
This Flightnetwork deal was found by Cheapflights users on 10/28. 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.
jue. 11/2012:30 pmYTZ - DEN
1 stop9h 25mAir Canada
mié. 11/2611:15 amDEN - YTZ
1 stop8h 20mAir Canada
Deal found 10/28$352
This Kiwi.com deal was found by Cheapflights users on 10/28. 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.
lun. 11/177:55 pmYYZ - DEN
1 stop10h 04mMultiple Airlines
lun. 11/249:44 amDEN - YYZ
2 stops19h 14mMultiple Airlines
Deal found 10/28$352
This Ticket deal was found by Cheapflights users on 10/29. 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 Ticket is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
jue. 11/207:30 amYUL - DEN
1 stop12h 14mAir Canada
mié. 11/268:45 amDEN - YUL
2 stops12h 24mAir Canada
Deal found 10/29$353
This Kiwi.com deal was found by Cheapflights users on 10/28. 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.
jue. 12/117:55 pmYYZ - DEN
1 stop10h 03mMultiple Airlines
mar. 1/611:59 pmDEN - YYZ
1 stop9h 47mMultiple Airlines
Deal found 10/28$353
This Kiwi.com deal was found by Cheapflights users on 10/27. 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.
mar. 11/2512:40 pmYYZ - DEN
1 stop17h 18mMultiple Airlines
mar. 12/210:50 amDEN - YYZ
2 stops35h 21mMultiple Airlines
Deal found 10/27$354
This Kiwi.com deal was found by Cheapflights users on 10/27. 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.
lun. 12/11:30 pmYYZ - DEN
2 stops16h 28mMultiple Airlines
dom. 12/75:35 pmDEN - YYZ
1 stop10h 45mMultiple Airlines
Deal found 10/27$355
This Kiwi.com deal was found by Cheapflights users on 10/27. 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.
vie. 12/197:55 pmYYZ - DEN
1 stop10h 03mMultiple Airlines
mar. 1/611:59 pmDEN - YYZ
1 stop12h 17mMultiple Airlines
Deal found 10/27$356

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 octubre 29, 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

TorontoDenver

YTZ - DEN

YTZDEN

Toronto Island

jue. 11/20

12:30 pm-7:55 pm

1 stop9h 25m

Denver Intl

mié. 11/26

11:15 am-9:35 pm

1 stop8h 20m

$352

TorontoDenver

YTZ - DEN

YTZDEN

Toronto Island

mié. 11/12

9:15 am-7:59 pm

1 stop12h 44m

Denver Intl

jue. 11/13

12:59 am-6:55 pm

2 stops15h 56m

$359

TorontoDenver

YTZ - DEN

YTZDEN

Toronto Island

vie. 11/14

9:15 am-2:16 pm

1 stop7h 01m

Denver Intl

lun. 11/17

8:05 am-6:57 pm

1 stop8h 52m

$359

TorontoDenver

YTZ - DEN

YTZDEN

Toronto Island

lun. 11/24

9:15 am-5:22 pm

1 stop10h 07m

Denver Intl

lun. 12/1

8:45 pm-1:42 pm

1 stop14h 57m

$361

TorontoDenver

YYZ - DEN

YYZDEN

Toronto Pearson Intl

lun. 12/8

4:45 pm-6:03 pm

1 stop27h 18m

Denver Intl

vie. 1/9

11:49 am-3:35 pm

2 stops25h 46m

$368

TorontoDenver

YYZ - DEN

YYZDEN

Toronto Pearson Intl

lun. 12/8

4:45 pm-11:59 pm

1 stop9h 14m

Denver Intl

mar. 1/6

7:20 am-3:35 pm

2 stops30h 15m

$368

TorontoDenver

YTZ - DEN

YTZDEN

Toronto Island

mar. 12/2

7:40 pm-10:18 am

2 stops16h 38m

Denver Intl

jue. 12/4

8:45 pm-1:42 pm

1 stop14h 57m

$381

TorontoDenver

YTZ - DEN

YTZDEN

Toronto Island

mar. 11/25

12:30 pm-7:55 pm

1 stop9h 25m

Denver Intl

mar. 12/2

11:15 am-7:55 pm

1 stop6h 40m

$388

MontrealDenver

YUL - DEN

YULDEN

Montreal Pierre Elliott Trudeau Intl

lun. 12/8

7:10 am-10:44 pm

2 stops17h 34m

Denver Intl

jue. 12/11

7:05 am-11:59 pm

2 stops14h 54m

$392

TorontoDenver

YYZ - DEN

YYZDEN

Toronto Pearson Intl

vie. 1/9

4:10 pm-6:10 pm

Nonstop4h 00m

Denver Intl

lun. 1/12

5:30 pm-10:41 pm

Nonstop3h 11m

$395

Flights are sorted by cheapest round-trip flights first.

Deals found on 10/27

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, November is the cheapest month in which you can book a flight from Region of Ontario to Colorado (average of $200). Flying from Region of Ontario to Colorado in May is currently the most expensive (average of $295). 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 octubre 29, 2025.

When flying from Region of Ontario to Colorado, the time of day you fly usually plays a role in the price. Save by searching for a flight in the evening, which can drop the price by up to 42% versus a flight in the morning.

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 octubre 29, 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
8,999 reviews

Crew

8.1

Overall

7.4

Comfort

7.3

Food

6.6

Boarding

7.7

Entertainment

7.1

Reviews

1 / 20
8.0
Excellent

Anonymous,Oct 2025

YUL - ORD

Crew and customer service are 5 stars. I had a lot of luggage for a very long trip and they were nothing but helpful and found solutions to every problem. It was my first time flying with United, and they really are the friendly skies. Leg room however, on 2/3 flights was terrible. Same for entertainment: There was only a seat-mounted screen on 1/3 flights. It would have been nice to have on the longest leg of the journey.
United Airlines
7.4
Good
8,999 reviews
United Airlines
7.4
Good
8,999 reviews

Crew

8.1

Overall

7.4

Comfort

7.3

Food

6.6

Boarding

7.7

Entertainment

7.1

Reviews

1 / 20
8.0
Excellent

Anonymous,Oct 2025

YUL - ORD

Crew and customer service are 5 stars. I had a lot of luggage for a very long trip and they were nothing but helpful and found solutions to every problem. It was my first time flying with United, and they really are the friendly skies. Leg room however, on 2/3 flights was terrible. Same for entertainment: There was only a seat-mounted screen on 1/3 flights. It would have been nice to have on the longest leg of the journey.
WestJet
7.2
Good
3,148 reviews
United Airlines
7.4
Good
8,999 reviews

Crew

8.1

Overall

7.4

Comfort

7.3

Food

6.6

Boarding

7.7

Entertainment

7.1

Reviews

1 / 20
8.0
Excellent

Anonymous,Oct 2025

YUL - ORD

Crew and customer service are 5 stars. I had a lot of luggage for a very long trip and they were nothing but helpful and found solutions to every problem. It was my first time flying with United, and they really are the friendly skies. Leg room however, on 2/3 flights was terrible. Same for entertainment: There was only a seat-mounted screen on 1/3 flights. It would have been nice to have on the longest leg of the journey.
Air Canada
7.1
Good
10,372 reviews
United Airlines
7.4
Good
8,999 reviews

Crew

8.1

Overall

7.4

Comfort

7.3

Food

6.6

Boarding

7.7

Entertainment

7.1

Reviews

1 / 20
8.0
Excellent

Anonymous,Oct 2025

YUL - ORD

Crew and customer service are 5 stars. I had a lot of luggage for a very long trip and they were nothing but helpful and found solutions to every problem. It was my first time flying with United, and they really are the friendly skies. Leg room however, on 2/3 flights was terrible. Same for entertainment: There was only a seat-mounted screen on 1/3 flights. It would have been nice to have on the longest leg of the journey.

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 $352, Air Canada can have you in Colorado from Region of Ontario in 9h 25m. Region of Ontario and Colorado are separated by a distance of 1322 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 American Airlines, with whom users have recently found tickets for as low as $230. However, be on the lookout for offers from United Airlines and WestJet, 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, November is the cheapest month in which you can book a flight from Region of Ontario to Colorado (average of $200). Flying from Region of Ontario to Colorado in May is currently the most expensive (average of $295). 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 octubre 29, 2025.
AirlineCheapestAverageFlexibilityOn-time
United AirlinesCheapest$251Average$514FlexibilityNo cancel feeOn-time69%
Air CanadaCheapest$267Average$524FlexibilityNo cancel feeOn-time67%

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