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$89+ Cheap flights from Colorado to Ontario

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 1/8. Fares are subject to change and may not be available on all flights or dates of travel.
DEN — YYZ
Nov 29 — Dec 61
Sat 11/29
Sat 12/6
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 October 30, 2025.

Most accurate provider

eDreams
3 stars

Most trusted provider

eDreams
3 stars

Round-trip from

$312
(Kiwi.com)

One-way from

$89
(Kiwi.com)

Popular in

November

Cheapest in

March

Average price

$533

Good round-trip deal

$559 or less

Good one-way deal

$338 or less
Provider with most accurate pricing for Denver Intl-Toronto (YTO) flight deals.
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Provider most trusted by Cheapflights users for Denver Intl-Toronto (YTO) 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. 6% potential increase in price ($31 potential increase over avg. RT price).
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Cheapest flight prices on average. 1% potential price decrease ($8 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 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 October 30, 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.
Tue 11/1112:59 amDEN - YYZ
2 stops35h 41mMultiple Airlines
Mon 11/177:55 pmYYZ - DEN
1 stop10h 04mMultiple Airlines
Deal found 10/28$312
This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 12/1211:59 pmDEN - YYZ
1 stop9h 44mMultiple Airlines
Sun 12/148:00 pmYYZ - DEN
1 stop9h 58mMultiple Airlines
Deal found 10/29$314
This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 12/611:59 pmDEN - YYZ
1 stop12h 21mMultiple Airlines
Tue 12/97:15 amYYZ - DEN
1 stop14h 58mMultiple Airlines
Deal found 10/29$316
This Kiwi.com deal was found by Cheapflights users on 10/30. 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 12/166:30 amDEN - YYZ
1 stop11h 25mMultiple Airlines
Mon 1/58:00 pmYYZ - DEN
1 stop9h 58mMultiple Airlines
Deal found 10/30$318
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.
Fri 11/1411:04 amDEN - YYZ
1 stop8h 03mMultiple Airlines
Mon 11/177:55 pmYYZ - DEN
1 stop10h 04mMultiple Airlines
Deal found 10/28$321
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.
Sun 11/1612:16 amDEN - YYZ
2 stops18h 51mMultiple Airlines
Wed 11/194:45 pmYYZ - DEN
1 stop26h 02mMultiple Airlines
Deal found 10/28$322
This Kiwi.com deal was found by Cheapflights users on 10/30. 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 12/166:30 amDEN - YYZ
1 stop11h 25mMultiple Airlines
Tue 1/69:35 amYYZ - DEN
1 stop12h 06mMultiple Airlines
Deal found 10/30$323
This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 12/69:42 amDEN - YTZ
1 stop9h 33mMultiple Airlines
Sun 12/79:15 amYTZ - DEN
1 stop6h 47mMultiple Airlines
Deal found 10/29$324
This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/1711:04 amDEN - YYZ
1 stop8h 03mMultiple Airlines
Tue 11/189:35 amYYZ - DEN
1 stop15h 20mMultiple Airlines
Deal found 10/29$325
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.
Fri 11/1411:04 amDEN - YYZ
1 stop8h 03mMultiple Airlines
Thu 11/208:45 pmYYZ - DEN
2 stops22h 02mMultiple Airlines
Deal found 10/28$326
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.
Fri 11/1411:04 amDEN - YYZ
1 stop8h 03mMultiple Airlines
Fri 11/218:45 pmYYZ - DEN
2 stops22h 02mMultiple Airlines
Deal found 10/28$327
This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/411:59 pmDEN - YYZ
1 stop18h 01mMultiple Airlines
Sun 12/77:15 amYYZ - DEN
2 stops17h 49mMultiple Airlines
Deal found 10/29$328

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 October 30, 2025.
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

DenverMontreal

DEN - YUL

DENYUL

Denver Intl

Tue 2/3

3:14 pm-3:08 pm

1 stop21h 54m

Montreal Pierre Elliott Trudeau Intl

Mon 2/9

3:52 pm-10:49 am

1 stop20h 57m

$339

DenverToronto

DEN - YTZ

DENYTZ

Denver Intl

Fri 11/14

12:16 am-3:27 pm

2 stops13h 11m

Toronto Island

Mon 11/17

9:15 am-11:44 pm

2 stops16h 29m

$358

DenverToronto

DEN - YTZ

DENYTZ

Denver Intl

Fri 12/5

6:00 am-6:57 pm

2 stops10h 57m

Toronto Island

Mon 12/8

9:15 am-2:02 pm

1 stop6h 47m

$366

DenverToronto

DEN - YTZ

DENYTZ

Denver Intl

Fri 12/5

7:45 am-6:57 pm

1 stop9h 12m

Toronto Island

Sun 12/7

9:15 am-2:02 pm

1 stop6h 47m

$368

Colorado SpringsOttawa

COS - YOW

COSYOW

Colorado Springs

Tue 4/7

5:13 pm-1:45 pm

2 stops18h 32m

Ottawa

Wed 4/8

5:25 pm-11:59 pm

2 stops8h 34m

$377

DenverToronto

DEN - YYZ

DENYYZ

Denver Intl

Mon 11/17

6:46 pm-3:35 pm

2 stops18h 49m

Toronto Pearson Intl

Wed 11/19

4:45 pm-7:06 pm

2 stops28h 21m

$383

DenverToronto

DEN - YTZ

DENYTZ

Denver Intl

Sat 12/6

11:00 pm-1:10 pm

2 stops12h 10m

Toronto Island

Mon 12/8

9:15 am-2:02 pm

1 stop6h 47m

$385

DenverOttawa

DEN - YOW

DENYOW

Denver Intl

Fri 12/5

11:59 pm-5:13 pm

1 stop15h 14m

Ottawa

Thu 12/11

9:35 am-3:43 pm

1 stop32h 08m

$388

DenverToronto

DEN - YTZ

DENYTZ

Denver Intl

Thu 11/27

6:22 am-7:50 pm

1 stop11h 28m

Toronto Island

Thu 12/4

8:55 am-4:15 pm

1 stop9h 20m

$389

DenverToronto

DEN - YYZ

DENYYZ

Denver Intl

Tue 11/18

11:31 am-3:35 pm

2 stops26h 04m

Toronto Pearson Intl

Fri 11/21

4:45 pm-11:59 pm

1 stop9h 14m

$408

Flights are sorted by cheapest round-trip flights first.

Deals found on 10/30

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 Region of Ontario?

Currently, June is the cheapest month in which you can book a flight from Colorado to Region of Ontario (average of $129). Flying from Colorado to Region of Ontario in February is currently the most expensive (average of $232). 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 ON?

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 October 30, 2025.

It’s optimal to fly from Colorado to Region of Ontario in the afternoon. By choosing this option you can save up to 23% on the cost of your flight, compared to a flight in the evening.

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

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 October 30, 2025.
See what other customers who have flown with Delta, United Airlines, and WestJet from Colorado to Ontario have to say. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
Delta
7.9
Good
7,993 reviews

Crew

8.5

Boarding

8.2

Comfort

7.9

Entertainment

7.9

Food

7.3

Overall

7.9

Reviews

1 / 20
8.0
Excellent

Matthew,Oct 2025

GSP - ATL

This is always a full flight since it is the connecting route to primary destinations through Atlanta. That said, the crew handles the full load well. Not much more to say, it is a short flight with no in-flight services due to the length.
Delta
7.9
Good
7,993 reviews
Delta
7.9
Good
7,993 reviews

Crew

8.5

Boarding

8.2

Comfort

7.9

Entertainment

7.9

Food

7.3

Overall

7.9

Reviews

1 / 20
8.0
Excellent

Matthew,Oct 2025

GSP - ATL

This is always a full flight since it is the connecting route to primary destinations through Atlanta. That said, the crew handles the full load well. Not much more to say, it is a short flight with no in-flight services due to the length.
United Airlines
7.4
Good
8,998 reviews
Delta
7.9
Good
7,993 reviews

Crew

8.5

Boarding

8.2

Comfort

7.9

Entertainment

7.9

Food

7.3

Overall

7.9

Reviews

1 / 20
8.0
Excellent

Matthew,Oct 2025

GSP - ATL

This is always a full flight since it is the connecting route to primary destinations through Atlanta. That said, the crew handles the full load well. Not much more to say, it is a short flight with no in-flight services due to the length.
WestJet
7.2
Good
3,149 reviews
Delta
7.9
Good
7,993 reviews

Crew

8.5

Boarding

8.2

Comfort

7.9

Entertainment

7.9

Food

7.3

Overall

7.9

Reviews

1 / 20
8.0
Excellent

Matthew,Oct 2025

GSP - ATL

This is always a full flight since it is the connecting route to primary destinations through Atlanta. That said, the crew handles the full load well. Not much more to say, it is a short flight with no in-flight services due to the length.
Air Canada
7.1
Good
10,376 reviews
Delta
7.9
Good
7,993 reviews

Crew

8.5

Boarding

8.2

Comfort

7.9

Entertainment

7.9

Food

7.3

Overall

7.9

Reviews

1 / 20
8.0
Excellent

Matthew,Oct 2025

GSP - ATL

This is always a full flight since it is the connecting route to primary destinations through Atlanta. That said, the crew handles the full load well. Not much more to say, it is a short flight with no in-flight services due to the length.

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.

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

    Departing from Colorado to Region of Ontario will take you 18h 32m. The distance between Colorado and Region of Ontario is about 1545 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 Region of Ontario one-way?

    The cheapest airline one-way is American Airlines, with whom users have recently found tickets for as low as $139. However, be on the lookout for offers from United Airlines and Delta, as they are both options that can get you from Colorado to Region of Ontario for a low price.

  • 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 Region of Ontario?

    Currently, June is the cheapest month in which you can book a flight from Colorado to Region of Ontario (average of $129). Flying from Colorado to Region of Ontario in February is currently the most expensive (average of $232). 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

See prices for flight routes from nearby airports that may be better suited for you.
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Top 4 airlines flying from Colorado to Ontario

Discover the top 4 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 October 30, 2025.
AirlineCheapestAverageFlexibilityOn-time
WestJetCheapest$143Average$303FlexibilityNo cancel feeOn-time60%
DeltaCheapest$144Average$176FlexibilityNo cancel feeOn-timeN/A
United AirlinesCheapest$180Average$515FlexibilityNo cancel feeOn-time69%
Air CanadaCheapest$221Average$528FlexibilityNo cancel feeOn-time67%

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