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$127+ 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 8/24. Fares are subject to change and may not be available on all flights or dates of travel.
DEN — YYZ
Aug 30 — Sep 61
Sun 8/30
Sun 9/6
1 adult, Economy
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Cheap 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 July 31, 2026.

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.
Mon 9/2810:38 am
DEN
-
YYZ
1 stop9h 17m
Multiple Airlines
Tue 9/294:55 pm
YYZ
-
DEN
2 stops30h 08m
Multiple Airlines
Deal found 7/30$341
This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/1010:38 am
DEN
-
YYZ
1 stop9h 17m
Multiple Airlines
Sun 9/204:45 pm
YYZ
-
DEN
1 stop29h 42m
Multiple Airlines
Deal found 7/31$342
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 10/203:10 pm
DEN
-
YTZ
1 stop22h 50m
Multiple Airlines
Sat 10/241:45 pm
YTZ
-
DEN
2 stops21h 46m
Multiple Airlines
Deal found 7/30$343
This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/1010:38 am
DEN
-
YYZ
1 stop9h 17m
Multiple Airlines
Thu 9/177:00 am
YYZ
-
DEN
1 stop10h 00m
Multiple Airlines
Deal found 7/31$343
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.
Thu 9/1010:38 am
DEN
-
YYZ
1 stop9h 17m
Multiple Airlines
Mon 9/214:45 pm
YYZ
-
DEN
1 stop7h 58m
Multiple Airlines
Deal found 7/30$344
This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/108:55 pm
DEN
-
YTZ
1 stop15h 30m
Multiple Airlines
Sat 9/1910:50 am
YTZ
-
DEN
1 stop8h 26m
Multiple Airlines
Deal found 7/31$345
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.
Mon 9/1410:38 am
DEN
-
YYZ
1 stop9h 17m
Multiple Airlines
Tue 9/226:00 am
YYZ
-
DEN
2 stops14h 15m
Multiple Airlines
Deal found 7/30$345
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 9/1110:44 am
DEN
-
YTZ
2 stops24h 11m
Multiple Airlines
Wed 9/1610:50 am
YTZ
-
DEN
1 stop8h 26m
Multiple Airlines
Deal found 7/29$347
This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/2011:59 pm
DEN
-
YTZ
2 stops14h 01m
Multiple Airlines
Fri 10/304:35 pm
YTZ
-
DEN
1 stop9h 54m
Multiple Airlines
Deal found 7/31$351
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 9/157:12 pm
DEN
-
YTZ
2 stops18h 48m
Multiple Airlines
Mon 9/2110:50 am
YTZ
-
DEN
1 stop11h 37m
Multiple Airlines
Deal found 7/30$352
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.
Mon 9/1410:44 am
DEN
-
YTZ
2 stops25h 41m
Multiple Airlines
Mon 9/2110:50 am
YTZ
-
DEN
1 stop11h 37m
Multiple Airlines
Deal found 7/30$353
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.
Mon 9/1410:38 am
DEN
-
YYZ
1 stop9h 17m
Multiple Airlines
Fri 9/188:35 pm
YYZ
-
DEN
1 stop15h 32m
Multiple Airlines
Deal found 7/30$353

Find flight deals from Colorado to Ontario

Keep the following information in mind while searching for Colorado to Ontario flight deals. Data was last updated July 31, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$341
(Kiwi.com)

One-way from

$127
(Kiwi.com)

Popular in

February

Cheapest in

November

Average price

$629

Good round-trip deal

$598 or less

Good one-way deal

$286 or less
Provider with most accurate pricing for Denver Intl-Toronto (YTO) flight deals.
Search Deals
Provider most trusted by Cheapflights users for Denver Intl-Toronto (YTO) flights.
Search Deals
From Colorado to Ontario
Search Deals
One-way flight from Colorado to Ontario
Search Deals
Highest demand for flights based on searches. 8% potential increase in price ($52 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 1% potential price decrease ($9 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in July 2026
Search Deals
Price to beat on a round-trip flight from Colorado to Ontario.
Search Deals
Price to beat on a one-way flight from Colorado to Ontario.
Search Deals

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 July 31, 2026.
Use the filters below to find and compare flights from Colorado to Ontario that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

DenverToronto

DEN - YTZ

DENYTZ

Denver Intl

Thu 9/24

8:55 pm-2:25 pm

1 stop15h 30m

Toronto Island

Wed 9/30

10:50 am-5:16 pm

1 stop8h 26m

$352

DenverToronto

DEN - YTZ

DENYTZ

Denver Intl

Wed 10/14

6:25 am-6:00 pm

1 stop9h 35m

Toronto Island

Sun 10/18

10:50 am-12:44 pm

1 stop27h 54m

$411

DenverLondon

DEN - YXU

DENYXU

Denver Intl

Thu 8/13

12:15 pm-7:50 pm

1 stop29h 35m

London

Mon 8/17

5:55 pm-11:20 am

1 stop19h 25m

$424

DenverToronto

DEN - YTZ

DENYTZ

Denver Intl

Sun 9/27

11:23 am-12:55 pm

1 stop23h 32m

Toronto Island

Thu 10/1

10:50 am-9:49 pm

1 stop12h 59m

$427

DenverToronto

DEN - YTZ

DENYTZ

Denver Intl

Sun 8/30

11:59 pm-5:20 pm

2 stops15h 21m

Toronto Island

Sat 9/5

1:45 pm-11:59 pm

1 stop12h 14m

$438

DenverToronto

DEN - YTZ

DENYTZ

Denver Intl

Thu 10/29

6:55 am-6:15 pm

1 stop9h 20m

Toronto Island

Sun 11/1

1:10 pm-11:00 pm

2 stops11h 50m

$484

DenverHamilton

DEN - YHM

DENYHM

Denver Intl

Tue 8/25

12:15 pm-5:15 pm

1 stop27h 00m

Hamilton

Tue 9/1

6:10 pm-11:20 am

1 stop19h 10m

$498

DenverOttawa

DEN - YOW

DENYOW

Denver Intl

Thu 9/3

11:59 pm-5:23 pm

2 stops15h 24m

Ottawa

Mon 9/7

4:15 pm-8:07 am

1 stop17h 52m

$503

Colorado SpringsMontreal

COS - YUL

COSYUL

Colorado Springs

Tue 10/6

12:46 pm-11:44 am

1 stop20h 58m

Montreal Pierre Elliott Trudeau Intl

Tue 10/13

5:34 pm-12:56 pm

1 stop21h 22m

$513

Colorado SpringsMontreal

COS - YUL

COSYUL

Colorado Springs

Sat 10/31

12:02 pm-9:17 pm

1 stop7h 15m

Montreal Pierre Elliott Trudeau Intl

Tue 11/3

6:00 am-11:15 am

1 stop7h 15m

$514

Flights are sorted by cheapest round-trip flights first.

Deals found on 7/30

Showing 1-10 of 60 resultsSorted by cheapest first
1
2
3
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6

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, October is the cheapest month in which you can book a flight from Colorado to Region of Ontario (average of $501). Flying from Colorado to Region of Ontario in February is currently the most expensive (average of $686). 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 July 31, 2026.

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

Weekly flight availability from Colorado to Region of 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 July 31, 2026.

The most flights from USCO to CAON are scheduled on a Wednesday (10 on average). You will have fewer flight options on Sunday, which is when the least amount of flights are scheduled (4 on average).

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

Airfare is below average for this route at the moment.
Colorado to Region of Ontario flights typically cost between $397 and $632 in September.
The cheapest round-trip price found within the last 5 days was $341 on Multiple Airlines (Sep 28-Sep 29).

How far ahead should I book a flight from Colorado to Region of Ontario?

Booking 23 days in advance of your planned departure date is, on average, the best time to get cheap flights from Colorado to Region of Ontario. The general trend is that the closer you book to the departure date, the more expensive your flight will be.

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 July 31, 2026.
See what other customers who have flown with United Airlines and Air Canada from Colorado to Ontario have to say. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
United Airlines
7.4
Good
10,055 reviews

Crew

8.1

Food

6.7

Overall

7.4

Entertainment

7.1

Boarding

7.7

Comfort

7.3

Reviews

1 / 20
10.0
Excellent

Michelle,Dec 2025

DEN - MKE

I liked that the plane waited 5 minutes for a family whose incoming plane was late. This was the last flight of the day to MKE. Flight attendants actually checked in throughout the flight. Although, not really friendly. Happy to see screens on seat backs again. This is my first time not flying first class in over 10 years. It was economy plus.
United Airlines
7.4
Good
10,055 reviews
United Airlines
7.4
Good
10,055 reviews

Crew

8.1

Food

6.7

Overall

7.4

Entertainment

7.1

Boarding

7.7

Comfort

7.3

Reviews

1 / 20
10.0
Excellent

Michelle,Dec 2025

DEN - MKE

I liked that the plane waited 5 minutes for a family whose incoming plane was late. This was the last flight of the day to MKE. Flight attendants actually checked in throughout the flight. Although, not really friendly. Happy to see screens on seat backs again. This is my first time not flying first class in over 10 years. It was economy plus.
Air Canada
7.1
Good
11,413 reviews
United Airlines
7.4
Good
10,055 reviews

Crew

8.1

Food

6.7

Overall

7.4

Entertainment

7.1

Boarding

7.7

Comfort

7.3

Reviews

1 / 20
10.0
Excellent

Michelle,Dec 2025

DEN - MKE

I liked that the plane waited 5 minutes for a family whose incoming plane was late. This was the last flight of the day to MKE. Flight attendants actually checked in throughout the flight. Although, not really friendly. Happy to see screens on seat backs again. This is my first time not flying first class in over 10 years. It was economy plus.

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 7h 15m. The distance between Colorado and Region of Ontario is about 1639 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 United Airlines, with whom users have recently found tickets for as low as $160. However, be on the lookout for offers from Air Canada 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, October is the cheapest month in which you can book a flight from Colorado to Region of Ontario (average of $501). Flying from Colorado to Region of Ontario in February is currently the most expensive (average of $686). 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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Top 2 airlines flying from Colorado to Ontario

Discover the top 2 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 July 31, 2026.
AirlineCheapestAverageFlexibilityOn-time
Air CanadaCheapest$203Average$661FlexibilityNo cancel feeOn-time67%
United AirlinesCheapest$225Average$661FlexibilityNo cancel feeOn-time69%

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