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Denver

$154+ Cheap flights from Ontario to Denver (DEN)

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
jul 8 — jul 151
ter 7/8
ter 7/15
1 adult, Economy
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Cheap flight deals from Ontario to Denver

Keep the following information in mind while searching for Ontario to Denver flight deals. Data was last updated julho 3, 2025.

Round-trip from

$282
(flugladen.de)

One-way from

$154
(Kiwi.com)

Popular in

December

Cheapest in

August

Average price

$449

Good round-trip deal

$394 or less

Good one-way deal

$225 or less
From Ontario to Denver Intl
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One-way flight from Ontario to Denver Intl
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Highest demand for flights based on searches. 4% potential increase in price ($19 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 July 2025
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Price to beat on a round-trip flight from Ontario to Denver Intl.
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Price to beat on a one-way flight from Ontario to Denver Intl.
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Find flight deals from Ontario to Denver

Cheapest flights from Ontario to Denver
Explore the most affordable flight options available from Ontario to Denver. Find the lowest fares from popular airlines and budget airlines, with prices last updated on julho 3, 2025.

This flugladen.de deal was found by Cheapflights users on 7/1. 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 flugladen.de is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
sex 8/156:00 amYOW - DEN
1 stop6h 21mAir Canada
sex 8/227:45 amDEN - YOW
1 stop7h 20mAir Canada
Deal found 7/1$282
This FlightHub deal was found by Cheapflights users on 7/2. 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.
qui 8/147:15 pmYOW - DEN
1 stop18h 12mWestJet
ter 9/912:15 pmDEN - YOW
1 stop10h 25mWestJet
Deal found 7/2$312
This United Airlines deal was found by Cheapflights users on 7/2. 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.
qui 7/105:25 pmYOW - DEN
1 stop7h 57mUnited Airlines
qui 8/711:54 pmDEN - YOW
1 stop7h 17mUnited Airlines
Deal found 7/2$316
This oojo deal was found by Cheapflights users on 7/1. 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.
qua 8/68:00 pmYYZ - DEN
1 stop17h 27mWestJet
sáb 8/912:15 pmDEN - YYZ
1 stop10h 09mWestJet
Deal found 7/1$324
This Kiwi.com deal was found by Cheapflights users on 7/1. 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.
sex 8/17:55 amYTZ - DEN
1 stop8h 24mMultiple Airlines
seg 8/48:15 amDEN - YTZ
1 stop9h 47mMultiple Airlines
Deal found 7/1$326
This oojo deal was found by Cheapflights users on 7/3. 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.
ter 8/197:45 pmYKF - DEN
1 stop17h 42mWestJet
sex 8/2212:15 pmDEN - YKF
1 stop10h 31mWestJet
Deal found 7/3$328
This Kiwi.com deal was found by Cheapflights users on 7/2. 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.
sex 8/1511:00 amYYZ - DEN
1 stop14h 56mMultiple Airlines
sáb 8/1611:58 pmDEN - YYZ
1 stop12h 31mMultiple Airlines
Deal found 7/2$329
This Air Canada deal was found by Cheapflights users on 7/2. 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.
qui 9/411:00 amYYZ - DEN
1 stop9h 18mAir Canada
seg 9/87:45 amDEN - YYZ
Nonstop3h 05mAir Canada
Deal found 7/2$330
This Mytrip deal was found by Cheapflights users on 7/3. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
qui 8/1412:25 pmYTZ - DEN
1 stop7h 55mAir Canada
qua 8/209:40 amDEN - YTZ
1 stop9h 51mAir Canada
Deal found 7/3$334
This Delta deal was found by Cheapflights users on 7/3. 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.
qua 8/67:24 pmYYZ - DEN
1 stop6h 04mDelta
dom 8/1012:55 amDEN - YYZ
1 stop6h 27mDelta
Deal found 7/3$339
This American Airlines deal was found by Cheapflights users on 7/3. 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.
sex 8/15:15 pmYYZ - DEN
1 stop7h 25mAmerican Airlines
sex 8/87:02 amDEN - YYZ
1 stop5h 52mAmerican Airlines
Deal found 7/3$348
This Air Canada deal was found by Cheapflights users on 7/3. 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.
seg 11/105:25 pmYUL - DEN
Nonstop4h 30mAir Canada
sex 11/148:45 amDEN - YUL
1 stop10h 15mAir Canada
Deal found 7/3$374

Cheapflights Fare Finder

Customize your flight search to find flights from Ontario to Denver 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 julho 3, 2025.
Use the filters below to find and compare flights from Ontario to Denver that are best for you.

Fly from

Ontario

Fly to

Denver

Route

Depart

Return

Price

OttawaDenver

YOW - DEN

YOWDEN

Ottawa

sex 8/15

6:00 am-10:21 am

1 stop6h 21m

Denver Intl

sex 8/22

7:45 am-5:05 pm

1 stop7h 20m

$282

OttawaDenver

YOW - DEN

YOWDEN

Ottawa

qui 8/14

7:15 pm-11:27 am

1 stop18h 12m

Denver Intl

ter 9/9

12:15 pm-12:40 am

1 stop10h 25m

$312

TorontoDenver

YYZ - DEN

YYZDEN

Toronto Pearson Intl

qua 8/6

8:00 pm-11:27 am

1 stop17h 27m

Denver Intl

sáb 8/9

12:15 pm-12:24 am

1 stop10h 09m

$324

TorontoDenver

YTZ - DEN

YTZDEN

Toronto Island

sex 8/1

7:55 am-2:19 pm

1 stop8h 24m

Denver Intl

seg 8/4

8:15 am-8:02 pm

1 stop9h 47m

$326

OttawaDenver

YOW - DEN

YOWDEN

Ottawa

qui 8/14

7:29 pm-12:30 am

1 stop7h 01m

Denver Intl

ter 9/9

11:18 am-9:35 pm

1 stop8h 17m

$326

TorontoDenver

YKF - DEN

YKFDEN

Toronto Region of Waterloo Intl

ter 8/19

7:45 pm-11:27 am

1 stop17h 42m

Denver Intl

sex 8/22

12:15 pm-12:46 am

1 stop10h 31m

$328

TorontoDenver

YYZ - DEN

YYZDEN

Toronto Pearson Intl

sex 8/15

11:00 am-11:56 pm

1 stop14h 56m

Denver Intl

sáb 8/16

11:58 pm-2:29 pm

1 stop12h 31m

$329

TorontoDenver

YYZ - DEN

YYZDEN

Toronto Pearson Intl

qui 9/4

11:00 am-6:18 pm

1 stop9h 18m

Denver Intl

seg 9/8

7:45 am-12:50 pm

Nonstop3h 05m

$330

TorontoDenver

YTZ - DEN

YTZDEN

Toronto Island

qui 8/14

12:25 pm-6:20 pm

1 stop7h 55m

Denver Intl

qua 8/20

9:40 am-9:31 pm

1 stop9h 51m

$334

TorontoDenver

YYZ - DEN

YYZDEN

Toronto Pearson Intl

qua 8/6

5:45 pm-10:11 pm

1 stop6h 26m

Denver Intl

sex 8/8

12:55 am-8:55 am

1 stop6h 00m

$339

Flights are sorted by cheapest round-trip flights first.

Deals found on 7/1

Showing 1-10 of 42 results
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Best time to book a flight from Ontario to Denver

Have a flexible travel schedule? Discover the best time to fly to Denver 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 Denver

What is the cheapest month to book a flight from Region of Ontario to Denver?

Currently, October is the cheapest month in which you can book a flight from Region of Ontario to Denver (average of $197). Flying from Region of Ontario to Denver 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 DEN?

Find hourly flight availability from Ontario to Denver. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated julho 3, 2025.

When flying from Region of Ontario to Denver, 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 Denver

Explore weekly flight availability from Ontario to Denver. 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 julho 3, 2025.

The most flights from CAON to DEN 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 Denver

Get insights into the airlines that provide service to Denver. 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 Denver. Reviews last updated julho 3, 2025.
Peruse reviews from past customers who have flown with Delta, United Airlines, and American Airlines from Ontario to Denver to help guide your decision. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
Delta
8.0
Very good
7,982 reviews

Boarding

8.2

Food

7.3

Crew

8.5

Comfort

7.9

Entertainment

7.9

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!
Delta
8.0
Very good
7,982 reviews
Delta
8.0
Very good
7,982 reviews

Boarding

8.2

Food

7.3

Crew

8.5

Comfort

7.9

Entertainment

7.9

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!
United Airlines
7.4
Good
8,861 reviews
Delta
8.0
Very good
7,982 reviews

Boarding

8.2

Food

7.3

Crew

8.5

Comfort

7.9

Entertainment

7.9

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!
American Airlines
7.2
Good
10,000 reviews
Delta
8.0
Very good
7,982 reviews

Boarding

8.2

Food

7.3

Crew

8.5

Comfort

7.9

Entertainment

7.9

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!
WestJet
7.2
Good
2,917 reviews
Delta
8.0
Very good
7,982 reviews

Boarding

8.2

Food

7.3

Crew

8.5

Comfort

7.9

Entertainment

7.9

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!
Air Canada
7.1
Good
9,681 reviews
Delta
8.0
Very good
7,982 reviews

Boarding

8.2

Food

7.3

Crew

8.5

Comfort

7.9

Entertainment

7.9

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!

Related info for your journey

Find useful and relevant information for your journey from Ontario to Denver. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • What airport do you fly into for flights to Denver from Ontario?

    For a flight from Ontario to Denver, you will be flying into Denver Intl. Denver Intl (DEN) is just 18.5 mi from the center of the city.

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

    $169 is the cheapest one-way deal found within the past few days, from Air Canada. You may also be able to find cheap deals on WestJet and United Airlines, with prices starting from $178 and $184, respectively.

  • What are the most popular routes from Region of Ontario to Denver?

    While some choose either Montreal Pierre Elliott Trudeau Intl - Denver Intl or Toronto Island - Denver Intl, Toronto Pearson Intl - Denver Intl is the most popular route from Region of Ontario to Denver.

  • What are the most reliable airlines from Region of Ontario to Denver?

    The top 3 most reliable airlines when flying from Region of Ontario to Denver are Air Canada (68%), United Airlines (68%) and Brussels Airlines (43%).

  • What are the cheapest flights from Region of Ontario to Denver?

    Looking for the cheapest flight from Region of Ontario to Denver? While on average our users pay $712, our data indicates the cheapest price to be $171. The most popular route (Toronto Pearson Intl - Denver Intl), is priced around $323.

  • Can I find deals for flights from Ontario to Denver that include hotel bookings?

    Yes. In addition to deals on Ontario to Denver flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Ontario to Denver?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Ontario to Denver.

  • Can I find deals for business class flights from Ontario to Denver?

    Yes. Cheapflights offers flight deals from Ontario to Denver 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 Denver?

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

Traveling to a place near Ontario?

Book flights to Ontario if you plan to visit one of these locations
Westminster
Black Hawk
Winter Park
Lakewood
Cripple Creek
Golden
Brighton
Silverthorne
Thornton
Frisco
Broomfield
Grand Lake
Manitou Springs
Central City
Fort Morgan
Glendale
Copper Mountain
Wheat Ridge
Longmont
Idaho Springs

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Alternative routes for Ontario to Denver

See prices for flight routes from nearby airports that may be better suited for you.
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Pearson Intl to Denver flights
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Pierre Elliott Trudeau Intl to Denver flights
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Top 3 airlines flying from Ontario to Denver

Discover the top 3 airlines that operate flights from Ontario to Denver. 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 julho 3, 2025.
AirlineCheapestAverageFlexibilityOn-time
WestJetCheapest$229Average$377FlexibilityNo cancel feeOn-time60%
United AirlinesCheapest$234Average$450FlexibilityNo cancel feeOn-time69%
Air CanadaCheapest$254Average$472FlexibilityNo cancel feeOn-time67%

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