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Denver

$164+ 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 6/15. Fares are subject to change and may not be available on all flights or dates of travel.
YYZ — DEN
May 6 — May 131
Tue 5/6
Tue 5/13
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 May 1, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

eDreams
3 stars

Round-trip from

$275
(Kiwi.com)

One-way from

$164
(Trip.com)

Popular in

December

Cheapest in

October

Average price

$434

Good round-trip deal

$315 or less

Good one-way deal

$185 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 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. 3% potential increase in price ($14 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 May 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 May 1, 2025.

This Kiwi.com deal was found by Cheapflights users on 4/30. 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.
Fri 5/2310:20 pmYYZ - DEN
2 stops15h 07mWestJet
Thu 5/297:40 pmDEN - YYZ
1 stop8h 34mWestJet
Deal found 4/30$275
This Trip.com deal was found by Cheapflights users on 4/30. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/165:30 pmYUL - DEN
1 stop19h 57mWestJet
Tue 7/2212:15 pmDEN - YUL
1 stop10h 28mWestJet
Deal found 4/30$291
This FlightHub deal was found by Cheapflights users on 4/29. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/236:00 amYKF - DEN
1 stop14h 52mWestJet
Fri 5/307:40 pmDEN - YKF
1 stop27h 06mWestJet
Deal found 4/29$295
This Kiwi.com deal was found by Cheapflights users on 4/29. 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.
Sun 5/254:05 pmYTZ - DEN
1 stop17h 57mMultiple Airlines
Sat 5/318:22 pmDEN - YTZ
1 stop14h 00mMultiple Airlines
Deal found 4/29$316
This Kiwi.com deal was found by Cheapflights users on 4/29. 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 6/1912:00 pmYYZ - DEN
2 stops18h 01mMultiple Airlines
Mon 6/2312:15 pmDEN - YYZ
1 stop8h 39mMultiple Airlines
Deal found 4/29$320
This oojo deal was found by Cheapflights users on 4/29. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 8/156:00 amYHM - DEN
1 stop14h 52mWestJet
Mon 8/1812:15 pmDEN - YHM
1 stop10h 26mWestJet
Deal found 4/29$339
This FlightHub deal was found by Cheapflights users on 4/30. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 7/196:10 amYOW - DEN
2 stops31h 17mWestJet
Sun 7/2712:15 pmDEN - YOW
1 stop10h 26mWestJet
Deal found 4/30$340
This Mytrip deal was found by Cheapflights users on 5/1. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/226:00 amYKF - DEN
2 stops12h 38mMultiple Airlines
Wed 5/2812:15 pmDEN - YKF
1 stop10h 31mMultiple Airlines
Deal found 5/1$383
This Kiwi.com deal was found by Cheapflights users on 4/30. 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.
Wed 6/183:10 pmYUL - DEN
2 stops12h 11mMultiple Airlines
Wed 6/2512:15 pmDEN - YUL
1 stop10h 28mMultiple Airlines
Deal found 4/30$387
This Kiwi.com deal was found by Cheapflights users on 4/30. 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.
Wed 6/116:50 pmYOW - DEN
1 stop18h 37mMultiple Airlines
Fri 6/1312:04 amDEN - YOW
1 stop15h 02mMultiple Airlines
Deal found 4/30$403
This Mytrip deal was found by Cheapflights users on 4/30. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 6/137:15 pmYHM - DEN
1 stop18h 12mMultiple Airlines
Sun 6/2912:15 pmDEN - YHM
1 stop10h 26mMultiple Airlines
Deal found 4/30$404
This Booking.com deal was found by Cheapflights users on 5/1. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/226:20 pmYYZ - DEN
Nonstop3h 45mAir Canada
Wed 5/287:45 amDEN - YYZ
Nonstop3h 11mAir Canada
Deal found 5/1$424

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 May 1, 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

TorontoDenver

YYZ - DEN

YYZDEN

Toronto Pearson Intl

Fri 5/23

10:20 pm-11:27 am

2 stops15h 07m

Denver Intl

Thu 5/29

7:40 pm-6:14 am

1 stop8h 34m

$275

MontrealDenver

YUL - DEN

YULDEN

Montreal Pierre Elliott Trudeau Intl

Wed 7/16

5:30 pm-11:27 am

1 stop19h 57m

Denver Intl

Tue 7/22

12:15 pm-12:43 am

1 stop10h 28m

$291

TorontoDenver

YKF - DEN

YKFDEN

Toronto Region of Waterloo Intl

Fri 5/23

6:00 am-6:52 pm

1 stop14h 52m

Denver Intl

Fri 5/30

7:40 pm-12:46 am

1 stop27h 06m

$295

TorontoDenver

YTZ - DEN

YTZDEN

Toronto Island

Sun 5/25

4:05 pm-8:02 am

1 stop17h 57m

Denver Intl

Sat 5/31

8:22 pm-12:22 pm

1 stop14h 00m

$316

TorontoDenver

YYZ - DEN

YYZDEN

Toronto Pearson Intl

Thu 6/19

12:00 pm-4:01 am

2 stops18h 01m

Denver Intl

Mon 6/23

12:15 pm-10:54 pm

1 stop8h 39m

$320

HamiltonDenver

YHM - DEN

YHMDEN

Hamilton

Fri 8/15

6:00 am-6:52 pm

1 stop14h 52m

Denver Intl

Mon 8/18

12:15 pm-12:41 am

1 stop10h 26m

$339

OttawaDenver

YOW - DEN

YOWDEN

Ottawa

Sat 7/19

6:10 am-11:27 am

2 stops31h 17m

Denver Intl

Sun 7/27

12:15 pm-12:41 am

1 stop10h 26m

$340

TorontoDenver

YKF - DEN

YKFDEN

Toronto Region of Waterloo Intl

Thu 5/22

6:00 am-4:38 pm

2 stops12h 38m

Denver Intl

Wed 5/28

12:15 pm-12:46 am

1 stop10h 31m

$383

MontrealDenver

YUL - DEN

YULDEN

Montreal Pierre Elliott Trudeau Intl

Wed 6/18

3:10 pm-1:21 am

2 stops12h 11m

Denver Intl

Wed 6/25

12:15 pm-12:43 am

1 stop10h 28m

$387

OttawaDenver

YOW - DEN

YOWDEN

Ottawa

Wed 6/11

6:50 pm-11:27 am

1 stop18h 37m

Denver Intl

Fri 6/13

12:04 am-5:06 pm

1 stop15h 02m

$403

Flights are sorted by cheapest round-trip flights first.

Deals found on 4/29

Showing 1-10 of 41 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 May 1, 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 May 1, 2025.

The most flights from CAON to DEN are scheduled on a Tuesday (9 on average). You will have fewer flight options on Monday, which is when the least amount of flights are scheduled (8 on average).

Rainfall in Denver by month

Plan your trip to Denver by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in Denver ranges from 0.5 - 2.3 inches per month. May is typically the wettest month, when rainfall can reach 2.3 in. January is typically the driest time to visit Denver when rainfall is around 0.5 in.

Temperature in Denver by month

Plan your trip to Denver by taking into account the average temperature totals by month.

If weather is an important factor for your trip to Denver, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 73.4 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 30.2 F).

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 May 1, 2025.
Read reviews from past customers who have flown Delta, United Airlines and American Airlines from Ontario to Denver. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Delta
8.0
Very good
7,934 reviews

Entertainment

7.9

Overall

8.0

Food

7.3

Comfort

7.9

Crew

8.5

Boarding

8.2

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception
Delta
8.0
Very good
7,934 reviews
Delta
8.0
Very good
7,934 reviews

Entertainment

7.9

Overall

8.0

Food

7.3

Comfort

7.9

Crew

8.5

Boarding

8.2

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception
United Airlines
7.4
Good
8,696 reviews
Delta
8.0
Very good
7,934 reviews

Entertainment

7.9

Overall

8.0

Food

7.3

Comfort

7.9

Crew

8.5

Boarding

8.2

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception
American Airlines
7.2
Good
10,000 reviews
Delta
8.0
Very good
7,934 reviews

Entertainment

7.9

Overall

8.0

Food

7.3

Comfort

7.9

Crew

8.5

Boarding

8.2

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception
WestJet
7.2
Good
2,826 reviews
Delta
8.0
Very good
7,934 reviews

Entertainment

7.9

Overall

8.0

Food

7.3

Comfort

7.9

Crew

8.5

Boarding

8.2

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception
Air Canada
7.0
Good
9,252 reviews
Delta
8.0
Very good
7,934 reviews

Entertainment

7.9

Overall

8.0

Food

7.3

Comfort

7.9

Crew

8.5

Boarding

8.2

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception

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?

    $164 is the cheapest one-way deal found within the past few days, from WestJet. You may also be able to find cheap deals on Sun Country Air and Delta, with prices starting from $197 and $237, 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 Austrian Airlines (60%).

  • 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 $579, our data indicates the cheapest price to be $130. The most popular route (Toronto Pearson Intl - Denver Intl), is priced around $284.

  • 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
Silverthorne
Brighton
Golden
Thornton
Greeley
Frisco
Grand Lake
Broomfield
Central City
Glendale
Copper Mountain
Wheat Ridge
Longmont
Idaho Springs
Limon

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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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Pierre Elliott Trudeau Intl to Denver flights
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Calgary to Aspen flights

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 May 1, 2025.
AirlineCheapestAverageFlexibilityOn-time
United AirlinesCheapest$234Average$469FlexibilityNo cancel feeOn-time69%
Air CanadaCheapest$249Average$481FlexibilityNo cancel feeOn-time67%
American AirlinesCheapest$429Average$517FlexibilityNo cancel feeOn-time71%

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