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$111+ Cheap flights from Denver (DEN) 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 6/4. Fares are subject to change and may not be available on all flights or dates of travel.
DEN — YYZ
May 27 — Jun 31
Wed 5/27
Wed 6/3
1 adult, Economy
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Cheap flight deals from Denver to Ontario

Cheapest flights from Denver to Ontario
Explore the most affordable flight options available from Denver to Ontario. Find the lowest fares from popular airlines and budget airlines, with prices last updated on April 27, 2026.

This Kiwi.com deal was found by Cheapflights users on 4/23. 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 5/1112:15 pm
DEN
-
YYZ
1 stop8h 30m
WestJet
Sun 5/1710:25 pm
YYZ
-
DEN
1 stop14h 55m
WestJet
Deal found 4/23$258
This Kiwi.com deal was found by Cheapflights users on 4/23. 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 5/122:40 pm
DEN
-
YYZ
1 stop29h 15m
Multiple Airlines
Sat 5/235:20 pm
YYZ
-
DEN
2 stops20h 00m
Multiple Airlines
Deal found 4/23$261
This Kiwi.com deal was found by Cheapflights users on 4/23. 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 5/122:40 pm
DEN
-
YYZ
1 stop29h 15m
Multiple Airlines
Sun 5/1710:25 pm
YYZ
-
DEN
1 stop14h 55m
Multiple Airlines
Deal found 4/23$265
This Kiwi.com deal was found by Cheapflights users on 4/23. 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 5/1312:15 pm
DEN
-
YYZ
1 stop8h 30m
Multiple Airlines
Wed 5/206:15 am
YYZ
-
DEN
2 stops19h 54m
Multiple Airlines
Deal found 4/23$268
This Justfly.com deal was found by Cheapflights users on 4/23. 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 Justfly.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/1512:15 pm
DEN
-
YYZ
1 stop9h 55m
WestJet
Mon 5/1810:25 pm
YYZ
-
DEN
1 stop14h 55m
WestJet
Deal found 4/23$277
This Kiwi.com deal was found by Cheapflights users on 4/25. 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 6/212:15 pm
DEN
-
YYZ
1 stop9h 55m
WestJet
Tue 6/910:25 pm
YYZ
-
DEN
1 stop14h 55m
WestJet
Deal found 4/25$282
This Trip.com deal was found by Cheapflights users on 4/23. 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.
Tue 6/912:15 pm
DEN
-
YYZ
1 stop9h 55m
WestJet
Sun 6/146:30 pm
YYZ
-
DEN
1 stop18h 50m
WestJet
Deal found 4/23$285
This Kiwi.com deal was found by Cheapflights users on 4/22. 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 6/212:15 pm
DEN
-
YYZ
1 stop8h 30m
WestJet
Sat 6/610:20 pm
YYZ
-
DEN
2 stops15h 00m
WestJet
Deal found 4/22$287
This Trip.com deal was found by Cheapflights users on 4/22. 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 6/312:15 pm
DEN
-
YYZ
1 stop8h 30m
WestJet
Mon 6/810:25 pm
YYZ
-
DEN
1 stop14h 55m
WestJet
Deal found 4/22$288
This Trip.com deal was found by Cheapflights users on 4/23. 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.
Thu 6/412:15 pm
DEN
-
YYZ
1 stop8h 30m
WestJet
Sun 6/1410:25 pm
YYZ
-
DEN
1 stop14h 55m
WestJet
Deal found 4/23$289
This Justfly.com deal was found by Cheapflights users on 4/23. 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 Justfly.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/1512:15 pm
DEN
-
YYZ
1 stop9h 55m
WestJet
Tue 5/1910:25 pm
YYZ
-
DEN
1 stop14h 55m
WestJet
Deal found 4/23$290
This Trip.com deal was found by Cheapflights users on 4/26. 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.
Fri 6/1912:15 pm
DEN
-
YYZ
1 stop9h 55m
WestJet
Sun 6/2110:25 pm
YYZ
-
DEN
1 stop14h 55m
WestJet
Deal found 4/26$291

Find flight deals from Denver to Ontario

Keep the following information in mind while searching for Denver to Ontario flight deals. Data was last updated April 27, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$258
(Kiwi.com)

One-way from

$111
(Justfly.com)

Popular in

February

Cheapest in

September

Average price

$600

Good round-trip deal

$648 or less

Good one-way deal

$354 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 Denver Intl to Ontario
Search Deals
One-way flight from Denver Intl to Ontario
Search Deals
Highest demand for flights based on searches. 8% potential increase in price ($50 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 1% potential price decrease ($8 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in April 2026
Search Deals
Price to beat on a round-trip flight from Denver Intl to Ontario.
Search Deals
Price to beat on a one-way flight from Denver Intl to Ontario.
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Denver 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 April 27, 2026.
Use the filters below to find and compare flights from Denver to Ontario that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

DenverLondon

DEN - YXU

DENYXU

Denver Intl

Fri 7/31

12:15 pm-5:20 am

1 stop15h 05m

London

Sun 8/9

5:55 pm-11:20 am

1 stop19h 25m

$351

DenverHamilton

DEN - YHM

DENYHM

Denver Intl

Sun 5/17

12:15 pm-5:15 pm

1 stop27h 00m

Hamilton

Tue 5/26

6:10 pm-11:20 am

1 stop19h 10m

$394

DenverHamilton

DEN - YHM

DENYHM

Denver Intl

Sun 5/10

12:15 pm-5:15 pm

1 stop27h 00m

Hamilton

Tue 5/12

6:10 pm-11:20 am

1 stop19h 10m

$420

DenverToronto

DEN - YKF

DENYKF

Denver Intl

Thu 6/4

12:15 pm-7:50 pm

1 stop29h 35m

Toronto Region of Waterloo Intl

Sun 6/7

8:40 pm-11:20 am

1 stop16h 40m

$439

DenverToronto

DEN - YKF

DENYKF

Denver Intl

Sun 6/28

12:15 pm-7:50 pm

1 stop29h 35m

Toronto Region of Waterloo Intl

Fri 7/3

8:40 pm-11:20 am

1 stop16h 40m

$444

DenverToronto

DEN - YKF

DENYKF

Denver Intl

Wed 6/24

12:15 pm-7:50 pm

1 stop29h 35m

Toronto Region of Waterloo Intl

Mon 7/6

8:40 pm-11:20 am

1 stop16h 40m

$456

DenverToronto

DEN - YKF

DENYKF

Denver Intl

Tue 7/21

12:15 pm-7:50 pm

1 stop29h 35m

Toronto Region of Waterloo Intl

Mon 7/27

8:40 pm-11:20 am

1 stop16h 40m

$475

DenverToronto

DEN - YKF

DENYKF

Denver Intl

Wed 7/1

12:15 pm-7:50 pm

1 stop29h 35m

Toronto Region of Waterloo Intl

Mon 7/6

8:40 pm-11:20 am

1 stop16h 40m

$476

DenverToronto

DEN - YKF

DENYKF

Denver Intl

Sun 8/2

12:15 pm-7:50 pm

1 stop29h 35m

Toronto Region of Waterloo Intl

Fri 8/7

8:40 pm-11:20 am

1 stop16h 40m

$479

DenverOttawa

DEN - YOW

DENYOW

Denver Intl

Sun 5/31

6:05 am-5:35 pm

2 stops9h 30m

Ottawa

Sun 6/7

12:25 pm-11:31 pm

2 stops13h 06m

$524

Flights are sorted by cheapest round-trip flights first.

Deals found on 4/22

Showing 1-10 of 60 resultsSorted by cheapest first
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Best time to book a flight from Denver to Ontario

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

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

The best time to book flights from Denver to Region of Ontario is 42 days before your desired departure date. The cost of your flight will likely increase significantly if you book two weeks in advance of your flight.

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

Currently, May is the cheapest month in which you can book a flight from Denver to Region of Ontario (average of $108). Flying from Denver to Region of Ontario in April is currently the most expensive (average of $236). 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 DEN to ON?

Find hourly flight availability from Denver 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 April 27, 2026.

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

Weekly flight availability from Denver to Region of Ontario

Explore weekly flight availability from Denver 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 April 27, 2026.

The most flights from DEN to CAON are scheduled on a Saturday (8 on average). You will have fewer flight options on Thursday, which is when the least amount of flights are scheduled (6 on average).

How much does it cost to fly round-trip from Denver 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 April 27, 2026.
Read reviews from past customers who have flown Delta,United Airlines, andWestJet from Denver to Ontario. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Delta
7.9
Good
8,462 reviews

Boarding

8.1

Entertainment

7.8

Overall

7.9

Crew

8.5

Comfort

7.9

Food

7.2

Reviews

1 / 20
6.0
Good

Jim,Nov 2025

AVL - ATL

The exit row seats without a seat in front are great for leg room but don’t have a fold out entertainment console so you’re forced to use the screen several feet in front of you (there is, at least, a remote). Best to bring a tablet loaded with entertainment or a book.
Delta
7.9
Good
8,462 reviews
Delta
7.9
Good
8,462 reviews

Boarding

8.1

Entertainment

7.8

Overall

7.9

Crew

8.5

Comfort

7.9

Food

7.2

Reviews

1 / 20
6.0
Good

Jim,Nov 2025

AVL - ATL

The exit row seats without a seat in front are great for leg room but don’t have a fold out entertainment console so you’re forced to use the screen several feet in front of you (there is, at least, a remote). Best to bring a tablet loaded with entertainment or a book.
United Airlines
7.4
Good
9,668 reviews
Delta
7.9
Good
8,462 reviews

Boarding

8.1

Entertainment

7.8

Overall

7.9

Crew

8.5

Comfort

7.9

Food

7.2

Reviews

1 / 20
6.0
Good

Jim,Nov 2025

AVL - ATL

The exit row seats without a seat in front are great for leg room but don’t have a fold out entertainment console so you’re forced to use the screen several feet in front of you (there is, at least, a remote). Best to bring a tablet loaded with entertainment or a book.
WestJet
7.2
Good
3,327 reviews
Delta
7.9
Good
8,462 reviews

Boarding

8.1

Entertainment

7.8

Overall

7.9

Crew

8.5

Comfort

7.9

Food

7.2

Reviews

1 / 20
6.0
Good

Jim,Nov 2025

AVL - ATL

The exit row seats without a seat in front are great for leg room but don’t have a fold out entertainment console so you’re forced to use the screen several feet in front of you (there is, at least, a remote). Best to bring a tablet loaded with entertainment or a book.
Air Canada
7.1
Good
10,974 reviews
Delta
7.9
Good
8,462 reviews

Boarding

8.1

Entertainment

7.8

Overall

7.9

Crew

8.5

Comfort

7.9

Food

7.2

Reviews

1 / 20
6.0
Good

Jim,Nov 2025

AVL - ATL

The exit row seats without a seat in front are great for leg room but don’t have a fold out entertainment console so you’re forced to use the screen several feet in front of you (there is, at least, a remote). Best to bring a tablet loaded with entertainment or a book.

Related info for your journey

Find useful and relevant information for your journey from Denver to Ontario. 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 from for flights from Denver to Ontario?

    If you book a flight to Ontario from Denver, you will be flying from Denver Intl, which is the city’s only airport. Denver Intl (DEN) is located 18.5 mi from the center of Denver.

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

    Airlines like WestJet, Delta, and Air Canada fly from Denver to Region of Ontario in about 3h 13m. The time it takes to get you to your destination can typically vary by up to 6h 17m. The distance between Denver and Region of Ontario is about 1312 mi. Both multi-stop and nonstop flights can be found to your destination and back.

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

    $124 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 United Airlines and Delta, with prices starting from $176 and $218, respectively.

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

    The most popular route from Denver to Region of Ontario is Denver Intl - Montreal Pierre Elliott Trudeau Intl. You may also consider Denver Intl - Toronto Pearson Intl or Denver Intl - Toronto Island.

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

    The top 3 most reliable airlines when flying from Denver to Region of Ontario are United Airlines (75%), Air Canada (75%) and Austrian Airlines (61%).

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

    Looking for the cheapest flight from Denver to Region of Ontario? While on average our users pay $1,270, our data indicates the cheapest price to be $257. The most popular route (Denver Intl - Montreal Pierre Elliott Trudeau Intl), is priced around $395.

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

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

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

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

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

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

    Currently, May is the cheapest month in which you can book a flight from Denver to Region of Ontario (average of $108). Flying from Denver to Region of Ontario in April is currently the most expensive (average of $236). 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 3 airlines flying from Denver to Ontario

Discover the top 3 airlines that operate flights from Denver 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 April 27, 2026.
AirlineCheapestAverageFlexibilityOn-time
Air CanadaCheapest$186Average$516FlexibilityNo cancel feeOn-time67%
WestJetCheapest$223Average$358FlexibilityNo cancel feeOn-time60%
United AirlinesCheapest$224Average$547FlexibilityNo cancel feeOn-time69%

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