HomeSearch by dateVacation packagesHotelsFlight dealsCar rentalTravel tips & news
Ontario

$100+ 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 10/22. Fares are subject to change and may not be available on all flights or dates of travel.
DEN — YYZ
oct. 16 — oct. 231
jue. 10/16
jue. 10/23
1 adult, Economy
We work with more than 300 partners to bring you better travel deals

Find cheap flights from Denver to Ontario with Cheapflights

1. Tell us where you want to go

Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”

2. Select your favorite providers

We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.

3. Compare prices and book

Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.

Cheap flight deals from Denver to Ontario

Keep the following information in mind while searching for Denver to Ontario flight deals. Data was last updated septiembre 16, 2025.

Round-trip from

$217
(Kiwi.com)

One-way from

$100
(Trip.com)

Popular in

February

Cheapest in

March

Average price

$478

Good round-trip deal

$481 or less

Good one-way deal

$215 or less
From Denver Intl to Ontario
Search Deals
One-way flight from Denver Intl to Ontario
Search Deals
High demand for flights, 26% potential price rise
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 September 2025
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

Find 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 septiembre 16, 2025.

This Kiwi.com deal was found by Cheapflights users on 9/15. 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.
mié. 10/228:21 pmDEN - YYZ
1 stop22h 46mMultiple Airlines
dom. 10/264:00 pmYYZ - DEN
1 stop18h 12mMultiple Airlines
Deal found 9/15$217
This Kiwi.com deal was found by Cheapflights users on 9/15. 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.
mié. 10/158:21 pmDEN - YYZ
1 stop22h 46mMultiple Airlines
mié. 10/229:45 amYYZ - DEN
1 stop15h 25mMultiple Airlines
Deal found 9/15$221
This Kiwi.com deal was found by Cheapflights users on 9/15. 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.
mié. 10/228:21 pmDEN - YYZ
1 stop22h 46mMultiple Airlines
vie. 10/248:05 pmYYZ - DEN
1 stop9h 54mMultiple Airlines
Deal found 9/15$226
This Kiwi.com deal was found by Cheapflights users on 9/15. 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.
mar. 10/1410:29 pmDEN - YYZ
2 stops22h 23mMultiple Airlines
lun. 10/204:00 pmYYZ - DEN
1 stop18h 12mMultiple Airlines
Deal found 9/15$229
This Kiwi.com deal was found by Cheapflights users on 9/15. 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.
mié. 10/228:21 pmDEN - YYZ
1 stop22h 46mMultiple Airlines
mar. 10/281:30 pmYYZ - DEN
2 stops16h 29mMultiple Airlines
Deal found 9/15$232
This Kiwi.com deal was found by Cheapflights users on 9/15. 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.
vie. 10/247:00 amDEN - YYZ
1 stop12h 07mMultiple Airlines
mié. 10/2912:30 pmYYZ - DEN
2 stops17h 29mMultiple Airlines
Deal found 9/15$234
This Kiwi.com deal was found by Cheapflights users on 9/15. 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.
vie. 10/247:00 amDEN - YYZ
1 stop12h 07mMultiple Airlines
jue. 10/309:45 amYYZ - DEN
1 stop10h 48mMultiple Airlines
Deal found 9/15$237
This Kiwi.com deal was found by Cheapflights users on 9/15. 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.
mar. 10/217:00 amDEN - YYZ
2 stops13h 52mMultiple Airlines
dom. 10/264:00 pmYYZ - DEN
1 stop18h 12mMultiple Airlines
Deal found 9/15$239
This Kiwi.com deal was found by Cheapflights users on 9/15. 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.
vie. 10/319:05 amDEN - YYZ
1 stop8h 55mMultiple Airlines
dom. 11/28:00 pmYYZ - DEN
1 stop29h 16mMultiple Airlines
Deal found 9/15$240
This United Airlines deal was found by Cheapflights users on 9/15. 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.
mar. 9/308:28 pmDEN - YOW
1 stop15h 36mUnited Airlines
jue. 10/165:15 amYOW - DEN
1 stop8h 43mUnited Airlines
Deal found 9/15$286
This United Airlines deal was found by Cheapflights users on 9/15. 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.
dom. 10/1911:59 pmDEN - YOW
1 stop7h 59mUnited Airlines
vie. 10/245:25 pmYOW - DEN
1 stop6h 35mUnited Airlines
Deal found 9/15$290
This Kiwi.com deal was found by Cheapflights users on 9/14. 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.
mié. 10/88:00 amDEN - YUL
2 stops14h 27mMultiple Airlines
sáb. 10/115:30 pmYUL - DEN
1 stop19h 54mMultiple Airlines
Deal found 9/14$293

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 septiembre 16, 2025.
Use the filters below to find and compare flights from Denver to Ontario that are best for you.

Fly from

Denver

Fly to

Ontario

Route

Depart

Return

Price

DenverOttawa

DEN - YOW

DENYOW

Denver Intl

mié. 10/22

6:00 am-5:06 pm

1 stop9h 06m

Ottawa

sáb. 10/25

5:15 am-10:04 am

1 stop6h 49m

$286

DenverOttawa

DEN - YOW

DENYOW

Denver Intl

mar. 9/30

8:28 pm-2:04 pm

1 stop15h 36m

Ottawa

jue. 10/16

5:15 am-11:58 am

1 stop8h 43m

$286

DenverOttawa

DEN - YOW

DENYOW

Denver Intl

mié. 10/15

11:59 pm-9:11 am

1 stop7h 12m

Ottawa

mié. 10/22

5:15 am-10:04 am

1 stop6h 49m

$286

DenverOttawa

DEN - YOW

DENYOW

Denver Intl

dom. 10/19

11:59 pm-9:58 am

1 stop7h 59m

Ottawa

vie. 10/24

5:25 pm-10:00 pm

1 stop6h 35m

$290

DenverOttawa

DEN - YOW

DENYOW

Denver Intl

mié. 10/15

10:29 pm-12:22 am

2 stops23h 53m

Ottawa

mié. 10/22

4:25 pm-8:15 am

1 stop17h 50m

$297

DenverOttawa

DEN - YOW

DENYOW

Denver Intl

sáb. 10/18

12:36 am-4:57 pm

1 stop14h 21m

Ottawa

vie. 10/24

5:55 am-3:59 am

2 stops24h 04m

$300

DenverToronto

DEN - YTZ

DENYTZ

Denver Intl

vie. 10/24

11:15 am-7:49 pm

1 stop6h 34m

Toronto Island

vie. 10/31

12:30 pm-7:55 pm

1 stop9h 25m

$333

DenverMontreal

DEN - YUL

DENYUL

Denver Intl

vie. 10/3

12:15 pm-12:27 am

2 stops34h 12m

Montreal Pierre Elliott Trudeau Intl

sáb. 10/11

5:30 pm-11:24 am

1 stop19h 54m

$341

DenverToronto

DEN - YTZ

DENYTZ

Denver Intl

vie. 10/17

8:58 pm-12:17 pm

1 stop13h 19m

Toronto Island

dom. 10/26

9:15 am-8:08 pm

1 stop12h 53m

$373

DenverToronto

DEN - YTZ

DENYTZ

Denver Intl

mar. 10/14

8:22 pm-12:17 pm

1 stop13h 55m

Toronto Island

mar. 10/21

1:35 pm-8:30 pm

1 stop8h 55m

$378

Flights are sorted by cheapest round-trip flights first.

Deals found on 9/14

Showing 1-10 of 60 results
1
2
3
...
6

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

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

Currently, January is the cheapest month in which you can book a flight from Denver to Region of Ontario (average of $243). Flying from Denver to Region of Ontario in August is currently the most expensive (average of $348). 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 septiembre 16, 2025.

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 septiembre 16, 2025.

The most flights from DEN to CAON are scheduled on a Monday (11 on average). You will have fewer flight options on Tuesday, which is when the least amount of flights are scheduled (10 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 septiembre 16, 2025.
Read reviews from past customers who have flown Delta, United Airlines, and WestJet from Denver to Ontario. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Delta
8.0
Very good
7,957 reviews

Comfort

7.9

Food

7.3

Crew

8.5

Entertainment

7.9

Boarding

8.2

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
7,957 reviews
Delta
8.0
Very good
7,957 reviews

Comfort

7.9

Food

7.3

Crew

8.5

Entertainment

7.9

Boarding

8.2

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
8,924 reviews
Delta
8.0
Very good
7,957 reviews

Comfort

7.9

Food

7.3

Crew

8.5

Entertainment

7.9

Boarding

8.2

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
3,093 reviews
Delta
8.0
Very good
7,957 reviews

Comfort

7.9

Food

7.3

Crew

8.5

Entertainment

7.9

Boarding

8.2

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
10,000 reviews
Delta
8.0
Very good
7,957 reviews

Comfort

7.9

Food

7.3

Crew

8.5

Entertainment

7.9

Boarding

8.2

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 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 United Airlines, Air Canada, and WestJet fly from Denver to Region of Ontario in about 6h 34m. The time it takes to get you to your destination can typically vary by up to 27h 38m. The distance between Denver and Region of Ontario is about 1322 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?

    $105 is the cheapest one-way deal found within the past few days, from WestJet. You may also be able to find cheap deals on United Airlines and Delta, with prices starting from $130 and $172, 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 Austrian Airlines (74%), Brussels Airlines (74%) and Air Canada (73%).

  • 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 $1,014, our data indicates the cheapest price to be $182. The most popular route (Denver Intl - Montreal Pierre Elliott Trudeau Intl), is priced around $338.

  • 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, January is the cheapest month in which you can book a flight from Denver to Region of Ontario (average of $243). Flying from Denver to Region of Ontario in August is currently the most expensive (average of $348). 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

Browse thousands of different options on Cheapflights for your next trip

Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.

Alternative routes for Denver to Ontario

See prices for flight routes from nearby airports that may be better suited for you.
Denver to Vancouver Intl flights
Denver to Calgary flights
Denver to Pierre Elliott Trudeau Intl flights
Denver to Pearson Intl flights
Denver to Abbotsford flights
Denver to Edmonton flights
Denver to Toronto Island flights
Denver to Halifax flights
Denver to Winnipeg flights
Colorado Springs to Vancouver Intl flights
Denver to Regina flights
Denver to Québec City flights
Denver to Victoria flights
Denver to Kelowna flights
Denver to Charlottetown flights
Colorado Springs to Pearson Intl flights
Denver to Hamilton flights
Aspen to Vancouver Intl flights
Denver to Region of Waterloo Intl flights
Colorado Springs to Pierre Elliott Trudeau Intl flights
Durango to Calgary flights
Denver to Ottawa flights
Denver to Yellowknife flights
Colorado Springs to Calgary flights
Denver to London flights
Vail to Vancouver Intl flights
Grand Junction to Edmonton flights
Montrose to Vancouver Intl flights
Denver to Whitehorse flights
Grand Junction to Vancouver Intl flights
Montrose to Calgary flights
Colorado Springs to Winnipeg flights
Denver to Saskatoon flights
Denver to Terrace flights
Denver to Smithers flights
Hayden to Calgary flights
Colorado Springs to Edmonton flights
Denver to St. John's flights
Colorado Springs to St. John's flights
Colorado Springs to Victoria flights
Colorado Springs to Ottawa flights
Vail to Pearson Intl flights
Colorado Springs to Québec City flights
Aspen to Halifax flights
Aspen to Ottawa flights
Grand Junction to Calgary flights
Grand Junction to Thunder Bay flights
Durango to Pearson Intl flights

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 septiembre 16, 2025.
AirlineCheapestAverageFlexibilityOn-time
WestJetCheapest$143Average$303FlexibilityNo cancel feeOn-time60%
Air CanadaCheapest$224Average$667FlexibilityNo cancel feeOn-time67%
United AirlinesCheapest$244Average$504FlexibilityNo cancel feeOn-time69%

100% Free

Cheapflights is completely free to use, so you can start saving the moment you arrive.

Book with Flexibility

Our users can plan ahead with confidence and find flights with no change fees

Travel Smart

Millions of people come to us for their flight needs every year. We help make travel planning easy by providing useful insights and data-driven graphs that can inform your decisions.