$110 Find Cheap Flights from Denver to Ontario

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from Denver to Ontario departing on 6/2. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
1 adult
1 adult, Economy, 0 bags

KAYAK searches hundreds of travel sites at once for deals on flights to Ontario

 
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Denver to Ontario, as well as popular online travel agencies
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Denver to Ontario, as well as popular online travel agencies
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Cheap Flights from Denver to Ontario

Cheapest round-trip prices found by our users on KAYAK in the last 72 hours
Toronto
Toronto2 stops$272
Ottawa
Ottawa2 stops$425
London
London1 stop$492
Toronto
Toronto2 stops$272
Ottawa
Ottawa2 stops$425
London
London1 stop$492

Book Cheap Denver to Ontario Plane Tickets

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from Denver to Ontario that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.
Discover the best prices for you by selecting your travel dates on KAYAK.

Recent round-trip flight deals from Denver to Ontario

Tue, Jun 16 - Mon, Jun 22
Multiple Airlines Logo
10:25 am - 5:45 am
DEN
-
YYZ
17h 20m
2 stops
Multiple Airlines Logo
4:45 pm - 2:20 pm
YYZ
-
DEN
23h 35m
1 stop
$272Multiple Airlines
Sun, Jun 14 - Mon, Jun 22
Multiple Airlines Logo
6:10 am - 1:05 am
DEN
-
YYZ
16h 55m
2 stops
Multiple Airlines Logo
4:45 pm - 2:20 pm
YYZ
-
DEN
23h 35m
1 stop
$273Multiple Airlines
Tue, May 12 - Tue, May 19
Multiple Airlines Logo
12:34 pm - 5:45 am
DEN
-
YYZ
15h 11m
2 stops
Multiple Airlines Logo
9:45 am - 3:25 am
YYZ
-
DEN
19h 40m
1 stop
$274Multiple Airlines
Sun, Jun 14 - Mon, Jun 22
Multiple Airlines Logo
10:29 pm - 8:00 pm
DEN
-
YYZ
19h 31m
1 stop
Multiple Airlines Logo
4:45 pm - 2:20 pm
YYZ
-
DEN
23h 35m
1 stop
$276Multiple Airlines
Sun, Jun 14 - Tue, Jun 23
Multiple Airlines Logo
10:29 pm - 8:00 pm
DEN
-
YYZ
19h 31m
1 stop
Multiple Airlines Logo
10:50 am - 12:38 am
YYZ
-
DEN
15h 48m
2 stops
$277Multiple Airlines
Tue, Jun 16 - Mon, Jun 22
Multiple Airlines Logo
10:29 pm - 5:09 pm
DEN
-
YYZ
16h 40m
1 stop
Multiple Airlines Logo
4:45 pm - 2:20 pm
YYZ
-
DEN
23h 35m
1 stop
$283Multiple Airlines
Wed, May 13 - Wed, May 20
Multiple Airlines Logo
2:40 pm - 9:55 pm
DEN
-
YYZ
29h 15m
1 stop
Multiple Airlines Logo
4:45 pm - 12:50 pm
YYZ
-
DEN
22h 05m
1 stop
$290Multiple Airlines
Thu, Jun 4 - Sun, Jun 7
Multiple Airlines Logo
6:10 am - 8:00 pm
DEN
-
YYZ
11h 50m
1 stop
Multiple Airlines Logo
10:30 pm - 3:58 am
YYZ
-
DEN
31h 28m
2 stops
$297Multiple Airlines
Wed, Jun 17 - Fri, Jun 19
WestJet Logo
12:15 pm - 11:45 pm
DEN
-
YUL
9h 30m
1 stop
WestJet Logo
8:00 pm - 11:20 am
YUL
-
DEN
17h 20m
1 stop
$435WestJet
Fri, Sep 25 - Sun, Sep 27
WestJet Logo
12:15 pm - 11:45 pm
DEN
-
YUL
9h 30m
1 stop
WestJet Logo
5:30 pm - 11:20 am
YUL
-
DEN
19h 50m
1 stop
$441WestJet
Booking Insights

KAYAK's insights & trends for Denver to Ontario flights

Get data-powered insights and trends into flights from Denver to Ontario to help you find the cheapest flights, the best time to fly and much more.

How much is a round-trip flight from Denver to Region of Ontario?

This analysis is based on the cheapest round-trip price found on KAYAK in the last 12 months by searching for a flight from Denver to Region of Ontario departing in June.

What is the cheapest Denver to Ontario flight route?

Data is based on round-trip flight searches on KAYAK over the past month.

The cheapest ticket to Ontario from Denver found in the last 72 hours was to Toronto, at $386 round-trip. The most popular route is from Denver (DEN) to Toronto Pearson Intl Airport (YYZ), and the cheapest round-trip airline ticket found on this route in the last 72 hours was $386.

What is the cheapest time of day to fly to Ontario?

The average price for all round-trip flights from Denver to Ontario depending on the time of departure, clicked by users on KAYAK in the last 2 weeks.

The cheapest time of day to fly to Ontario is generally in the afternoon, when round-trip flights cost $687 on average. Morning departures are around 3% cheaper than evening flights, on average. The most expensive time of day to fly to Ontario is generally in the evening, which is peak travel time and where the average cost of a ticket is $716.

Can I save money by flying with a layover from Denver to Ontario?

The average round-trip price for all non-stop flights, flights with one layover, and flights with two layovers for the route found by users searching on KAYAK in the last 2 weeks.

No, with an average price for the route of $622, prices are generally cheapest when you fly direct.

What is the cheapest month to fly from Denver to Ontario?

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from Denver to Ontario, removes the top 0.1% to account for outliers, and then takes the median of all values for each month.

The cheapest month for flights from Denver to Ontario is September, when tickets cost $468 (return) on average. On the other hand, the most expensive months are February and January, when the average cost of round-trip tickets is $631 and $620 respectively.

What’s the cheapest day of the week to fly from Denver to Ontario?

The average price of all round-trip flights from Denver to Ontario clicked on KAYAK for each day over the last 12 months.

If you are looking for a flight deal from Denver to Ontario, look for departures on Thursdays and avoid leaving on a Sunday, as it's usually the priciest day. When flying back from Ontario, Friday is the cheapest day to fly and Monday is the most expensive.

How far in advance should I book a flight from Denver to Ontario?

To calculate weekly average prices, KAYAK takes all prices for each week before departure over the last year for round-trip flights from Denver to Ontario, removes the top 0.1% to account for outliers, and then takes the average of all the values for each week.

To get a below average price on the flight from Denver to Ontario, you should book around 3 weeks before departure, which saves you about 41% compared to booking last minute. For the absolute cheapest price, our data suggests you should book 7 weeks before departure.

Good to know

Low seasonNovember
Cheapest flight$110
Best time to beat the crowds with an average 9% drop in price.
Most popular time to fly and prices are also 12% lower on average.
Flight from Denver to Toronto Pearson Airport

FAQs - booking Ontario flights

  • How does KAYAK find such low prices on flights from Denver to Ontario?

    KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Denver to Ontario.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Denver to Ontario?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight from Denver to Ontario is likely to change within 7 days, so travelers know whether to wait or book now.

  • What is the Hacker Fare option on flights from Denver to Ontario?

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly from Denver to Ontario with an airline and back with another airline.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Denver to Ontario?

    Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying from Denver to Ontario up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

Reviews of the top 4 airlines serving from Denver to Ontario

 
See real verified KAYAK customer reviews for airlines flying from Denver to Ontario. Airline scores are aggregated from all reviews left by passengers on KAYAK after flying with an airline. KAYAK doesn’t show reviews that are older than 5 years. Learn how KAYAK collects reviews.
Need help choosing which airline to fly with from Denver to Ontario? KAYAK airline reviews give an overall score for each airline based on loads of factors, including comfort, boarding, in-flight entertainment and more, to make your decision easier. See airline scores according to verified KAYAK customer reviews.
7.9
DeltaOverall score based on 8422 reviews
8.5Crew
7.9Comfort
7.2Food
8.1Boarding
7.8Entertainment
Airline reviews

Everything went smoothly, although the usual gripes about airline travel were still present: the boarding process is inefficient, the snack selection is limited, and so on. Since there was extra space on the flight, the gate agent rearranged many people's seats to put people on the aisles and windows, leaving the middle seats empty, as much as possible, which was pretty great.

10.0 ExcellentDavid, Apr 2026
DTW - SFO
Read more Delta reviews

Everything went smoothly, although the usual gripes about airline travel were still present: the boarding process is inefficient, the snack selection is limited, and so on. Since there was extra space on the flight, the gate agent rearranged many people's seats to put people on the aisles and windows, leaving the middle seats empty, as much as possible, which was pretty great.

Landed without a gate ready. Plane is extremely old and dirty.

All the amenities was wonderful, if they could keep their prices that low. I'd fly with them all the time.

Very old plane with no inflight entertainment. I purchased the internet pass and it was nearly unusable.

My tray was broken so i had no place to work or eat except my lap. Flight attendant said I would get an email with some credit or miles, it was a complete waste of time as I could only function at about 20% of normal. I have not received anything yet.

Short trip, no food and therefore no expectation for much interaction with staff who were pleasant and professional. My critique is on comfort of the seats. Exit rows and comfort seats do not provide enough personal space for 3 side-by-side seats, especially when in the middle row. Some passengers are not considerate of the middle seat and there should be signs that state something to the effect of: "please consider giving middle seats use of the armrests."

My flight yesterday evening was delayed 3.5 hours with no water or food service. Poor experience

Transparency from pilots, quick boarding and exiting the plane, staff greeted to each and everyone,

Didn't like sitting on the waiting pad for 30 minutes right after departing the gate. If you're going to do that, just don't board so people can still get up and walk around in the terminal. My luggage was damaged by the baggage handlers.

Pilots lied about waiting on “paperwork”. Sat in the plane for over an hour, waiting on some papers to be printed according to the pilot and then all of a sudden he says good news maintenance is finally on their way. Maybe they can fix it before we get our paperwork. Ended up missing my connection in LaGuardia and as a result, had a fly home to Lexington instead of the Louisville airport. Then paid $100 to uber to Louisville since it was midnight by the time I got in. I wish they would just be transparent with passengers sometimes and not try to beat around the bush on why things are delayed.

Putting people that close to the bathroom, where you have to look into the bathroom as people are exiting and entering was not great and the smell was also not great. I know the airlines are desperate for more chairs, but that seat is a crime.

Every staff member was professional, friendly and courteous. The pizza twist was ok. It was warm but too much dough.

one staffer was frustrated (it happen); the flight was late and the pilot mentioned they'll make amend but the snacks were the same, other than that the aircraft was clean and everything went smooth, no complaints

Wonderful in-seat entertainment with seatback screens and huge selection of quality movies. The ability to bluetooth connect headphones was amazing.

No seat back entertainment. And app had a hard time getting entertainment loaded.

ticket agent lady wás very helpful , she arranged wheel chair for my elderly mother

Flight left on time and we arrived 25 minutes early! There was a gate available when we arrived so early on a busy Sunday afternoon! Flight attendants came around twice with the drinks cart.

Sitting on the runway after we land for almost two hours! Not sure if we should blame United or Just Dumpy Vance.

Flight was late - I was downgraded from first class to coach

United overall experience is great these days. Airport experience was very organized. Staff on flight were great. App and information as good as it gets.

I didn’t have any food but my Prosecco hit the spot. We left on time and the crew was friendly.

I thought the coffee was excellent! The wait for the luggage was acceptable.. It left and arrived on time. My son found that his device worked very well and he really enjoyed his flight! The stewardess moved him up to the emergency exit and he very much appreciated that!

I wasn’t able to book or pay for a seat and they forgot to check me in for my third flight so I spent 24 hours in Toronto waiting for another one.

Everything was good except for flight delay, but it was because of the snow storm in the arrival airport.

The flight was cancelled less than 24 hours before departure. The alternate flight was a day later going from Grenada to Toronto to Vancouver to Calgary to Montreal. 2 days in the air. Not serious, Very bad service

I like the wider seats, Plus lots of legroom, Lacking entertainment, no tv or screen to play with

Liked in-flight wifi Did not like - nothing to complain, really. All good

The keg from Edmonton to Toronto My wife found it very cold. Other than that great flight.

Smooth flight Staff were courteous and welcoming upon entering and exiting the plane Pilot and crew provided frequent updates Leg space was not pleasant but manageable

Everything was good except I was a bit disappointed that I had to pay US $150 for bags.

It was a problem because there was a delay where we sat before taking off from newark,then when landed in Toronto we sat on tarmac and they wouldn't let us out for a long period of time. When we finally were released to the airport in Toronto the attendant scanned our boarding pass that we were here for our connection to Brazil. We ran all the way to the gate and they said at the gate the door is shut so we can not let you on the plane. We explained that we were checked in by the attendant when we arrived at Toronto airport to go to Brazil and they should not have shut the door. We were ignored at the gate

Flight home was delayed multiple times, did not get home until 2am

the check-in lady at ORD was extremely rude and unprofessional. very disappointed as it was supposed to be a celebration for my wife's birthday and it really put a damper on things. if i wanted to be treated like trash, i would have flown Economy! (as opposed to business class)

My original flight was cancelled and then rebooked four hours later on a recovery flight, but I was checked in as stanby and had no seats so as a family of four we were concerned about not being seated altogether. Our flight then got delayed by another 1.5 hours and when seats were assigned at the gate, three of the four of us were together and we could get my wife closer, they offered no assistance.

Good boarding but extremely cold temperature in both flights (60 F!).

Very rude gate attendants in San Francisco who didn’t let me bring my little carry on (smaller than usual size) and after boarding I realized that there still were a lot of overhead compartment space (like a full section available in some spots). That made me lose 30 minutes at my destination at 1am and it could have broken something fragile that I had in it

I want to thank Carlos at the Miami AC desk - he was amazing and went over and above to help us out. Thank you Carlos and all the best to you!!! You made our faith in AC feel great! Sincerely, David Cubitt

Flight was canceled due to mechanical issues. After a considerable wait in the queue, Air Canada customer service was very helpful to get us on another flight. I am disappointed to report our rescheduled flight is for three days from now. Three days of extra expenses and inconvenience is unacceptable.

Extremely disappointing. My original Denver–Vancouver–Bangkok itinerary was cancelled due to a crewing issue. I was not proactively supported and had to drive back home after already reaching the airport. Communication was poor throughout, and attempts to contact customer service resulted in being on hold for nearly three hours without reaching anyone. Instead of being rebooked on the same direct routing the following day, I was rerouted onto a much longer itinerary via multiple cities and airlines, which resulted in arriving approximately 30 hours later than scheduled. At Denver airport, there was no visible Air Canada representative available to properly assist. Ground staff offered no real support beyond directing passengers to a phone number. There was no clear communication, no ownership, and no meaningful customer care during a major disruption. The final journey involved three flights instead of the original two, significantly increasing travel time and stress. Overall, the handling of the cancellation and lack of customer support was unacceptable. What could have been better? Clear communication during the cancellation Accessible customer service (phone support that actually answers) Proper in-person assistance at the airport Rebooking onto a comparable routing rather than a significantly longer one

The last 3 hours it was freezing cold in row 56. Multiple people had their winter coats on and were utilizing the blankets provided by the airline. I also did not have easy access to figure out how to book my food allergy and advance for my meals. Most of everything I received was something I couldn't eat. This needs to be made more accessible. Also, I'm 5'10 which is the average height of the American male. I flew from Philadelphia to Toronto and then to Tokyo and the seats were absolutely unbearable. For that long of a flight it is impossible to get comfortable when doing anything. Flights need to have more space and stop prioritizing costs over people.

Everything you need to know for your flight from Denver to Ontario

Information on your arrival and departure airports