$100 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 10/22. 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

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
Toronto1 stop$217
Ottawa
Ottawa1 stop$286
London
London1 stop$417
Toronto
Toronto1 stop$217
Ottawa
Ottawa1 stop$286
London
London1 stop$417

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

Wed, Oct 22 - Sun, Oct 26
Multiple Airlines Logo
8:21 pm - 9:07 pmDEN-YYZ
22h 46m1 stop
Multiple Airlines Logo
4:00 pm - 8:12 amYYZ-DEN
18h 12m1 stop
$217Multiple Airlines
Find Deal
Wed, Oct 15 - Wed, Oct 22
Multiple Airlines Logo
8:21 pm - 9:07 pmDEN-YYZ
22h 46m1 stop
Multiple Airlines Logo
9:45 am - 11:10 pmYYZ-DEN
15h 25m1 stop
$221Multiple Airlines
Find Deal
Fri, Oct 3 - Sun, Oct 5
WestJet Logo
12:15 pm - 12:22 amDEN-YYZ
10h 07m1 stop
WestJet Logo
10:25 pm - 11:24 amYYZ-DEN
14h 59m1 stop
$254WestJet
Find Deal
Tue, Sep 30 - Thu, Oct 16
United Airlines Logo
8:28 pm - 2:04 pmDEN-YOW
15h 36m1 stop
United Airlines Logo
5:15 am - 11:58 amYOW-DEN
8h 43m1 stop
$286United Airlines
Find Deal
Sun, Oct 19 - Fri, Oct 24
United Airlines Logo
11:59 pm - 9:58 amDEN-YOW
7h 59m1 stop
United Airlines Logo
5:25 pm - 10:00 pmYOW-DEN
6h 35m1 stop
$290United Airlines
Find Deal
Mon, Oct 6 - Sat, Oct 11
WestJet Logo
12:15 pm - 12:27 amDEN-YUL
34h 12m2 stops
WestJet Logo
5:30 pm - 11:24 amYUL-DEN
19h 54m1 stop
$302WestJet
Find Deal
Fri, Oct 24 - Fri, Oct 31
Air Canada Logo
11:15 am - 7:49 pmDEN-YTZ
6h 34m1 stop
Air Canada Logo
12:30 pm - 7:55 pmYTZ-DEN
9h 25m1 stop
$333Air Canada
Find Deal
Tue, Oct 28 - Fri, Oct 31
Air Canada Logo
8:45 am - 9:00 pmDEN-YUL
10h 15m1 stop
Air Canada Logo
7:30 am - 5:44 pmYUL-DEN
12h 14m1 stop
$354Air Canada
Find Deal
Wed, Oct 1 - Tue, Oct 7
Delta Logo
5:45 am - 4:05 pmDEN-YUL
8h 20m1 stop
Delta Logo
12:36 pm - 8:15 pmYUL-DEN
9h 39m1 stop
$402Delta
Find Deal
Wed, Oct 22 - Sat, Oct 25
Delta Logo
5:45 am - 12:22 amDEN-YOW
16h 37m2 stops
Delta Logo
5:55 am - 1:39 pmYOW-DEN
9h 44m2 stops
$427Delta
Find Deal
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.

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 $303 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 $303.

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 $510, 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 March, when tickets cost $253 (return) on average. On the other hand, the most expensive months are February and November, when the average cost of round-trip tickets is $553 and $549 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 Sunday 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 4 weeks before departure, which saves you about 59% compared to booking last minute. For the absolute cheapest price, our data suggests you should book 25 weeks before departure.

Good to know

Low seasonApril
Cheapest flight$100
Best time to beat the crowds but there is an average 12% increase in price.
Most popular time to fly and prices are also 2% lower on average.
Flight from Denver to Montreal

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.

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

    The cheapest time of day to fly to Ontario is generally at night, when round-trip flights cost $588 on average. Morning departures are around 8% more expensive than evening flights, on average. The most expensive time of day to fly to Ontario is generally in the morning, which is peak travel time and where the average cost of a ticket is $721.

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 7957 reviews
8.2Boarding
7.9Comfort
8.5Crew
7.9Entertainment
7.3Food
Airline reviews

The staff and the boarding procedure were all amazing . The one flight was not equipped with WIFI which now adays seems odd. All in all the experience was good

8.0 ExcellentAnonymous, Sep 2025GFK - MSP
Read more Delta reviews

The staff and the boarding procedure were all amazing . The one flight was not equipped with WIFI which now adays seems odd. All in all the experience was good

Passengers need to check in big baggage instead of bringing on the plane. That cause inconvenience for everyone. Otherwise flight was good.

Perfect flight both ways. On time, courteous staff, plane comfortable and cool. Best domestic flights I’ve had in awhile.

The food was terrible especially for a 15 hour international flight. The crew was unpleasant as well.

Really low quality food especially for an international flight. The crew also was surprisingly unpleasant except couple of ladies. I know we were not in first class but that’s no reason to treat customers as less.

Flight delayed for two and half hours and then canceled altogether due to mechanical issues. No mechanic onsite to fix so had to send one from LAX.

Quick check in. Everything went smooth. I don't know what can be done about airline food.

Crew was good. The reservation got mixed up and they didn't have my TSA number. I am also a Silver Medallion and wasn't able to use Sky Priority.

Delta made it easy, comfortable and timely. The crew was fantastic.

This route with Delta always has delays or is cancelled. Aircrafts seem smaller and older. I fly Delta quite a bit - haven’t had issues with the international flights. But this route has always been the troublesome one

Terrible. They wouldn't allow me on my flight on the 14th..

Impressed with the service despite turbulence because of the weather. Both flights arrived before their scheduled times.

Great experience…left a bit behind schedule but made up fir that in the air and landed 10 minutes early 😁

The seat and leg room was not good. The food and beverage service was good.

For economy, it was very good. Staff was great, they even let some of us change seats for more leg room... Put an empty seat between us which was fantastic for a 12hr flight. Onboard entertainment was excellent, I think over 200 choices of movies/tv/etc The bad was the barely/nonfunctional wifi that cost either $16.99 or 1700 miles (full flight). It was atrocious... Definitely the worst of the last 3 long haul major airlines I was on the last few months.

Electric plugs didn't work. Entertainment system wasn't working

The design of the light switch on the arm rest is ridiculous.

The gate attendant let me walk right by her with a bag too big for the overhead compartment

Overall, it was a good experience. Boarding was good and there was plenty of overhead bin space for everyone’s carryons (even when we boarded toward the end). Only improvement would be to offer trash service more regularly.

David went above and beyond to make our flight the best that it could be

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.

Flight itself good .Landing at terminal3 and connections to terminal1,it is connections nightmare,specially for disable person

The seats very Uncomfortable, no meal and no entertainment for a 4Hours flight. Smooth Flight, Great Take off and landing. Superb crew!

The flight attendants were super! They created a cosy and warm flight atmosphere!

West Jet flight was cancelled and I was not notified. I found out when I tried to check in on-line. Spent 4 hours on the phone with West Jet and Just Fly trying to figure what happened.

Only issue was checking in took over an hour and was very stressful. It all worked out, but we weren't sure for a while.

It was good, flight was on time, boarding was smooth and done in zones, food was good too but there was no form of entertainment. Luggage’s were intact. So an overall good flight

Flight was delayed 3 times. Then cancelled due to pilot being timed out. They refused hotel vouchers. Gate attendants were very rude and could not help you at all.

Short flight. Everything was fine except the flight was delayed twice for a total of an hour.

I found the boarding easy and my seat was very comfortable as I had a lot of leg room. I am not too happy that I no longer have lounge access even though I used to get it with my TD credit card.

Flight cancelled. Major disruption to our travel. Do not use Air Canada from KC. To few flights.

There labor disputes cancelled my flight less than 24 hours before my boarding time but there customer service/website was easy enough to navigate and they rebooked me for no upcharge.

Re luggage I carried a backpack only. I did not check any bags in. However there were other passengers with carry on luggage going in the plane. My question is why are others allowed to have a carry on luggage inside the plane? Shouldn’t they have dropped it off at the gate? I’m asking because I could have brought the same thing instead of a backpack only. Please clarify for future reference. Thank you.

Like the service. Very hard to communicate or contact when have problems

Check in staff was incredibly rude and condescending. When I arrived at the gate I had been charged $125 for a checked back. I did have or check a bag. When I brought this to the attention of the staff member who checked me in, she said that she made a mistake and there was nothing she could do about it. I asked her to remove the charge and refund credit card, she said she could not and that I had to call my credit card company to contest the charge. I called Air Canada customer support, was put on hold, after 43 minutes a received a messages stating customer service was overwhelmed with calls and was then hung up on.

Refreshments and Air Hostess was good. Issues with customs in Toronto caused flight to depart and left me behind twice. Vouchers for delayed flight needs to increase.

Long wait to check in at the priority counter in Toronto

I had no communication, receipt etc from Air Canada until hours before flight

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

Information on your arrival and departure airports

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