$123 Find Cheap Flights from Denver to Ontario - Compare and Save

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Cheap Flights from Denver to Ontario

Cheapest round-trip prices found by our users on KAYAK in the last 5 days
Toronto
Toronto1 stop$296
Ottawa
Ottawa2 stops$361
London
London1 stop$457
Toronto
Toronto1 stop$296
Ottawa
Ottawa2 stops$361
London
London1 stop$457
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?

Flight prices are below average for this route right now.

Flights to Region of Ontario from Denver usually cost between $468 and $660 in September.
The lowest price found in the past 5 days was $301 on Multiple Airlines (Sep 14-Sep 21).

What is the cheapest Denver to Ontario flight route?

The cheapest ticket to Ontario from Denver found in the last 5 days was to Toronto, at $240 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 5 days was $240.

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

The cheapest time of day to fly to Ontario is generally in the afternoon, when round-trip flights cost $715 on average. Morning departures are around 5% 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 $819.

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

No, with an average price for the route of $653, prices are generally cheapest when you fly direct.

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

The cheapest month for flights from Denver to Ontario is October, when tickets cost $510 (return) on average. On the other hand, the most expensive months are February and May, when the average cost of round-trip tickets is $686 and $655 respectively.

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

If you are looking for a flight deal from Denver to Ontario, look for departures on Fridays and avoid leaving on a Saturday, as it's usually the priciest day. When flying back from Ontario, Thursday 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 get a below average price on the flight from Denver to Ontario, you should book around 4 weeks before departure, which saves you about 49% compared to booking last minute. For the absolute cheapest price, our data suggests you should book 6 weeks before departure.

Good to know

Low season

November

Cheapest flight

$123
Best time to beat the crowds with an average 21% drop in price.
Most popular time to fly with an average 2% increase in price.
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.

Reviews of the top airlines flying from Denver to Ontario

 
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.
7.4
United AirlinesOverall score based on 10102 reviews
6.7Food
8.1Crew
7.1Entertainment
7.3Comfort
7.7Boarding
Airline reviews

The entertainment they offer could use some games, and maybe they could add some cookies to the snack menu. And the automated messages are a bit repetitive. But it was comfortable temperature wise and the seats were comfortable. The crew is very polite and helpful

6.0 GoodAnonymous, Jun 2026
Read more United Airlines reviews

The entertainment they offer could use some games, and maybe they could add some cookies to the snack menu. And the automated messages are a bit repetitive. But it was comfortable temperature wise and the seats were comfortable. The crew is very polite and helpful

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.

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

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

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.

Flight was good but there are way to many announcements for credit cards etc.

Overall good flight. The pilots were excellent. It was a nice flight, but the seats were a little uncomfortable.

The free snack options are pretty pitiful for a 2.40h flight.

Not worth the premium paid for the first class ticket

Fine. Though no food or entertainment so the survey needs to be updated with those options.

We had a very long delay. First the inbound flight took a while, then maintenance, they “fixed it” to then do boarding and leave the gate, and waste a lot of time to have to go back to the gate and eventually deplane. Had to wait for a new aircraft, wait for a gate, and do the whole thing again. Instead of leaving at 9:50am we left until past 1. I could’ve not woken up at 5am, or spend some more time with my family if they gave more grace period of time between flights to give some time in case of any issues. But they have to make all and every dollar possible

Most expensive flight… and they are trying to pinch more and more money out of you. Baggage, snacks, pillows, headphones… — so many airlines do far better than this… surely a national airline can do better?

Air Canada should allow basic economy passengers to upgrade if they wish to do so.

My second flight ended up being through United and it was fine. Again, just frustrating that it was so late.

I had written all my complaints on my trip from Grand Junction to Denver so I will repeat it here! I was absolutely appalled that I had to pay for a regular seat that I choose 24 hrs before boarding! Also I checked my large bag which I had to pay for as well, and by the time I boarded all the room in the bins were gone so also had to check that one. I noticed people pulling out oversized suitcases, bigger than the measurements stated for carry on, and also large pack packs stuffed full! So these people were taking up 2 or 3 spaces that the rest of us should have been able to use but couldn’t! NoTV on the flight! Thankfully I had downloaded the United Airlines app and was able to watch movies on my phone. Don’t remember the last time I flew in a plane with no movie screens!

My flying experience with Air Canada was good but the wheelchair situation wasn't good at all and if would be good to make sure that they have the appropriate services available for your traveling passengers.

Air Canada flights offer excellent service. This flight from DEN to YYZ in an Airbus A220-300 was so sooth it was almost like spending a couple of hours reading a good book, except for the cabin crew who provide friendly, thoughtful service throughout the flight. Kudos to AC pilots, cabin crew and management. I’ve now added Airbus 220.300 to my preferred list if planes to fly in.

Lots of delay! Cheotic and disorganized! Aircraft had technical problem and was stopped and returbed to the gate while taking off! . United States is sinking under Joe Biden!

Ops was very poor. 2 of 2 legs were both late. Air Canada changed our seats 3x and my friend and I never did get to sit together. Flight attendant opened the lavatory on me and was not professional about it. Food was blah. The worst part is that the flight was so late from Toronto that we missed our connection in Athens. We lost out on other airline tickets and nobody even said sorry or tried to help. Our return flight was cancelled and my friend and I are rebooked on completely different flights next week.

Legroom was not good and can be improved and food needs upgrade.

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

Information on your arrival and departure airports