$147 Find Cheap Flights from Colorado to Ontario

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1 adult, Economy, 0 bags

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Low seasonJanuary
Cheapest flight$147
Most popular time to fly and prices are also 3% lower on average.
Flight from Denver to Montreal

FAQs for booking flights from Colorado to Ontario

  • How does KAYAK find such low prices on flights from Colorado 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 Colorado to Ontario.

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

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight from Colorado 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 Colorado 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 Colorado 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 Colorado 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 Colorado to Ontario up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

  • Which airlines fly most frequently to Ontario?

    Colorado and Ontario are connected by different airlines. The airlines that fly that route the most regularly are United Airlines (49 flights per week), Air Canada (45 flights per week), and Austrian Airlines (20 flights per week).

  • How many airports are there in Ontario?

    There are 24 airports in Ontario. The busiest airport is Toronto Pearson Airport (YYZ), with 77% of all flights arriving there.

  • Which is the cheapest airport to fly into in Ontario?

    Prices will differ depending on the departure airport, but generally, the cheapest airport to fly to in Ontario is Toronto Pearson Intl Airport (YYZ), with an average flight price of $457.

  • What is the cheapest day to fly to Ontario?

    Based on KAYAK data, the cheapest day to fly to Ontario is Thursday where round-trip tickets can be as cheap as $617. On the other hand, the most expensive day to fly is Sunday, where round-trip prices are $805 on average.

  • 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 $683 on average. Morning departures are around 4% 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 $712.

  • What is the cheapest flight to Ontario?

    The cheapest ticket to Ontario from Colorado found in the last 72 hours was to Toronto Pearson Intl Airport, at $515 round-trip. The most popular route is 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 $515.

  • What is the cheapest month to fly from Colorado to Ontario?

    The cheapest month for flights from Colorado to Ontario is July, when tickets cost $500 (return) on average. On the other hand, the most expensive months are February and April, when the average cost of round-trip tickets is $686 and $578 respectively.

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

    To get a below average price on the flight from Colorado to Ontario, you should book around 4 weeks before departure, which saves you about 51% compared to booking last minute. For the absolute cheapest price, our data suggests you should book 7 weeks before departure.

  • How many cities have direct flights to Ontario?

    From Colorado, there are direct flights to Ontario from 1 city. This city is Denver and there are 118 direct flights each week.

  • How many direct flights to Ontario are there each day?

    There are around 17 direct flights from within Colorado to Ontario every day. Most flights (64%) depart in the afternoon.

  • How many direct flights to Ontario are there each week?

    Each week there are around 118 direct flights from within Colorado to Ontario. The most common day for departures is Thursday, with 15% of flights taking off on this day.

  • How long is the flight to Ontario?

    An average nonstop flight from Colorado to Ontario takes 9h 00m, covering a distance of 1422 miles. The shortest route is Denver (DEN) to Toronto Pearson Intl Airport (YYZ) with an average flight time of 3h 10m.

  • How many long-haul flights are there to Ontario each week?

    There are not any long-haul (6-12 hour flight duration) or medium-haul (3-6 hour flight duration) flights to Ontario. Instead, there are 118 short-haul flights (up to 3 hour flight duration), with the most arriving from Denver.

  • What are the most popular destinations in Ontario?

    Based on KAYAK flight searches, the most popular destination is Toronto (93% of total searches to Ontario). The next most popular destinations are Ottawa (5%) and London (1%). Searches for flights to Thunder Bay (0%) and to Kingston (0%) are also popular.

Reviews of the top 4 airlines serving from Colorado to Ontario

 
Need help choosing which airline to fly with from Colorado 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 8321 reviews
7.9Comfort
8.5Crew
7.2Food
8.1Boarding
7.8Entertainment
Airline reviews

The cabin temperature was nice and cool. The wifi was not working.

8.0 ExcellentMatt, Mar 2026
SEA - SJC
Read more Delta reviews

The cabin temperature was nice and cool. The wifi was not working.

Flight late, the waited for a long time for “personal” to arrive at gate to dock the plane in Rochester. So annoying. This flight was expected, why aren’t personel available for the jet bridge?

As previously noted, this flight was great: departure was timely, the crew was friendly and attentive, and wifi connectivity was seamless. In particular, I appreciated that the flight attendant just told me to stow the laptop right before takeoff/landing, and trusted me to do so (which I did!).

Kayak botched up the booking, i had to call delta and fix. In the process Delta failed to honor my comfort plus seat assignment that i had previously.

Entertainment is ok! Boarding and seat with zone is terrible. I paid for the seats but you didn’t give me what I paid for which is exit isles.

the crew cancel the morning service due to the weather. Then the flight got deverted to Nashville . we were on the ground for over two hours the only gave us water once... no food or any snacks.... the crew should have handled better and offered something to passengers.

My recent experience was excellent on Delta! I flew with Delta Comfort and I was really comfortable in my seat. I enjoyed the in-flight service. The flight attendants were so friendly and hospitable. I love the snack on the flight as well. This was my first time flying on Delta and I will definitely consider flying with them again.

My flight was cencaled due with the bad weather on Sunday the crew was poorly mistaken my luggage supposed depart with my flight instead I didn’t have my luggage for almost 3 days the website is poorly respond to my complain until I have someone to do it my connection smooth their not even respon or email me even the have my luggage

Delta needs to step its game up get a more reliable internet service. Internet service was non-existent for this flight.

Mechanical Delay of over an hour with multiple gate changes. Entertainment system down for rejuvenation.

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.

Entertainment kept turning itself off. Gave up on watching a movie.

Both of my flights arrived early and check in process was smooth

Wifi took a while to kick in and we had a maintenance issue that took over 40 mins at the gate in Washington before pulling back

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

Not United Airlines' fault. It's ORL airport's fault.

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 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.

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!

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.

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.

Was delayed at every point/ connection. Luggages missing for 5days. Had no medications for diabetes and high B/p. when bags where finally delivered on the 30th, the insulin and ozempic were no longer patent, as the ice pack had since dissolved and the authenticity of the med is now questionable, since they must be refrigerated. Please have them refund my bag fees. I should sue them for all the inconveniences caused to me.

The plane was delayed substantially due to a mechanical problem, that being said, the airline was very fair with providing a meal coupon for us. I would rather arrive late on a mechanically sound plane than the alternative. The food served in the plane was just awful, however and I recommend a new catering company.

I waiting for 2 hrs to retrieve my luggage. Didn't get home till 3am.

The flight left late and I didn’t get a glass of bubbly upon boarding (which I’m used to when booking business class on other flights), but otherwise it was a pleasant flight with lovely, helpful crew members and I enjoyed my meal.

Flight was canceled for a reason they knew hours before but did not mention. Next the gate chnage from 37 to 38 at least 10 times. Ridiculous.

It was just fine. I managed to make all my connection too sbut had trouble in Munich with no wheel chair and trouble trying to get help from the airport people to get to the other terminal for my flight. Finally a wonderful lady Amelia, helped me to make my flight connection Timon with zero time to spare.

Super experience. Earlier than schedule departure and arrival. Baggage handling was very good

Everything you need to know for your flight to Ontario

Cabin class types available on flights to Colorado

Cabin classes available on flights to Colorado. Prices are the lowest found on KAYAK over the last 7 days. Price and availability is not guaranteed.