$168 Find Cheap Flights from Colorado to Ontario

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Low seasonJanuary
Cheapest flight$168
Best time to beat the crowds but there is an average 16% increase in price.
Most popular time to fly with an average 16% increase in price.
Flight from Denver to Ottawa

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?

    Air Canada connects Colorado to Ontario with 28 flights per week. United Airlines also offers 28 flights per week, while Austrian Airlines follows with 14 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 78% 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 $346.

  • 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 $680. On the other hand, the most expensive day to fly is Sunday, where round-trip prices are $820 on average.

  • 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 6% 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 $718.

  • 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 $331 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 $331.

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

    The cheapest month for flights from Colorado to Ontario is February, when tickets cost $338 (return) on average. On the other hand, the most expensive months are April and May, when the average cost of round-trip tickets is $542 and $541 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 56% compared to booking last minute. For the absolute cheapest price, our data suggests you should book 25 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 74 direct flights each week.

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

    There are around 11 direct flights from within Colorado to Ontario every day. Most flights (81%) depart in the morning.

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

    Each week there are around 74 direct flights from within Colorado to Ontario. The most common day for departures is Monday, 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 06m, 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 05m.

  • 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 74 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 (95% of total searches to Ontario). The next most popular destinations are Ottawa (4%) 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 7977 reviews
8.5Crew
7.3Food
7.9Comfort
7.9Entertainment
8.2Boarding
Airline reviews

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

4.0 Okaypuravi, Aug 2025LGA - STL
Read more Delta reviews

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

Nothing special. The crew never went out of their way for anything.

Three seats in first class were broken and while they were able to still acommodate us it was looking very touch and go and they had others they could not acommodate

Mechanic delay in addition to a 2 hour change in takeoff time was frustrating.

Delayed due to thunderstorms and no in-flight service due to rough weather — both of which are out of Delta’s control. Flight was good overall.

The flight attendants in SLC were rude. I arrived 40 minutes early to gate. Ticket said I needed check in for seat assignments and tried check in and attendants said they weren’t doing it. And proceeded to never call me to give me a ticket so when time to board I received the very last seat. Please relay to employees to do their job better..,

On this flight I felt the food offering was not as complete as on previous flights. The tomato salad was a bit off and there was nothing additional such a bread or butter. The breakfast was only one option, so you either ate what they had or ate nothing. The crew was efficient, but most seemed frustrated throughout the flight. The flight arrived early and was obstacle-free, so I’m overall quite happy, but the shine in the rest of the experience just wasn’t there.

The seats got pretty uncomfortable pretty fast. The armrests are bigger than on other planes, so I had less room in the actual seat. My butt hurt by the end of the flight. :/ comfort was the primary issue. The crew were fantastic!

I believe that a four-hour trip should have a meal. Delta had none.

Great flight with Delta! Boarding was quick and easy, the amenities were solid, and the plane was in great shape. The flight attendants had a fun, lively energy while staying professional. All in all, a smooth trip — even managed to catch up on some rest. Thanks, Delta!

I had no checked baggage but was required to hand over carry on baggage at the door of the plane. There was a lot of overboard space in the plane and I was one of the last ones. I ran to get my carry on but it was gone. I was given back at the plane door in Toronto, so the wait was not as long as it would have been at the carousel.

the delay for 3 hours was understandable due to weather conditions but the flight should’ve provided some on flight compensations or at least provide more food.

I never flew. Flight was canceled. DIA worst airport in the country. Avoid at all costs.

Flight was actually on Air Canada. The flight itself was fine. Nothing special. Food was pretty pathetic except for cookies. They offered plenty of food and drinks but just wasn't very good. Even for airline food.

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 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.

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

I booked my flight months ago, and checked-in online about 12 hours before the flight. I received an email confirmation of check-in. I had no subsequent communication from Air Canada after my original booking. After arriving at the airport three hours before the flight, as instructed, I waited 90 minutes for an agent to appear to check my bag. I was informed that my flight had been canceled many weeks before, and that flight was no longer being run!! I showed a copy of my check-in confirmation, but no explanation could be found. I was placed on standby for the next flight and the connection. Luckily, those flights were not full and I arrived at my destination. I double checked my email, but I received no update about the flight from Air Canada until the day of the flight.

I was forcefully re-routed to another destination and was delayed a total of 8hours. I have still not received my bags, no one is taking responsibility. The agents at the airport lied to me that I will get to my destination same time as my previous flight where I was forcefully re-routed from.

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.

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