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

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from Colorado to Ontario departing on 8/7. 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

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Good to know

Low seasonFebruary
Cheapest flight$123
Best time to beat the crowds with an average 11% drop in price.
Most popular time to fly and prices are also 2% lower on average.
Flight from Denver to Toronto Pearson Airport

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 40 flights per week. United Airlines also offers 40 flights per week, while Austrian Airlines follows with 13 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 $375.

  • 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 $670. On the other hand, the most expensive day to fly is Sunday, where round-trip prices are $816 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 $701 on average. Morning departures are around 4% 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 $785.

  • What is the cheapest flight to Ontario?

    The cheapest ticket to Ontario from Colorado found in the last 5 days was to Toronto Pearson Intl Airport, at $468 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 5 days was $468.

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

    The cheapest month for flights from Colorado to Ontario is June, when tickets cost $93 (return) on average. On the other hand, the most expensive months are April and January, when the average cost of round-trip tickets is $252 and $198 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 54% 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 101 direct flights each week.

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

    There are around 15 direct flights from within Colorado to Ontario every day. Most flights (60%) depart in the morning.

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

    Each week there are around 101 direct flights from within Colorado to Ontario. The most common day for departures is Monday, with 16% of flights taking off on this day.

  • How long is the flight to Ontario?

    An average nonstop flight from Colorado to Ontario takes 8h 20m, 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 101 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 (5%) and London (0%). 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.
7.8
DeltaOverall score based on 8407 reviews
7.2Food
7.8Entertainment
8.5Crew
7.8Comfort
8.1Boarding
Airline reviews

Gate agent showed up 20 minutes before boarding and was not at all friendly. Had to take this flight due to the one on the day before being cancelled and any later options were already full with long standby lists. Despite having paid for Delta Comfort seats, Delta did not allow me (or anyone) to choose their seat. The agent assigned them for everyone just prior to boarding. Self seat selection was allowed on the original flight. Flight staff was great - very friendly.

2.0 MediocreAnonymous, Jun 2026
RDU - LGA
Read more Delta reviews

Gate agent showed up 20 minutes before boarding and was not at all friendly. Had to take this flight due to the one on the day before being cancelled and any later options were already full with long standby lists. Despite having paid for Delta Comfort seats, Delta did not allow me (or anyone) to choose their seat. The agent assigned them for everyone just prior to boarding. Self seat selection was allowed on the original flight. Flight staff was great - very friendly.

Flight attendants were great. Cheerful, upbeat and friendly. Jet, in particular, was fantastic.

I have Precheck. Flew HPN to DEN and return this past weekend. Delta didn't attach my Precheck number to this trip. So it was waiting in general line especially in Denver. Unavailable.

Original flight was delayed, then cancelled and the gate staff did not expedite rebooking. Also, no instructions were given that a ticket number was needed before being called to facilitate rebooking. This could have been much more organized.

Be on time? When not on time a circling for over an hour offer more than 1 bag of chips to the passengers? It was a 7 hour flight by the time we got done.

Five hour delays every hour, I wish it were all at once

Flight delayed four separate times. I’m now one hour hours late to landing.

worst flight ever from Delta, it got delayed and kept on delaying..

Should never have had to go to Detroit from Orlando back to Tennessee!

Got rerouted from a straight flight from Orlando to Atlanta to Knoxville to a flight from Orlando to Detroit to Knoxville! Seriously!! Flight delay out of Detroit! Long day for what should have been a pretty easy travel day!

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

This planes staff was top tier. Everything went great and had a great flight home.

Destroyed my suitcase. Tired of talking about it. Cancelling my unite mileage plus account.

New plane was lovely. Crew customer service is always lax but expected. Kraft on time and arrived safely.

It was a short flight so I was expecting too much

Had a one hour delay due to mechanical issue. I didn’t think I’d be able to make my connecting flight, but they waited for me and greeted me when I arrived to help things run smooth.

O’hsre taxi and deboarding took 40 minutes. Needed 20 minutes extra time between connecting flights to avoid running through terminal.

Was great in general, try to respect time and excuses when slight changes have been made, appreciated!

Really hard landing... as in slammed into the runway then hit the brakes really hard ...

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.

Westjet never disappoint always terrible small plane ,crowded cheap snack if you can call it snack

Westjet was late and we missed our connecting flight with Cathay. Had to wait 8 hours. Westjet only allows 1 checked in baggage for international flights- it’s always been 2. Canada allows only 1 sandwhich bag size full off small liquids. Everything else will be tossed. Awful trip. Will never fly west jet or go to Toronto to connect flights!

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.

Flight was overbooked and seats assigned to multiple passengers. Delay 1 hour to sort out.

Good but I don’t received my bags yet is been 5days still no update

It was a short flight so, everything went smoothly and we got to where we needed to be safely.

No TV on the flight. The charging outlet was not working. No food, even a sandwich. The served orange was poor quality.

Selected seats 5 months prior to date. Had email confirmation and seats were not honoured. Family did not sit together

They did not let us board because one member needed a transit visa, which was not evident at the time of ticket purchase.

I was charge a baggage checking fee $68!! I volunteered to check my duffle bag which usually goes under my seat!

I did not like anything because the flight was cancelled yesterday and I did not get to arrive on time in Toronto as I was rebooked with another airline. This caused me to be really stressed out as I am an individual with back injury and to be forced to stay longer in an airport to accommodate a change of airline and the transfers associated with it Due to this I am probably not going to book through your website to eliminate this potentially chaos in the future

shittiest airline in the hemisphere. To improve - start thinking you're flying people, not cattle

Easy boarding, inflight refreshments came on time and comfortable seat

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.