$107 Find Cheap Flights from Colorado to Ontario

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Low seasonJanuary
High seasonJuly
Cheapest flight$107
Best time to beat the crowds but there is an average 15% increase in price.
Most popular time to fly and prices are also 3% 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 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 $226.

  • 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 $690. On the other hand, the most expensive day to fly is Monday, where round-trip prices are $788 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 $243 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 $716.

  • 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 $352 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 $352.

  • 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 August and April, when the average cost of round-trip tickets is $543 and $542 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 3 weeks before departure. For the absolute cheapest price, our data suggests you should book 24 weeks before departure.

  • How long is the flight to Ontario?

    An average nonstop flight from Colorado to Ontario takes 11h 27m, 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.

  • What are the most popular destinations in Ontario?

    Based on KAYAK flight searches, the most popular destination is Toronto (94% of total searches to Ontario). The next most popular destinations are Ottawa (5%) and Thunder Bay (0%). Searches for flights to London (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.
8.0
DeltaOverall score based on 7964 reviews
7.3Food
8.5Crew
7.9Comfort
8.2Boarding
7.9Entertainment
Airline reviews

I like for how they process during check in. It was very smoothly.

10.0 ExcellentAbdulla, Jun 2025CMH - JFK
Read more Delta reviews

I like for how they process during check in. It was very smoothly.

The flight was scheduled for 2:30 PM. Early in the morning we got a text message saying the flight was delayed and rescheduled for 3:00 PM. We got to the airport with that in mind. Then we got a message during check-in at the flight was rescheduled again for 2:30 PM. We almost missed our flight. In fact, our bags Were told that they would not make it. At the end, everything worked out. But it is very stressful.

Overall, aside from the baggage issue, it was as good as one expects.

Most aspects were good however if they assign boarding zones they ought to enforce them or why bother? My luggage from SAN-JFK-MAD was lost in NY so I without my main bag for two days upon arrival in Spain. They were helpful in tracking it and eventually delivered it to my hotel. The flub was because of a delay upon arrival in NYC. I had booked 2 1/2 hours between flights but we had to hold on the taxiway for an hour after landing while waiting for a clear gate which likely caused the baggage error.

I want to single out flight attendant Mitch who was in the Premium Economy section. When my wife’s hearing aide dropped through the cushion under the seat he was able to locate it and return it to her. Food was a different matter. Dinner was fine. Breakfast was another matter. They had a yogurt dish that the ran out of and the alternative was not very good according to those we talked to.

Excellent check-in. Crew was good. Excellent communication from flight deck.

Great overall. There was a bit of turbulence so they could only serve water because too much turbulence for the carts. Was glad they prioritized safety though

Excellent flight, the planes were newer, they did a nice job with boarding, great service overall.

Flight was delayed long enough that I was misding my connecting flight. The agents could not get me on a comparable flight, nor could they get me s Main Cabin seat I had paid for, nor could they get me on a comparable connecting flight. The gate agent would not issue meal vouchers, even though I was delayed over six hours! I had to spend over an hour and 15 minutes with customer service on the phone to See if they could get me on a better flight and get a meal voucher. Customer service was not helpful enough in trying to find alternate flights and it Ended up taking me 24 hours for a 12 hour trip!! Delta does not provide upgrades NOR will they even give you a pass for a few hours to their lounge. They claim that they do not issue daily passes to their lounge anymore. I call BS since this would be no extra cost to them to provide excellent customer service and give you a few hours to relax in comfort when you’re sitting in a crowded airport and your flight has been screwed up for that many hours.

Great service. Flight was delayed while we sat on the runway for a couple of hours. Weather related. Staff made is very bearable. The steward servicing the first class cabin was exceptional. Thank you! 💗

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

I do prefer to fly United and have always had excellent service, except for bad weather. Flights are on time and staff is alway curtious and helpful

We were delayed in Toronto on the tarmac for THREE hours with no clear indication as to why except that it was not a safety hazard. Pilot did apologize more than once but even he was unable to explain why exactly we were delayed. I overheard the stewards saying that the captain was very frustrated with the situation as well because he was not able to explain why except it had something to do with water supply or system on the aircraft and now we needed to wait for an engineer to approve the aircraft for flight. It was very frustrating and distressing as a passenger and we should have been given complimentary meals at the very least.

Overall poor for me I paid extra for seats with leg room and my regional flights exit row seats have less leg room then the others that's money that could have been saved and on my final flight home the flights air was not operating it was unbearably hot in the cabin I will be contacting United and filing a DOT complaint

Not only was the flight delayed more than 3 hours but also there was no internet or movies on the flight. It was Flair/Spirit quality of experience at Westjet prices

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.

We didn’t make the flight due to Delta’s check in line moving too slow.

The flight was ahead of schedule. A half glass of juice and a cookie is pathetic! No entertainment possibilities. Not even a plug-in for phone or IPad if you wanted to watch a downloaded movie. Back to flying Air Canada!

The flight was ahead of schedule. A half glass of juice and a cookie is pathetic!

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

The staff were the friendliest I have encountered in years. Absolutely great!

Plane changed to one with no entertainment system or ability to serve hot meals

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 was delayed but the real issue is how long we sat after boarding. Space very limited for an overnight flight and seatbacks didn’t recline so it was almost impossible to sleep.

The staff made sure I was comfortable, moved me to a better seat with more leg room

Somehow, my booking was under my preferred name instead of my legal name so they almost didn’t let me board the plane at LAX. This problem should have been notified to me when I was still in Toronto.

When arriving over 2 hours early to check k in at Charlotte airport I was told I would have to check my carry on ? Apparently the flight was full and may not be room. I was not given a choice and the agent was quite unpleasant about it. I am a senior amd was not comfortable me having to worry about my bag being lost vut it didn’t seem to bother him. There were lots and lots of people of all ages in line when we boarded with carryons and most larger than mine .the rest of my journey was pleasant vut this was totally unacceptable.

The layover was 6 PLUS hours and we were only given a $15.00 voucher. We missed our first activity in Quebec due to the delay.

Miserable staff as it was a late/delayed flight and crew wasn’t in the best spirits. Completely understood as neither was most of the passengers. Still unacceptable l.

It was a short flight, and no entertainment. That was not a problem for us, but there is no option for "not applicable". There was a bit of turbulence, so there was no food service.

the fact air Canada changed my flight from 850 PM to 815 AM with zero regard to the plans i made that last day, the cost i lost out on as things were non refundable amd shortening my first vacation in 7 years sickened me. when we purchase a service thats whats we expect. when we want to change the service we have to pay for that option but you do whatever you want . i called accessibility dept as i have a cpap and an implanted loop recorder first person said no problem just let security know you cant go thru scanners. then i got an email saying i had to fill out a fit to fly form . which again there was NO need to have that none. But that cost me money and time to have a doctor fill it out. then when i went to check in online i was declined i had to see a person at the airport instead. i couldnt get my boarding pass like everyone elseso here I was contacting air canada so I would have a easy travel experience and it ended up being a nightmare with more work for me, more cost and time. the flight itself was great the nightmare around it i will never subject myself to again. i tried to stick with supporting Canada but Air Canada was not worth supporting. very disappointed especially with a dept that is supposed to help disabled people not make an already challenging event not worth going thru at all.

Most courteous, helpful employees and all flights were on time.

2.5 hour delay sitting in the plane on the tarmac, you tell me how the experience was

Book cheap flights from Colorado to Ontario

Recent round-trip flight deals

8/20Wed
1 stopWestJet
10h 28mDEN-YUL
8/31Sun
1 stopWestJet
19h 54mYUL-DEN
$249
8/30Sat
1 stopWestJet
10h 28mDEN-YUL
9/2Tue
1 stopWestJet
19h 54mYUL-DEN
$252
7/7Mon
1 stopAir Canada
11h 14mDEN-YOW
7/15Tue
1 stopAir Canada
6h 21mYOW-DEN
$262
7/3Thu
1 stopAir Canada
7h 55mDEN-YOW
7/5Sat
1 stopAir Canada
6h 21mYOW-DEN
$302
7/9Wed
1 stop
8h 39mDEN-YYZ
7/16Wed
2 stops
16h 00mYYZ-DEN
$303
8/26Tue
1 stop
10h 28mDEN-YUL
8/29Fri
2 stops
17h 09mYUL-DEN
$305
7/3Thu
1 stopUnited Airlines
7h 17mDEN-YOW
7/5Sat
1 stopUnited Airlines
9h 12mYOW-DEN
$310
7/15Tue
1 stopUnited Airlines
6h 04mDEN-YOW
7/22Tue
1 stopUnited Airlines
7h 07mYOW-DEN
$320
7/31Thu
1 stopDelta
7h 33mCOS-YUL
8/7Thu
1 stopDelta
10h 37mYUL-COS
$413
8/20Wed
1 stopDelta
6h 48mCOS-YYZ
8/27Wed
2 stopsDelta
12h 21mYYZ-COS
$426

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Recent one-way flight deals

7/16Wed
1 stopWestJet
8h 39mDEN-YYZ
$107
8/14Thu
1 stopWestJet
10h 28mDEN-YUL
$108
7/1Tue
1 stopUnited Airlines
15h 09mDEN-YOW
$128
8/16Sat
2 stopsUnited Airlines
17h 42mDEN-YOW
$133
8/16Sat
1 stopAir Canada
7h 20mDEN-YOW
$135
9/29Mon
1 stop
16h 25mDEN-YYZ
$156
9/3Wed
2 stops
20h 23mDEN-YYZ
$160
6/30Mon
nonstopAir Canada
3h 46mDEN-YUL
$167
6/23Mon
1 stopDelta
6h 26mDEN-YYZ
$177
6/23Mon
1 stopDelta
7h 25mDEN-YYZ
$182

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Last minute flights from Colorado to Ontario

Last minute flight, train and bus deals

6/21Sat
nonstopAir Canada
3h 13mDEN-YYZ
6/30Mon
multi-stopAir Canada
8h 20mYYZ-DEN
$347
6/21Sat
nonstopAir Canada
3h 13mDEN-YYZ
6/30Mon
nonstopAir Canada
3h 40mYYZ-DEN
$348
6/22Sun
multi-stopWestJet
27h 03mDEN-YUL
7/16Wed
multi-stopWestJet
30h 27mYUL-DEN
$360
6/20Fri
multi-stopDelta
8h 23mDEN-YYZ
6/24Tue
multi-stopDelta
5h 41mYYZ-DEN
$410
6/23Mon
multi-stop
17h 06mDEN-YYZ
7/21Mon
multi-stop
15h 02mYYZ-DEN
$411
6/21Sat
multi-stopDelta
8h 14mDEN-YYZ
6/24Tue
multi-stopDelta
5h 41mYYZ-DEN
$421
6/23Mon
multi-stop
17h 06mDEN-YYZ
8/18Mon
multi-stop
9h 55mYYZ-DEN
$422
6/22Sun
multi-stopWestJet
27h 06mDEN-YKF
6/24Tue
multi-stopWestJet
17h 42mYKF-DEN
$682
6/21Sat
multi-stopUnited Airlines
6h 48mDEN-YUL
7/1Tue
nonstopUnited Airlines
4h 15mYUL-DEN
$927
6/21Sat
nonstopUnited Airlines
3h 10mDEN-YYZ
7/1Tue
multi-stopUnited Airlines
10h 12mYYZ-DEN
$1,018

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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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