$142 Find Cheap Flights from Ontario to Colorado

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Low seasonJanuary
High seasonAugust
Cheapest flight$142
Best time to beat the crowds with an average 0% drop in price.
Most popular time to fly with an average 2% increase in price.
Flight from Toronto Region of Waterloo Intl to Denver

Flights from Ontario to Colorado: the best tips from KAYAK users

Insights shared by verified travelers who flew the route from Ontario to Colorado 
Verified travelerFlew with Air CanadaYYZ-DENJul 2024
I only wished they had tv monitors. The flight and the crew were excellent!
F.Flew with United AirlinesYYZ-DENAug 2024
Make sure to check the airline delay flights rate and if you have important commitments choose another airline.
JoshuaFlew with Air CanadaYYZ-DENApr 2024
Toronto's customs was one of the faster experiences I've had. They opened four more lanes to expedite the process when the lane got too long, to ensure we would all get through within around 15 minutes. The public transportation within the city is also top notch, in my opinion.

FAQs for booking flights from Ontario to Colorado

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

    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 Ontario to Colorado.

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

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight from Ontario to Colorado 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 Ontario to Colorado?

    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 Ontario to Colorado 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 Ontario to Colorado?

    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 Ontario to Colorado 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 Colorado?

    Prices will differ depending on the departure airport, but generally, the cheapest airport to fly to in Colorado is Denver Intl Airport (DEN), with an average flight price of $267.

  • What is the cheapest day to fly to Colorado?

    Based on KAYAK data, the cheapest day to fly to Colorado is Wednesday where round-trip tickets can be as cheap as $478. On the other hand, the most expensive day to fly is Monday, where round-trip prices are $563 on average.

  • What is the cheapest time of day to fly to Colorado?

    The cheapest time of day to fly to Colorado is generally in the afternoon, when round-trip flights cost $384 on average. Morning departures are around 8% more expensive than evening flights, on average. The most expensive time of day to fly to Colorado is generally in the morning, which is peak travel time and where the average cost of a ticket is $537.

  • What is the cheapest flight to Colorado?

    The cheapest ticket to Colorado from Ontario found in the last 72 hours was to Denver, at $176 round-trip. The most popular route is Toronto Pearson Intl Airport (YYZ) to Denver (DEN) and the cheapest round-trip airline ticket found on this route in the last 72 hours was $176.

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

    The cheapest month for flights from Ontario to Colorado is September, when tickets cost $433 (return) on average. On the other hand, the most expensive months are December and February, when the average cost of round-trip tickets is $544 and $516 respectively.

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

    To get a below average price on the flight from Ontario to Colorado, you should book around 4 weeks before departure. For the absolute cheapest price, our data suggests you should book 10 weeks before departure.

  • How long is the flight to Colorado?

    An average nonstop flight from Ontario to Colorado takes 9h 58m, covering a distance of 1435 miles. The shortest route is Toronto Pearson Intl Airport (YYZ) to Denver (DEN) with an average flight time of 3h 34m.

  • What are the most popular destinations in Colorado?

    Based on KAYAK flight searches, the most popular destination is Denver (96% of total searches to Colorado). The next most popular destinations are Colorado Springs (3%) and Aspen (1%). Searches for flights to Vail (0%) and to Grand Junction (0%) are also popular.

Top 3 airlines serving from Ontario to Colorado

Need help choosing which airline to fly with from Ontario to Colorado? 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 8696 reviews
7.7Boarding
7.3Comfort
6.6Food
7.1Entertainment
8.1Crew
Airline reviews

The gate attendant let me walk right by her with a bag too big for the overhead compartment

10.0 ExcellentMarni, Apr 2025DEN - DRO
Read more United Airlines reviews

The gate attendant let me walk right by her with a bag too big for the overhead compartment

Plane temperature was comfortable (not to hot) when boarding and waiting for takeoff.

We tried to upgrade to economy premium but were told this was not possible as we had booked through United Airlines (and Air Canada was operating the flight). This seemed silly given there was ample space in economy premium. Additionally, we had to wait almost 1.5 hours upon arrival to taxi to the gate. Otherwise, the crew were very pleasant and passengers were friendly.

It was my first time with United Airlines and I would say it was very good experience and best of all the flights were on time. Will definitely fly with United Airlines next time.

headphone jack didnt work for the first flight and not much variety

Food choices were very limited. Taste of the dishes was average.

I liked all the informational texts. I always knew where to go and when .

Not as good as expected Air Can needs to improve totally rated on internet as worst

The flight was delayed, it took longer than anticipated because of weather, and they broke my luggage.

Received an email the night before showing that there would be seatback entertainment on our flight. We get on and there was no seatback entertainment. And then it was a scramble to try to set up the iPads for the kids before takeoff so they could watch something for the four hour flight.

Paid $35 and not able to access the internet at all.

Several delays. Next flight was worse. Did not arrive home until 2am PT

Very helpful ground crew after an earlier flight delay and being rebooked on a different flight.

Not very good , the stewardess were unfriendly and they don't like to be bothered. Cos was a night flight and they need to sleep.

Everything about the flight was lovely…We left early, arrived early, cabin crew were efficient and helpful. Flight was easy and most pleasant.

First world problems, but still… We were seated in first class and asked for a cocktail on a very short, 50 minute flight. After our drink order was taken, a half hour went by, and we noticed that every other person in the small plane had been served except for us. We got up to ask about it, the drinks finally came, then were taken away three minutes later since the flight was so short. Really strange situation, on the other hand, we were in Utah.

We missed our flight. The boarding pass had the wrong gate and by the time we received the text from Kayak, our flight was already gone. I’ll never use Kayak again and will go direct to the airlines in the future.

Boarding took forever, the plane was cramped and cold, and the seatbelt song came on constantly throughout the red eye flight with a loud pre-recorded message playing each time

Cabin felt crammed Snacks are lame But crew was super efficient getting us out on time despite delay

Flight was delayed bc of mechanical issue. New plane had different configuration so some seats had to be switched. They called all passengers who needed new boarding cards. They did not call us so we thought our seats were the same and fine. When we boarded they informed us our receipts had changed and we are now all sitting separate and in the back row. Both my daughters had meltdowns and started to cry and once we got on the flight, we figured out how we could sit closer to each other, but this was very upsetting.

My flight got delayed 5 times and then got cancelled eventually, I had to get a hotel and uber and pay for food for an extra night without any plans. It was a horrible experience, instead of Air Canada, I was flying with United .

I had a nice flight with free wifi. So I was able to message family members and stream music during my flight, which made the trip go by fast. I also enjoyed flying on there Airbus A220. The plane looked very new and it also got up to speed fast down the runway and didn't need much runway to get airborne.

Overall good experience. The flight from Toronto to Denver does not have entertainment - movies to watch.

Ensure prepaid food arrangements are appropriately understood by flight crew of who purchased and who did not

All was fine. Weather was a bit stormy, but nothing kayak can do about that! 😊

I paid for a comfort class seat and was seated in economy.

My plane was cancelled and had to be rebook for the evening was not happy.

The flight was cancelled and we had to rebook on Porter to make our cruise the next day. Air Canada has not compensated. We won’t be flying with them again. This is the second time this has happened. Also the return flight was delayed 2 hours who knows why.

Separated me and my wife and wife’s sister in far apart different seats even though I booked them all together. Just scams after scams to make us pay more. Worst airline

The only issues I have are the seats are very small and so is the overhead storage. You should mention that while booking flights. I had plenty of knee room but I am wider than my seat, and I am not fat at all. The Mitsubishi 900 models need to be upgraded to western size people. I do not know how a 300 pound woman fit into those seats. I had to continuously lean away from the aisle to keep people and flight crew from bumping into my shoulder. 3 hour flight so no entertainment or food, just snacks and a drink, which was no big deal. The buttery/garlic pretzels were pretty tasty.

Book cheap flights from Ontario to Colorado

Recent round-trip flight deals

5/22Thu
1 stopWestJet
22h 27mYYZ-DEN
5/28Wed
2 stopsWestJet
10h 20mDEN-YYZ
$225
5/22Thu
1 stopWestJet
15h 02mYYZ-DEN
5/28Wed
1 stopWestJet
8h 41mDEN-YYZ
$230
6/8Sun
1 stop
9h 52mYYZ-DEN
6/11Wed
1 stop
17h 01mDEN-YYZ
$300
6/13Fri
1 stop
8h 28mYTZ-DEN
6/20Fri
1 stop
10h 17mDEN-YTZ
$312
5/29Thu
1 stopUnited Airlines
6h 24mYYZ-COS
6/5Thu
1 stopUnited Airlines
13h 18mCOS-YYZ
$328
6/1Sun
1 stopUnited Airlines
15h 46mYUL-COS
6/14Sat
1 stopUnited Airlines
13h 56mCOS-YUL
$350
8/6Wed
2 stopsAir Canada
10h 38mYUL-COS
8/10Sun
2 stopsAir Canada
9h 26mCOS-YUL
$397
7/15Tue
nonstopAir Canada
4h 16mYUL-DEN
7/21Mon
nonstopAir Canada
3h 46mDEN-YUL
$441
6/19Thu
1 stopAmerican Airlines
18h 31mYUL-DEN
6/22Sun
1 stopAmerican Airlines
7h 49mDEN-YUL
$473
9/25Thu
1 stopAmerican Airlines
9h 25mYUL-DEN
9/28Sun
1 stopAmerican Airlines
6h 40mDEN-YUL
$474

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Recent one-way flight deals

5/23Fri
1 stopWestJet
14h 52mYKF-DEN
$142
6/15Sun
1 stopWestJet
14h 22mYYZ-DEN
$146
6/15Sun
1 stop
24h 18mYTZ-DEN
$164
6/15Sun
2 stops
23h 01mYYZ-DEN
$171
5/13Tue
2 stopsUnited Airlines
10h 33mYYZ-COS
$192
7/6Sun
1 stopUnited Airlines
15h 50mYUL-COS
$239
9/30Tue
1 stopAmerican Airlines
12h 45mYYZ-DEN
$241
6/30Mon
nonstopAir Canada
4h 16mYUL-DEN
$251
5/30Fri
2 stopsAmerican Airlines
14h 14mYYZ-DEN
$252
6/3Tue
nonstopAir Canada
4h 22mYUL-DEN
$256

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Last minute flights from Ontario to Colorado

Last minute flight, train and bus deals

5/4Sun
multi-stop
10h 14mYYZ-DEN
5/13Tue
multi-stop
8h 41mDEN-YYZ
$508
5/4Sun
multi-stop
10h 14mYYZ-DEN
5/14Wed
multi-stop
10h 11mDEN-YYZ
$515
5/4Sun
multi-stopUnited Airlines
7h 39mYYZ-COS
5/11Sun
multi-stopUnited Airlines
12h 06mCOS-YYZ
$522
5/5Mon
multi-stopWestJet
19h 18mYYZ-DEN
5/13Tue
multi-stopWestJet
8h 41mDEN-YYZ
$568
5/3Sat
multi-stopWestJet
9h 35mYYZ-DEN
5/14Wed
multi-stopWestJet
10h 11mDEN-YYZ
$653
5/4Sun
multi-stopUnited Airlines
21h 03mYYZ-DEN
5/11Sun
multi-stopUnited Airlines
18h 58mDEN-YYZ
$772
5/1Thu
multi-stopAmerican Airlines
11h 11mYUL-DEN
5/4Sun
multi-stopAmerican Airlines
9h 45mDEN-YUL
$1,065
5/1Thu
multi-stopAmerican Airlines
11h 11mYUL-DEN
5/4Sun
multi-stopAmerican Airlines
9h 45mDEN-YUL
$1,067
5/4Sun
nonstopAir Canada
4h 15mYUL-DEN
5/11Sun
nonstopAir Canada
3h 46mDEN-YUL
$1,158
5/1Thu
nonstopAir Canada
4h 22mYUL-DEN
5/2Fri
nonstopAir Canada
3h 46mDEN-YUL
$1,302

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Everything you need to know for your flight to Colorado

Cabin class types available on flights to Ontario

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

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