Find cheap flights from Colorado to Ontario from $88

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight departing on 8/16. 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.
Round-trip
1 adult
Economy
0 bags
Thu 7/6
Thu 7/13

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Good to know

Low season

July

High season

May

Cheapest flight

$88

Average price round-trip

$474

Good deal round-trip

$230

Good deal one-way

$111
Best time to beat the crowds with an average 6% drop in price.
Most popular time to fly with an average 14% increase in price.
Flight from Denver to Toronto Pearson Airport
(avg. price over the last 2 weeks)
or less
or less

FAQs for booking flights from Colorado to Ontario

Top 5 airlines serving from Colorado to Ontario

Scores according to KAYAK customer reviews
7.9
DeltaOverall score based on 29358 reviews
78comfort
85crew
81overall
75food
81boarding
78entertainment
Airline reviews
Pros: "That i was able to watch movies, snacks were provided and water"
Cons: "Nothing really!"
Read more about Delta
Pros: "That i was able to watch movies, snacks were provided and water"
Cons: "Nothing really!"
Pros: "The seats are not fabulous the crew was"
Cons: "They did a good job keeping us informed When we got really delayed"
Pros: "Crew was very pleasant. Boarding and deplaning was smooth and easy!"
Pros: "On a quick 40 minute flight they still managed riu server coffee, water and snacks."
Pros: "Availability of WiFi, a charging port and media options puts Delta a step (or two) ahead of their competitors. The professionalism of the crew, as well as the complimentary food/beverage options are also excellent."
Cons: "Not the airlines fault, but my 6’4” frame doesn’t fit very well in a middle main cabin seat."
Pros: "The flight landed early. Check-in staff were great."
Cons: "Boarding was a debacle. Flight was oversold. Passenger had trouble boarding when their group was called."
Pros: "We arrived eventually."
Cons: "Flight delayed three hours. Payed extra for an earlier flight. Very disappointing."
Pros: "There was an available seat next to me"
Cons: "I had to walk from one end of Minneapolis airport to the other end all within 35 mins to catch a connecting flight, tram was not in service. Not fun!!!"
Pros: "The crew was amazing. Kat and the other stewards were very friendly."
Cons: "Maybe the option for free upgrade to first class if flight is not full??"
Cons: "Delays were unfortunate, but the gate area at LaGuardia was way too crammed, hardly any seats, and poorly organized"

At the gate I got bumped from my reserved aisle seat to a window. Not a huge deal for a one-hour flight, but the "free seat reservations" are indeed "free" but not "reservations".

Westjet really prides themselves on friendly service and they deliver!

Pros: "no"
Cons: "I was not on this flight as a mistake was made by either Kayak or WestJet. I was not refunded my money which I think is unfair."
Pros: "Very attentive, friendly and efficient flight attendant. Smooth flight. Informative captain."
Pros: "I like that my original flight was rescheduled but I needed to arrive in Vancouver for my connection so I'm happy they moved me to an earlier flight. Very accommodating!-"
Cons: "Entrainment on flight"
Pros: "Crew was great."
Cons: "Communication as to why we were promoted to premier seats and service."
Pros: "The Westjet app took forever to download on my phone AND my husband was unable to download it ... made for a long flight without entertainment. Also, the crew didn’t come off welcoming or inviting."
Pros: "On-time flight, satisfactory crew."
Cons: "Seat felt cramped (not helped by overweight guy next to me), plane was warm with very mediocre airflow, window seat was missing window."
Pros: "Member of the crew was not too helpful. Despite my malfunction"
Cons: "Customer service. Understanding customer needs and provide best possible travel experience."
Cons: "For customers without hand held devices, there are no options for in-flight entertainment."

The flights were running behind causing a missed connection. Otherwise good experience

Pros: "Crew was amazing, seats were comfortable. Only negative is out of your control - bad weather in DFW held up departure 5-6 hours. Much of that was on the plane, but crew kept us notified. We had to return to the gate and wait another couple of hours. Awful trip, but not your fault. What I was surprised by was no comp hotel, and the discounts were not rally good discounts."
Cons: "Most of my issues were ATC problems, not AA. The AA personnel kept us informed, etc. The one thing you can control is hotels if delayed to the point of missing all connection until the next afternoon. I understand not compi9ng BUT, when google maps shows better rates at local hotels than your "discount" program, that's sad."
Pros: "Flying portion was fine."
Cons: "Flight delayed for mechanical issues.... then upon landing trapped in cabin filled with exhaust then again trapped in a locked hallway."
Pros: "Great crew"
Cons: "Stop sending rental car emails with cheap prices and then I try to reserve a car and the price is doubled"
Pros: "Pilot did great job, superb smooth landing."
Cons: "The two male flight attendants could have been a bit more friendly."
Cons: "If we had access to the WiFi to watch shows earlier like United does, that would be nice."
Pros: "Honestly, nothing!!"
Cons: "Everything. This airline has disappointed me for the last time."
Pros: "Crew was nice and made sure we were all comfortable before taken off :)"
Cons: "I was thirsty on the way back but we were not offered anything to drink so I waited till we landed to buy a drink, other then that was very enjoyable. Plan on using America airlines again"
Cons: "Old aircraft ...what’s with the non-assignment of seats until the last minute unless you pay extra !"
Pros: "liked the crew, but didn't know that we would have to check our bags, since the plane was small & had no overhead. Also, I wish I would have been told ahead of time, that I would have to check my bag again going home, even though the plane did have overhead space. Other than that, I love AA!"
Cons: "I didn't get very good instructions about picking up my carry on bag plane side. I was told to go to the baggage claim instead by a staff member when I came out of the plane, but this was wrong, so I ended up waiting a very long time for them to bring me my carry on bag to the baggage claim."

They ran out of food entree and the other option was pork which many people don’t eat.

During boarding, the crew told us there was new room left in the overhead bins, so carry-ons that didn't fit under the seat needed to be checked. Barely half the passengers had boarded at that point. I left my carry-on case outside the plane for checking. When I got on the plane, I saw there was still plenty of space in the overheads, so I went back and got my case. Another complaint, there was literally no entertainment of any sort on this plane. No screens for movies, no headphone jacks for music, nothing. I could understand if it was a an hour-long commuter flight, but it was 3+ hours.

4 hour delay that caused me to miss my connection. Couldn't get changed to another flight until arrival. Instructions for checking in for the first flight were wrong. There is no Air Canada counter in OKC to check in with.

Cons: "Food had little taste. Movies were not that current and selection was sparse"
Pros: "Entertainment options"
Cons: "My wife’s screen did not work. The pitch between the seats was too narrow for a transatlantic flight. Older plane that needed to be cleaned and updated."
Pros: "Cabin crew were terrific!"
Cons: "The unfortunate delay of our flight. And the entertainment systems seems to be getting old. What I mean is that it is by todays standard very very slow to switch between menus etc. And in some cases did not display all the menu content."
Pros: "very nice crew"
Cons: "plane was too small and there was 1.5 hour delay departing"
Cons: "Late. Wifi on the aircraft but didn’t work. Inflation GHY service suspended due to reported turbulence."
Pros: "great seating and food. service was excellent"
Cons: "low resolution screen makes a movie not enjoyable boarding was mediocre, we arrived late and the gate didnt know we were coming. AirCanada had already rebooked me for flight 28h later..which was ridicules. Immediate compensation was the upgrade from Premium to First. Thank you."
Cons: "i got to the airport 2.5 hours befor my flight to play it safe and waited at the check in for about a hour befor a air canada employe even showed up. vary poor service on the airlines part i will never fly with air canada again."

It never happened. Snow storm. Flights cancelled. Got Covid somewhere along the air travel.

Cons: "If the airlines was able to help finding my pierce that was missed at the security or the craft"
Pros: "There was nothing I liked. The plane was an hour late and nearly missed my connection."
Pros: "Just another 4 hour delay featuring United. By the time we took off the storm in Toronto had started and it completely ruined my plans."
Cons: "Be on time"
Cons: "My son was flying on United from Colorado Springs to Denver, then on to Seattle for Thanksgiving. He rushed through as quickly as he could, but the door to the place was closing and it left 10 minutes early. United recorded him as a 'No Show', and there policy now is to cancel the entire ticket is you miss any segment of a round trip ticket. Thus, his entire $900 was forfeited, he couldn't even pay a change fee to catch a later flight. I hate American, and now I hate United just as much. These airlines shills have been allowed to go out of business when they last filled for bankruptcy. We fly in quite a few international airlines, and outside of Alaska, Jet Blue and Delta, maybe Southwest, US carriers are absolutely bottom of the barrel and it's clear that their employees don't care whatsoever. Will never book again in United or American. I'll try Amtrak before either of those carriers."
Pros: "Crew worked hard under difficult circumstances but flight was not well equipped"
Cons: "First we boarded and then had to deviate and move to a different delayed flight. No head sets, tv did not work , seat was very uncomfortable."
Cons: "The plane was old and tired. The seats are just a step up from a park bench. There was virtually no entertainment system to speak of."
Cons: "Roomier Seats more isle space and comfortable seating. Better head sets"
Pros: "It’s ok. The airplane is not comfortable. It’s old and small"
Cons: "N/a"
Pros: "Cabin crew was friendly."
Cons: "United 737-800 seats are cramped. The flight was severely delayed due to weather, and United did not do well in communicating that well. We had to wait 38 minutes after arriving in Toronto for baggage to start arriving in the baggage hall. United did not provide customs cards prior to arrival."

Book cheap flights from Colorado to Ontario

Recent round-trip flight deals

8/18Fri
nonstopAir Canada
3h 18mDEN-YYZ
8/21Mon
nonstopAir Canada
3h 35mYYZ-DEN
$259
8/16Wed
1 stopMultiple Airlines
27h 30mDEN-YYZ
8/23Wed
1 stopMultiple Airlines
10h 10mYYZ-DEN
$282
9/21Thu
1 stopMultiple Airlines
23h 53mDEN-YYZ
9/25Mon
1 stopMultiple Airlines
9h 13mYYZ-DEN
$289
9/21Thu
1 stopMultiple Airlines
23h 53mDEN-YYZ
9/25Mon
1 stopMultiple Airlines
9h 10mYYZ-DEN
$297
9/15Fri
1 stopMultiple Airlines
13h 05mDEN-YOW
9/18Mon
1 stopMultiple Airlines
19h 07mYOW-DEN
$298
9/1Fri
1 stopMultiple Airlines
20h 06mDEN-YYZ
9/8Fri
1 stopMultiple Airlines
9h 13mYYZ-DEN
$300
7/4Tue
1 stopMultiple Airlines
16h 03mDEN-YYZ
7/25Tue
1 stopMultiple Airlines
17h 26mYYZ-DEN
$303
8/4Fri
2 stopsMultiple Airlines
24h 19mDEN-YYZ
8/8Tue
1 stopMultiple Airlines
17h 26mYYZ-DEN
$304
9/15Fri
1 stopMultiple Airlines
20h 06mDEN-YYZ
9/18Mon
1 stopMultiple Airlines
9h 13mYYZ-DEN
$312
9/13Wed
nonstopAir Canada
3h 18mDEN-YYZ
9/16Sat
nonstopAir Canada
3h 35mYYZ-DEN
$405
6/28Wed
nonstopAir Canada
3h 18mDEN-YYZ
7/5Wed
nonstopAir Canada
3h 35mYYZ-DEN
$406
6/21Wed
1 stopAir Canada
13h 38mDEN-YOW
6/26Mon
1 stopAir Canada
16h 20mYOW-DEN
$456
9/22Fri
1 stopWestJet
8h 37mDEN-YHM
9/24Sun
1 stopWestJet
9h 22mYHM-DEN
$471
9/22Fri
1 stopWestJet
8h 34mDEN-YKF
9/24Sun
1 stopWestJet
8h 22mYKF-DEN
$473
9/21Thu
1 stopWestJet
8h 37mDEN-YHM
9/25Mon
1 stopWestJet
23h 22mYHM-DEN
$481
10/26Thu
1 stopDelta
7h 57mCOS-YYZ
10/29Sun
1 stopDelta
8h 21mYYZ-COS
$487
9/15Fri
1 stopWestJet
8h 37mDEN-YHM
9/18Mon
1 stopWestJet
23h 22mYHM-DEN
$487
7/5Wed
1 stopUnited Airlines
14h 03mCOS-YYZ
7/12Wed
2 stopsUnited Airlines
10h 16mYYZ-COS
$497
10/26Thu
2 stopsAmerican Airlines
9h 04mCOS-YYZ
10/29Sun
2 stopsAmerican Airlines
14h 57mYYZ-COS
$577
7/5Wed
2 stopsAmerican Airlines
26h 12mCOS-YYZ
7/12Wed
2 stopsAmerican Airlines
19h 41mYYZ-COS
$606

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Recent one-way flight deals

8/16Wed
1 stopMultiple Airlines
27h 30mDEN-YYZ
$88
8/23Wed
1 stopMultiple Airlines
27h 30mDEN-YYZ
$90
8/28Mon
1 stopMultiple Airlines
25h 30mDEN-YYZ
$107
8/23Wed
1 stopMultiple Airlines
10h 40mDEN-YHM
$110
7/26Wed
1 stopMultiple Airlines
10h 28mDEN-YHM
$123
7/5Wed
1 stopMultiple Airlines
22h 18mDEN-YYZ
$139
7/5Wed
1 stopMultiple Airlines
22h 18mDEN-YYZ
$140
7/26Wed
1 stopMultiple Airlines
21h 54mDEN-YYZ
$142
8/2Wed
1 stopMultiple Airlines
21h 54mDEN-YYZ
$143
7/4Tue
1 stopMultiple Airlines
16h 03mDEN-YYZ
$146
6/28Wed
nonstopAir Canada
3h 18mDEN-YYZ
$185
7/13Thu
nonstopAir Canada
3h 18mDEN-YYZ
$191
7/4Tue
nonstopAir Canada
3h 18mDEN-YYZ
$200
7/3Mon
nonstopAir Canada
3h 18mDEN-YYZ
$209
9/12Tue
1 stopDelta
8h 49mDEN-YYZ
$213
8/6Sun
1 stopUnited Airlines
8h 13mDEN-YOW
$293
7/10Mon
2 stopsAmerican Airlines
22h 08mCOS-YYZ
$308
7/13Thu
1 stopUnited Airlines
7h 52mCOS-YYZ
$318
9/24Sun
1 stopWestJet
8h 37mDEN-YHM
$331
9/24Sun
1 stopWestJet
8h 34mDEN-YKF
$331

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Flights to Ontario

Return flight deals:

Ontario - Colorado

Cabin classes:

$1,627
$1,345
$311

Browse origins:

$1,402
$241
$1,748
$605
View more