$127 Find Cheap Flights from Denver to Ontario

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from Denver to Ontario departing on 7/19. 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

KAYAK searches hundreds of travel sites at once for deals on flights to Ontario

 
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Denver to Ontario, as well as popular online travel agencies
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Denver to Ontario, as well as popular online travel agencies
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Cheap Flights from Denver to Ontario

Cheapest round-trip prices found by our users on KAYAK in the last 72 hours
Toronto
Toronto1 stop$405
Ottawa
Ottawa1 stop$434
London
London1 stop$451
Toronto
Toronto1 stop$405
Ottawa
Ottawa1 stop$434
London
London1 stop$451

Book Cheap Denver to Ontario Plane Tickets

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from Denver to Ontario that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.
Discover the best prices for you by selecting your travel dates on KAYAK.

Recent round-trip flight deals from Denver to Ontario

Sat, Aug 29 - Mon, Aug 31
WestJet Logo
12:15 pm - 11:45 pm
DEN
-
YUL
9h 30m
1 stop
WestJet Logo
8:00 pm - 11:20 am
YUL
-
DEN
17h 20m
1 stop
$347WestJet
Tue, Aug 11 - Mon, Aug 17
WestJet Logo
12:15 pm - 11:45 pm
DEN
-
YUL
9h 30m
1 stop
WestJet Logo
7:15 am - 11:20 am
YUL
-
DEN
30h 05m
1 stop
$360WestJet
Tue, Aug 11 - Mon, Aug 17
WestJet Logo
12:15 pm - 11:45 pm
DEN
-
YUL
9h 30m
1 stop
WestJet Logo
5:45 pm - 11:20 am
YUL
-
DEN
19h 35m
2 stops
$373WestJet
Fri, Aug 7 - Fri, Aug 21
WestJet Logo
12:15 pm - 7:05 am
DEN
-
YUL
16h 50m
1 stop
WestJet Logo
7:15 am - 11:20 am
YUL
-
DEN
30h 05m
1 stop
$374WestJet
Mon, Oct 5 - Wed, Oct 14
WestJet Logo
12:15 pm - 11:45 pm
DEN
-
YUL
9h 30m
1 stop
WestJet Logo
5:30 pm - 11:20 am
YUL
-
DEN
19h 50m
1 stop
$375WestJet
Fri, Sep 11 - Fri, Sep 18
Multiple Airlines Logo
12:15 pm - 11:45 pm
DEN
-
YUL
9h 30m
1 stop
Multiple Airlines Logo
10:35 am - 12:29 am
YUL
-
DEN
15h 54m
2 stops
$379Multiple Airlines
Tue, Aug 11 - Mon, Aug 17
WestJet Logo
12:15 pm - 11:45 pm
DEN
-
YUL
9h 30m
1 stop
WestJet Logo
5:30 pm - 11:20 am
YUL
-
DEN
19h 50m
1 stop
$388WestJet
Fri, Jul 31 - Sun, Aug 9
Air Canada Logo
11:30 am - 8:32 pm
DEN
-
YXU
7h 02m
1 stop
Air Canada Logo
5:40 am - 10:35 am
YXU
-
DEN
6h 55m
1 stop
$805Air Canada
Fri, Jul 31 - Sun, Aug 9
Air Canada Logo
11:30 am - 8:32 pm
DEN
-
YXU
7h 02m
1 stop
Air Canada Logo
5:40 am - 10:35 am
YXU
-
DEN
6h 55m
1 stop
$808Air Canada
Fri, Jul 31 - Sun, Aug 9
Air Canada Logo
7:16 pm - 2:52 pm
DEN
-
YXU
17h 36m
2 stops
Air Canada Logo
5:40 am - 10:35 am
YXU
-
DEN
6h 55m
1 stop
$811Air Canada
Booking Insights

KAYAK's insights & trends for Denver to Ontario flights

Get data-powered insights and trends into flights from Denver to Ontario to help you find the cheapest flights, the best time to fly and much more.

How much is a round-trip flight from Denver to Region of Ontario?

This analysis is based on the cheapest round-trip price found on KAYAK in the last 12 months by searching for a flight from Denver to Region of Ontario departing in October.

What is the cheapest Denver to Ontario flight route?

Data is based on round-trip flight searches on KAYAK over the past month.

The cheapest ticket to Ontario from Denver found in the last 5 days was to Toronto, at $427 round-trip. The most popular route is from 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 $427.

What is the cheapest time of day to fly to Ontario?

The average price for all round-trip flights from Denver to Ontario depending on the time of departure, clicked by users on KAYAK in the last 2 weeks.

The cheapest time of day to fly to Ontario is generally in the afternoon, when round-trip flights cost $702 on average. Morning departures are around 5% 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 $790.

Can I save money by flying with a layover from Denver to Ontario?

The average round-trip price for all non-stop flights, flights with one layover, and flights with two layovers for the route found by users searching on KAYAK in the last 2 weeks.

No, with an average price for the route of $622, prices are generally cheapest when you fly direct.

What is the cheapest month to fly from Denver to Ontario?

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from Denver to Ontario, removes the top 0.1% to account for outliers, and then takes the median of all values for each month.

The cheapest month for flights from Denver to Ontario is January, when tickets cost $129 (return) on average. On the other hand, the most expensive months are May and June, when the average cost of round-trip tickets is $244 and $236 respectively.

What’s the cheapest day of the week to fly from Denver to Ontario?

The average price of all round-trip flights from Denver to Ontario clicked on KAYAK for each day over the last 12 months.

If you are looking for a flight deal from Denver to Ontario, look for departures on Thursdays and avoid leaving on a Sunday, as it's usually the priciest day. When flying back from Ontario, Thursday is the cheapest day to fly and Sunday is the most expensive.

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

To calculate weekly average prices, KAYAK takes all prices for each week before departure over the last year for round-trip flights from Denver to Ontario, removes the top 0.1% to account for outliers, and then takes the average of all the values for each week.

To get a below average price on the flight from Denver to Ontario, you should book around 4 weeks before departure, which saves you about 55% compared to booking last minute. For the absolute cheapest price, our data suggests you should book 7 weeks before departure.

Good to know

Low seasonJanuary
Cheapest flight$127
Best time to beat the crowds but there is an average 6% increase in price.
Most popular time to fly and prices are also 25% lower on average.
Flight from Denver to Toronto Pearson Airport

FAQs - booking Ontario flights

  • How does KAYAK find such low prices on flights from Denver 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 Denver to Ontario.

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

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight from Denver 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 Denver 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 Denver 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 Denver 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 Denver to Ontario up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

Reviews of the top 4 airlines serving from Denver to Ontario

 
See real verified KAYAK customer reviews for airlines flying from Denver to Ontario. Airline scores are aggregated from all reviews left by passengers on KAYAK after flying with an airline. KAYAK doesn’t show reviews that are older than 5 years. Learn how KAYAK collects reviews.
Need help choosing which airline to fly with from Denver 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 8434 reviews
7.2Food
8.1Boarding
7.8Comfort
7.8Entertainment
8.5Crew
Airline reviews

Not really a “Delta” problem but worth mentioning: Boarding was a difficult process. TSA seemed understaffed and Pre-Check took longer than regular TSA. The supervisor was frazzled and yelled at travelers. Once through TSA, we had to put our carry-ons through another x-ray machine. Then queue up to board with both boarding pass and ID. Then, when we got to the stairs on the tarmac, we had to show our boarding pass again. Maybe this is just normal for Kona since the terminal is outdoors (but still a “secured” area).

6.0 GoodMary, Jun 2026
KOA - SEA
Read more Delta reviews

Not really a “Delta” problem but worth mentioning: Boarding was a difficult process. TSA seemed understaffed and Pre-Check took longer than regular TSA. The supervisor was frazzled and yelled at travelers. Once through TSA, we had to put our carry-ons through another x-ray machine. Then queue up to board with both boarding pass and ID. Then, when we got to the stairs on the tarmac, we had to show our boarding pass again. Maybe this is just normal for Kona since the terminal is outdoors (but still a “secured” area).

flight was delayed 4+ hours. there was really no understanding of why? weather? the last hour of delay was post boarding. pilot seat was broken. was that the real reason? nonetheless, long day of inconveniences.

Love me some Delta. One of the few airlines to recognize and support veterans. Easy boarding, flight was on time and arrived early and the flight attendants were excellent on this flight.

I thought the service was very nice and pleasant. There were no hiccups and no issues so overall a good experience.

Very good flight. Crew was great. No issues and we even arrived early.

The flights are constantly late anymore, and they won't even give you a glass of water on the plane. For years, they were able to do a service on this flight from Atlanta to Knoxville and Knoxville Atlanta now they say it's too short of a flight. You can't even get a quick drink of water.

Flight got canceled 4 times, missed my connecting flight due to delays, have to wait to go home tomorrow

Third flight in two months where the crew was not there. Comfort seating does not guarantee overhead bin space. Passengers with children are allowed on the plane first - if you are flying to and from Orlando, this means half the plane has boarded before you get on. And somehow all the bin space is taken up. 3 out of 5 flights have had issues with equipment or procedure. Some of these instances caused the flight to be delayed because of a "nuisance" light. One time it was a bag that had been brought on board but did not belong to anyone so we had to return to the gate. Last night we were told the "AC" on the plane doesn't work well and we're 10th for take off- because the crew was late - and that it will get cool when we're in the air. Not sure if this is usual, but I didn't think flight crew could jump seat in first class. Movie and TV selection has not been refreshed for several months- flying one to two round trips each month easily exhausts the list of content.

Great experience nice pilot very soft and easy landing and take off

We sat on the runway for over an hour before departure. That was unwelcome.

Very easy ! Use the kiosk and bag drop and right to security within 10 min

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 ...

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.

Food options were ok but the actual meal was terrible. On my way back, they simply said that there was no vegetarian option; somehow they struggled to get one meal and did not give me any breakfast at all which in my opinion was terrible. Never had such an experience in the recent years.

1didnt have wheel chair I ordered wheel chair in my ticket 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

Everything you need to know for your flight from Denver to Ontario

Information on your arrival and departure airports