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ONT - DEN

Find cheap flights from Ontario to Denver from £67

This is the cheapest return flight price found by a KAYAK user in the last 72 hours by searching for a flight from Ontario to Denver departing on 24/5. 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
0 bags
Tue 4/6
Tue 11/6

Search hundreds of travel sites at once for deals on flights to Denver

 
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Ontario to Denver, 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 Ontario to Denver, as well as popular online travel agencies
In the last 7 days, travellers have searched 43,369,418 times on KAYAK, and here's why:

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Cheap flight deals from Ontario to Denver (ONT-DEN)

Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from Ontario to Denver 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 and deals for you by selecting your travel dates.
Choose your dates
00:59 - 04:20ONT-DEN
2h 21mdirect
22:37 - 23:59DEN-ONT
2h 22mdirect
£67Frontier
Find Deal
Fri, 24 May - Fri, 31 May
08:29 - 11:51ONT-DEN
2h 22mdirect
22:37 - 23:59DEN-ONT
2h 22mdirect
£107Frontier
Find Deal
Sat, 25 May - Fri, 31 May
13:20 - 19:16ONT-DEN
4h 56m1 stop
18:10 - 23:43DEN-ONT
6h 33m1 stop
£156Delta
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Tue, 4 Jun - Wed, 5 Jun
05:45 - 12:07ONT-DEN
5h 22m1 stop
18:36 - 23:42DEN-ONT
6h 06m1 stop
£161Delta
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Tue, 4 Jun - Tue, 11 Jun
06:00 - 15:07ONT-DEN
8h 07m1 stop
16:06 - 23:58DEN-ONT
8h 52m1 stop
£163Alaska Airlines
Find Deal
Tue, 4 Jun - Tue, 11 Jun
05:45 - 12:07ONT-DEN
5h 22m1 stop
18:36 - 23:42DEN-ONT
6h 06m1 stop
£166Delta
Find Deal
Sat, 1 Jun - Sat, 8 Jun
06:00 - 15:07ONT-DEN
8h 07m1 stop
06:00 - 19:14DEN-ONT
14h 14m1 stop
£197Alaska Airlines
Find Deal
Tue, 4 Jun - Wed, 5 Jun
05:15 - 08:32ONT-DEN
2h 17mdirect
19:30 - 20:48DEN-ONT
2h 18mdirect
£214United Airlines
Find Deal
Sun, 23 Jun - Sat, 29 Jun
13:45 - 19:39ONT-DEN
4h 54m1 stop
15:40 - 22:45DEN-ONT
8h 05m2 stops
£363United Airlines
Find Deal
Sat, 13 Jul - Tue, 16 Jul
06:45 - 11:28ONT-DEN
3h 43m1 stop
05:00 - 11:47DEN-ONT
7h 47m2 stops
£713American Airlines
Find Deal
Sat, 25 May - Fri, 31 May

Flights from Ontario to Denver - Travel Insights & Trends

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

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

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for flights from Ontario to Denver, 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 Ontario to Denver is April, where tickets cost £155 on average. On the other hand, the most expensive months are June and March, where the average cost of tickets is £222 and £214 respectively.

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

To calculate daily average prices, KAYAK takes all prices for each day before departure over the last year for flights from Ontario to Denver, removes the top 0.1% to account for outliers, and then takes the average of all the values for each month.
To get a below average price on the flight from Ontario to Denver, you should book around 3 weeks before departure. For the absolute cheapest price, our data suggests you should book 87 days before departure.

Which airlines provide the cheapest flights from Ontario to Denver?

The cheapest price for the route for each airline clicked by KAYAK users in the last 72 hours.
The best deals for a one-way ticket found by KAYAK users over the last 3 days were on Frontier (£72) and Delta (£78). The cheapest round-trip tickets were found on Frontier (£67) and Delta (£156).

Which airlines fly most frequently between Ontario and Denver?

Southwest connects Ontario to Denver up to 5 flights per day, followed by United Airlines (3 flights per day), and Frontier (2 flights per day).

Which airlines fly direct between Ontario and Denver?

Airline and price data is aggregated from results in KAYAK’s search results from the last 2 weeks for flights from Ontario to Denver.
There are 3 airlines that fly direct from Ontario to Denver. They are: Frontier, Southwest and United Airlines. The cheapest price of all airlines flying this route was found with Frontier at £161 for a one-way flight. On average, the best prices for this route can be found at Frontier.

How many flights are there between Ontario and Denver per day?

Each day, there are between 7 and 14 nonstop flights that take off from Ontario and land in Denver, with an average flight time of 2h 16m. The most common departure time is 05:00 and most flights take off at night. Each week, there are 77 flights. The most frequent day of departure is Tuesday, when 18% of all weekly flights depart. The fewest flights depart on a Saturday.

Which cabin class options are there for flights between Ontario and Denver?

The average price of flights for each cabin class for the route found by users searching on KAYAK over the last 2 weeks.
There are 3 cabin class options for the route. These are First, Business and Economy. Perform a search on KAYAK to find the latest prices and availability for all cabin fares, which differ across airlines.

How long does a flight from Ontario to Denver take?

The average direct flight takes 2h 17m, covering a distance of 817 miles.

What’s the earliest departure time from Ontario to Denver?

Early birds can take the earliest flight from Ontario at 00:44 and will be landing in Denver at 04:04.

What’s the latest departure time from Ontario to Denver?

If you prefer to fly at night, the latest flight from Ontario to Denver jets off at 22:23 and lands at 01:45.

Good to know - Cheap tickets from Ontario to Denver

Low season

January

High season

July

Cheapest flight

£67
Best time to beat the crowds (14% less expensive on average)
Most popular time to fly (18% more expensive on average)
Flight from Ontario to Denver

When to book flights from Ontario to Denver

Are your dates flexible? Find out the best times to travel from Ontario to Denver based on our flight data from the last year. Discover the cheapest month and even day to fly.
Estimated return price
KAYAK looks at all historical flight data for each date to provide a predicted price for one-way trips or returns with a duration up to 40 days. While we try to provide actual minimum prices for each date, some prices are predictions and actual prices may differ.

FAQs for booking flights from Ontario to Denver

  • What are the transit options at Denver International Airport (DEN)?

    There is a large network of transit options that connect to Denver International Airport (DEN). You can use the airport rail serving the eight stations which runs regularly every 15min during the day and every 30min at night. Also, you can opt for ground transportation such as hotel shuttles, taxis, ride shares, and rental car shuttles. However, if you are in a hurry, the most convenient option is to use a taxi.

  • Can I exchange my foreign currency at Denver International Airport (DEN)?

    Denver International Airport (DEN) has three global money exchange locations. They are located in Gates A, B, and Jeppesen Terminal Level 5. You can also use the airport exchange kiosk, although they have the worst exchange rates.

  • What transportation option is available to Ontario Airport (ONT)?

    There are many ways you can get to Ontario Airport (ONT) from Ontario City Center. Public transits offer cheap and easy travel although takes longer to arrive at the airport. The station is right within ONT for easy passenger access. There is also the use of airport shuttles to provide transportation to passengers. Alternatively, you can use a taxi, which is the fastest way to get to the airport.

  • Are there nursing suites at Denver International Airport (DEN)?

    There are various options of nursing suites for passengers with kids at Denver International Airport (DEN). They are located at each of DEN’s concourses, offering excellent security and a peaceful environment to nurse after a long flight. Also, the suites are available throughout the day and night.

  • What is the cheapest flight from Ontario to Denver?

    In the last 3 days, the lowest price for a flight from Ontario to Denver was £90 for a one-way ticket and £84 for a return.

  • Which airports will I be using when flying from Ontario to Denver?

    Ontario and Denver are both served by 1 main airport. You will leave Ontario from Ontario and will be arriving at Denver Intl.

  • Which airlines offer Wi-Fi service onboard planes from Ontario to Denver?

    All the following airlines offer inflight Wi-Fi service on the Ontario to Denver flight route: Delta, American Airlines, Alaska Airlines, JetBlue, Aeromexico, and British Airways.

  • Which aircraft models fly most regularly from Ontario to Denver?

    The Airbus A320neo is the aircraft model that flies most regularly on the Ontario to Denver flight route.

  • Which airline alliances offer flights from Ontario to Denver?

    Star Alliance is the only airline alliance operating flights between Ontario and Denver.

  • On which days can I fly direct from Ontario to Denver?

    There are direct flights from Ontario to Denver on a daily basis.

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

    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 Denver.

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

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

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional return ticket. You could then fly to Denver with an airline and back to Ontario with another airline.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Ontario to Denver?

    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 to Denver from Ontario up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

See more FAQs

Top tips for finding a cheap flight from Ontario to Denver

  • Looking for a cheap flight from Denver to Ontario? 25% of our users found flights on this route for £47 or less one-way.
  • If you are flying out of Ontario Airport (ONT) and need to park, you will find various parking spots. There are long and short-term parking options depending on how long you want to park. The parking stalls are open throughout to every passenger who wishes to park offering the ultimate convenience. They are located in each terminal providing valet, premium, and general parking options.
  • When flying from Ontario Airport (ONT), it is recommended that you arrive at least 2h earlier before your scheduled flight. It is vital to consider the time you will take when checking in at the airport, getting boarding passes, and passing through security checks. Luckily, the Ontario Airport (ONT) waiting time is improving to excellent staffing and screening options.
  • There are multiple power stations in all terminals when you get to Denver International Airport (DEN) and need to work. The stations are well-equipped making it comfortable to work at your convenience.
  • With multiple lounges at Denver International Airport (DEN), passengers can take advantage of the services and refuel when waiting for the next flight or shuttle bus. All the lounges are easily accessible as they are located near passenger departures.
  • If you are having an early morning flight and looking for accommodation, there are various hotels near Ontario Airport (ONT) offering excellent services like free shuttle transfer to the airport. These hotels include Double Tree by Hilton Hotel located 0.9 miles from the airport and Holiday Inn Ontario Airport, which is around 0.7 miles from the airport.
See more tips

Prefer to fly direct from Ontario to Denver?

Find which airlines fly direct from Ontario to Denver Intl, which days they fly and book direct flights.

Direct departures

Ontario to Denver Intl

Monday

Air Canada, Frontier, Southwest, +1 more

Air Canada, Frontier, +2 more

Tuesday

Air Canada, Frontier, Southwest, +1 more

Air Canada, Frontier, +2 more

Wednesday

Air Canada, Frontier, Southwest, +1 more

Air Canada, Frontier, +2 more

Thursday

Air Canada, Frontier, Southwest, +1 more

Air Canada, Frontier, +2 more

Friday

Air Canada, Frontier, Southwest, +1 more

Air Canada, Frontier, +2 more

Saturday

Air Canada, Frontier, Southwest, +1 more

Air Canada, Frontier, +2 more

Sunday

Air Canada, Frontier, Southwest, +1 more

Air Canada, Frontier, +2 more

See more direct flights

Direct returns

Denver Intl to Ontario

Monday

Air Canada, Frontier, Southwest, +1 more

Air Canada, Frontier, +2 more

Tuesday

Air Canada, Frontier, Southwest, +1 more

Air Canada, Frontier, +2 more

Wednesday

Air Canada, Frontier, Southwest, +1 more

Air Canada, Frontier, +2 more

Thursday

Air Canada, Frontier, Southwest, +1 more

Air Canada, Frontier, +2 more

Friday

Air Canada, Frontier, Southwest, +1 more

Air Canada, Frontier, +2 more

Saturday

Air Canada, Frontier, Southwest, +1 more

Air Canada, Frontier, +2 more

Sunday

Air Canada, Frontier, Southwest, +1 more

Air Canada, Frontier, +2 more

See more direct flights
See more direct flights

Top airline flying from Ontario to Denver

 
See real verified KAYAK customer reviews for airlines flying from Ontario to Denver. 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 Ontario to Denver? 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.
6.2
FrontierOverall score based on 4099 reviews
6.6Boarding
5.2Food
7.1Crew
5.8Comfort
4.9Entertainment
Airline reviews

Didn't like anything!! Horrible flight. Small seating area and hard seats. Butt was sore after 2 hour flight to Seattle No entertainment or free refreshments No wifi or USB charging receptacles to charge phone entoute like other airliners Luggage rates were 3 times as much as competitors. Difficult to navigate online luggue process to pre pay before flight Overall bad experience WILL NEVER RIDE OR RECOMMEND FRONTIER TO FRIENDS OR FAMILY MEMBERS!!! THIS IS A SHAME!! MOST MESERIBLE FLIGHT OF MY LIFE!! AND I THOUGHT SPIRIT WAS 👎 YOU GOT THEM BEAD HANDS DOWN!!

2.0 MediocreCharles, May 2024DFW - DEN
Read more about Frontier reviews

Didn't like anything!! Horrible flight. Small seating area and hard seats. Butt was sore after 2 hour flight to Seattle No entertainment or free refreshments No wifi or USB charging receptacles to charge phone entoute like other airliners Luggage rates were 3 times as much as competitors. Difficult to navigate online luggue process to pre pay before flight Overall bad experience WILL NEVER RIDE OR RECOMMEND FRONTIER TO FRIENDS OR FAMILY MEMBERS!!! THIS IS A SHAME!! MOST MESERIBLE FLIGHT OF MY LIFE!! AND I THOUGHT SPIRIT WAS 👎 YOU GOT THEM BEAD HANDS DOWN!!

There were 3 leg for the trip and each leg was delayed by 90 minutes or more. The boarding process takes forever with people waiting on the jetway even though most folks do not have carry-on. The whole process is poorly managed.

Not have to pay for every single item to take a flight. Seating and delays sucked.

Terrible. Seats are bad and the baggage policy is inconsistent

Everything was good, and most importantly on time. They have been extremely tardy in some of my flights

They lost my baggage on my connection flight, it’s been 24 hours since I put my claim in and still no update on my bags.

It’s a cheap airline. I wish they had better seats.

The only issues had were outside of Frontier’s control or weren’t expected. It was a two hour flight they completed fast. We landed almost an hour ahead of schedule. The issues with no entertainment or food weren’t issues since there was no expectations. The issue of the loud or crying babies was outside of frontiers control.

Seats are cramped and very uncomfortable. You have to pay for everything and it is too expensive.

Smooth process and flight. My favorite kind. Uneventful and on-time!

Book cheap flights from Ontario to Denver

Cheapest flights to Denver from Ontario found in 2024

Recent one-way flight deals

 
Only flying one-way? Below are some of the best one-way flight deals from Ontario to Denver found on KAYAK in the last 72 hours.
25/5Sat
directFrontier
2h 22mONT-DEN
£72
5/6Wed
1 stopDelta
4h 56mONT-DEN
£78
4/6Tue
1 stopAlaska Airlines
8h 07mONT-DEN
£80
1/6Sat
1 stopDelta
5h 22mONT-DEN
£83
2/6Sun
1 stopDelta
4h 56mONT-DEN
£99
25/5Sat
1 stopFrontier
4h 07mONT-DEN
£104
25/5Sat
1 stopUnited Airlines
5h 01mONT-DEN
£107
23/5Thu
1 stopDelta
4h 56mONT-DEN
£115
11/5Sat
1 stopAlaska Airlines
5h 53mONT-DEN
£123
26/9Thu
2 stopsUnited Airlines
14h 22mONT-DEN
£281

Search by stops

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Last minute flights from Ontario to Denver

Last minute flight, train and bus deals

 
These last-minute flight deals are the cheapest flights found on KAYAK in the last 72 hours for flights from Ontario to Denver that are departing in the next 10 days.
10/5Fri
multi-stopAlaska Airlines
6h 18mONT-DEN
11/5Sat
multi-stopAlaska Airlines
15h 43mDEN-ONT
£410
6/5Mon
multi-stopAlaska Airlines
26h 53mONT-DEN
18/5Sat
multi-stopAlaska Airlines
9h 21mDEN-ONT
£426
8/5Wed
multi-stopAlaska Airlines
15h 53mONT-DEN
14/5Tue
multi-stopAlaska Airlines
6h 43mDEN-ONT
£458
6/5Mon
multi-stopAlaska Airlines
25h 53mONT-DEN
18/5Sat
multi-stopAlaska Airlines
9h 21mDEN-ONT
£490
10/5Fri
multi-stopAlaska Airlines
6h 18mONT-DEN
11/5Sat
multi-stopAlaska Airlines
16h 08mDEN-ONT
£510
8/5Wed
multi-stopUnited Airlines
7h 56mONT-DEN
14/5Tue
multi-stopUnited Airlines
6h 29mDEN-ONT
£571
6/5Mon
multi-stopAlaska Airlines
26h 37mONT-DEN
10/5Fri
multi-stopAlaska Airlines
21h 10mDEN-ONT
£591
6/5Mon
multi-stopAlaska Airlines
16h 56mONT-DEN
10/5Fri
multi-stopAlaska Airlines
17h 01mDEN-ONT
£595
6/5Mon
multi-stopAlaska Airlines
15h 56mONT-DEN
10/5Fri
multi-stopAlaska Airlines
17h 01mDEN-ONT
£599
10/5Fri
multi-stopAlaska Airlines
16h 59mONT-DEN
11/5Sat
multi-stopAlaska Airlines
28h 55mDEN-ONT
£603

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Ontario - Denver Flights

Departure:

Ontario (ONT)United States

Destination:

Denver (DEN)United States

Return flight deals:

Denver - Ontario

Cabin classes:

£497

Browse origins:

  • Flights » 
  • Ontario

Browse destinations:

  • Flights » 
  • Denver