Cheap flights from Denver to Ontario from $38
This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from Denver to Ontario departing on 6/3. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.
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How to get the cheapest flight ticket from Denver to Ontario
Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip
What is the cheapest month to fly to Ontario?
In general, April is the cheapest month to fly from Denver to Ontario. Due to it being the ‘off-season’ during this time, you can expect flight prices to be around $104. If you aren’t able to travel during the month of April, then book flights to Ontario from Denver during August instead. Flights to Ontario in August, while not as cheap as those in April, still average around $112.
What is the cheapest day to depart on your flight to Ontario?
The cheapest day to depart on your flight to Ontario is on a Tuesday when prices can be found for as low as $114. This is often the case because there is less demand to fly during this day of the week. When flying out on a Sunday, the most expensive travel day of the week, you can expect to see flight prices from Denver to Ontario for around $146.
What is the cheapest time of day to depart on your flight to Ontario?
In the morning is the cheapest time of day to fly from Denver to Ontario when you can find flight prices for as low as $120. Flying to Ontario in the morning is an ideal time because this is during off-peak travel hours. If you have a flexible travel schedule, then try to avoid flying at noon when prices are $198 on average. Flights to Ontario from Denver at noon are generally more expensive because this time of day is more convenient for travelers’ schedules.
What is the cheapest Denver Intl to Ontario flight route?
Fly from Denver Intl to Ontario for the best Denver Intl - Ontario flight prices
How far in advance should I book a flight to Ontario?
You are more likely to see cheaper flights to Ontario from Denver when booking 8 weeks ahead of your departure date. In general, you can expect to find flights to Ontario for around $138 when searching 8 weeks out.However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Ontario from Denver for as low as $95 on momondo.
What cabin class options are available on Denver Intl to Ontario flights?
There are 4 cabin classes available to choose from on Denver Intl to Ontario flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.
What is the cheapest airline that flies from Denver Intl to Ontario?
Frontier, Alaska Airlines, and Southwest are the most popular carriers operating from Denver Intl to Ontario
What airlines fly to Ontario?
Frontier, United Airlines and Delta are the top three most popular airlines that fly to Ontario from Denver according to our data. Frontier is the first choice among our users, with 56% of people opting to fly with this airline when traveling to Ontario. Keep in mind that there are 7 different airlines that fly to Ontario on a routine basis, so you have a few additional options to choose from.
How many flights depart from Denver to Ontario on average per day?
As of March 2025, 5 flights take off from Denver and land in Ontario each day. The most common flight departure time for this route is 7:00PM, with 47% of daily flights taking off in the evening.
How many flights depart from Denver to Ontario on average per week?
As of March 2025, 35 flights take off from Denver and land in Ontario each week. The most common flight departure day for this route is Mon, with 31% of weekly flights taking off on this day.
When to book flights from Denver to Ontario
Cheap Denver to Ontario (DEN to ONT) flight deals and tips
Find info about flight duration, direct flights, and airports for your flight from Denver to Ontario
How far is Denver Intl to Ontario by plane?
Denver Intl and Ontario are 800.5 mi apart from one another. In terms of flight time, this usually takes a little over 2h 20m.
When did momondo last update prices for flights from Denver Intl Airport to Ontario Airport?
Prices for flights from Denver Intl Airport to Ontario Airport refresh daily.
How many operators does momondo search for flights from Denver Intl Airport to Ontario Airport?
As of March 2025, there are 3 operators available to choose from for flights from Denver Intl Airport to Ontario Airport.
How old do you have to be to fly from Denver Intl Airport to Ontario Airport?
The minimum age a child must be to fly alone is five but airlines that offer an unaccompanied minor (UNMR) service will have their own age restrictions, including rules around flight length, timings, and stopovers. We always recommend checking with the individual airline you are booking with to travel from Denver Intl Airport to Ontario Airport.
What documentation or ID do you need to fly to Ontario Airport?
The required travel and health documents for your Ontario Airport trip may vary depending on your itinerary and personal circumstances. As a general rule, you should carry multiple documents, including a national ID card or driver's license and a passport valid for six months after your intended arrival at Ontario Airport. We recommend that you seek guidance from your airline or a reliable third party such as IATA.
What is the most popular plane model from Denver to Ontario?
Based on momondo bookings for this flight route, the most popular plane model on flight routes from Denver to Ontario is Airbus A320neo (16.42% of total bookings). The next most popular plane models are Airbus A321neo (13.57%), Boeing 737-800 (11.54%), and Boeing 737-700 Passenger/BBJ1 (winglets) (9.96%).
What is the most popular airline from Denver to Ontario?
Based on momondo bookings for this flight route, the most popular airline on flight routes from Denver to Ontario is Frontier (85% of total bookings). The next most popular airlines are United Airlines (11%) and Southwest (4%).
Best airlines flying from Denver to Ontario
Compare and see reviews for airlines that fly from Denver to Ontario with momondo
| Airline | Rating | Free Cancellation | Price | ||
|---|---|---|---|---|---|
| PriceFrom $46 | Free Cancellation | Rating 6.0 3,318 reviews | |||
| PriceFrom $141 | Free Cancellation | Rating 7.4 8,689 reviews | |||
| PriceFrom $178 | Free Cancellation | Rating 8.1 4,333 reviews |
Southwest Flights From Denver to Ontario
The lowest priced Southwest flight from Denver to Ontario from the last 72 hours was $178. Generally, Southwest has 5 flights on this route every week with an average price of $252. Southwest is rated 8.1/10 by our users.
United Airlines Flights From Denver to Ontario
Another popular option for Denver to Ontario flights is United Airlines (7.4/10, 8,679 ratings). United Airlines flies from Denver to Ontario around 12 times per week, with deals starting from $141 round-trip and rising to an average price of around $312.
Why use momondo?
Why should I use momondo to find a flight deal from Denver to Ontario?
To find the flight that best suits your needs, momondo gathers a range of flights from a large pool of different airlines and agents; you can then use our insights and filters to find and book the right flight to Ontario from Denver.
Can I find flights from Denver to Ontario with flexible booking policies on momondo?
Yes. momondo enables you to select and highlight flights to Ontario from Denver with this policy.
How can momondo help me find flights from Denver to Ontario?
Once all potential Denver to Ontario flight options are in front of you, momondo lets you sort and filter flights based on preferences such as airline, price and flight times amongst many other options.
I’m not ready to book a flight from Denver to Ontario right now. Can momondo alert me if prices change?
Yes momondo offers price alerts on flights to Ontario from Denver. After performing a search on this page you should be able to see the price alert set up feature. Simply provide a valid email address and momondo will instantly alert you when prices change.