S$126 Cheap Flights from Denver to Ontario Intl. Airport

View S$126 flight on Thu, 20 Aug, 2026Opens in a new window

Popular airlines from Denver Intl. Airport (DEN) to Ontario Intl. Airport (ONT)

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Cheap Flights from Denver to Ontario Intl. Airport (DEN-ONT)

Prices were available within the past 7 days and start at S$126 for one-way flights and S$252 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Delta
Thu, 20 Aug - Mon, 24 Aug
DEN
Denver
ONT
Ontario
S$252 Return, found 5 days ago
S$252
Return
found 5 days ago
Select Delta flight, departing Thu, 20 Aug from Denver to Ontario, returning Mon, 24 Aug, priced at S$252 found 5 days ago
Delta
Thu, 20 Aug - Mon, 24 Aug
DEN
Denver
ONT
Ontario
S$291 Return, found 5 days ago
S$291
Return
found 5 days ago
Select Delta flight, departing Thu, 20 Aug from Denver to Ontario, returning Mon, 24 Aug, priced at S$291 found 5 days ago
United
Thu, 20 Aug - Mon, 24 Aug
DEN
Denver
ONT
Ontario
S$304 Return, found 5 days ago
S$304
Return
found 5 days ago
Select United flight, departing Thu, 20 Aug from Denver to Ontario, returning Mon, 24 Aug, priced at S$304 found 5 days ago
United
Thu, 20 Aug - Mon, 24 Aug
DEN
Denver
ONT
Ontario
S$330 Return, found 5 days ago
S$330
Return
found 5 days ago
Select United flight, departing Thu, 20 Aug from Denver to Ontario, returning Mon, 24 Aug, priced at S$330 found 5 days ago
United
Thu, 20 Aug - Mon, 24 Aug
DEN
Denver
ONT
Ontario
S$343 Return, found 5 days ago
S$343
Return
found 5 days ago
Select United flight, departing Thu, 20 Aug from Denver to Ontario, returning Mon, 24 Aug, priced at S$343 found 5 days ago
American Airlines
Thu, 20 Aug - Mon, 24 Aug
DEN
Denver
ONT
Ontario
S$343 Return, found 5 days ago
S$343
Return
found 5 days ago
Select American Airlines flight, departing Thu, 20 Aug from Denver to Ontario, returning Mon, 24 Aug, priced at S$343 found 5 days ago
United
Thu, 20 Aug - Mon, 24 Aug
DEN
Denver
ONT
Ontario
S$356 Return, found 5 days ago
S$356
Return
found 5 days ago
Select United flight, departing Thu, 20 Aug from Denver to Ontario, returning Mon, 24 Aug, priced at S$356 found 5 days ago
United
Thu, 20 Aug - Mon, 24 Aug
DEN
Denver
ONT
Ontario
S$393 Return, found 5 days ago
S$393
Return
found 5 days ago
Select United flight, departing Thu, 20 Aug from Denver to Ontario, returning Mon, 24 Aug, priced at S$393 found 5 days ago
United
Thu, 20 Aug - Mon, 24 Aug
DEN
Denver
ONT
Ontario
S$406 Return, found 5 days ago
S$406
Return
found 5 days ago
Select United flight, departing Thu, 20 Aug from Denver to Ontario, returning Mon, 24 Aug, priced at S$406 found 5 days ago
Delta
Fri, 4 Sept - Mon, 7 Sept
DEN
Denver
ONT
Ontario
S$473 Return, found 5 days ago
S$473
Return
found 5 days ago
Select Delta flight, departing Fri, 4 Sept from Denver to Ontario, returning Mon, 7 Sept, priced at S$473 found 5 days ago

Frequently asked questions

How much is a flight from Denver Intl. Airport (DEN) to Ontario Airport?
Round-trip tickets from DEN to Ontario Airport start from S$252. This price is based on fares quoted within the last 7 days on Expedia for flights departing within the next year — book ASAP to avoid missing out. Prices and availability are subject to change. Additional terms apply.
Do I need to pay a cancellation fee if I cancel my flight from DIA airport to ONT?
Most flights can be cancelled online, but every air carrier has different terms and conditions. If you do decide to cancel your flight, check out our Customer Service Portal and follow the instructions.
How do I find cheap flights from DEN to ONT that have flexible change policies?
Many airlines offer the option to reschedule your flight without a change fee. All you pay is the difference between the original flight and the new flight. When you're searching for Denver Airport to Los Angeles - Ontario Intl. Airport (ONT) flights, you'll see a "no change fees" filter for you to select.
How far is the flight from Denver Airport to ONT?
A flight distance of just 1,300 kilometres separates Denver and Ontario. Once you're up in the skies, you won't get a chance to do much more than read the magazine in your seat pocket.
Which airlines fly direct from DEN to Los Angeles - Ontario Intl. Airport (ONT)?
A popular airline that flies from DEN to Ontario Airport is Southwest Airlines (WN). It offers 99 monthly flights. Operating 60 flights each month along this route, Frontier Airlines (F9) is another top pick.
Are DEN to ONT flight tickets cheaper when they're purchased at the last minute?
Late planners can sometimes find a bargain, with some of the cheapest airfares from Denver Airport to Ontario Airport surfacing a few weeks prior to the departure date. If you'd rather book ahead, Expedia compares and updates the best flight deals regularly — as early as 12 months in advance in some cases. It depends on the carrier though, as not all airlines quote prices that far in advance.

Travel information

Origin airport
Denver Intl.
Destination airport
Ontario Intl. Airport
Return price
S$252
Distance
1306 km
Average flight time
1 hour 19 mins

Book with confidence

Perfect flights from Denver to Ontario Intl. Airport

Your Journey from Denver to Ontario Intl. Airport

Start your unforgettable journey with Expedia. Our broad selection of flights from Denver to Ontario Intl. Airport caters to every travel need. Whether you're yearning for a romantic escape, a solo adventure, or a cultural immersion, we've got you covered.
 

Choosing Your Ideal Flight

With Expedia, you have access to a wide range of airlines, including Delta, United, American Airlines. Our selection of flights from Denver Intl. to Ontario Intl. Airport caters to every traveler's requirements, ensuring your journey aligns with your schedule. With options from 20 airlines, you're bound to find the perfect flight.
 

Maximizing Value with Denver to Ontario Intl. Airport Flights

Experience the joy of finding cheap flights from Denver Intl. to Ontario Intl. Airport that fit your budget. Keep an eye out for our special deals and discounts, and check our flexible one-way fares from S$126 and roundtrip prices from S$252*.
 

Pre-Flight Essentials

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Experience the Vibrant Ontario Intl. Airport

Picture yourself stepping off the plane in Ontario Intl. Airport and immersing yourself in the unique atmosphere of . From local markets to cultural festivals, each city offers its distinct charm. Make the most of your trip by exploring local attractions and indulging in the local cuisine. With Expedia, explore all this and more, tailored to your budget.
 

Added Convenience on Your Denver to Ontario Intl. Airport Flight

Traveling with Expedia is more than just a flight. We offer details about in-flight amenities, baggage policies, and more to ensure a smooth and hassle-free journey. Choose from our variety of airlines and embark on a memorable journey from Denver to Ontario Intl. Airport.
 

Beyond the Flight – Exploring Ontario Intl. Airport

With Expedia, your adventure extends beyond the flight. Explore Ontario Intl. Airport at your own pace by renting a car or booking a hotel. Discover hidden gems off the beaten path and create unforgettable memories.
 

Book Your Flight from Denver to Ontario Intl. Airport with Confidence

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*Note: Prices may vary based on availability and are subject to change.
Perfect flights from Denver to Ontario Intl. Airport

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