€181 Cheap Flights Ontario to Denver (ONT-DEN)

View €181 flight on Wed, 26 Nov 2025Opens in a new window

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

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Cheap flights from Ontario to Denver (ONT-DEN)

Prices were available within the past 7 days and start at €181 for one-way flights and €382 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Delta
Wed, 26 Nov - Sun, 30 Nov
ONT
Ontario
DEN
Denver
€382 Return, found 2 days ago
€382
Return
found 2 days ago
Select Delta flight, departing Wed, 26 Nov from Ontario to Denver, returning Sun, 30 Nov, priced at €382 found 2 days ago
Delta
Wed, 26 Nov - Sun, 30 Nov
ONT
Ontario
DEN
Denver
€390 Return, found 2 days ago
€390
Return
found 2 days ago
Select Delta flight, departing Wed, 26 Nov from Ontario to Denver, returning Sun, 30 Nov, priced at €390 found 2 days ago
American Airlines
Wed, 26 Nov - Sun, 30 Nov
ONT
Ontario
DEN
Denver
€397 Return, found 2 days ago
€397
Return
found 2 days ago
Select American Airlines flight, departing Wed, 26 Nov from Ontario to Denver, returning Sun, 30 Nov, priced at €397 found 2 days ago
United
Wed, 26 Nov - Sun, 30 Nov
ONT
Ontario
DEN
Denver
€400 Return, found 2 days ago
€400
Return
found 2 days ago
Select United flight, departing Wed, 26 Nov from Ontario to Denver, returning Sun, 30 Nov, priced at €400 found 2 days ago
United
Wed, 26 Nov - Sun, 30 Nov
ONT
Ontario
DEN
Denver
€408 Return, found 2 days ago
€408
Return
found 2 days ago
Select United flight, departing Wed, 26 Nov from Ontario to Denver, returning Sun, 30 Nov, priced at €408 found 2 days ago
American Airlines
Wed, 26 Nov - Sun, 30 Nov
ONT
Ontario
DEN
Denver
€416 Return, found 2 days ago
€416
Return
found 2 days ago
Select American Airlines flight, departing Wed, 26 Nov from Ontario to Denver, returning Sun, 30 Nov, priced at €416 found 2 days ago
American Airlines
Wed, 26 Nov - Sun, 30 Nov
ONT
Ontario
DEN
Denver
€482 Return, found 2 days ago
€482
Return
found 2 days ago
Select American Airlines flight, departing Wed, 26 Nov from Ontario to Denver, returning Sun, 30 Nov, priced at €482 found 2 days ago
American Airlines
Wed, 26 Nov - Sun, 30 Nov
ONT
Ontario
DEN
Denver
€493 Return, found 2 days ago
€493
Return
found 2 days ago
Select American Airlines flight, departing Wed, 26 Nov from Ontario to Denver, returning Sun, 30 Nov, priced at €493 found 2 days ago

Find the cheapest month to fly from Ontario (ONT) to Denver (DEN)

April is typically the cheapest month to fly

From €41 - €344 per traveller.

Graph displaying average flight prices per month

Ontario to Denver route information
Origin airport
Los Angeles - Ontario Intl.
Destination airport
Denver Intl.
Return price
€381
Distance
1306 km
Average flight time
3 hours 59 mins

Perfect flights from Ontario to Denver

Embark on an unforgettable journey without breaking the bank with Expedia's incredible deals on cheap flights from Ontario to Denver. Whether you're aching for a romantic escape with your partner, craving an adventurous solo expedition, or yearning to immerse yourself in the local history and culture, we've got you covered.
 
Picture yourself strolling through the streets of , surrounded by breathtaking architecture and absorbing the vibrant atmosphere of this captivating city. Indulge in the mouth-watering local specialties, from tantalizing street food to exquisite fine dining. With Expedia, you can experience all of this and more, without sacrificing your budget.
 
Our flexible Los Angeles - Ontario Intl. to Denver Intl. ticket options cater to your travel preferences, with incredible one-way fares from €181 and roundtrip prices from €382. Whether you're planning a short city break or a longer adventure, our dynamic pricing ensures that you find the best deals for your journey.
 
But the magic doesn't stop there. Expedia offers a range of partner services to enhance your trip. Rent a car at Denver Intl. and explore and its surrounding areas at your own pace. Discover hidden gems off the beaten path, and create unforgettable memories. We also provide a handpicked selection of accommodations, from charming bed and breakfasts to luxury hotels, ensuring that you have a comfortable and memorable stay.
 
Planning your next great adventure is a breeze with Expedia. Our user-friendly platform, unbeatable prices, and round-the-clock customer support are designed to make your travel experience seamless and stress-free. So, why wait? Book your to travel arrangements today and embark on the journey of a lifetime in Denver.

Frequently asked questions

How much is a flight from Los Angeles - Ontario Intl. Airport (ONT) to DIA airport?
Within the past 7 days on Expedia, for flights departing within the next year, the lowest price listed for a round-trip journey from ONT to DIA airport was €382. Cheap tickets don't hang around forever, so make sure you book yours today. Prices and availability are subject to change. Additional terms apply.
Do I need to pay a cancellation fee if I cancel my flight from Ontario Airport to Denver Intl. Airport (DEN)?
Every air carrier has its own set of terms and conditions. If you do decide to cancel, follow the simple instructions on our Customer Service Portal.
How do I find cheap flights from Ontario Airport to DIA airport 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 ONT to Denver Airport flights, you'll see a "no change fees" filter for you to select.
How far is the flight from Los Angeles - Ontario Intl. Airport (ONT) to Denver Intl. Airport (DEN)?
Forget about a movie marathon on this flight — it's just 1,300 kilometres from Ontario to Denver. Find your seat, enjoy the in-flight service and you'll be touching down in no time.
Which airlines fly direct from Ontario Airport to DEN?
There are a few airlines that travel directly from Los Angeles - Ontario Intl. Airport (ONT) to Denver Intl. Airport (DEN). Southwest Airlines (WN) is a top choice, offering 117 flights on this route each month. Frontier Airlines (F9) is another popular choice. It operates 60 flights per month. Between these two airlines, you'll be able to find a great deal from Ontario to Denver.
Are Los Angeles - Ontario Intl. Airport (ONT) to DEN flight tickets cheaper when they're purchased at the last minute?
Flight prices go up and down like a yo-yo, so not always. While last-minute flight deals between Los Angeles - Ontario Intl. Airport (ONT) and Denver Intl. Airport (DEN) are of course possible, it also makes sense to keep an eye on prices well before you fly. In fact, some airlines publish their prices up to a year before the departure date. Expedia is continuously updating the biggest airfare bargains around, so keep checking and be ready to pounce when the price dips.

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