CA $124 Cheap Flights from Ontario (ONT) to Denver (DEN)

View CA $124 flight on Fri, May 8, 2026Opens in a new window

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

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Cheap flights from Ontario (ONT) to Denver (DEN)

Prices were available within the past 7 days and start at CA $124 for one-way flights and CA $249 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Delta
Tue, May 5 - Tue, May 12
ONT
Ontario
DEN
Denver
CA $249 Roundtrip, found 4 days ago
CA $249
Roundtrip
found 4 days ago
Select Delta flight, departing Tue, May 5 from Ontario to Denver, returning Tue, May 12, priced at CA $249 found 4 days ago
Delta
Tue, May 5 - Tue, May 12
ONT
Ontario
DEN
Denver
CA $273 Roundtrip, found 4 days ago
CA $273
Roundtrip
found 4 days ago
Select Delta flight, departing Tue, May 5 from Ontario to Denver, returning Tue, May 12, priced at CA $273 found 4 days ago
Delta
Fri, May 8 - Mon, May 11
ONT
Ontario
DEN
Denver
CA $274 Roundtrip, found 3 days ago
CA $274
Roundtrip
found 3 days ago
Select Delta flight, departing Fri, May 8 from Ontario to Denver, returning Mon, May 11, priced at CA $274 found 3 days ago
Delta
Tue, May 5 - Tue, May 12
ONT
Ontario
DEN
Denver
CA $285 Roundtrip, found 4 days ago
CA $285
Roundtrip
found 4 days ago
Select Delta flight, departing Tue, May 5 from Ontario to Denver, returning Tue, May 12, priced at CA $285 found 4 days ago
Delta
Tue, May 5 - Tue, May 12
ONT
Ontario
DEN
Denver
CA $298 Roundtrip, found 4 days ago
CA $298
Roundtrip
found 4 days ago
Select Delta flight, departing Tue, May 5 from Ontario to Denver, returning Tue, May 12, priced at CA $298 found 4 days ago
American Airlines
Tue, May 5 - Tue, May 12
ONT
Ontario
DEN
Denver
CA $303 Roundtrip, found 4 days ago
CA $303
Roundtrip
found 4 days ago
Select American Airlines flight, departing Tue, May 5 from Ontario to Denver, returning Tue, May 12, priced at CA $303 found 4 days ago
Delta
Tue, May 5 - Tue, May 12
ONT
Ontario
DEN
Denver
CA $305 Roundtrip, found 4 days ago
CA $305
Roundtrip
found 4 days ago
Select Delta flight, departing Tue, May 5 from Ontario to Denver, returning Tue, May 12, priced at CA $305 found 4 days ago
Delta
Tue, May 5 - Tue, May 12
ONT
Ontario
DEN
Denver
CA $308 Roundtrip, found 4 days ago
CA $308
Roundtrip
found 4 days ago
Select Delta flight, departing Tue, May 5 from Ontario to Denver, returning Tue, May 12, priced at CA $308 found 4 days ago
Alaska Airlines
Tue, May 5 - Tue, May 12
ONT
Ontario
DEN
Denver
CA $360 Roundtrip, found 4 days ago
CA $360
Roundtrip
found 4 days ago
Select Alaska Airlines flight, departing Tue, May 5 from Ontario to Denver, returning Tue, May 12, priced at CA $360 found 4 days ago
United
Fri, May 8 - Mon, May 11
ONT
Ontario
DEN
Denver
CA $375 Roundtrip, found 3 days ago
CA $375
Roundtrip
found 3 days ago
Select United flight, departing Fri, May 8 from Ontario to Denver, returning Mon, May 11, priced at CA $375 found 3 days ago

Frequently asked questions

How much is a flight from Los Angeles - Ontario Intl. Airport (ONT) to DEN?
Start packing your bags, because round-trip flights from Los Angeles - Ontario Intl. Airport (ONT) to DIA airport start from CA $249. That's based on fares advertised within the last 7 days on Expedia for flights departing within the next year. Prices can go up quickly, so book today to secure the best deal. Prices and availability are subject to change. Additional terms apply.
Do I need to pay a cancellation fee if I cancel my flight from ONT to DIA airport?
The majority of flights can be cancelled online, but every airline has a different set of 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 Ontario Airport to Denver Intl. Airport (DEN) that have flexible change policies?
Many carriers will allow you to reschedule your flight without charging a fee. All you pay is the cost difference between the two flights. When searching for Los Angeles - Ontario Intl. Airport (ONT) to DIA airport flights, you'll see a "No change fees" box for you to select.
How many hours is the flight from Ontario Airport to Denver Intl. Airport (DEN)?
The flight from Ontario Airport to DEN usually takes only 2 hours and 16 minutes, so don't get too cozy. There's a good chance the next time you look out the window you'll be descending into Denver.
How far is the flight from ONT to Denver Intl. Airport (DEN)?
The flight distance from Ontario Airport (ONT) to Denver Intl. Airport (DEN) (DEN) is just 1,300 kilometres. You'll be disembarking the plane and collecting your suitcase from the carousel in next to no time.
Which airlines fly direct from Ontario Airport to DEN?
There are several airlines that travel directly from Los Angeles - Ontario Intl. Airport (ONT) to DIA airport. Southwest Airlines (WN) is a great choice, offering 100 flights on this route each month. Love some more options? Check out the airfares with United Airlines (UA). This carrier offers 60 monthly flights between these destinations.
Are ONT to DEN flight tickets cheaper when they're purchased at the last minute?
Booking your trip from Los Angeles - Ontario Intl. Airport (ONT) to Denver Airport at the last minute could save you some cash. However, it could end up costing a good deal more! If you'd rather avoid the risk, book well ahead of your departure date. In fact, Expedia has some of the biggest bargains up to a year in advance. If your preferred air carrier hasn't released tickets yet, check back regularly as deals are updated on Expedia all the time.

Travel information

Origin airport
Los Angeles - Ontario Intl.
Destination airport
Denver Intl.
Roundtrip price
CA $248
Distance
1306 km
Average flight time
3 hours 27 mins

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