A daylight view of Ball Arena amidst Denver's urban landscape, highlighting its architectural design. — flights from Ontario to Denver
OntarioDenver

Flights from Ontario to Denver

Nonstop flights from Ontario (ONT) to Denver (DEN) take about 2h 9m (1,316 km). Frontier Airlines flies it. Lowest fare seen: $175 one-way, nonstop (12 Oct 2026).

All flights from Ontario →All flights to Denver →

Book from $175 one-way

Photo of Denver: Noel Aph on Pexels.

When you land in Denver

The airport transfer and the few things worth sorting before you fly.

A daylight view of Ball Arena amidst Denver's urban landscape, highlighting its architectural design. — arriving in Denver

Airport transfer

DEN → Denver, booked before you fly

A private driver meets you in arrivals at a price agreed when you book. Book with Welcome Pickups.

See transfer prices
Silhouette of an airplane landing with a stunning sunset sky in Ontario, California. — lounges at Ontario AirportOntario Airport · 2 lounges
Before you flyAirport lounges at Ontario →
Trains, buses and taxi faresDEN to Denver: getting into town →

Things to book in Denver

All 10 things to do in Denver →
from €51.58
Elitch Gardens 4.4 · 60 Tiqets reviews
from €48.20
Denver Attraction Passes 4.5 · 54 Tiqets reviews
from €26.78
Denver Botanic Gardens 4.5 · 54 Tiqets reviews
Downtown Aquarium (Denver)from €48.20
Downtown Aquarium Denver 4.5 · 54 Tiqets reviews

Find hotels in Denver

Hotels, hostels & more · Expedia

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Airlines flying Ontario to Denver

Carriers on ONT–DEN according to our route data and nonstop fares seen as of 12 Oct 2026. Not a complete list.

✈ Frontier Airlinesnonstop fare seen

More for this trip

Frequently asked questions — Ontario to Denver flights

How long is the flight from Ontario to Denver?
A nonstop flight from Ontario (ONT) to Denver (DEN) takes about 2h 9m, covering 1,316 km. That is an estimate from the distance — actual time varies with the airline, aircraft and winds, and connecting itineraries take longer.
How far is Ontario from Denver by air?
The great-circle distance between Ontario International Airport and Denver International Airport is 1,316 km (818 miles), a medium-haul route.
Which airlines fly from Ontario to Denver?
Airlines with flights or nonstop fares on the ONT–DEN route include Frontier Airlines. This is not a complete list — schedules change by season, so check the current options before booking.
How much does a flight from Ontario to Denver cost?
The lowest one-way fare seen recently on ONT–DEN was $175 USD with Frontier Airlines (nonstop), departing 21 Oct 2026, found in fare searches as of 12 Oct 2026. Fares change constantly and depend on the date, so check the current price before booking.
Do I need a visa to travel from Ontario to Denver?
It depends on your passport. Some nationalities can enter Denver visa-free or get a visa on arrival; others must apply in advance. Use AirConnect's Visa Checker to see the rules for your passport.

Sources: fares from Travelpayouts flight-search data, seen 12 Oct 2026; airlines from each carrier's published network and nonstop fares on sale; distance from OurAirports coordinates; flight time estimated from distance. Fares change daily.

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