Cheap flights from Ontario to Denver

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Travelers usually depart from Ontario International, Ontario Bus Stop, Ontario, CA station, or Montclair (Ontario) when they travel from Ontario to Denver. Book your trip to arrive at Denver International, or Denver Union Station. The distance between Ontario and Denver is 1317 km. The most popular airlines for this route are Frontier Airlines, United Airlines, American Airlines, Delta Air Lines, and Spirit Airlines. Ontario and Denver have 147 direct flights per week.

Weekly direct flights

MondaysTuesdaysWednesdaysThursdaysFridaysSaturdaysSundays
Direct flights3333-33
Fly direct with

Frontier Airlines on Mondays, Tuesdays, Wednesdays, Thursdays, Fridays, Saturdays, and Sundays.

United Airlines on Mondays, Tuesdays, Wednesdays, Thursdays, Fridays, Saturdays, and Sundays.

Check-in for a flight from Ontario to Denver

NameCarrier codeIATA CodePassport needed during bookingOnline check-in available
Frontier AirlinesFFTF9NoOpens 24 days before flight
Closes 1 hours before flight
United AirlinesUALUAYesNo
American AirlinesAALAAYesNo
Delta Air LinesDALDLYesOpens 24 days before flight
Closes 1 hours before flight
Spirit AirlinesNKSNKNoOpens 24 days before flight
Closes 1 hours before flight

Frequently asked questions

How long does it take to travel from Ontario to Denver?
A one-way nonstop (direct) flight between Ontario and Denver takes around 2.3 hours.
What is the flight distance between Ontario and Denver?
The flight distance between Ontario and Denver is 1317 km.
What airlines offer nonstop (direct) flights between Ontario and Denver?
Several carriers operate flights between Ontario and Denver. Airlines offering nonstop (direct) flights include Frontier Airlines, United Airlines.
What are the most popular routes to and from Ontario?
Travelers frequently search for route combinations, such as Ontario and Orlando, Austin, Las Vegas, Atlanta, Sacramento, San Francisco, Seattle, San Antonio, Guadalajara, Charlotte, New Orleans, Fort Lauderdale, Philadelphia, Washington, D.C., Oakland, San Jose, Detroit, Minneapolis, Chicago, Houston.
What are the most popular routes to and from Denver?
Travelers frequently search for route combinations, such as Denver and Chicago, Dallas, Minneapolis, Los Angeles, Washington, D.C., Houston, Orlando, San Francisco, Atlanta, Las Vegas, Austin, Phoenix, Philadelphia, San Diego, Miami, New York, Tampa, Detroit, Seattle, Salt Lake City.
What airports are near Ontario?
The main airport in Ontario is Ontario International. It is also served by Los Angeles International, San Diego International, Ontario International, Tijuana International, John Wayne, Hollywood Burbank, Long Beach, Palm Springs International, Meadows Field, Santa Barbara Municipal.
What airports are near Denver?
The main airport in Denver is Denver International. It is also served by Colorado Springs, Laramie Regional, Eagle County Regional, Cheyenne Regional, Pueblo Memorial.
Is it possible to combine flights, buses, and trains in one itinerary when traveling between Ontario and Denver?
Yes, it's possible to combine different modes of transport between Ontario and Denver thanks to our Virtual Interlining technology. Making use of not only flights but also trains and buses between Ontario and Denver can give rise to new adventures. Read more about how Virtual Interlining works on Kiwi.com Stories.
What is Virtual Interlining and how do I use it?
Virtual Interlining provides a revolutionary way of traveling. You can combine different modes of transport like flights, trains, and buses into one itinerary. And this often saves money. Thanks to the world's largest carrier database, the Kiwi.com search function enables anyone to mix and match different modes of transport easily.
Which airlines fly between Ontario and Denver?
When's the best time to travel between Ontario and Denver?
What flights operate between Ontario and Denver?
How many airports are there near Ontario?
How many airports are there near Denver?
What time do nonstop (direct) flights between Ontario and Denver depart?
What time do nonstop (direct) flights between Ontario and Denver arrive?
What time do flights between Ontario and Denver depart?
What time do flights between Ontario and Denver arrive?

Planning a trip? Thanks to our Virtual Interlining algorithm, we offer billions of route combinations between any A and any B in the world by plane, train, and bus. Find the cheapest routes and best deals for you, as well as the best dates on which to travel.

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