Cheap flights from Ontario, CA to Denver, CO

Flights starting at $43. Choose between Frontier Airlines, American Airlines, or United Airlines to find the best price.

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Tips to know when travelling to Denver

Travelers usually depart from Ontario International, Montclair (Ontario), Ontario Bus Stop, or Ontario, CA station 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, American Airlines, United Airlines, Alaska Airlines, and Spirit Airlines. Ontario and Denver have 153 direct flights per week.

Weekly direct flights

Discover the top airlines offering direct flights from Ontario to Denver in the next month. You’ll find the number of daily direct flights per airline in the table.

Weekly direct flights for Sun 19.11 - Sat 25.11

AirlineSun 19.11Mon 20.11Tue 21.11Wed 22.11Thu 23.11Fri 24.11Sat 25.11
2222122
2222222

Weekly direct flights for Sun 26.11 - Sat 02.12

AirlineSun 26.11Mon 27.11Tue 28.11Wed 29.11Thu 30.11Fri 01.12Sat 02.12
2224232
2222222

Weekly direct flights for Sun 03.12 - Sat 09.12

AirlineSun 03.12Mon 04.12Tue 05.12Wed 06.12Thu 07.12Fri 08.12Sat 09.12
2222222
2222222

Weekly direct flights for Sun 10.12 - Sat 16.12

AirlineSun 10.12Mon 11.12Tue 12.12Wed 13.12Thu 14.12Fri 15.12Sat 16.12
2222222
2222222

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
American AirlinesAALAANoNo
United AirlinesUALUAYesNo
Alaska AirlinesASAASNoOpens 24 days before flight
Closes 1 hours before flight
Spirit AirlinesNKSNKNoOpens 24 days before flight
Closes 1 hours before flight
Learn more about COVID-19 restrictions in United States in our dedicated Stories article.

Frequently asked questions

How long does it take to travel from Ontario to Denver?
What is the flight distance between Ontario and Denver?
What airlines offer nonstop (direct) flights between Ontario and Denver?
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What airports are near Ontario?
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Is it possible to combine flights, buses, and trains in one itinerary when traveling between Ontario and Denver?
What is Virtual Interlining and how do I use it?
Which airlines fly between Ontario and Denver?
When's the best time to travel between Ontario and Denver?
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What time do nonstop (direct) flights between Ontario and Denver depart?
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What time do flights between Ontario and Denver depart?
What time do flights between Ontario and Denver arrive?

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