Cheap flights from Denver, CO to Ontario, CA

Flights starting at $44. Choose between Frontier Airlines, United Airlines, or Alaska Airlines to find the best price.

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Book your trip to arrive at Ontario International, or Montclair (Ontario). The distance between Denver and Ontario is 1317 km. The most popular airlines for this route are Frontier Airlines, United Airlines, Alaska Airlines, and Spirit Airlines. Denver and Ontario have 103 direct flights per week.

Weekly direct flights

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

Weekly direct flights for Sun 18.02 - Sat 24.02

AirlineSun 18.02Mon 19.02Tue 20.02Wed 21.02Thu 22.02Fri 23.02Sat 24.02
3322222
2222222

Weekly direct flights for Sun 25.02 - Sat 02.03

AirlineSun 25.02Mon 26.02Tue 27.02Wed 28.02Thu 29.02Fri 01.03Sat 02.03
4222222
2222222

Weekly direct flights for Sun 03.03 - Sat 09.03

AirlineSun 03.03Mon 04.03Tue 05.03Wed 06.03Thu 07.03Fri 08.03Sat 09.03
2222222
2221222

Weekly direct flights for Sun 10.03 - Sat 16.03

AirlineSun 10.03Mon 11.03Tue 12.03Wed 13.03Thu 14.03Fri 15.03Sat 16.03
2222222
2222222

Check-in for a flight from Denver to Ontario

NameCarrier codeIATA CodePassport needed during bookingOnline check-in available
Frontier AirlinesFFTF9NoOpens 24 days before flight
Closes 1 hours before flight
United AirlinesUALUAYesNo
Alaska AirlinesASAASNoOpens 24 days before flight
Closes 1 hours before flight
Spirit AirlinesNKSNKNoOpens 24 days before flight
Closes 1 hours before flight

Weather in Ontario

Average Weather

MonthAverage monthly max temperatureAverage monthly min temperature
January18°C7°C
February18°C7°C
March20°C8°C
April23°C10°C
May25°C13°C
June29°C16°C
July33°C19°C
August33°C20°C
September32°C18°C
October27°C15°C
November22°C10°C
December17°C7°C
Hottest Month
33°C
August
Coldest month
7°C
February
Sunny days
339
days per year

14 day forecast

Sunday
18 Feb
17°C9°C
25 Feb
20°C12°C
Monday
19 Feb
91%
13°C12°C
26 Feb
79%
13°C10°C
Tuesday
20 Feb
85%
13°C11°C
27 Feb
87%
13°C6°C
Wednesday
21 Feb
80%
15°C9°C
28 Feb
15°C6°C
Thursday
22 Feb
18°C8°C
29 Feb
17°C8°C
Friday
23 Feb
21°C9°C
1 Mar
20°C9°C
Saturday
24 Feb
21°C13°C
2 Mar
23°C12°C

Frequently asked questions

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

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