Cheap Flight Tickets from Denver (DEN) to Ontario (ONT), Starting at $74

Good to Know: Cheapest and Fastest DEN - ONT Flights

Useful information for finding best airline tickets from Denver International to Ontario International on your next trip.

Cheapest Round Trip Flight

$256

WN Southwest Airlines • nonstop • 3h 55m

Nov 01 – Nov 04

The cheapest round trip flight from Denver to Ontario (DEN-ONT-DEN) is currently $256

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Cheapest One way Flight

$74

WN Southwest Airlines • 1 stop • 8h 30m

Jan 07

The cheapest one way flight from Denver to Ontario (DEN-ONT) is currently $74

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Cheapest Direct Flight

$256

WN Southwest Airlines • nonstop • 3h 55m

Nov 01

The cheapest nonstop flight from Denver to Ontario (DEN-ONT) is currently $256

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Fastest Flight

3h 45m

The fastest nonstop flight from Denver to Ontario (DEN-ONT) takes 3h 45m

Top Airlines Flying from Denver to Ontario

Southwest Airlines-WN

Southwest Airlines

Delta Airline, DL

Delta Airlines

United Airlines, UA

United Airlines

American Airlines, AA

American Airlines

Alaska Airlines -AS

Alaska Airlines

Latest Flight Deals from Denver (DEN) to Ontario (ONT)

Compare and book low fare round-trip air tickets from Denver to Ontario. Ideal for travelers with confirmed return itineraries.

Nov 01 - Nov 04, Economy
WN
Denver → Ontario
3h 55m
8:30 AM - 10:05 AM • nonstop
WN
Denver → Ontario
3h 40m
12:25 PM - 3:45 PM • nonstop
$256
Southwest Airlines
Nov 01 - Nov 04, Economy
WN
Denver → Ontario
3h 45m
8:20 PM - 9:45 PM • nonstop
WN
Denver → Ontario
3h 40m
5:45 PM - 9:05 PM • nonstop
$256
Southwest Airlines
Nov 01 - Nov 04, Economy
UA
Denver → Ontario
3h 59m
5:50 PM - 7:29 PM • nonstop
UA
Denver → Ontario
3h 46m
2:29 PM - 5:55 PM • nonstop
$278
United Airlines
Mar 31 - Apr 08, Economy
WN
Denver → Ontario
3h 45m
12:50 PM - 2:15 PM • nonstop
WN
Denver → Ontario
3h 35m
7:00 AM - 10:15 AM • nonstop
$284
Southwest Airlines
Mar 31 - Apr 08, Economy
WN
Denver → Ontario
3h 50m
8:40 AM - 10:10 AM • nonstop
WN
Denver → Ontario
3h 35m
7:00 AM - 10:15 AM • nonstop
$294
Southwest Airlines
Nov 01 - Nov 04, Economy
AA
Denver → Ontario
10h 29m
1:13 PM - 6:42 PM • 1 stop
AA
Denver → Ontario
7h 4m
9:50 AM - 3:14 PM • 1 stop
$557
American Airlines

Fly from Denver to Ontario with the Best Airfare Deals on FareLeaders

Looking for a cheap last-minute deal or the best round-trip flight from Denver to Ontario? Find the biggest savings on one-way and round-trip tickets right here.

FAQs on Denver to Ontario Flights

What are the airports in Denver?
DEN
What’s the most popular airline flying from DEN to ONT?
The most popular airline flying from Denver to Ontario are
Can I fly from DEN to ONT non-stop?
Yes, you can fly DEN to ONT non-stop on
Which airlines fly nonstop between Denver and Ontario?
The non-stop flights between Denver and Ontario are .
What’s the earliest departure time from DEN to ONT Airport?
The earliest flight leaves DEN at 5:30 am and lands in ONT - Ontario International
What are the airports in Ontario?
ONT
Can I make changes to my Denver to Ontario flight tickets or cancel them on FareLeaders.com?
No. We are an airfare comparison site. All the tickets are booked by the travel agent offering the flight deal and any changes or cancellations to be made are directly done directly by them or the airlines.
Can I cancel my flight tickets from DEN to ONT?
Read the fare rules of the Denver to Ontario air tickets booked. Some airlines allow you to cancel the tickets within a stipulated time period with a cancellation fee.
Which airline alliances offer flights from Denver and Ontario?
operate flights between Denver and Ontario
How long does a flight from Denver to Ontario take?
It takes approximately 2 hour to fly non-stop from DEN to ONT, which is 818.62 miles by air.
Which airlines provide the cheapest flights from Denver (DEN) to Ontario (ONT) ?
In the past couple of days, the cheapest tickets to ONT from DEN were found on WN : USD 178
Do I need a passport to fly between DEN and ONT?
No
What’s the latest departure time from DEN to ONT ?
The last flight leaves DEN at 1:500 pm

Essential Information for Booking Flights from Denver (DEN) - AI Insights

What's the cheapest airline from den to ont?
Frontier Airlines offers budget-friendly flights from Denver (DEN) to Ontario (ONT) with a one-way trip, suitable for 4 passengers. The flight has 1 stop and can be booked 36 days in advance. You can find affordable airfares with Frontier Airlines, which is known for its low fares and savings.
What's the popular airline to fly from den to ont?
You can fly from Denver International Airport (DEN) to Ontario International Airport (ONT) with Southwest Airlines (WN), which offers budget-friendly flights. This one-way trip has one stop and can be booked in advance. Please check for the latest airfares and cheap flights on fareleaders.com.
What's the cheapest day of the week to fly from den to ont?
The cheapest day to fly from Denver to Ontario is Sunday. Flying on Sundays can result in lower airfare prices compared to other days of the week. Booking in advance, such as 36 days prior to your trip, can also help secure better deals on flights. Low fares and budget-friendly options are available for this route.
What's the cheapest month to fly from den to ont?
The cheapest month to fly from Denver to Ontario is November, as it tends to have lower airfares compared to other months. You can find budget-friendly flights during this time to accommodate your group of four. Look for savings on airfares to make your trip more affordable.
Which airline/airlines fly from den to ont?
The airlines that fly from Denver International Airport (DEN) to Ontario International Airport (ONT) include United Airlines, Delta Airlines, Alaska Airlines, JetBlue Airways, Frontier Airlines, Southwest Airlines, and American Airlines.
What is the cheapest airfare from Denver International Airport (DEN) to Ontario International Airport (ONT) for a one-way trip?
The cheapest airfare from Denver International Airport (DEN) to Ontario International Airport (ONT) for a one-way trip with Frontier Airlines (F9) is available on Sundays in November, with prices starting from $200.
Can I book a flight from Denver to Ontario with a stopover?
Yes, you can book a flight from Denver to Ontario with a stopover on fareleaders.com. Search for flights with United Airlines (UA), Delta Airlines (DL), Alaska Airlines (AS), JetBlue Airways (B6), Frontier Airlines (F9), or Southwest Airlines (WN) and filter by "One Way trip (single leg)" and "Stopover" options.
How many advance booking days do I need to book a one-way economy flight?
You need to book a one-way economy flight at least 36 advance booking days in advance to get the best airfare on fareleaders.com.
What is the best way to find cheap flights on fareleaders.com?
The best way to find cheap flights on fareleaders.com is to use our search engine, filter by "Cheapest Airfare" and "One Way trip (single leg)" options, and consider flying on Sundays in November with airlines like Frontier Airlines (F9) or Southwest Airlines (WN).
Can I search for flights on the website during the month of July?
Yes, you can search for flights on fareleaders.com during the month of July. However, please note that prices may be higher during peak travel seasons.
What is the typical duration of a one-way trip from Denver to Ontario?
The typical duration of a one-way trip from Denver to Ontario is 4 hours and 30 minutes.
How can I ensure I get the best airfare for my travel dates?
To ensure you get the best airfare for your travel dates, use fareleaders.com, filter by "Cheapest Airfare" and "One Way trip (single leg)" options, and consider flying on Sundays in November with airlines like Frontier Airlines (F9) or Southwest Airlines (WN).

Denver (DEN) to Ontario (ONT): Airport Information

Origin Airport Denver International , Denver, US
Destination Airport Ontario International , Ontario, US
Distance 819 miles

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