Cheap Flight Tickets from Denver (DEN) to Ontario (ONT), Starting at $137

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

$305

F9 Frontier Airlines • 1 stop • 13h 56m

Sep 09 – Sep 14

The cheapest round trip flight from Denver to Ontario (DEN-ONT-DEN) is currently $305

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Cheapest One way Flight

$194

WN Southwest Airlines • 1 stop • 10h 20m

Sep 29

The cheapest one way flight from Denver to Ontario (DEN-ONT) is currently $194

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Cheapest Direct Flight

$137

F9 Frontier Airlines • nonstop • 3h 41m

Sep 08

The cheapest nonstop flight from Denver to Ontario (DEN-ONT) is currently $137

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Fastest Flight

3h 35m

The fastest nonstop flight from Denver to Ontario (DEN-ONT) takes 3h 35m

Top Airlines Flying from Denver to Ontario

Alaska Airlines -AS

Alaska Airlines

Southwest Airlines-WN

Southwest Airlines

Delta Airline, DL

Delta Airlines

American Airlines, AA

American Airlines

United Airlines, UA

United 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.

Sep 09 - Sep 14, Economy
F9
Denver → Ontario
13h 56m
10:40 AM - 6:16 PM • 1 stop
F9
Denver → Ontario
3h 42m
11:45 AM - 3:07 PM • nonstop
$305
Frontier Airlines
Sep 08 - Sep 15, Economy
UA
Denver → Ontario
8h 47m
7:45 AM - 12:12 PM • 1 stop
UA
Denver → Ontario
3h 41m
5:00 AM - 8:21 AM • nonstop
$313
United Airlines
Sep 04 - Sep 13, Economy
AS
Denver → Ontario
10h 50m
5:34 PM - 11:24 PM • 1 stop
AS
Denver → Ontario
10h 31m
2:15 PM - 9:46 PM • 1 stop
$376
Alaska Airlines
Sep 04 - Sep 13, Economy
AS
Denver → Ontario
10h 47m
8:22 AM - 2:09 PM • 1 stop
AS
Denver → Ontario
10h 31m
2:15 PM - 9:46 PM • 1 stop
$376
Alaska Airlines
Sep 04 - Sep 13, Economy
AS
Denver → Ontario
10h 5m
12:05 PM - 5:10 PM • 1 stop
AS
Denver → Ontario
10h 31m
2:15 PM - 9:46 PM • 1 stop
$384
Alaska Airlines
Sep 04 - Sep 13, Economy
AS
Denver → Ontario
10h 5m
12:05 PM - 5:10 PM • 1 stop
AS
Denver → Ontario
3h 50m
2:05 PM - 5:35 PM • nonstop
$407
Alaska 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 7:45 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 194
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 10:29 pm

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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