Southwest® flights from Ontario/LA to Denver from $89

Promo Code

Low fares from Ontario/LA to Denver

$

Ontario/LA (ONT)to

Denver (DEN)
Depart: 04/08/2026

One-way

Basic

From
$89
Seen: 17 hrs ago

Ontario/LA (ONT)to

Denver (DEN)
Depart: 04/28/2026

One-way

Basic

From
$89
Seen: 13 hrs ago

Ontario/LA (ONT)to

Denver (DEN)
Depart: 06/09/2026

One-way

Basic

From
$89
Seen: 13 hrs ago

Ontario/LA (ONT)to

Denver (DEN)
Depart: 05/05/2026

One-way

Basic

From
$89
Seen: 12 hrs ago

Ontario/LA (ONT)to

Denver (DEN)
Depart: 05/06/2026

One-way

Basic

From
$89
Seen: 7 hrs ago

Ontario/LA (ONT)to

Denver (DEN)
Depart: 05/26/2026

One-way

Basic

From
$89
Seen: 15 hrs ago

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Explore flights from Ontario/LA to Denver

Mar 2026
From$199*
Seen: 9 hrs ago
One Way/Basic
Apr 2026
From$89*
Seen: 13 hrs ago
One Way/Basic
May 2026
From$89*
Seen: 15 hrs ago
One Way/Basic
$89
$579
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    • Range$89-$579

    *Fares displayed have been collected within the last 24 hours and may no longer be available at time of booking. Additional fees and charges for optional products and services may apply. Modifying this information may result in a different fare. To find the most updated fare, please visit Southwest.com. Fares listed are Basic, which are subject to additional terms and conditions.

    Flight Details

    Departing from:
    LA/Ontario International Airport
    Arriving at:
    Denver International Airport
    Average flight time:
    2 hours 12 minutes
    Distance:
    819 miles

    Route Information

    156† Weekly flights
    • 3‡ Nonstop flights per day Monday through Friday
    • 3‡ Nonstop flights on Saturday
    • 4‡ Nonstop flights on Sunday

    † Weekly flights based on DOT published scheduled average flights Monday through Sunday between 9/1/2025 and 9/30/2025. Note: route may not operate every day of the week.

    ‡ Nonstop flights based on DOT published scheduled average flights Monday through Sunday between 9/1/2025 and 9/30/2025.

    Questions we hear the most

    The average flight time from Ontario/LA to Denver is 2 hours 12 minutes.
    There are 156 weekly flights from Ontario/LA to Denver on Southwest Airlines.
    Yes, Southwest flies nonstop from Ontario/LA to Denver 3 times per day from Monday through Friday.
    Yes, Southwest flies nonstop from Ontario/LA to Denver 3 times per day on Saturdays and 4 times per day on Sundays.
    To find the lowest fares by day and time to fly Ontario/LA to Denver with Southwest, check out our Low Fare Calendar.
    You can rent a car at Denver International Airport book yours with your flight.
    Yes! Flights from Ontario/LA to Denver—or from here or there to anywhere—can be changed with no change fees. Fare difference may apply.
    Check the status of your upcoming Southwest flight.
    Check out the Southwest Airlines® Help Center for answers about everything Southwest.

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