Southwest® flights from Portland, ME to Ontario/LA from $194

Promo Code

Low fares from Portland, ME to Ontario/LA

$

Portland, ME (PWM)to

Ontario/LA (ONT)
Depart: 04/30/2026

One-way

Basic

From
$194
Seen: 45 minutes ago

Portland, ME (PWM)to

Ontario/LA (ONT)
Depart: 04/07/2026

One-way

Basic

From
$204
Seen: 1 hour ago

Portland, ME (PWM)to

Ontario/LA (ONT)
Depart: 05/30/2026

One-way

Basic

From
$225
Seen: 2 minutes ago

Portland, ME (PWM)to

Ontario/LA (ONT)
Depart: 04/08/2026

One-way

Basic

From
$234
Seen: 1 hour ago

Portland, ME (PWM)to

Ontario/LA (ONT)
Depart: 04/30/2026

One-way

Choice

From
$234
Seen: 45 minutes ago

Portland, ME (PWM)to

Ontario/LA (ONT)
Depart: 04/07/2026

One-way

Choice

From
$244
Seen: 1 hour ago

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Explore flights from Portland, ME to Ontario/LA

Try alternate month or interact with individual days below in order to find offers.
Mar 2026
No result for this month.
Apr 2026
From$194*
Seen: 45 minutes ago
One Way/Basic
May 2026
From$225*
Seen: 2 minutes ago
One Way/Basic
$204
Displaying fares for March-2026
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    • Range$204-$244

    *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:
    Portland International Jetport
    Arriving at:
    LA/Ontario International Airport
    Distance:
    2598 miles

    Route Information

    45† Weekly flights

    † 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

    There are 45 weekly flights from Portland, ME to Ontario/LA on Southwest Airlines.
    To find the lowest fares by day and time to fly Portland, ME to Ontario/LA with Southwest, check out our Low Fare Calendar.
    You can rent a car at LA/Ontario International Airport book yours with your flight.
    Yes! Flights from Portland, ME to Ontario/LA—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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