Southwest® flights from Portland, OR to Ontario/LA from $135

Promo Code

Low fares from Portland, OR to Ontario/LA

$

Portland, OR (PDX)to

Ontario/LA (ONT)
Depart: 09/21/2026

One-way

Basic

From
$135
Seen: 11 hrs ago

Portland, OR (PDX)to

Ontario/LA (ONT)
Depart: 09/18/2026

One-way

Basic

From
$135
Seen: 4 hrs ago

Portland, OR (PDX)to

Ontario/LA (ONT)
Depart: 08/28/2026

One-way

Basic

From
$135
Seen: 10 minutes ago

Portland, OR (PDX)to

Ontario/LA (ONT)
Depart: 09/08/2026

One-way

Basic

From
$135
Seen: 19 hrs ago

Portland, OR (PDX)to

Ontario/LA (ONT)
Depart: 08/29/2026

One-way

Basic

From
$135
Seen: 19 hrs ago

Portland, OR (PDX)to

Ontario/LA (ONT)
Depart: 08/31/2026

One-way

Basic

From
$135
Seen: 13 hrs ago

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Explore flights from Portland, OR to Ontario/LA

Aug 2026
From$135*
Seen: 10 minutes ago
One Way/Basic
Sep 2026
From$135*
Seen: 19 hrs ago
One Way/Basic
Oct 2026
From$135*
Seen: 2 hrs ago
One Way/Basic
cmp-daily-histogram-bars-legend-min-price-aria-label $135
cmp-daily-histogram-bars-legend-max-price-aria-label $225
Displaying fares for August-2026
  • PDX–ONT, 08/04/2026: From $225
    04

    Tue

    AUG

  • PDX–ONT, 08/05/2026: From $225
    05

    Wed

  • PDX–ONT, 08/06/2026: From $225
    06

    Thu

  • PDX–ONT, 08/07/2026: From $225
    07

    Fri

  • PDX–ONT, 08/08/2026: From $225
    08

    Sat

  • PDX–ONT, 08/09/2026: From $225
    09

    Sun

  • PDX–ONT, 08/10/2026: From $195
    10

    Mon

  • PDX–ONT, 08/11/2026: From $169
    11

    Tue

  • PDX–ONT: cmp-view-offers-disclaimer. Find Offers
    12

    Wed

  • PDX–ONT, 08/13/2026: From $169
    13

    Thu

  • PDX–ONT, 08/14/2026: From $169
    14

    Fri

  • PDX–ONT, 08/15/2026: From $169
    15

    Sat

  • PDX–ONT, 08/16/2026: From $160
    16

    Sun

  • PDX–ONT, 08/17/2026: From $139
    17

    Mon

  • PDX–ONT, 08/18/2026: From $139
    18

    Tue

  • PDX–ONT: cmp-view-offers-disclaimer. Find Offers
    19

    Wed

  • PDX–ONT, 08/20/2026: From $139
    20

    Thu

  • PDX–ONT, 08/21/2026: From $139
    21

    Fri

  • PDX–ONT, 08/22/2026: From $139
    22

    Sat

  • PDX–ONT, 08/23/2026: From $160
    23

    Sun

  • PDX–ONT, 08/24/2026: From $135
    24

    Mon

  • PDX–ONT, 08/25/2026: From $135
    25

    Tue

  • PDX–ONT: cmp-view-offers-disclaimer. Find Offers
    26

    Wed

  • PDX–ONT, 08/27/2026: From $135
    27

    Thu

  • PDX–ONT, 08/28/2026: From $135
    28

    Fri

  • PDX–ONT, 08/29/2026: From $135
    29

    Sat

  • PDX–ONT: cmp-view-offers-disclaimer. Find Offers
    30

    Sun

  • PDX–ONT, 08/31/2026: From $135
    31

    Mon

  • PDX–ONT, 09/01/2026: From $135
    01

    Tue

    SEP

  • PDX–ONT, 09/02/2026: From $135
    02

    Wed

  • PDX–ONT, 09/03/2026: From $135
    03

    Thu

    • Range$135-$225

    *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 Airport
    Arriving at:
    LA/Ontario International Airport
    Distance:
    838 miles

    Route Information

    147† 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 147 weekly flights from Portland, OR to Ontario/LA on Southwest Airlines.
    To find the lowest fares by day and time to fly Portland, OR 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, OR 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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