Flights from Seattle, WA to Ontario/LA, CA

Promo Code

Best Deals on Flights From Seattle, WA (SEA) to Ontario/LA, CA (ONT)

Aug 2026
from$50*
Last seen: 11 hours ago
One-way/Economy
Sep 2026
from$36*
Last seen: 9 hours ago
One-way/Economy
Oct 2026
from$93*
Last seen: 7 hours ago
One-way/Economy
cmp-daily-histogram-bars-legend-min-price-aria-label $36
cmp-daily-histogram-bars-legend-max-price-aria-label $185
Displaying fares for August-2026
  • SEA–ONT: cmp-view-offers-disclaimer. Find Offers
    24

    Mon

    AUG

  • SEA–ONT: cmp-view-offers-disclaimer. Find Offers
    25

    Tue

  • SEA–ONT, Aug 26, 2026: from $50
    26

    Wed

  • SEA–ONT, Aug 27, 2026: from $92
    27

    Thu

  • SEA–ONT, Aug 28, 2026: from $92
    28

    Fri

  • SEA–ONT, Aug 29, 2026: from $81
    29

    Sat

  • SEA–ONT, Aug 30, 2026: from $185
    30

    Sun

  • SEA–ONT, Aug 31, 2026: from $162
    31

    Mon

  • SEA–ONT, Sep 1, 2026: from $100
    01

    Tue

    SEP

  • SEA–ONT, Sep 2, 2026: from $100
    02

    Wed

  • SEA–ONT, Sep 3, 2026: from $142
    03

    Thu

  • SEA–ONT, Sep 4, 2026: from $169
    04

    Fri

  • SEA–ONT, Sep 5, 2026: from $36
    05

    Sat

  • SEA–ONT, Sep 6, 2026: from $137
    06

    Sun

  • SEA–ONT, Sep 7, 2026: from $169
    07

    Mon

  • SEA–ONT: cmp-view-offers-disclaimer. Find Offers
    08

    Tue

  • SEA–ONT, Sep 9, 2026: from $137
    09

    Wed

  • SEA–ONT, Sep 10, 2026: from $137
    10

    Thu

  • SEA–ONT, Sep 11, 2026: from $137
    11

    Fri

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

    Sat

  • SEA–ONT: cmp-view-offers-disclaimer. Find Offers
    13

    Sun

  • SEA–ONT: cmp-view-offers-disclaimer. Find Offers
    14

    Mon

  • SEA–ONT: cmp-view-offers-disclaimer. Find Offers
    15

    Tue

  • SEA–ONT: cmp-view-offers-disclaimer. Find Offers
    16

    Wed

  • SEA–ONT, Sep 17, 2026: from $108
    17

    Thu

  • SEA–ONT, Sep 18, 2026: from $108
    18

    Fri

  • SEA–ONT, Sep 19, 2026: from $85
    19

    Sat

  • SEA–ONT, Sep 20, 2026: from $108
    20

    Sun

  • SEA–ONT, Sep 21, 2026: from $101
    21

    Mon

  • SEA–ONT: cmp-view-offers-disclaimer. Find Offers
    22

    Tue

  • SEA–ONT, Sep 23, 2026: from $70
    23

    Wed

    • Range$36-$185

    *Prices found by others in the previous 48 hours for round-trip flights. Prices shown may also require membership in our travel club, Discount Den.

    Flights Deals from Seattle, WA to Ontario/LA, CA on Frontier

    $
    Flights Deals from Seattle, WA to Ontario/LA, CA on Frontier
    From
    To
    Seattle, WA (SEA)Ontario/LA, CA (ONT)One-way
    /
    Discount Den Basic Fare    		Departing Nov 22, 2026

    From

    $98

    Last seen: 3 hours ago

    *Prices found by others in the previous 48 hours for one-way flights. Prices shown may also require membership in our travel club, Discount Den®.

    Seattle, WA Ontario/LA, CA

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