Alaska Airlines Flights from Seattle to Ontario

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Lowest fares from Seattle to Ontario

Jul 2025
From$88*
Seen: 4 hours ago
Flight Type One Way|Saver
$88
$299
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    • Range$88-$299

    *Displayed prices have been available within the past 24 hours and may not be available at the time of booking. Fares listed may be Saver fares, which is our most restrictive fare option and subject to additional restrictions. For roundtrip journeys, the price displayed—available within the past 24 hours—is the aggregate of the lowest available fare each way. Additional baggage charges and fees for optional products and services may apply. Other terms and conditions may apply.

    One-way low-fare flights Seattle to Ontario.*

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    One-way low-fare flights Seattle to Ontario.*
    From
    To
    Fare Type
    Dates
    Price
    Seattle (SEA)Ontario (ONT)One-way
    |
    Saver    		Depart: Aug 26, 2025

    From

    $88

    Seen: 11 hours ago

    Seattle (SEA)Ontario (ONT)One-way
    |
    Saver    		Depart: Aug 27, 2025

    From

    $88

    Seen: 11 hours ago

    Seattle (SEA)Ontario (ONT)One-way
    |
    Saver    		Depart: Jul 30, 2025

    From

    $88

    Seen: 4 hours ago

    Seattle (SEA)Ontario (ONT)One-way
    |
    Saver    		Depart: Aug 5, 2025

    From

    $88

    Seen: 11 hours ago

    Seattle (SEA)Ontario (ONT)One-way
    |
    Saver    		Depart: Aug 19, 2025

    From

    $88

    Seen: 11 hours ago

    Seattle (SEA)Ontario (ONT)One-way
    |
    Saver    		Depart: Jul 29, 2025

    From

    $88

    Seen: 3 hours ago

    Seattle (SEA)Ontario (ONT)One-way
    |
    Saver    		Depart: Sep 9, 2025

    From

    $98

    Seen: 11 hours ago

    Seattle (SEA)Ontario (ONT)One-way
    |
    Saver    		Depart: Aug 31, 2025

    From

    $98

    Seen: 11 hours ago

    *Displayed prices have been available within the past 24 hours and may not be available at the time of booking. Fares listed may be Saver fares, which is our most restrictive fare option and subject to additional restrictions. For roundtrip journeys, the price displayed—available within the past 24 hours—is the aggregate of the lowest available fare each way. Additional baggage charges and fees for optional products and services may apply. Other terms and conditions may apply.

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