Alaska Airlines Flights from Saint Louis to Seattle

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Lowest fares from Saint Louis to Seattle

$125
$344
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  • Range$125-$344

    One-way low-fare flights Saint Louis to Seattle.*

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    One-way low-fare flights Saint Louis to Seattle.*
    From
    To
    Fare Type
    Dates
    Price
    Saint Louis (STL)Seattle (SEA)One-way
    |
    Saver
    Depart: Jan 23, 2026

    From

    $71

    Seen: 15 hours ago

    Saint Louis (STL)Seattle (SEA)One-way
    |
    Saver
    Depart: Oct 31, 2025

    From

    $119

    Seen: 5 hours ago

    Saint Louis (STL)Seattle (SEA)One-way
    |
    Saver
    Depart: Aug 31, 2025

    From

    $119

    Seen: 5 hours ago

    Saint Louis (STL)Seattle (SEA)One-way
    |
    Saver
    Depart: Oct 15, 2025

    From

    $125

    Seen: 5 hours ago

    Saint Louis (STL)Seattle (SEA)One-way
    |
    Saver
    Depart: Oct 20, 2025

    From

    $125

    Seen: 5 hours ago

    Saint Louis (STL)Seattle (SEA)One-way
    |
    Saver
    Depart: Oct 23, 2025

    From

    $125

    Seen: 5 hours ago

    Saint Louis (STL)Seattle (SEA)One-way
    |
    Saver
    Depart: Oct 24, 2025

    From

    $125

    Seen: 5 hours ago

    Saint Louis (STL)Seattle (SEA)One-way
    |
    Saver
    Depart: Oct 27, 2025

    From

    $125

    Seen: 5 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.