Flights to San Juan Island from St. Louis - $70

View $70 flight on Mon, Sep 29, 2025Opens in a new window

Popular airlines from St. Louis to San Juan Island

  • American Airlines

    American Airlines

  • United

    United

  • Southwest Airlines

    Southwest Airlines

  • Delta

    Delta

  • Frontier Airlines

    Frontier Airlines

  • JetBlue Airways

    JetBlue Airways

  • Alaska Airlines

    Alaska Airlines

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Cheap Flights from St. Louis to San Juan Island (STL-SEA)

Prices were available within the past 7 days and start at $70 for one-way flights and $140 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Southwest Airlines
Mon, Sep 1 - Sat, Sep 6
STL
St. Louis
SEA
Seattle
$140 Roundtrip, found 8 hours ago
$140
Roundtrip
found 8 hours ago
Select Southwest Airlines flight, departing Mon, Sep 1 from St. Louis to Seattle, returning Sat, Sep 6, priced at $140 found 8 hours ago
Southwest Airlines
Mon, Sep 29 - Tue, Oct 7
STL
St. Louis
SEA
Seattle
$145 Roundtrip, found 2 hours ago
$145
Roundtrip
found 2 hours ago
Select Southwest Airlines flight, departing Mon, Sep 29 from St. Louis to Seattle, returning Tue, Oct 7, priced at $145 found 2 hours ago
United
Mon, Sep 22 - Tue, Sep 30
STL
St. Louis
SEA
Seattle
$150 Roundtrip, found 2 hours ago
$150
Roundtrip
found 2 hours ago
Select United flight, departing Mon, Sep 22 from St. Louis to Seattle, returning Tue, Sep 30, priced at $150 found 2 hours ago
American Airlines
Fri, Sep 5 - Tue, Sep 16
STL
St. Louis
SEA
Seattle
$159 Roundtrip, just found
$159
Roundtrip
just found
Select American Airlines flight, departing Fri, Sep 5 from St. Louis to Seattle, returning Tue, Sep 16, priced at $159 just found
Delta
Sun, Aug 31 - Tue, Sep 9
STL
St. Louis
SEA
Seattle
$243 Roundtrip, found 1 hour ago
$243
Roundtrip
found 1 hour ago
Select Delta flight, departing Sun, Aug 31 from St. Louis to Seattle, returning Tue, Sep 9, priced at $243 found 1 hour ago
Alaska Airlines
Sun, Aug 31 - Tue, Sep 9
STL
St. Louis
SEA
Seattle
$243 Roundtrip, found 1 hour ago
$243
Roundtrip
found 1 hour ago
Select Alaska Airlines flight, departing Sun, Aug 31 from St. Louis to Seattle, returning Tue, Sep 9, priced at $243 found 1 hour ago
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