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Cheap Flights from Denver to Mascoutah (DEN-STL)
Prices were available within the past 7 days and start at $29 for one-way flights and $58 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.
![Frontier Airlines](http://images.trvl-media.com/media/content/expus/graphics/static_content/fusion/v0.1b/images/airlines/F9.gif)
Wed, Sep 11 - Tue, Sep 17
DEN
Denver
STL
St. Louis
$58 Roundtrip, found 1 hour ago
$58
Roundtrip
found 1 hour ago
![Frontier Airlines](http://images.trvl-media.com/media/content/expus/graphics/static_content/fusion/v0.1b/images/airlines/F9.gif)
Thu, Aug 22 - Thu, Aug 22
DEN
Denver
STL
St. Louis
$63 Roundtrip, found 5 days ago
$63
Roundtrip
found 5 days ago
![United](http://images.trvl-media.com/media/content/expus/graphics/static_content/fusion/v0.1b/images/airlines/UA.gif)
Wed, Sep 11 - Tue, Sep 17
DEN
Denver
STL
St. Louis
$137 Roundtrip, found 1 hour ago
$137
Roundtrip
found 1 hour ago
![American Airlines](http://images.trvl-media.com/media/content/expus/graphics/static_content/fusion/v0.1b/images/airlines/AA.gif)
Tue, Jul 16 - Tue, Jul 23
DEN
Denver
STL
St. Louis
$168 Roundtrip, found 22 hours ago
$168
Roundtrip
found 22 hours ago
![Delta](http://images.trvl-media.com/media/content/expus/graphics/static_content/fusion/v0.1b/images/airlines/DL.gif)
Sat, Nov 16 - Sat, Nov 16
DEN
Denver
STL
St. Louis
$171 Roundtrip, found 1 day ago
$171
Roundtrip
found 1 day ago
Fri, Oct 18 - Mon, Oct 21
DEN
Denver
STL
St. Louis
$223 Roundtrip, found 4 days ago
$223
Roundtrip
found 4 days ago
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