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Cheap Flights from Seattle to Apple Valley (SEA-ONT)
Prices were available within the past 7 days and start at $41 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, Aug 28 - Wed, Sep 4
SEA
Seattle
ONT
Ontario
$58 Roundtrip, found 5 hours ago
$58
Roundtrip
found 5 hours ago
![Frontier Airlines](http://images.trvl-media.com/media/content/expus/graphics/static_content/fusion/v0.1b/images/airlines/F9.gif)
Wed, Aug 21 - Wed, Aug 28
SEA
Seattle
ONT
Ontario
$60 Roundtrip, found 6 hours ago
$60
Roundtrip
found 6 hours ago
![Frontier Airlines](http://images.trvl-media.com/media/content/expus/graphics/static_content/fusion/v0.1b/images/airlines/F9.gif)
Tue, Aug 13 - Tue, Aug 20
SEA
Seattle
ONT
Ontario
$62 Roundtrip, found 7 hours ago
$62
Roundtrip
found 7 hours ago
![Frontier Airlines](http://images.trvl-media.com/media/content/expus/graphics/static_content/fusion/v0.1b/images/airlines/F9.gif)
Tue, Sep 3 - Tue, Sep 10
SEA
Seattle
ONT
Ontario
$63 Roundtrip, found 9 hours ago
$63
Roundtrip
found 9 hours ago
![Frontier Airlines](http://images.trvl-media.com/media/content/expus/graphics/static_content/fusion/v0.1b/images/airlines/F9.gif)
Wed, Aug 14 - Tue, Sep 3
SEA
Seattle
ONT
Ontario
$67 Roundtrip, found 4 days ago
$67
Roundtrip
found 4 days ago
![Frontier Airlines](http://images.trvl-media.com/media/content/expus/graphics/static_content/fusion/v0.1b/images/airlines/F9.gif)
Thu, Sep 19 - Wed, Sep 25
SEA
Seattle
ONT
Ontario
$68 Roundtrip, found 5 hours ago
$68
Roundtrip
found 5 hours ago
Nearby Cities
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