Alaska Airlines Flights from Philadelphia to Seattle

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Lowest fares from Philadelphia to Seattle

May 2025
From$139*
Seen: 51 minutes ago
Flight Type One Way|Saver
$139
$494
Displaying fares for May-2025
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Range$139-$494

*Fares and availability are based on round trip searches for 1 passenger (1 adult) in Economy class in the last 48 hours. Fares are inclusive of tax and surcharges, and subject to availability.

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

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One-way low-fare flights Philadelphia to Seattle.*
From
To
Fare Type
Dates
Price
Philadelphia (PHL)Seattle (SEA)One-way
|
Saver		Depart: May 28, 2025

From

$139

Seen: 51 minutes ago

Philadelphia (PHL)Seattle (SEA)One-way
|
Saver		Depart: Nov 9, 2025

From

$149

Seen: 1 day ago

Philadelphia (PHL)Seattle (SEA)One-way
|
Saver		Depart: Sep 26, 2025

From

$149

Seen: 23 hours ago

Philadelphia (PHL)Seattle (SEA)One-way
|
Saver		Depart: Aug 27, 2025

From

$149

Seen: 3 hours ago

Philadelphia (PHL)Seattle (SEA)One-way
|
Saver		Depart: Sep 6, 2025

From

$149

Seen: 1 day ago

Philadelphia (PHL)Seattle (SEA)One-way
|
Saver		Depart: Sep 4, 2025

From

$149

Seen: 20 hours ago

Philadelphia (PHL)Seattle (SEA)One-way
|
Saver		Depart: Oct 16, 2025

From

$149

Seen: 7 hours ago

Philadelphia (PHL)Seattle (SEA)One-way
|
Saver		Depart: Sep 5, 2025

From

$149

Seen: 1 hour ago

*Prices have been available for one-way trips within the last 48 hours and may not be currently available. Fares listed may be Saver fares which is our most restrictive fare option and subject to additional restrictions. Additional baggage charges and fees for optional products and services may apply. Other terms and conditions may apply.

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