Alaska Airlines Flights from Ontario to Seattle

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Lowest fares from Ontario to Seattle

Jun 2025
From$139*
Seen: 1 hour ago
Flight Type One Way|Saver
$89
$453
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Range$89-$453

*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.

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

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One-way low-fare flights Ontario to Seattle.*
From
To
Fare Type
Dates
Price
Ontario (ONT)Seattle (SEA)One-way
|
Saver		Depart: Sep 16, 2025

From

$89

Seen: 1 day ago

Ontario (ONT)Seattle (SEA)One-way
|
Saver		Depart: Jul 29, 2025

From

$89

Seen: 23 hours ago

Ontario (ONT)Seattle (SEA)One-way
|
Saver		Depart: Jul 23, 2025

From

$89

Seen: 20 hours ago

Ontario (ONT)Seattle (SEA)One-way
|
Saver		Depart: Aug 6, 2025

From

$89

Seen: 15 hours ago

Ontario (ONT)Seattle (SEA)One-way
|
Saver		Depart: Sep 2, 2025

From

$89

Seen: 18 hours ago

Ontario (ONT)Seattle (SEA)One-way
|
Saver		Depart: Jul 16, 2025

From

$89

Seen: 12 hours ago

Ontario (ONT)Seattle (SEA)One-way
|
Saver		Depart: Sep 6, 2025

From

$89

Seen: 20 hours ago

Ontario (ONT)Seattle (SEA)One-way
|
Saver		Depart: Jul 22, 2025

From

$89

Seen: 19 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.

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