Alaska Airlines Flights from Ontario to Seattle

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Lowest fares from Ontario to Seattle

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: Feb 18, 2026

From

$98

Seen: 1 day ago

Ontario (ONT)Seattle (SEA)One-way
|
Saver
Depart: Oct 18, 2025

From

$98

Seen: 1 day ago

Ontario (ONT)Seattle (SEA)One-way
|
Saver
Depart: Oct 25, 2025

From

$98

Seen: 1 day ago

Ontario (ONT)Seattle (SEA)One-way
|
Saver
Depart: Feb 24, 2026

From

$98

Seen: 1 day ago

Ontario (ONT)Seattle (SEA)One-way
|
Saver
Depart: Feb 25, 2026

From

$98

Seen: 1 day ago

Ontario (ONT)Seattle (SEA)One-way
|
Saver
Depart: Feb 28, 2026

From

$98

Seen: 1 day ago

Ontario (ONT)Seattle (SEA)One-way
|
Saver
Depart: Mar 3, 2026

From

$98

Seen: 1 day ago

Ontario (ONT)Seattle (SEA)One-way
|
Saver
Depart: Mar 4, 2026

From

$98

Seen: 1 day 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.