$139 Cheap Delta flights Ontario Intl. Airport (ONT) to Seattle (SEA)

View $139 flight on Thu, Jun 25, 2026Opens in a new window

$139 Cheap Delta flights Ontario Intl. Airport (ONT) to Seattle (SEA)

Prices were available within the past 7 days and start at $139 for one-way flights and $287 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Delta
Sat, Jul 11 - Sat, Jul 18
ONT
Ontario
SEA
Seattle
$287 Roundtrip, found 1 day ago
$287
Roundtrip
found 1 day ago
Select Delta flight, departing Sat, Jul 11 from Ontario to Seattle, returning Sat, Jul 18, priced at $287 found 1 day ago

Alternative airports near Seattle

Prices were available within the past 7 days. Prices and availability are subject to change.

Select flight to Seattle - Tacoma Intl. SEA. Cheapest option available. Average driving time to city center is 20 minutes. Flights from $260
SEA
Seattle - Tacoma Intl.
Cheapest
Average driving time to city center20 min
Flights from $260

Find the cheapest month to fly from Ontario (ONT) to Seattle (SEA)

June is typically the cheapest month to fly

From $88 - $219 per traveler.

Travel information

Origin airport
Ontario Intl. Airport
Destination airport
Seattle - Tacoma Intl.
Airlines serving
Alaska Airlines, American Airlines, Delta, Frontier Airlines, Southwest Airlines, United
Popular airline
Frontier Airlines
Distance
1530 km
Average flight time
3 hours 9 mins

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