$89 Cheap United flights Seattle (SEA) to Ontario (ONT)

View $89 flight on Sat, Aug 16, 2025Opens in a new window

$89 Cheap United flights Seattle (SEA) to Ontario (ONT)

Prices were available within the past 7 days and start at $89 for one-way flights and $177 for roundtrip, for the period specified. Prices and availability are subject to change. Additional terms apply.
United
Sat, Aug 23 - Tue, Aug 26
SEA
Seattle
ONT
Ontario
$177
Roundtrip
Found 23 hours ago
Select United flight, departing Sat, Aug 23 from Seattle to Ontario, returning Tue, Aug 26, priced at $177 Found 23 hours ago
United
Thu, Aug 28 - Sun, Aug 31
SEA
Seattle
ONT
Ontario
$199
Roundtrip
Found 23 hours ago
Select United flight, departing Thu, Aug 28 from Seattle to Ontario, returning Sun, Aug 31, priced at $199 Found 23 hours ago
United
Sat, Aug 23 - Tue, Aug 26
SEA
Seattle
ONT
Ontario
$247
Roundtrip
Found 23 hours ago
Select United flight, departing Sat, Aug 23 from Seattle to Ontario, returning Tue, Aug 26, priced at $247 Found 23 hours ago
United
Sat, Aug 23 - Tue, Aug 26
SEA
Seattle
ONT
Ontario
$267
Roundtrip
Found 23 hours ago
Select United flight, departing Sat, Aug 23 from Seattle to Ontario, returning Tue, Aug 26, priced at $267 Found 23 hours ago
United
Sat, Aug 23 - Tue, Aug 26
SEA
Seattle
ONT
Ontario
$270
Roundtrip
Found 23 hours ago
Select United flight, departing Sat, Aug 23 from Seattle to Ontario, returning Tue, Aug 26, priced at $270 Found 23 hours ago
Flights from Seattle (SEA) to Ontario (ONT)
Origin airport
Seattle - Tacoma Intl.
Destination airport
Los Angeles - Ontario Intl.
Airlines serving
Alaska Airlines, American Airlines, Delta, Frontier Airlines, Hawaiian Airlines, United
Popular airline
Frontier Airlines
Distance
1530 km
Average flight time
2 hours 54 mins