Photo by Ontario Convention & Visitors Bureau / Jon Edwards.

Popular airlines from Seattle-Tacoma International Airport (SEA) to Los Angeles - Ontario Intl. Airport (ONT)
- Alaska Airlines
Alaska Airlines
- Delta
Delta
- United
United
- Frontier Airlines
Frontier Airlines
- Southwest Airlines
Southwest Airlines
- American Airlines
American Airlines
- Hawaiian Airlines
Hawaiian Airlines
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Cheap Flights from Seattle (SEA) to Ontario (ONT)
Prices were available within the past 7 days and start at ฿3,910 for one-way flights and ฿5,815 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Wed, 12 Nov - Sat, 15 Nov
SEA
Seattle
ONT
Ontario
฿5,815 Return, found 4 hours ago
฿5,815
Return
found 4 hours ago

Wed, 12 Nov - Thu, 20 Nov
SEA
Seattle
ONT
Ontario
฿5,870 Return, found 4 hours ago
฿5,870
Return
found 4 hours ago

Thu, 13 Nov - Sat, 15 Nov
SEA
Seattle
ONT
Ontario
฿6,145 Return, found 4 hours ago
฿6,145
Return
found 4 hours ago

Thu, 13 Nov - Thu, 20 Nov
SEA
Seattle
ONT
Ontario
฿6,475 Return, found 4 hours ago
฿6,475
Return
found 4 hours ago

Fri, 14 Nov - Sun, 16 Nov
SEA
Seattle
ONT
Ontario
฿6,500 Return, found 5 days ago
฿6,500
Return
found 5 days ago

Sat, 8 Nov - Wed, 12 Nov
SEA
Seattle
ONT
Ontario
฿7,780 Return, found 4 hours ago
฿7,780
Return
found 4 hours ago

Fri, 14 Nov - Sun, 16 Nov
SEA
Seattle
ONT
Ontario
฿7,985 Return, found 5 days ago
฿7,985
Return
found 5 days ago

Sat, 8 Nov - Sun, 16 Nov
SEA
Seattle
ONT
Ontario
฿8,105 Return, found 4 hours ago
฿8,105
Return
found 4 hours ago

Sat, 25 Oct - Mon, 27 Oct
SEA
Seattle
ONT
Ontario
฿15,625 Return, found 1 day ago
฿15,625
Return
found 1 day ago

Fri, 14 Nov - Sun, 16 Nov
SEA
Seattle
ONT
Ontario
฿17,355 Return, found 5 days ago