Popular airlines from Seattle-Tacoma International Airport (SEA) to Los Angeles - Ontario Intl. Airport (ONT)
Alaska AirlinesAlaska Airlines
DeltaDelta
Frontier AirlinesFrontier Airlines
UnitedUnited
Southwest AirlinesSouthwest Airlines
American AirlinesAmerican Airlines
Hawaiian AirlinesHawaiian Airlines
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Today's featured flight deals from Seattle-Tacoma International Airport (SEA) to Los Angeles - Ontario Intl. Airport (ONT)
- Seattle (SEA) to Ontario (ONT).Frontier Airlines, nonstop.Departing on Thu, Aug 28 at 1:20pm from Seattle, arriving at 4:14pm in Ontario.Returning on Mon, Sep 1 at 7:00am from Ontario, arriving at 12:33pm in Seattle.Select Frontier Airlines flight departing on Thu, Aug 28 at 1:20pm from Seattle, returning on Mon, Sep 1 at 7:00am from Ontario priced at $22055% less than typical$220
- Seattle (SEA) to Ontario (ONT).Delta, nonstop.Departing on Thu, Aug 28 at 8:05am from Seattle, arriving at 10:50am in Ontario.Returning on Mon, Sep 1 at 7:00am from Ontario, arriving at 12:33pm in Seattle.Select Delta flight departing on Thu, Aug 28 at 8:05am from Seattle, returning on Mon, Sep 1 at 7:00am from Ontario priced at $25445% less than typical$254
- Seattle (SEA) to Ontario (ONT).Frontier Airlines, nonstop.Departing on Sat, Aug 23 at 8:27pm from Seattle, arriving at 11:09pm in Ontario.Returning on Thu, Aug 28 at 12:59am from Ontario, arriving at 9:34am in Seattle.Select Frontier Airlines flight departing on Sat, Aug 23 at 8:27pm from Seattle, returning on Thu, Aug 28 at 12:59am from Ontario priced at $26240% less than typical$262
- Seattle (SEA) to Ontario (ONT).Frontier Airlines, nonstop.Departing on Tue, Sep 2 at 8:42pm from Seattle, arriving at 11:24pm in Ontario.Returning on Tue, Sep 9 at 9:55am from Ontario, arriving at 2:10pm in Seattle.Select Frontier Airlines flight departing on Tue, Sep 2 at 8:42pm from Seattle, returning on Tue, Sep 9 at 9:55am from Ontario priced at $17650% less than typical$176
- Seattle (SEA) to Ontario (ONT).Frontier Airlines, nonstop.Departing on Sat, Aug 23 at 8:27pm from Seattle, arriving at 11:09pm in Ontario.Returning on Sat, Aug 30 at 4:56pm from Ontario, arriving at 7:42pm in Seattle.Select Frontier Airlines flight departing on Sat, Aug 23 at 8:27pm from Seattle, returning on Sat, Aug 30 at 4:56pm from Ontario priced at $25840% less than typical$258
- Seattle (SEA) to Ontario (ONT).Frontier Airlines, nonstop.Departing on Sun, Sep 7 at 12:05pm from Seattle, arriving at 2:53pm in Ontario.Returning on Thu, Sep 11 at 8:10am from Ontario, arriving at 12:35pm in Seattle.Select Frontier Airlines flight departing on Sun, Sep 7 at 12:05pm from Seattle, returning on Thu, Sep 11 at 8:10am from Ontario priced at $24340% less than typical$243
- Seattle (SEA) to Ontario (ONT).Frontier Airlines, nonstop.Departing on Tue, Aug 26 at 8:42pm from Seattle, arriving at 11:24pm in Ontario.Returning on Thu, Sep 4 at 8:13am from Ontario, arriving at 11:11am in Seattle.Select Frontier Airlines flight departing on Tue, Aug 26 at 8:42pm from Seattle, returning on Thu, Sep 4 at 8:13am from Ontario priced at $18245% less than typical$182
- Seattle (SEA) to Ontario (ONT).Frontier Airlines, nonstop.Departing on Sun, Aug 31 at 1:20pm from Seattle, arriving at 4:14pm in Ontario.Returning on Wed, Sep 3 at 7:10pm from Ontario, arriving on Thu, Sep 4 at 12:05am in Seattle.Select Frontier Airlines flight departing on Sun, Aug 31 at 1:20pm from Seattle, returning on Wed, Sep 3 at 7:10pm from Ontario priced at $28835% less than typical$288
- Seattle (SEA) to Ontario (ONT).Frontier Airlines, nonstop.Departing on Thu, Aug 28 at 1:20pm from Seattle, arriving at 4:14pm in Ontario.Returning on Mon, Sep 1 at 12:59am from Ontario, arriving at 9:34am in Seattle.Select Frontier Airlines flight departing on Thu, Aug 28 at 1:20pm from Seattle, returning on Mon, Sep 1 at 12:59am from Ontario priced at $25235% less than typical$252
Cheap Flights from Seattle to Ontario (SEA-ONT)
Prices were available within the past 7 days and start at $60 for one-way flights and $110 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.
Find the cheapest month to fly from Seattle (SEA) to Ontario (ONT)
October is typically the cheapest month to fly
Graph displaying average flight prices per month
Alternative airports near Ontario
Prices were available within the past 7 days. Prices and availability are subject to change.
Origin airport | Seattle - Tacoma Intl. |
Destination airport | Los Angeles - Ontario Intl. |
Airlines serving | Alaska Airlines, American Airlines, Delta, Frontier Airlines, Hawaiian Airlines, Southwest Airlines, United |
Roundtrip price | $110 |
Distance | 956 mi |
Average flight time | 2 hours 55 mins |
Seattle to Ontario Flights
The cheapest times to fly from Seattle to Ontario
On average, Thursday can be the cheapest time to fly, according to data from the Airlines Reporting Corporation (ARC), one of the world's biggest databases for global airline sales. The data reveals that you could save up to 16% by flying on a Thursday—the cheapest day to travel on average—instead of a Sunday—the most expensive. Some of the most affordable flights from Seattle to Ontario are during the month of October. You can find some of the cheapest flights from Seattle to Ontario with Expedia's search tool and vast selection of airlines.
The best time to book a flight from Seattle to Ontario
Sunday is one of the best days to book for cheap flights from Seattle to Ontario: Tickets reserved on a Sunday cost between 6% and 13% less than those reserved on a Friday, according to ARC data. The data also suggests booking early can also lead to cheaper airfares. You could save 24% by buying your tickets for domestic flights at least a month in advance and 10% by booking international flights 2 months in advance.
How to find cheap round-trip tickets from Seattle to Ontario
Being flexible with your dates and using Expedia's Price Drop Protection and Price Tracking features are some of the best ways of finding a cheap ticket from Seattle to Ontario in 2025. You can also book with separate airlines for your outbound and return journeys, from $60 one-way. Expedia also offers Price Drop Protection, so if the cost of your airfare goes down after booking, you'll receive a credit for the difference*. This is available for a small fee, and is free to One Key Gold and Platinum tier members.
Expedia's Price Tracking feature means you can stay on top of airfares without manually checking every day. It sends you automated price alerts for cheap Seattle to Ontario flights and uses historical data to indicate when the best time to book is. Download Expedia's free app to activate this handy tool in a few easy taps.
You could also save big by booking one of Expedia's vacation packages. Bundling together your Seattle to Ontario airfare with your accommodations and car rental is often cheaper than booking everything separately. There’s also One Key, Expedia's generous rewards program. Join for free and you could earn One Key cash on most bookings to save on future adventures.
*Terms apply.
Disclaimer: ARC The statistics are based on average round-trip ticket prices between January and August 2023. The percentages you see are averages.
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Lodging
- Hotels near Ontario Convention Center
- Hotels near Cucamonga-Guasti Regional Park
- Hotels near Guasti
- Resorts & Hotels with Spas in Guasti
- Hotels with a View in Guasti
- Hotels near Disneyland® Resort
- Ontario Hotels
- Hotels near Toyota Arena
- Hotels near East Ontario Station
- Rancho Cucamonga Hotels
- Hotels near Ontario Mills Shopping Mall
- Hotels near Scandia Amusement Park
- Hotels near Villaggio Nail Spa
- Cheap Hotels in Ontario
- Hotels near Rancho Cucamonga Station
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- Hotels with Free Airport Shuttle in Ontario
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