CA $121 Cheap Flights from Seattle (SEA) to Ontario (ONT)

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Cheap flights from Seattle (SEA) to Ontario (ONT)

Prices were available within the past 7 days and start at CA $121 for one-way flights and CA $73 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Frontier Airlines
Frontier Airlines
Frontier Airlines
Frontier Airlines
Frontier Airlines
Frontier Airlines
Frontier Airlines
Frontier Airlines
Frontier Airlines
Frontier Airlines
Flight from Seattle to Ontario (SEA - ONT) route information
Origin airport
Seattle - Tacoma Intl.
Destination airport
Los Angeles - Ontario Intl.
Airlines serving
Alaska Airlines, American Airlines, Delta, Frontier Airlines, United
Roundtrip price
CA $73
Distance
1530 km
Average flight time
2 hours 34 mins

Seattle to Los Angeles Flights

The easy way to book your flights from Seattle to Ontario 

With Expedia, it’s simple to find and book flights to Ontario from Seattle whether you’re traveling for business or pleasure. Enter your travel dates, hit search, and choose your flight from 20 airlines that cover this route. There are Qatar Airways, KLM, JAL, Alaska Airlines, Delta Air Lines, Korean Air, WestJet, Virgin Atlantic nonstop flights to Los Angeles - Ontario Intl., too.  

Choose your preferred carrier and cabin class with the advanced search tool and select your ideal departure time. Then, if you want, you can see just nonstop or refundable flights. And if you’re traveling last minute, just enter the date to check out flights from Seattle to Ontario today, tomorrow, or this week.  

 

Save dollars with cheap flights from Seattle - Tacoma Intl., SEA to Los Angeles - Ontario Intl., ONT 

Sort your search results by price to find great deals on your flight from Seattle to Ontario—you get all your cheapest options first. Grab yourself a bargain now—the lowest price on flights to Ontario from Seattle currently is just CA $73 rising to CA $119.  

Here are more money-saving tips: 

  • Fly in May when flight prices are normally at their lowest 
  • Book about a month to 6 weeks before you travel for the best prices to Ontario  
  • Avoid peak season and weekends when flights can cost more
  • Early morning and late-night flights are sometimes cheaper, so try varying your travel times 
  • One surefire way to save money on your flight is to book your flight and hotel together with Expedia. Sometimes, the savings are so large that the flight is basically free! 

 

Reasons to choose Expedia for your flight to Ontario from Seattle 

Whatever your destination, budget, or reason to travel, in just one quick search, you can choose from loads of flights, airlines, and cabin classes. The filters make it quick and easy to find your ideal flights, and if you choose one of the flexible options, you won’t be charged to change your flight. So book your flight to Ontario with Expedia today.

Frequently asked questions

How much is a flight from Seattle - Tacoma Intl. Airport (SEA) to ONT?
Based on airfares available within the last 7 days on Expedia for flights departing within the next year, round-trip flights between Sea-Tac Airport and Los Angeles - Ontario Intl. Airport (ONT) start from CA $73. Make your booking ASAP to score the best price for your big adventure. Prices and availability are subject to change. Additional terms apply.
Do I need to pay a cancellation fee if I cancel my flight from SEA to Los Angeles - Ontario Intl. Airport (ONT)?
The majority of flights can be canceled online, but every airline has its own set of terms and conditions. If you do need to cancel your flight, check out our Customer Service Portal and follow the instructions.
How do I find cheap flights from SEA to Los Angeles - Ontario Intl. Airport (ONT) that have flexible change policies?
Many airlines offer the option to reschedule your flight without a change fee. All you pay is the difference between the original flight and the new flight. When you’re searching for Seattle - Tacoma Intl. Airport (SEA) to Los Angeles - Ontario Intl. Airport (ONT) flights, you’ll see a “no change fees” filter for you to select.
How far is the flight from Sea-Tac Airport to ONT?
The flying distance between Sea-Tac Airport and Los Angeles - Ontario Intl. Airport (ONT) is 1,550 kilometers. Close your eyes or get stuck into a book and the journey will zip on by.
Which airlines fly direct from Sea-Tac Airport to Ontario Airport?
One airline that services the route from Seattle - Tacoma Intl. Airport (SEA) to Los Angeles - Ontario Intl. Airport (ONT) is Alaska Airlines (AS). It offers 117 flights every month. Another carrier servicing this route is Delta Air Lines (DL). You’ll have 86 flights each month to select from.
Are SEA to ONT flight tickets cheaper when they're purchased at the last minute?
It is possible to nab a fantastic last-minute deal from SEA to Ontario Airport, but it can also be hit-or-miss. As many airlines release prices up to a year in advance, it’s worthwhile keeping an eye on fares early and being ready to book when you see a bargain. Expedia compares carrier prices and updates flight deals often, so you can rest easy knowing you’re always getting the latest offers.
Ontario nearby Airports

Orange County

Los Angeles

Long Beach

Seattle nearby Airports

Seattle Paine Field Intl. Airport

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