£32 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 £32 for one-way flights and £63 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 route information
Origin airport
Seattle - Tacoma Intl.
Destination airport
Los Angeles - Ontario Intl.
Airlines serving
Alaska Airlines, American Airlines, Delta, Frontier Airlines, United
Return price
£63
Distance
1530 km

Compare flights from Seattle to Ontario easily and book in confidence

For travelling on business or for pleasure, Expedia makes it easy to book your flights from Seattle to Ontario. Operating between them 17 flights per day, 20 airlines cover the route. And KLM, Qatar Airways, JAL, Alaska Airlines, Frontier Airlines, Delta Air Lines, Korean Air, WestJet, Virgin Atlantic fly direct, getting you to Los Angeles - Ontario Intl. in just 2hours. If you have a preferred carrier, use our advanced search tool to find the right flight from Seattle - Tacoma Intl. to Los Angeles - Ontario Intl..  

To make things even better, in the advanced search, you can also choose to fly economy, premium economy, business or first class, select your maximum number of stops, and pick your preferred departure and arrival time. You can also opt for refundable and direct flights. 

Grab a great deal on your flight from Seattle - Tacoma Intl. (SEA) to Los Angeles - Ontario Intl. (ONT) 

The easiest way to view the best deals on flights from Seattle to Ontario today is to enter your travel dates and hit search. From here, you can sort your results by price to see the cheapest flights first. Right now, return flights from Seattle - Tacoma Intl. to Los Angeles - Ontario Intl. start at just £63 and range up to £93.  

To find an even better deal, try  

  • being flexible on your dates – midweek flights can be cheaper
  • looking for other airports near Seattle and Ontario
  • booking your flight during August, the cheapest month on this route
  • varying your flight times – early morning and late at night are sometimes cheaper 

Why you should book your Seattle to Ontario flight with Expedia!

We cater for all flight types, cabin classes and airlines. So whether you’re booking flights from Seattle - Tacoma Intl. to Los Angeles - Ontario Intl. for a budget break or a business trip with a bit of pleasure thrown in, we make it easy to secure the seat that’s right for you.  

Thanks to our supersized inventory that offers great choice all in one place, you know you’ll get a great deal with Expedia. Especially if you bundle your flight together with your hotel, you will unlock amazing savings. For added peace of mind, you can choose flexible bookings or filter to find refundable options, so you won’t pay a fee to change your flight.  

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 £63. 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 cancelled 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 kilometres. 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 Airports

Los Angeles

Orange County

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