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S$180 Cheap Flights from Seattle to Ontario Intl. Airport

View S$180 flight on Tue, 25 Aug, 2026Opens in a new window

Popular airlines from Seattle-Tacoma International Airport (SEA) to Ontario Intl. Airport (ONT)

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Cheap Flights from Seattle to Ontario Intl. Airport (SEA-ONT)

Prices were available within the past 7 days and start at S$180 for one-way flights and S$281 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Delta
Tue, 25 Aug - Tue, 1 Sept
SEA
Seattle
ONT
Ontario
S$281 Return, found 2 days ago
S$281
Return
found 2 days ago
Select Delta flight, departing Tue, 25 Aug from Seattle to Ontario, returning Tue, 1 Sept, priced at S$281 found 2 days ago
Delta
Tue, 25 Aug - Tue, 1 Sept
SEA
Seattle
ONT
Ontario
S$359 Return, found 2 days ago
S$359
Return
found 2 days ago
Select Delta flight, departing Tue, 25 Aug from Seattle to Ontario, returning Tue, 1 Sept, priced at S$359 found 2 days ago
Delta
Mon, 3 Aug - Mon, 24 Aug
SEA
Seattle
ONT
Ontario
S$378 Return, found 5 days ago
S$378
Return
found 5 days ago
Select Delta flight, departing Mon, 3 Aug from Seattle to Ontario, returning Mon, 24 Aug, priced at S$378 found 5 days ago
United
Tue, 25 Aug - Tue, 1 Sept
SEA
Seattle
ONT
Ontario
S$385 Return, found 2 days ago
S$385
Return
found 2 days ago
Select United flight, departing Tue, 25 Aug from Seattle to Ontario, returning Tue, 1 Sept, priced at S$385 found 2 days ago
Delta
Tue, 25 Aug - Tue, 1 Sept
SEA
Seattle
ONT
Ontario
S$398 Return, found 2 days ago
S$398
Return
found 2 days ago
Select Delta flight, departing Tue, 25 Aug from Seattle to Ontario, returning Tue, 1 Sept, priced at S$398 found 2 days ago
United
Tue, 25 Aug - Tue, 1 Sept
SEA
Seattle
ONT
Ontario
S$404 Return, found 2 days ago
S$404
Return
found 2 days ago
Select United flight, departing Tue, 25 Aug from Seattle to Ontario, returning Tue, 1 Sept, priced at S$404 found 2 days ago
American Airlines
Tue, 25 Aug - Tue, 1 Sept
SEA
Seattle
ONT
Ontario
S$410 Return, found 2 days ago
S$410
Return
found 2 days ago
Select American Airlines flight, departing Tue, 25 Aug from Seattle to Ontario, returning Tue, 1 Sept, priced at S$410 found 2 days ago
United
Tue, 25 Aug - Tue, 1 Sept
SEA
Seattle
ONT
Ontario
S$417 Return, found 2 days ago
S$417
Return
found 2 days ago
Select United flight, departing Tue, 25 Aug from Seattle to Ontario, returning Tue, 1 Sept, priced at S$417 found 2 days ago
United
Tue, 25 Aug - Tue, 1 Sept
SEA
Seattle
ONT
Ontario
S$423 Return, found 2 days ago
S$423
Return
found 2 days ago
Select United flight, departing Tue, 25 Aug from Seattle to Ontario, returning Tue, 1 Sept, priced at S$423 found 2 days ago
United
Tue, 25 Aug - Tue, 1 Sept
SEA
Seattle
ONT
Ontario
S$430 Return, found 2 days ago
S$430
Return
found 2 days ago
Select United flight, departing Tue, 25 Aug from Seattle to Ontario, returning Tue, 1 Sept, priced at S$430 found 2 days ago

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 S$281. 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.

Travel information

Origin airport
Seattle - Tacoma Intl.
Destination airport
Ontario Intl. Airport
Airlines serving
American Airlines, Delta, United
Return price
S$281
Distance
1530 km
Average flight time
2 hours 55 mins

Book with confidence

Perfect flights from Seattle to Ontario Intl. Airport

Your Journey from Seattle to Ontario Intl. Airport

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Choosing Your Ideal Flight

With Expedia, you have access to a wide range of airlines, including Delta, United, American Airlines, Alaska Airlines. Our selection of flights from Seattle - Tacoma Intl. to Ontario Intl. Airport caters to every traveler's requirements, ensuring your journey aligns with your schedule. With options from 20 airlines, you're bound to find the perfect flight.
 

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Experience the joy of finding cheap flights from Seattle - Tacoma Intl. to Ontario Intl. Airport that fit your budget. Keep an eye out for our special deals and discounts, and check our flexible one-way fares from S$180 and roundtrip prices from S$281*.
 

Pre-Flight Essentials

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Experience the Vibrant Ontario Intl. Airport

Picture yourself stepping off the plane in Ontario Intl. Airport and immersing yourself in the unique atmosphere of . From local markets to cultural festivals, each city offers its distinct charm. Make the most of your trip by exploring local attractions and indulging in the local cuisine. With Expedia, explore all this and more, tailored to your budget.
 

Added Convenience on Your Seattle to Ontario Intl. Airport Flight

Traveling with Expedia is more than just a flight. We offer details about in-flight amenities, baggage policies, and more to ensure a smooth and hassle-free journey. Choose from our variety of airlines and embark on a memorable journey from Seattle to Ontario Intl. Airport.
 

Beyond the Flight – Exploring Ontario Intl. Airport

With Expedia, your adventure extends beyond the flight. Explore Ontario Intl. Airport at your own pace by renting a car or booking a hotel. Discover hidden gems off the beaten path and create unforgettable memories.
 

Book Your Flight from Seattle to Ontario Intl. Airport with Confidence

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*Note: Prices may vary based on availability and are subject to change.
Perfect flights from Seattle to Ontario Intl. Airport

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