S$106 Cheap Flights from Ontario to Seattle

View S$106 flight on Tue, 3 Jun, 2025Opens in a new window

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Cheap Flights from Ontario to Seattle (ONT-SEA)

Prices were available within the past 7 days and start at S$106 for one-way flights and S$227 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Delta
Thu, 29 May - Tue, 10 Jun
ONT
Ontario
SEA
Seattle
S$227 Return, found 4 days ago
S$227
Return
found 4 days ago
Select Delta flight, departing Thu, 29 May from Ontario to Seattle, returning Tue, 10 Jun, priced at S$227 found 4 days ago
Delta
Tue, 29 Apr - Tue, 6 May
ONT
Ontario
SEA
Seattle
S$264 Return, found 7 hours ago
S$264
Return
found 7 hours ago
Select Delta flight, departing Tue, 29 Apr from Ontario to Seattle, returning Tue, 6 May, priced at S$264 found 7 hours ago
Delta
Tue, 29 Apr - Sun, 4 May
ONT
Ontario
SEA
Seattle
S$278 Return, found 7 hours ago
S$278
Return
found 7 hours ago
Select Delta flight, departing Tue, 29 Apr from Ontario to Seattle, returning Sun, 4 May, priced at S$278 found 7 hours ago
Delta
Thu, 29 May - Tue, 10 Jun
ONT
Ontario
SEA
Seattle
S$281 Return, found 4 days ago
S$281
Return
found 4 days ago
Select Delta flight, departing Thu, 29 May from Ontario to Seattle, returning Tue, 10 Jun, priced at S$281 found 4 days ago
Delta
Thu, 29 May - Tue, 10 Jun
ONT
Ontario
SEA
Seattle
S$287 Return, found 4 days ago
S$287
Return
found 4 days ago
Select Delta flight, departing Thu, 29 May from Ontario to Seattle, returning Tue, 10 Jun, priced at S$287 found 4 days ago
Delta
Thu, 29 May - Tue, 10 Jun
ONT
Ontario
SEA
Seattle
S$294 Return, found 4 days ago
S$294
Return
found 4 days ago
Select Delta flight, departing Thu, 29 May from Ontario to Seattle, returning Tue, 10 Jun, priced at S$294 found 4 days ago
Delta
Thu, 24 Apr - Tue, 6 May
ONT
Ontario
SEA
Seattle
S$304 Return, found 7 hours ago
S$304
Return
found 7 hours ago
Select Delta flight, departing Thu, 24 Apr from Ontario to Seattle, returning Tue, 6 May, priced at S$304 found 7 hours ago
Delta
Tue, 29 Apr - Thu, 1 May
ONT
Ontario
SEA
Seattle
S$318 Return, found 7 hours ago
S$318
Return
found 7 hours ago
Select Delta flight, departing Tue, 29 Apr from Ontario to Seattle, returning Thu, 1 May, priced at S$318 found 7 hours ago
United
Thu, 29 May - Tue, 10 Jun
ONT
Ontario
SEA
Seattle
S$322 Return, found 4 days ago
S$322
Return
found 4 days ago
Select United flight, departing Thu, 29 May from Ontario to Seattle, returning Tue, 10 Jun, priced at S$322 found 4 days ago
American Airlines
Thu, 29 May - Tue, 10 Jun
ONT
Ontario
SEA
Seattle
S$355 Return, found 4 days ago
S$355
Return
found 4 days ago
Select American Airlines flight, departing Thu, 29 May from Ontario to Seattle, returning Tue, 10 Jun, priced at S$355 found 4 days ago
Ontario to Seattle route information
Origin airport
Los Angeles - Ontario Intl.
Destination airport
Seattle - Tacoma Intl.
Return price
S$226
Distance
1530 km

Perfect flights from Ontario to Seattle

Your Journey from Ontario to Seattle

Start your unforgettable journey with Expedia. Our broad selection of flights from Ontario to Seattle caters to every travel need. Whether you're yearning for a romantic escape, a solo adventure, or a cultural immersion, we've got you covered.
 

Choosing Your Ideal Flight

With Expedia, you have access to a wide range of airlines, including Delta, United, American Airlines. Our selection of flights from Los Angeles - Ontario Intl. to Seattle - Tacoma Intl. 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.
 

Maximizing Value with Ontario to Seattle Flights

Experience the joy of finding cheap flights from Los Angeles - Ontario Intl. to Seattle - Tacoma Intl. that fit your budget. Keep an eye out for our special deals and discounts, and check our flexible one-way fares from S$106 and roundtrip prices from S$227*.
 

Pre-Flight Essentials

Ensure a smooth journey from Ontario to Seattle with Expedia. From information about check-in times and in-flight amenities to guidance on baggage policies, we provide all the essentials to prepare you for your flight.
 

Experience the Vibrant Seattle

Picture yourself stepping off the plane in Seattle and immersing yourself in the unique atmosphere of Seattle. 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 Ontario to Seattle 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 Ontario to Seattle.
 

Beyond the Flight – Exploring Seattle

With Expedia, your adventure extends beyond the flight. Explore Seattle 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 Ontario to Seattle with Confidence

Planning your next great adventure is a breeze with Expedia. Our user-friendly platform, unbeatable prices, and round-the-clock customer support make your travel experience seamless and stress-free. Embark on your journey from Ontario to Seattle with confidence. Book your travel arrangements with Expedia today.
 
*Note: Prices may vary based on availability and are subject to change.

Frequently asked questions

How much is a flight from Ontario Airport to Sea-Tac Airport?
If you’re travelling between Ontario Airport and Seattle - Tacoma Intl. Airport (SEA), round-trip journeys start from S$227. This figure is based on fares quoted within the last 7 days on Expedia for flights departing within the next year, so don’t hang about. Book now and save yourself both money and time. Prices and availability are subject to change. Additional terms apply.
Do I need to pay a cancellation fee if I cancel my flight from Los Angeles - Ontario Intl. Airport (ONT) to Sea-Tac Airport?
We understand that things come up unexpectedly, so we’ve made it as simple as possible for you to cancel your trip online. Just visit the Customer Service Portal and follow the instructions.
How do I find cheap flights from Ontario Airport to Seattle - Tacoma Intl. Airport (SEA) 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 Los Angeles - Ontario Intl. Airport (ONT) to Seattle - Tacoma Intl. Airport (SEA) flights, you’ll see a “no change fees” filter for you to select.
How far is the flight from Los Angeles - Ontario Intl. Airport (ONT) to SEA?
The flight distance from Los Angeles - Ontario Intl. Airport (ONT) to Sea-Tac Airport is 1,550 kilometres. Pack yourself a drink, some snacks and an interesting novel to read. Keep yourself busy in the air and time will zip by.
Which airlines fly direct from Los Angeles - Ontario Intl. Airport (ONT) to Seattle - Tacoma Intl. Airport (SEA)?
Many travellers choose to fly with Alaska Airlines (AS) from Ontario Airport to Seattle - Tacoma Intl. Airport (SEA). This leading airline offers 117 flights monthly, so you can easily find a flight time that works for you. Another carrier operating on this route is Delta Air Lines (DL). You’ll have 86 flights every month to choose from.
Are Ontario Airport to Seattle - Tacoma Intl. Airport (SEA) flight tickets cheaper when they're purchased at the last minute?
Last-minute planners can sometimes pick up a bargain, with some super cheap airfares from ONT to Sea-Tac Airport popping up a few weeks prior to the departure date. If you’d rather book ahead of time, Expedia compares and updates all the best flight deals regularly — as early as a year in advance in some cases. It does depend on the carrier though, as not all airlines release prices so far in advance.

Explore a world of travel with Expedia

Seattle Airports

Seattle Paine Field Intl. Airport

Ontario Airports

Los Angeles

Los Angeles Intl. to Seattle
S$210.00

Orange County

John Wayne to Seattle
S$295.30

Burbank

Hollywood Burbank to Seattle
S$431.50
*Available to Expedia members.