RM976 Cheap Flights from Ontario Intl. Airport (ONT) to Seattle (SEA)

View RM976 flight on Wed, 27 May 2026Opens in a new window

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

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

Prices were available within the past 7 days and start at RM976 for one-way flights and RM1,952 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Delta
Wed, 27 May - Fri, 29 May
ONT
Ontario
SEA
Seattle
RM1,952 Return, found 3 days ago
RM1,952
Return
found 3 days ago
Select Delta flight, departing Wed, 27 May from Ontario to Seattle, returning Fri, 29 May, priced at RM1,952 found 3 days ago
Delta
Wed, 27 May - Fri, 29 May
ONT
Ontario
SEA
Seattle
RM1,991 Return, found 3 days ago
RM1,991
Return
found 3 days ago
Select Delta flight, departing Wed, 27 May from Ontario to Seattle, returning Fri, 29 May, priced at RM1,991 found 3 days ago
Delta
Wed, 27 May - Fri, 29 May
ONT
Ontario
SEA
Seattle
RM2,030 Return, found 3 days ago
RM2,030
Return
found 3 days ago
Select Delta flight, departing Wed, 27 May from Ontario to Seattle, returning Fri, 29 May, priced at RM2,030 found 3 days ago
United
Wed, 27 May - Fri, 29 May
ONT
Ontario
SEA
Seattle
RM2,031 Return, found 3 days ago
RM2,031
Return
found 3 days ago
Select United flight, departing Wed, 27 May from Ontario to Seattle, returning Fri, 29 May, priced at RM2,031 found 3 days ago
United
Wed, 27 May - Fri, 29 May
ONT
Ontario
SEA
Seattle
RM2,070 Return, found 3 days ago
RM2,070
Return
found 3 days ago
Select United flight, departing Wed, 27 May from Ontario to Seattle, returning Fri, 29 May, priced at RM2,070 found 3 days ago
United
Wed, 27 May - Fri, 29 May
ONT
Ontario
SEA
Seattle
RM2,110 Return, found 3 days ago
RM2,110
Return
found 3 days ago
Select United flight, departing Wed, 27 May from Ontario to Seattle, returning Fri, 29 May, priced at RM2,110 found 3 days ago
Delta
Wed, 27 May - Fri, 29 May
ONT
Ontario
SEA
Seattle
RM2,149 Return, found 3 days ago
RM2,149
Return
found 3 days ago
Select Delta flight, departing Wed, 27 May from Ontario to Seattle, returning Fri, 29 May, priced at RM2,149 found 3 days ago
American Airlines
Wed, 27 May - Fri, 29 May
ONT
Ontario
SEA
Seattle
RM2,153 Return, found 3 days ago
RM2,153
Return
found 3 days ago
Select American Airlines flight, departing Wed, 27 May from Ontario to Seattle, returning Fri, 29 May, priced at RM2,153 found 3 days ago
Delta
Wed, 27 May - Fri, 29 May
ONT
Ontario
SEA
Seattle
RM2,189 Return, found 3 days ago
RM2,189
Return
found 3 days ago
Select Delta flight, departing Wed, 27 May from Ontario to Seattle, returning Fri, 29 May, priced at RM2,189 found 3 days ago
American Airlines
Wed, 27 May - Fri, 29 May
ONT
Ontario
SEA
Seattle
RM2,384 Return, found 3 days ago
RM2,384
Return
found 3 days ago
Select American Airlines flight, departing Wed, 27 May from Ontario to Seattle, returning Fri, 29 May, priced at RM2,384 found 3 days ago
United
Wed, 27 May - Fri, 29 May
ONT
Ontario
SEA
Seattle
RM2,428 Return, found 3 days ago
RM2,428
Return
found 3 days ago
Select United flight, departing Wed, 27 May from Ontario to Seattle, returning Fri, 29 May, priced at RM2,428 found 3 days ago
United
Wed, 27 May - Fri, 29 May
ONT
Ontario
SEA
Seattle
RM2,467 Return, found 3 days ago
RM2,467
Return
found 3 days ago
Select United flight, departing Wed, 27 May from Ontario to Seattle, returning Fri, 29 May, priced at RM2,467 found 3 days ago
United
Wed, 27 May - Fri, 29 May
ONT
Ontario
SEA
Seattle
RM2,506 Return, found 3 days ago
RM2,506
Return
found 3 days ago
Select United flight, departing Wed, 27 May from Ontario to Seattle, returning Fri, 29 May, priced at RM2,506 found 3 days ago

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 RM1,952. 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.

Travel information

Origin airport
Ontario Intl. Airport
Destination airport
Seattle - Tacoma Intl.
Return price
RM1,952
Distance
1530 km
Average flight time
3 hours 9 mins

Book with confidence

Perfect flights from Ontario Intl. Airport to Seattle

Your Journey from Ontario Intl. Airport to Seattle

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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 Ontario Intl. Airport 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 Intl. Airport to Seattle Flights

Experience the joy of finding cheap flights from Ontario Intl. Airport 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 RM976 and roundtrip prices from RM1,952*.
 

Pre-Flight Essentials

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Experience the Vibrant Seattle

Picture yourself stepping off the plane in Seattle 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 Ontario Intl. Airport 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 Intl. Airport 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 Intl. Airport 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 Intl. Airport to Seattle with confidence. Book your travel arrangements with Expedia today.
 
*Note: Prices may vary based on availability and are subject to change.
Perfect flights from Ontario Intl. Airport to Seattle

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