฿6,525 Cheap Flights from Ontario Intl. Airport (ONT) to Seattle (SEA)

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

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

Prices were available within the past 7 days and start at ฿6,525 for one-way flights and ฿12,550 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Delta
Tue, 30 Jun - Sat, 4 Jul
ONT
Ontario
SEA
Seattle
฿12,550 Return, found 5 days ago
฿12,550
Return
found 5 days ago
Select Delta flight, departing Tue, 30 Jun from Ontario to Seattle, returning Sat, 4 Jul, priced at ฿12,550 found 5 days ago
Delta
Tue, 30 Jun - Sat, 4 Jul
ONT
Ontario
SEA
Seattle
฿13,245 Return, found 5 days ago
฿13,245
Return
found 5 days ago
Select Delta flight, departing Tue, 30 Jun from Ontario to Seattle, returning Sat, 4 Jul, priced at ฿13,245 found 5 days ago
Delta
Tue, 30 Jun - Sat, 4 Jul
ONT
Ontario
SEA
Seattle
฿13,730 Return, found 5 days ago
฿13,730
Return
found 5 days ago
Select Delta flight, departing Tue, 30 Jun from Ontario to Seattle, returning Sat, 4 Jul, priced at ฿13,730 found 5 days ago
Delta
Tue, 30 Jun - Sat, 4 Jul
ONT
Ontario
SEA
Seattle
฿14,425 Return, found 5 days ago
฿14,425
Return
found 5 days ago
Select Delta flight, departing Tue, 30 Jun from Ontario to Seattle, returning Sat, 4 Jul, priced at ฿14,425 found 5 days ago
United
Tue, 30 Jun - Sat, 4 Jul
ONT
Ontario
SEA
Seattle
฿15,180 Return, found 5 days ago
฿15,180
Return
found 5 days ago
Select United flight, departing Tue, 30 Jun from Ontario to Seattle, returning Sat, 4 Jul, priced at ฿15,180 found 5 days ago
United
Tue, 30 Jun - Sat, 4 Jul
ONT
Ontario
SEA
Seattle
฿15,505 Return, found 5 days ago
฿15,505
Return
found 5 days ago
Select United flight, departing Tue, 30 Jun from Ontario to Seattle, returning Sat, 4 Jul, priced at ฿15,505 found 5 days ago
American Airlines
Tue, 30 Jun - Sat, 4 Jul
ONT
Ontario
SEA
Seattle
฿15,545 Return, found 5 days ago
฿15,545
Return
found 5 days ago
Select American Airlines flight, departing Tue, 30 Jun from Ontario to Seattle, returning Sat, 4 Jul, priced at ฿15,545 found 5 days ago
United
Tue, 30 Jun - Sat, 4 Jul
ONT
Ontario
SEA
Seattle
฿15,830 Return, found 5 days ago
฿15,830
Return
found 5 days ago
Select United flight, departing Tue, 30 Jun from Ontario to Seattle, returning Sat, 4 Jul, priced at ฿15,830 found 5 days ago
American Airlines
Tue, 30 Jun - Sat, 4 Jul
ONT
Ontario
SEA
Seattle
฿15,835 Return, found 5 days ago
฿15,835
Return
found 5 days ago
Select American Airlines flight, departing Tue, 30 Jun from Ontario to Seattle, returning Sat, 4 Jul, priced at ฿15,835 found 5 days ago
American Airlines
Tue, 30 Jun - Sat, 4 Jul
ONT
Ontario
SEA
Seattle
฿15,870 Return, found 5 days ago
฿15,870
Return
found 5 days ago
Select American Airlines flight, departing Tue, 30 Jun from Ontario to Seattle, returning Sat, 4 Jul, priced at ฿15,870 found 5 days ago

Alternative airports near Seattle

Prices were available within the past 7 days. Prices and availability are subject to change.

Select flight to Seattle - Tacoma Intl. SEA. Cheapest option available. Average driving time to city centre is 20 minutes. Flights from ฿12,550
SEA
Seattle - Tacoma Intl.
Cheapest
Average driving time to city centre20 min
Flights from ฿12,550

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 ฿12,550. 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
฿12,550
Distance
1530 km
Average flight time
2 hours 54 mins

Book with confidence

Perfect flights from Ontario Intl. Airport to Seattle

Embark on an unforgettable journey without breaking the bank with Expedia's incredible deals on cheap flights from Ontario Intl. Airport to Seattle. Whether you're aching for a romantic escape with your partner, craving an adventurous solo expedition, or yearning to immerse yourself in the local history and culture, we've got you covered.
 
Picture yourself strolling through the streets of , surrounded by breathtaking architecture and absorbing the vibrant atmosphere of this captivating city. Indulge in the mouth-watering local specialties, from tantalizing street food to exquisite fine dining. With Expedia, you can experience all of this and more, without sacrificing your budget.
 
Our flexible Ontario Intl. Airport to Seattle - Tacoma Intl. ticket options cater to your travel preferences, with incredible one-way fares from ฿6,525 and roundtrip prices from ฿12,550. Whether you're planning a short city break or a longer adventure, our dynamic pricing ensures that you find the best deals for your journey.
 
But the magic doesn't stop there. Expedia offers a range of partner services to enhance your trip. Rent a car at Seattle - Tacoma Intl. and explore and its surrounding areas at your own pace. Discover hidden gems off the beaten path, and create unforgettable memories. We also provide a handpicked selection of accommodations, from charming bed and breakfasts to luxury hotels, ensuring that you have a comfortable and memorable stay.
 
Planning your next great adventure is a breeze with Expedia. Our user-friendly platform, unbeatable prices, and round-the-clock customer support are designed to make your travel experience seamless and stress-free. So, why wait? Book your to travel arrangements today and embark on the journey of a lifetime in Seattle.
Perfect flights from Ontario Intl. Airport to Seattle
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