￥10,890 Cheap Flights from Seattle (SEA) to Ontario (ONT)

View ￥10,890 flight on Tue, Jan 13, 2026Opens in a new window

Popular airlines from Seattle to Ontario, CA (ONT-Los Angeles - Ontario Intl.)

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Cheap Flights from Seattle to Ontario (SEA-ONT)

Prices were available within the past 7 days and start at ￥10,890 for one-way flights and ￥15,550 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Delta
Wed, Feb 4 - Wed, Feb 11
SEA
Seattle
ONT
Ontario
￥15,550 Roundtrip, found 3 days ago
￥15,550
Roundtrip
found 3 days ago
Select Delta flight, departing Wed, Feb 4 from Seattle to Ontario, returning Wed, Feb 11, priced at ￥15,550 found 3 days ago
Delta
Wed, Feb 4 - Wed, Feb 11
SEA
Seattle
ONT
Ontario
￥17,070 Roundtrip, found 3 days ago
￥17,070
Roundtrip
found 3 days ago
Select Delta flight, departing Wed, Feb 4 from Seattle to Ontario, returning Wed, Feb 11, priced at ￥17,070 found 3 days ago
Hawaiian Airlines
Thu, Jan 22 - Sun, Feb 8
SEA
Seattle
ONT
Ontario
￥18,540 Roundtrip, found 6 days ago
￥18,540
Roundtrip
found 6 days ago
Select Hawaiian Airlines flight, departing Thu, Jan 22 from Seattle to Ontario, returning Sun, Feb 8, priced at ￥18,540 found 6 days ago
Delta
Wed, Feb 4 - Wed, Feb 11
SEA
Seattle
ONT
Ontario
￥18,590 Roundtrip, found 3 days ago
￥18,590
Roundtrip
found 3 days ago
Select Delta flight, departing Wed, Feb 4 from Seattle to Ontario, returning Wed, Feb 11, priced at ￥18,590 found 3 days ago
Delta
Sat, Feb 7 - Sat, Feb 14
SEA
Seattle
ONT
Ontario
￥20,350 Roundtrip, found 1 day ago
￥20,350
Roundtrip
found 1 day ago
Select Delta flight, departing Sat, Feb 7 from Seattle to Ontario, returning Sat, Feb 14, priced at ￥20,350 found 1 day ago
Hawaiian Airlines
Thu, Feb 19 - Sun, Mar 8
SEA
Seattle
ONT
Ontario
￥21,660 Roundtrip, found 6 days ago
￥21,660
Roundtrip
found 6 days ago
Select Hawaiian Airlines flight, departing Thu, Feb 19 from Seattle to Ontario, returning Sun, Mar 8, priced at ￥21,660 found 6 days ago
Alaska Airlines
Wed, Feb 4 - Wed, Feb 11
SEA
Seattle
ONT
Ontario
￥21,680 Roundtrip, found 3 days ago
￥21,680
Roundtrip
found 3 days ago
Select Alaska Airlines flight, departing Wed, Feb 4 from Seattle to Ontario, returning Wed, Feb 11, priced at ￥21,680 found 3 days ago
Alaska Airlines
Wed, Feb 4 - Wed, Feb 11
SEA
Seattle
ONT
Ontario
￥21,800 Roundtrip, found 3 days ago
￥21,800
Roundtrip
found 3 days ago
Select Alaska Airlines flight, departing Wed, Feb 4 from Seattle to Ontario, returning Wed, Feb 11, priced at ￥21,800 found 3 days ago
United
Tue, May 12 - Wed, May 13
SEA
Seattle
ONT
Ontario
￥38,860 Roundtrip, found 16 hours ago
￥38,860
Roundtrip
found 16 hours ago
Select United flight, departing Tue, May 12 from Seattle to Ontario, returning Wed, May 13, priced at ￥38,860 found 16 hours ago
American Airlines
Tue, Jan 6 - Sat, Jan 10
SEA
Seattle
ONT
Ontario
￥61,810 Roundtrip, found 4 days ago
￥61,810
Roundtrip
found 4 days ago
Select American Airlines flight, departing Tue, Jan 6 from Seattle to Ontario, returning Sat, Jan 10, priced at ￥61,810 found 4 days ago

Find the cheapest month to fly from Seattle (SEA) to Ontario (ONT)

October is typically the cheapest month to fly

From ￥12,283 - ￥24,855 per traveler.

Alternative airports near Ontario

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

Select flight to John Wayne SNA. Cheapest option available. Average driving time to city center is 42 minutes. Flights from ￥58,770
SNA
John Wayne
Cheapest
Average driving time to city center42 min
Flights from ￥58,770
Flights from Seattle (SEA) to Ontario (ONT)
Origin airport
Seattle - Tacoma Intl.
Destination airport
Los Angeles - Ontario Intl.
Airlines serving
Alaska Airlines, American Airlines, Delta, Hawaiian Airlines, United
Roundtrip price
￥15,550
Distance
1530 km
Average flight time
2 hours 39 mins

Seattle to Ontario Flights

Sometimes you just need to get out of town or maybe you’re looking for a change of scenery. Regardless of the reason, a flight from Seattle to will do just the trick! Go on, plan to see all the famous landmarks and eat your weight in the local cuisine. Your trip is beckoning, so answer the call by packing your suitcase and filling your travel itinerary with exploring Ontario.

Whether you’re flying for business or jet-setting on your personal time, you’ve come to the right place. Here at Expedia.com, we’ll pair you up with SEA to ONT flights that won’t make your bank account wince. Ready to temporarily leave behind Seattle for new horizons? Browse through our cheap airfare, and filter by flight times and dates until you find just what you had in mind. From flights without layovers to ones that arrive early in the morning, you’ll come across plane tickets that suit your travel preferences. You can even bundle your flight to ONT with hotels and car rentals to score even bigger savings.

All set to hit the clouds? Book your travel arrangements with us today and have left-over money to put toward your travel outings and adventures.

Frequently asked questions

How much is a flight from Sea-Tac Airport to Ontario Airport?
Within the past 7 days on Expedia, for flights departing within the next year, the lowest price available for a round-trip flight from Sea-Tac Airport to Los Angeles - Ontario Intl. Airport (ONT) was ￥15,550. Fares this cheap don't hang around forever, so make sure you book yours today. 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-Tac Airport to ONT?
Most flights can be canceled online, but every airline has its own 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 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 Sea-Tac Airport to Los Angeles - Ontario Intl. Airport (ONT) flights, you'll see a "no change fees" filter for you to select.
How many hours is the flight from SEA to Los Angeles - Ontario Intl. Airport (ONT)?
It only takes roughly 2 hours and 36 minutes to fly from SEA to ONT. Recline your seat and make yourself comfortable — but not too comfortable. You'll be landing before long.
How far is the flight from Sea-Tac Airport to Ontario Airport?
It's around 1,550 kilometers from Sea-Tac Airport to Ontario Airport, so expect to be strapped into your seat for a while. Keep yourself occupied by packing things like playing cards (if you're traveling with friends) or the latest bestseller.
Which airlines fly direct from Sea-Tac Airport to ONT?
Alaska Airlines (AS) is a top option. It offers 121 flights between Seattle - Tacoma Intl. Airport (SEA) and ONT each month. Another airline servicing this route is Delta Air Lines (DL). You'll have 91 flights every month to select from.
Are Sea-Tac Airport to Los Angeles - Ontario Intl. Airport (ONT) flight tickets cheaper when they're purchased at the last minute?
Flight prices always go up and down, so it's no sure thing. While last-minute deals between Seattle - Tacoma Intl. Airport (SEA) and ONT are of course possible, it also makes sense to monitor prices well before you fly. In fact, some air carriers publish their prices up to 12 months prior to the departure date. Expedia is continuously updating the biggest airfare bargains around, so check back often and be ready to secure your seat when fare prices drop.

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