Cheap Flights from Seattle (SEA) to Ontario (ONO)

Popular airlines from Seattle-Tacoma International Airport (SEA) to Ontario, OR (ONO-Ontario Municipal)

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Flights from Seattle (SEA) to Ontario (ONO)
Origin airport
Seattle - Tacoma Intl.
Destination airport
Ontario Municipal
Distance
342 mi

Seattle to Ontario Flights

The cheapest times to fly from Seattle to Ontario

On average, Thursday can be the cheapest time to fly, according to data from the Airlines Reporting Corporation (ARC), one of the world's biggest databases for global airline sales. The data reveals that you could save up to 16% by flying on a Thursday—the cheapest day to travel on average—instead of a Sunday—the most expensive. Some of the most affordable flights from Seattle to Ontario are during the month of . You can find some of the cheapest flights from Seattle to Ontario with Expedia's search tool and vast selection of airlines.

 

The best time to book a flight from Seattle to Ontario

Sunday is one of the best days to book for cheap flights from Seattle to Ontario: Tickets reserved on a Sunday cost between 6% and 13% less than those reserved on a Friday, according to ARC data. The data also suggests booking early can also lead to cheaper airfares. You could save 24% by buying your tickets for domestic flights at least a month in advance and 10% by booking international flights 2 months in advance.

 

How to find cheap round-trip tickets from Seattle to Ontario

Being flexible with your dates and using Expedia's Price Drop Protection and Price Tracking features are some of the best ways of finding a cheap ticket from Seattle to Ontario in 2026. You can also book with separate airlines for your outbound and return journeys, from one-way. Expedia also offers Price Drop Protection, so if the cost of your airfare goes down after booking, you'll receive a credit for the difference*. This is available for a small fee, and is free to One Key Gold and Platinum tier members.

 

Expedia's Price Tracking feature means you can stay on top of airfares without manually checking every day. It sends you automated price alerts for cheap Seattle to Ontario flights and uses historical data to indicate when the best time to book is. Download Expedia's free app to activate this handy tool in a few easy taps.

 

You could also save big by booking one of Expedia's vacation packages. Bundling together your Seattle to Ontario airfare with your accommodations and car rental is often cheaper than booking everything separately. There’s also One Key, Expedia's generous rewards program. Join for free and you could earn One Key cash on most bookings to save on future adventures.

 

*Terms apply.

 

Disclaimer: ARC The statistics are based on average round-trip ticket prices between January and August 2023. The percentages you see are averages.

 

Frequently asked questions

How much does a flight from Seattle - Tacoma Intl. Airport (SEA) to Ontario, OR (ONO-Ontario Municipal) cost?
Secure a cheap one-way flight or cheap return flight from Seattle - Tacoma Intl. Airport (SEA) to Ontario, OR (ONO-Ontario Municipal) with Expedia. Enter your travel dates and sort by "Price (lowest to highest)" to see our cheapest flight deals on this route.
What is the cheapest month to fly from Seattle - Tacoma Intl. Airport (SEA) to Ontario, OR (ONO-Ontario Municipal)?
The cheapest month to fly from SEA to ONO is , when there's less demand. Off-peak season is typically when you'll find cheap fares for travel between these airports.
What is the cheapest airline that flies from Seattle - Tacoma Intl. Airport (SEA) to Ontario, OR (ONO-Ontario Municipal)?
Use the filter tool on Expedia to compare airlines and find the most affordable carrier that'll take you from SEA to ONO. Then, sort your results by "Price (lowest to highest)" to score the best deal available.
How many flights per day from Seattle - Tacoma Intl. Airport (SEA) to Ontario, OR (ONO-Ontario Municipal)?
You'll have to catch a flight with a layover when traveling from Seattle - Tacoma Intl. Airport (SEA) to Ontario, OR (ONO-Ontario Municipal). There are no daily direct flights on this route. However, just filter your search to include one or two stops to find the best option for your trip.
What day of the week has the most flights from SEA to ONO?
Usually you'll find the widest variety of flight choices on a Friday. Tuesdays tend to be the quietest.* However, this can change based on the airline, time of year and other factors.*Busiest/quietest day to travel is based on Expedia flight demand through January to December 2024.
What is the best time to fly from Seattle - Tacoma Intl. Airport (SEA) to Ontario, OR (ONO-Ontario Municipal)?
To avoid possible delays on the Seattle - Tacoma Intl. Airport (SEA) to Ontario, OR (ONO-Ontario Municipal) route, aim to travel before 3 PM. Departures after this time have a 22% higher chance of cancellation.**Most reliable time of the day and month to travel recommendation is based on January through August 2024 flight status data sourced from OAG's global flight data platform.
What airports do you fly into for Ontario from Seattle - Tacoma Intl. Airport (SEA)?
If you've booked a direct flight from Seattle - Tacoma Intl. Airport (SEA) to Ontario, Boise Airport (BOI) is the only airport you can land at.
Is it cheaper to buy a plane ticket from Seattle - Tacoma Intl. Airport (SEA) to Ontario, OR (ONO-Ontario Municipal) last-minute?
Booking your ticket from SEA to ONO just before your getaway is generally more expensive. But if you're flexible with your travel times and dates, you could snag a cheap last-minute fare.
Is it cheaper to book a SEA to ONO flight and hotel package?
Compared with arranging hotels and flights separately, booking a SEA to ONO flight and hotel package with Expedia could lead to significant savings. What's more, managing everything in one place will take the hassle out of planning your trip. Simply secure your flights and choose from our wide range of stays, then tailor your trip with other add-ons like tours, activities and car rentals.
Can I cancel or change the date of my flight from Seattle - Tacoma Intl. Airport (SEA) to Ontario, OR (ONO-Ontario Municipal)?
If you booked your SEA to ONO flight in the last 24 hours, you may be able to modify or cancel it without fees. Depending on the airline and the fare type you purchased, additional charges may apply for changes beyond this timeframe. Airline policies and contact information can be found in your itinerary or confirmation email. Or, go to our Customer Service portal for further details.

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