Flying from Seattle, WA to Ontario can be expensive. Our search helps you compare cheap flights, airfare deals, and flight tickets across airlines and agencies so you can book at the best price.
We scan trusted travel agencies and airline booking systems for the route Seattle, WA - Ontario (SEA - ONT). We do not sell tickets or add fees - you choose where to buy.
Airfares vary by date, time, and airport. Use filters to find the best option by departure/arrival time, number of stops, airline or alliance, and booking channel.
If your dates are flexible, check the low-fare calendar to find the cheapest days. Booking round-trip in one order often reduces fees, and prices usually rise as departure approaches.
We also recommend you to look through the prices for return tickets from Ontario to Seattle, WA.
Airfares found by our users in the past 24 hours
The price for these dates could change. Use search to get the best price.
Average round-trip airfares from Seattle, WA to Ontario by months
| Month | Round-Trip |
|---|---|
| February 2026 | 11.02 - 15.02from 20 139र |
| March 2026 | 14.03 - 15.03from 10 536र |
| April 2026 | 17.04 - 01.05from 9 790र |
| May 2026 | find now |
| June 2026 | 27.06 - 04.07from 16 153र |
| July 2026 | 04.07 - 06.07from 16 885र |
| August 2026 | 08.08 - 10.08from 15 648र |
| September 2026 | find now |
| October 2026 | find now |
| November 2026 | find now |
| December 2026 | find now |
| January 2027 | find now |
Prices shown are based on searches from the last few days. Ticket prices can change and depend on availability at the time of booking.
Airlines are flying from Seattle, WA to Ontario
| Frontier Airlines | Alaska Airlines |
Popular flights from Seattle, WA
Frequently asked questions about flights from Seattle, WA to Ontario
How long does the flight from Seattle, WA to Ontario take?
Flight duration from Seattle, WA to Ontario varies by route, airline, and number of stops. Direct flights are faster; connecting flights may take longer. Use our search to compare options and see exact durations for your dates.
Are there direct flights from Seattle, WA to Ontario?
Availability of direct flights from Seattle, WA to Ontario depends on the route and season. Use our search and filter by "Direct" or "Non-stop" to see only direct options. We compare offers from many airlines and agencies.
Which airlines fly from Seattle, WA to Ontario?
Several airlines may operate flights from Seattle, WA to Ontario. On this page you can see airlines that serve this route. Our search compares prices across airlines and agencies so you can choose the best offer. We do not sell tickets; you book directly with the airline or agency.
What is the cheapest month to fly from Seattle, WA to Ontario?
Prices from Seattle, WA to Ontario vary by month and demand. On this page you can see average round-trip prices by month. Use the low-fare calendar and monthly table to find the cheapest dates. Booking in advance and avoiding peak seasons often helps get the best price.