Direct flights from Ontario to Seattle
- ~5 flights a day
- 3 airlines
🔔 Track this route
We check ONT → SEA every day and email you the cheapest nonstop fares we find.
Free · one-click unsubscribe
When the nonstops leave
Typical weekly schedule · 36 flights per week (~5 per day) · Updated 21d ago
Most leave in the afternoon.
Arrive the same day
6:02 AM
8:30 AMTue
Arrive the same day
12:12 PM
3:14 PM
5:17 PMMon, Fri
5:44 PM
Arrive the same day
7:59 PM5 days a week
Alaska Airlines
Departs Terminal 2
Frontier Airlines
Departs Terminal 2
Frequently asked questions
Is there a direct flight from Ontario to Seattle?
Yes. Alaska Airlines, Delta Air Lines and Frontier Airlines fly nonstop from Ontario (ONT) to Seattle (SEA), several times daily. The flight takes about 2h 28m and covers 957 miles (1,540 km). Schedule data from 27 September 2026.
Which airlines fly direct from Ontario to Seattle?
Alaska Airlines, Delta Air Lines, Frontier Airlines operate nonstop flights from Ontario to Seattle.
How long is the flight from Ontario to Seattle?
The nonstop flight from Ontario to Seattle takes ~2h 28m (approximately 1540 km).
How often do direct flights operate from Ontario to Seattle?
Nonstop flights from Ontario to Seattle operate several times daily — 36 flights per week (~5 per day).
What days of the week are there direct flights from Ontario to Seattle?
Direct flights from Ontario to Seattle operate every day of the week. Alaska Airlines flies daily and Frontier Airlines flies daily.