Direct flights from Seattle to Ontario SEA → ONT
Alaska Airlines, Delta Air Lines and Frontier Airlines fly nonstop from Seattle (SEA) to Ontario (ONT), several times daily. The flight takes about 2h 28m and covers 957 miles (1,540 km). Round-trip fares typically run around $277. Arrivals run on time 80.8% at SEA and 78.9% at ONT — BTS data for the last three months, counting arrivals within 15 minutes of schedule. Fares last checked 1 August 2026.
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Alaska Airlines
AS
ATI
8C
Delta Air Lines
DL
Frontier Airlines
F9
Frequently asked questions
Is there a direct flight from Seattle to Ontario?
Yes, Alaska Airlines, Delta Air Lines and 1 more airline operate nonstop flights from Seattle (SEA) to Ontario (ONT).
Which airlines fly direct from Seattle to Ontario?
Alaska Airlines, Delta Air Lines, Frontier Airlines operate nonstop flights from Seattle to Ontario.
How long is the flight from Seattle to Ontario?
The nonstop flight from Seattle to Ontario takes ~2h 28m (approximately 1540 km).
How often do direct flights operate from Seattle to Ontario?
Nonstop flights from Seattle to Ontario operate multiple daily.
What is the on-time performance for flights from Seattle to Ontario?
Arrivals run on time 80.8% at SEA and 78.9% at ONT — BTS data for the last three months, counting arrivals within 15 minutes of schedule.
How much is a round-trip flight from Seattle to Ontario?
Round-trip flights from Seattle (SEA) to Ontario (ONT) start at $277, with a typical fare around $277. Based on 1 recent fare combinations.
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