How often are DEN to ONT flights on time?

Flights from Denver (DEN) to Ontario (ONT) arrive on time 78% of the time across 15,381 flights of official data.

Which airline is most reliable on the DEN to ONT route?

United Airlines has the best on-time record on this route at 82% across 4,377 flights.

Route reliability

Flights from Denver to Ontario arrive on time 78% of the time across 15,381 flights. Here’s how each airline really performs.

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On-time rate

15,381 flights

On-time = arrived within 15 minutes of schedule, per BTS TranStats. Compare the reverse leg ONT → DEN.

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Nonstop vs. Connecting Flights: The Reliability Trade-off

A stop multiplies the ways a trip can break. When it's worth it — and how to de-risk it.

Do Morning Flights Really Have Fewer Delays?

Yes — and there's a clear reason. How delays snowball through the day.

Are Some Airlines Really More Reliable Than Others?

The reliability gap between airlines is real — here's what actually drives it.

Score real DEN–ONT flights on reliability, weather, and connection safety — not just price.