How often are DEN to ONT flights on time?

Flights from Denver (DEN) to Ontario (ONT) arrive on time 78% of the time across 15,631 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 4,453 flights.

Route reliability

Flights from Denver to Ontario arrive on time 78% of the time across 15,631 flights. Here’s how each airline really performs.

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On-time rate

15,631 flights

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

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

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