How often are ONT to DEN flights on time?

Flights from Ontario (ONT) to Denver (DEN) arrive on time 89% of the time across 15,574 flights of official data.

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

United Airlines has the best on-time record on this route at 90% across 4,452 flights.

Route reliability

Flights from Ontario to Denver arrive on time 89% of the time across 15,574 flights. Here’s how each airline really performs.

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On-time rate

15,574 flights

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

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

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