What counts as a flight delay?

The DOT defines a flight as "delayed" when it arrives at the gate 15 or more minutes after its scheduled arrival time. This is the standard used in all official BTS on-time statistics and the metric airlines report to the government.

Important nuance: the clock starts and stops at the gate, not when the plane lands on the runway. A flight that lands on time but sits on the taxiway for 20 minutes waiting for a gate is counted as delayed. Conversely, a flight that departs 10 minutes late but makes up time in the air and arrives within 14 minutes of schedule is counted as on-time.

Airlines know this metric matters and build "schedule padding" into their published flight times — padding the scheduled duration by 15-30 minutes beyond the actual flying time. This is why a flight from ORD to LAX might be scheduled for 4 hours 25 minutes when the actual air time is 3 hours 50 minutes. It's not deception; it's airlines giving themselves buffer to hit the 15-minute on-time window. For you as a traveler, the 15-minute DOT standard is what matters for delay compensation claims and on-time statistics.