On-time performance (OTP)

On-time performance measures how reliably a transportation or delivery operation hits its published or promised schedule, expressed as the percentage of trips or deliveries completed within an allowed margin of the scheduled time. Airlines, railways, transit systems, and delivery carriers all track it, though the specific definition of "on time" varies by industry and even by company.

The formula is on-time events / total events × 100, but the definition of "on-time" is a judgment call baked into the metric: airlines commonly count a flight as on time if it departs or arrives within 15 minutes of schedule, while a delivery carrier might use a much tighter or looser window. Because of this, on-time performance figures are only directly comparable between operators using the same threshold, and it is a narrower measure than on-time in full, which also checks that the full order or complete service was delivered, not just that it arrived within the time window.

Operators use on-time performance as a core reliability signal for customers and regulators, and to evaluate the effectiveness of route optimization and scheduling decisions. It is closely tied to cycle time and is often monitored alongside data from fleet telematics to diagnose where delays originate, whether at the origin, in transit, or at the destination, rather than treating a missed schedule as a single undifferentiated failure.