San Jose, CA

What the Data Says About SJC

San Jose, CA in San Jose, California handled 546,547 flights in the Bureau of Transportation Statistics dataset between 2020 and 2025, posting a 84.2% on-time departure rate. Of those flights, 86,586 experienced delays, 5,418 were cancelled, and 423 were diverted. The cancellation rate works out to 0.99%, the diversion rate to 0.08%, and the average delay when departures run late is 59.8 minutes. These figures are the baseline for comparing SJC against other airports in the same state and nationally.

Breaking down what drives delays at SJC, Late Aircraft leads the pack. Late Aircraft accounts for 46.2% of total delay minutes, followed by Carrier at 34.8% and NAS (National Aviation System) at 16.4%. Weather contributes 2.4% of delay minutes at this airport, while security holds the smallest share at 0.2%. Travelers often overestimate the weather share; the BTS categorization shows late-arriving aircraft and carrier operations as the larger contributors.

Seasonally, February runs the cleanest at SJC with a 94.2% on-time rate, while June is the roughest at 90% — a 4-point swing between best and worst month. Volume peaks in July, when average flights hit 8,143. The busiest route from SJC is to SAN (San Diego), with 31,755 flights at a 82.2% on-time rate. Combine these numbers — 84.2% on-time, 59.8-minute average delay, 0.99% cancellation rate — and you have a concrete picture of departure reliability at San Jose, CA.