Boise, ID

What the Data Says About BOI

Boise, ID in Boise, Idaho handled 266,753 flights in the Bureau of Transportation Statistics dataset between 2020 and 2025, posting a 85.2% on-time departure rate. Of those flights, 39,406 experienced delays, 1,457 were cancelled, and 257 were diverted. The cancellation rate works out to 0.55%, the diversion rate to 0.10%, and the average delay when departures run late is 69.4 minutes. These figures are the baseline for comparing BOI against other airports in the same state and nationally.

Breaking down what drives delays at BOI, Carrier leads the pack. Carrier accounts for 41.3% of total delay minutes, followed by Late Aircraft at 33.3% and NAS (National Aviation System) at 19.1%. Weather contributes 6.1% 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, October runs the cleanest at BOI with a 94.8% on-time rate, while December is the roughest at 91.5% — a 3-point swing between best and worst month. Volume peaks in August, when average flights hit 4,046. The busiest route from BOI is to BOI (Boise), with 25,171 flights at a 86% on-time rate. Combine these numbers — 85.2% on-time, 69.4-minute average delay, 0.55% cancellation rate — and you have a concrete picture of departure reliability at Boise, ID.