Birmingham, AL

What the Data Says About BHM

Birmingham, AL in Birmingham, Alabama handled 178,467 flights in the Bureau of Transportation Statistics dataset between 2020 and 2025, posting a 81.5% on-time departure rate. Of those flights, 33,077 experienced delays, 2,031 were cancelled, and 238 were diverted. The cancellation rate works out to 1.14%, the diversion rate to 0.13%, and the average delay when departures run late is 73.9 minutes. These figures are the baseline for comparing BHM against other airports in the same state and nationally.

Breaking down what drives delays at BHM, Late Aircraft leads the pack. Late Aircraft accounts for 43.9% of total delay minutes, followed by Carrier at 32.3% and NAS (National Aviation System) at 16.5%. Weather contributes 7.1% 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, November runs the cleanest at BHM with a 93.9% on-time rate, while July is the roughest at 88.5% — a 5-point swing between best and worst month. Volume peaks in October, when average flights hit 2,697. The busiest route from BHM is to BHM (Birmingham), with 16,520 flights at a 86.4% on-time rate. Combine these numbers — 81.5% on-time, 73.9-minute average delay, 1.14% cancellation rate — and you have a concrete picture of departure reliability at Birmingham, AL.