Champaign/Urbana, IL

What the Data Says About CMI

Champaign/Urbana, IL in Champaign/Urbana, Illinois handled 17,865 flights in the Bureau of Transportation Statistics dataset between 2020 and 2025, posting a 84.8% on-time departure rate. Of those flights, 2,707 experienced delays, 286 were cancelled, and 20 were diverted. The cancellation rate works out to 1.60%, the diversion rate to 0.11%, and the average delay when departures run late is 79.9 minutes. These figures are the baseline for comparing CMI against other airports in the same state and nationally.

Breaking down what drives delays at CMI, Late Aircraft leads the pack. Late Aircraft accounts for 37.8% of total delay minutes, followed by Carrier at 31.8% and NAS (National Aviation System) at 19.6%. Weather contributes 10.8% of delay minutes at this airport, while security holds the smallest share at 0.0%. Travelers often overestimate the weather share; the BTS categorization shows late-arriving aircraft and carrier operations as the larger contributors.

Seasonally, April runs the cleanest at CMI with a 95.2% on-time rate, while June is the roughest at 91.6% — a 4-point swing between best and worst month. Volume peaks in January, when average flights hit 276. The busiest route from CMI is to ORD (Chicago), with 4,377 flights at a 85.1% on-time rate. Combine these numbers — 84.8% on-time, 79.9-minute average delay, 1.60% cancellation rate — and you have a concrete picture of departure reliability at Champaign/Urbana, IL.