Best time to fly out of Champaign (CMI)
The early-flight folk wisdom holds up at University of Illinois Willard: departures in the 6–8am band left on time 88.4% of the time, against 79% in the 2–4pm band. These are historical odds, not forecasts. The records say what happened on this schedule over three years; they know nothing about tomorrow’s thunderstorm.
Data through June 2026 · Bureau of Transportation Statistics
On-time rate by hour and day
On this page, “on time” means a departure that pushed back less than 15 minutes behind its scheduled time — the Bureau of Transportation Statistics definition, and the one airlines are held to.
| Departure time | Mon | Tue | Wed | Thu | Fri | Sat | Sun |
|---|---|---|---|---|---|---|---|
| Before 6am | – | – | – | – | – | – | – |
| 6–8am | 89 | 90 | 89 | 91 | 87 | 89 | 85 |
| 8–10am | – | – | – | – | – | – | – |
| 10am–12pm | – | – | – | – | – | – | – |
| 12–2pm | – | – | – | – | – | – | – |
| 2–4pm | 77 | 79 | 82 | 81 | 77 | 80 | 79 |
| 4–6pm | – | – | – | – | – | – | – |
| 6–8pm | – | – | – | – | – | – | – |
| 8–10pm | – | – | – | – | – | – | – |
| 10pm–12am | – | – | – | – | – | – | – |
The steadiest stretch at CMI was 6–8am — 88.4% of departures left on time across 1,910 flights. The weakest was 2–4pm at 79%.
The year at CMI
June was the hard month at CMI: 76.6% of departures left on time, across 393 flights. October was the easy one at 87.5%. Each month pools three years of that month, so a single bad week does not decide it.
| Month | Share departures that left on time | Flights |
|---|---|---|
| January | 81.6% | 386 |
| February | 86.5% | 360 |
| March | 81.1% | 386 |
| April | 83.4% | 408 |
| May | 80.7% | 425 |
| June | 76.6% | 393 |
| July | 80.3% | 378 |
| August | 85% | 390 |
| September | 86.6% | 338 |
| October | 87.5% | 400 |
| November | 87.4% | 369 |
| December | 79.6% | 371 |
Airlines at CMI
Every airline with at least 100 departures from CMI, busiest first. These are that airline’s departures from this airport only — its record across the country sits on its own page.
| Airline | Left on time | Typical delay | Cancelled | Departures |
|---|---|---|---|---|
| Envoy Air | 83% | 99 min | 2% | 4,604 |
What delays out of CMI were put down to
Airlines file a reason with every arrival running 15 minutes late or more. Across 850 flights that departed CMI and ran 15 minutes late or more, the delay minutes break down with 43.8% put down to late-arriving aircraft and 29.5% to airline operations.
- Late-arriving aircraft 43.8%
- Airline operations 29.5%
- Air traffic & airport volume 18.9%
- Severe weather 7.9%
- Security 0%
Late-arriving aircraft is the knock-on category: the plane came in late, so it went out late again. It is why a 7am problem in Newark is still a problem in Denver at dinnertime, and why it is usually the biggest slice on the bar.
If you are connecting through CMI
Of 4,603 scheduled arrivals into CMI, 75.3% reached the gate less than 15 minutes behind schedule. Of the 1,030 arrivals that ran late, 51.7% were no more than 45 minutes behind — which is the difference between a tight connection and a new boarding pass.
Work out a specific layover — pick the airport and the minutes you have, and the tool reads the same arrival records back as a share.
Busiest routes out of CMI
Ranked by flights, with the share that arrived on time at the far end. Where a route carries enough flights for a page of its own the chip goes there; otherwise it goes to the destination airport.
CMI in one number
University of Illinois Willard (CMI)
Rank 214 of 363 US airports by departures. Steadiest stretch of the day: 6–8am. Hardest month: June.
Questions about CMI
- What is the best time of day to fly out of University of Illinois Willard?
- 6–8am. Departures in that band left on time 88.4% of the time across 1,910 flights, July 2023 through June 2026 — the best of the ten bands in the day. The 2–4pm band was the weakest at 79%.
- What is the worst month to fly out of CMI?
- June: 76.6% of the departures that flew left on time, with 393 scheduled. October was the other end of the year at 87.5%. Each figure pools three years of that calendar month.
- How often are flights cancelled at CMI?
- 2% of scheduled departures were cancelled over July 2023 through June 2026. Cancellations are counted against everything scheduled, not against everything that flew — a rate that looks small still adds up to real people in a rebooking line.