ON TIMEBOARD

CMI University of Illinois Willard delays

University of Illinois Willard Airport, Champaign/Urbana, IL. Every scheduled departure, September 2025 to August 2026.

On time
78%
departing flights, arrival < 15 min late
Left on time
79%
gate departure < 15 min late
Cancelled
3.1%
1,790 departures
Taxi out
14m
gate to wheels-up

78% of flights leaving Champaign (CMI) arrived on time over the past 12 months, 2 points better than the national average of 76%. About 5 flights leave CMI on a typical day; 3.1% were cancelled. 79% pushed back from the gate on time, so most of the lateness is already there when the flight leaves the gate.

At a glance

How late?

The on-time rate treats a flight 20 minutes late the same as one 5 hours late. Here's the split for flights leaving CMI: when a flight was late, it was under 45 minutes late 40% of the time. About 1 in 11 flights landed an hour or more late, and 1 in 53 three hours or more; 3.1% were cancelled outright.

Share of all 1,790 scheduled flights, past 12 months, by arrival time against schedule.

Best time of day to fly out of CMI

CMI is unusually consistent through the day. Flights scheduled to leave at 6 a.m. arrived on time 86% of the time; at 6 a.m. it was 86%, a 0-point gap. Taken together, early departures (5–9 a.m.) ran 87% on time against 64% for the evening bank (5–10 p.m.). Early planes usually start the day at the airport, so they haven't had a chance to pick up delays elsewhere. By evening a late inbound aircraft, a crew running out of duty hours or an afternoon thunderstorm can push one late flight into the next.

40%70%100%6 a.m. departures: 86% on time (427 flights)866a7 a.m. departures: 88% on time (249 flights)887a8 a.m. departures: too few flights8a9 a.m. departures: too few flights (47 flights)9a10 a.m. departures: too few flights10a11 a.m. departures: 77% on time (263 flights)7711anoon departures: too few flights (12 flights)12p1 p.m. departures: too few flights (32 flights)1p2 p.m. departures: 86% on time (217 flights)862p3 p.m. departures: 74% on time (237 flights)743p4 p.m. departures: too few flights (59 flights)4p5 p.m. departures: too few flights5p6 p.m. departures: 64% on time (162 flights)646p7 p.m. departures: too few flights (63 flights)7p8 p.m. departures: too few flights (22 flights)8p
CMI departures, share arriving on time, by scheduled local departure hour, past 12 months.
82%+ on time76–82%68–76%under 68%too few flights

Hour × month

Combine the two and the spread is wider still. The most reliable combination at CMI was a 6 a.m. departure in October (90% on time); the least, 6 a.m. in January (75%). If you can only move one thing, move the hour. Departure hour usually shifts the odds more than the month does.

Each cell: on-time rate for that departure hour in that calendar month, 2023–2026. Find your travel month, then look along the row for the greenest hour.

6a
Jan
75
Feb
87
Mar
86
Apr
·
May
83
Jun
·
Jul
·
Aug
82
Sep
77
Oct
90
Nov
87
Dec
82

Best and worst months

June is the hardest month at CMI, with 73% of flights on time across 2023–2026; September is the best at 85%. Summer (June–August) runs 7 points worse than autumn: heavy schedules, peak loads and afternoon thunderstorms. Winter costs 5 points against autumn. Cancellations peak in January (5.6% of flights).

40%70%100%Jan: 74% on time (392 flights)74JanFeb: 84% on time (372 flights)84FebMar: 78% on time (390 flights)78MarApr: 78% on time (439 flights)78AprMay: 75% on time (455 flights)75MayJun: 73% on time (401 flights)73JunJul: 79% on time (405 flights)79JulAug: 80% on time (447 flights)80AugSep: 85% on time (422 flights)85SepOct: 84% on time (458 flights)84OctNov: 84% on time (401 flights)84NovDec: 79% on time (402 flights)79Dec

Airlines at CMI

American Airlines runs 100% of departures from CMI, so CMI is effectively its hub. When American Airlines has a bad day, so does the airport.

AirlineDeparturesOn timeLeft on timeCancelledTypical arrival
American Airlines1,79078%79%3.1%−12 min

Why flights are late at CMI

Airlines report a cause for every flight that arrives 15 or more minutes late. At CMI, 38% of delay minutes came from late-arriving aircraft: the plane showed up late from its previous flight, so the delay started somewhere else. Next is the airlines themselves at 36%. That's why the first flight of the morning is the safest bet: it has no earlier flight to inherit a delay from. Of the 56 cancellations, 73% were blamed on weather.

Late inbound plane 38%Airline (crew, maintenance, ops) 36%Air traffic & airport (NAS) 22%Severe weather 4%

The average taxi from gate to takeoff is 14 minutes, shorter than at most large U.S. airports.

CMI vs nearby airports

AirportDistanceDeparturesOn timeCancelled
CMI University of Illinois Willard—1,79078%3.1%
BMI Central Illinois at Bloomington-Normal45 mi2,77580%2.0%

Month by month

Over the latest 12 months 78% of CMI departures were on time, against 80% in the 12 months before, a decline of 2 points. The best recent month was September 2025 (86%); the worst, December 2025 (69%).

50%75%100%Sep 2023Jan 2024Jan 2025Jan 2026Sep 2023: 86% on time, 0.0% cancelledOct 2023: 81% on time, 0.0% cancelledNov 2023: 90% on time, 0.0% cancelledDec 2023: 91% on time, 0.0% cancelledJan 2024: 63% on time, 13.0% cancelledFeb 2024: 91% on time, 0.0% cancelledMar 2024: 83% on time, 0.0% cancelledApr 2024: 83% on time, 0.7% cancelledMay 2024: 64% on time, 2.6% cancelledJun 2024: 75% on time, 0.0% cancelledJul 2024: 78% on time, 0.8% cancelledAug 2024: 83% on time, 0.0% cancelledSep 2024: 82% on time, 0.0% cancelledOct 2024: 95% on time, 0.0% cancelledNov 2024: 88% on time, 0.9% cancelledDec 2024: 80% on time, 0.0% cancelledJan 2025: 83% on time, 1.7% cancelledFeb 2025: 78% on time, 3.3% cancelledMar 2025: 76% on time, 0.8% cancelledApr 2025: 73% on time, 2.1% cancelledMay 2025: 81% on time, 0.0% cancelledJun 2025: 71% on time, 1.5% cancelledJul 2025: 75% on time, 3.0% cancelledAug 2025: 77% on time, 2.1% cancelledSep 2025: 86% on time, 0.8% cancelledOct 2025: 76% on time, 0.0% cancelledNov 2025: 75% on time, 8.0% cancelledDec 2025: 69% on time, 5.7% cancelledJan 2026: 78% on time, 2.7% cancelledFeb 2026: 85% on time, 0.0% cancelledMar 2026: 77% on time, 3.4% cancelledApr 2026: 77% on time, 4.1% cancelledMay 2026: 79% on time, 2.0% cancelledJun 2026: 73% on time, 4.1% cancelledJul 2026: 82% on time, 2.0% cancelledAug 2026: 79% on time, 4.0% cancelled
Share of flights on time, by month (hover a point for cancellations)

Last flights of the day

The last flight of the day is a different bet. Across routes from CMI, each airline's final departure was cancelled 5.2% of the time, against 1.8% for its earlier flights (2.9× as often). Late in the day crews run short on duty hours, aircraft arrive late from elsewhere, and with no later flight to fold passengers into, cancelling is easier for the airline. 1.6% of last flights landed 3+ hours late. The riskiest last flight out was American Airlines to Chicago (8.1% cancelled).

Last flight toAirlineLeavesCancelled3h+ lateOn time
ORD ChicagoAmerican Airlines6:36 p.m.8.1%1.7%60%
DFW DallasAmerican Airlines2:46 p.m.2.3%1.4%82%

Each airline's last scheduled departure of the day on a route, on days it flies the route at least twice; past 12 months. Riskiest first.

Tips for flying out of CMI

Routes from CMI

Least reliable first. Routes with at least 365 flights a year.

ToFlightsOn timeCancelledTypical arrival
ORD Chicago1,07573%3.8%−7 min
DFW Dallas71585%2.1%−18 min

Flights into CMI

Arriving rather than leaving? These are the routes into University of Illinois Willard, least reliable first. The weakest is from Chicago (69% on time).

FromFlightsOn timeCancelled
ORD Chicago1,07569%3.8%
DFW Dallas71583%1.8%

Questions about CMI delays

What is the best time to fly out of CMI?

Flights scheduled at 6 a.m.: over the past year 86% of CMI departures at that hour arrived on time, against 86% at 6 a.m., the worst hour.

What month has the most flight delays at CMI?

June (73% on time). September is the best month (85%).

Why are flights delayed at CMI?

The biggest cause was late-arriving aircraft (38% of delay minutes): the plane showed up late from its previous flight, so the delay started somewhere else. Then the airlines themselves (36%).

How often are flights cancelled at CMI?

3.1% of scheduled departures over the past 12 months, peaking in January at 5.6%.

Hours are scheduled local departure times. "On time" means arriving less than 15 minutes late at the destination; cancelled and diverted flights count as not on time. Method.