ON TIMEBOARD

DEC → ORD on time

Decatur (Decatur, IL) to Chicago O'Hare (Chicago, IL). Every scheduled flight, September 2025 to August 2026.

On time
63%
arrived < 15 min late
Cancelled
5.4%
627 flights
Typical arrival
+1 min
median vs schedule
When late
+101 min
average delay
Flights / day
2
1 airline

63% of flights from Decatur to Chicago arrived on time over the past 12 months. That is worse than the typical U.S. route. The 9 a.m. departures ran on time 77% of the time; the 6 p.m. ones 52%. 19% of flights arrived more than an hour late or not at all.

How late?

The on-time rate treats a flight 20 minutes late the same as one 5 hours late. Here's the split for DEC → ORD: when a flight was late, it was under 45 minutes late 44% of the time. About 1 in 7 flights landed an hour or more late, and 1 in 23 three hours or more; 5.4% were cancelled outright.

Share of all 627 scheduled flights, past 12 months, by arrival time against schedule.

By airline

AirlineFlightsOn timeCancelledTypical arrival1h+ lateAvg when lateOperated by
United Airlines62763%5.4%+1 min13.9%+101 minSkyWest

Airline = the name on the ticket. Regional flights (e.g. "Delta Connection") count under the ticketing airline, and the operator is listed.

Best time of day to fly

On-time rate by scheduled departure hour (local time at DEC). Delays build through the day as late planes knock on, so early flights usually do best.

40%70%100%9 a.m. departures: 77% on time (281 flights)779a10 a.m. departures: too few flights10a11 a.m. departures: too few flights11anoon departures: too few flights12p1 p.m. departures: too few flights1p2 p.m. departures: too few flights2p3 p.m. departures: too few flights3p4 p.m. departures: too few flights4p5 p.m. departures: too few flights5p6 p.m. departures: 52% on time (110 flights)526p7 p.m. departures: 53% on time (233 flights)537p
DEC → ORD, share of flights arriving on time, by departure hour. Hours with under 100 flights are greyed out.
82%+ on time76–82%68–76%under 68%too few flights

Last flight of the day

On DEC → ORD, each airline's last flight of the day was cancelled 8.0% of the time, against 2.3% for its earlier flights (3.5× as often). It arrived 3+ hours late 4.2% of the time (earlier flights: 3.4%). It matters more than the numbers suggest. Miss an earlier flight and there's another one that evening; miss the last one and you're usually waiting until morning.

AirlineLast departureLast: cancelledLast: 3h+ lateEarlier: cancelledNext morning
United Airlines6:45 p.m.8.0%4.2%2.3%first flight 9:37 a.m.

Last flight = the airline's last scheduled departure on this route that day, on days it flies the route at least twice; past 12 months. Times are typical scheduled times over the latest three months.

If you need to be in ORD tonight, book an earlier flight so there's a backup if it's cancelled.

By month

Each calendar month pooled over 2023–2026. Best: October (79%). Worst: January (65%).

40%70%100%Jan: 65% on time (159 flights)65JanFeb: 79% on time (146 flights)79FebMar: 72% on time (159 flights)72MarApr: 77% on time (154 flights)77AprMay: 68% on time (160 flights)68MayJun: 66% on time (155 flights)66JunJul: 67% on time (160 flights)67JulAug: 69% on time (159 flights)69AugSep: 77% on time (154 flights)77SepOct: 79% on time (160 flights)79OctNov: 78% on time (153 flights)78NovDec: 70% on time (159 flights)70Dec

By day of week

DayFlightsOn timeCancelled
Monday10673%7.5%
Tuesday55——
Wednesday10265%2.9%
Thursday10164%5.0%
Friday10464%3.9%
Saturday55——
Sunday10458%6.7%

Why flights were late

Share of delay minutes on flights 15+ minutes late, as reported to BTS by the airlines.

Late inbound plane 40%Airline (crew, maintenance, ops) 35%Air traffic & airport (NAS) 17%Severe weather 8%

Cancellations: weather 26 · air traffic/airport 8

Month by month

Not enough months with data to draw a trend.

Flight numbers on this route

Regular flights with at least 120 scheduled trips in the past year. Sorted by departure time.

FlightDepartsFlightsOn timeCancelledTypical arrivalOperated by
UA 50279:37 a.m.26577%2.3%−6 minSkyWest
UA 50647:09 p.m.23752%7.2%+8 minSkyWest

Nearby airport alternatives

Other ways to make the same trip, using airports within 60 miles of Decatur or Chicago. BMI → ORD has been 16 points more reliable.

RouteFlightsOn timeCancelled
DEC → ORD (this route)62763%5.4%
BMI → ORD Central Illinois at Bloomington-Normal to Chicago O'Hare87979%3.5%
CMI → ORD University of Illinois Willard to Chicago O'Hare1,07573%3.8%

Questions

How often are flights from DEC to ORD on time?

63% of 627 scheduled flights from Decatur, IL to Chicago, IL arrived within 15 minutes of schedule between September 2025 and August 2026. 5.4% were cancelled.

What is the best time of day to fly DEC to ORD?

Flights scheduled to leave at 9 a.m. were the most reliable (77% on time). The 6 p.m. departures were the least (52%).

What month has the most delays from DEC to ORD?

January (65% on time). The best month is October (79%), over 2023–2026.

Is the last flight of the day from DEC to ORD more likely to be cancelled?

Yes. Each airline's last DEC–ORD flight of the day was cancelled 8.0% of the time over the past year, against 2.3% for its earlier flights. If the last flight is cancelled, the next one is usually the following morning.

Related

Domestic flights by the airlines that report to the U.S. DOT, plus their regional partners. "On time" means arriving less than 15 minutes after schedule; cancelled and diverted flights count as not on time. Past performance is a guide, not a forecast. Method.