65% of flights from Chicago to Decatur arrived on time over the past 12 months. That is worse than the typical U.S. route. The 7 a.m. departures ran on time 78% of the time; the 4 p.m. ones 55%. 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 ORD → DEC: when a flight was late, it was under 45 minutes late 46% of the time. About 1 in 7 flights landed an hour or more late, and 1 in 31 three hours or more; 4.5% were cancelled outright.
- On time or early65%
- 15–30 min late8.8%
- 30–60 min late7.3%
- 1–2 hours late6.7%
- 2–3 hours late4.0%
- 3+ hours late3.2%
- Diverted0.3%
- Cancelled4.5%
Share of all 627 scheduled flights, past 12 months, by arrival time against schedule.
By airline
| Airline | Flights | On time | Cancelled | Typical arrival | 1h+ late | Avg when late | Operated by |
|---|---|---|---|---|---|---|---|
| United Airlines | 627 | 65% | 4.5% | −4 min | 13.9% | +92 min | SkyWest |
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 ORD). Delays build through the day as late planes knock on, so early flights usually do best.
Last flight of the day
On ORD → DEC, each airline's last flight of the day was cancelled 6.5% of the time, against 1.9% for its earlier flights (3.4× as often). It arrived 3+ hours late 5.0% of the time (earlier flights: 2.3%). 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.
| Airline | Last departure | Last: cancelled | Last: 3h+ late | Earlier: cancelled | Next morning |
|---|---|---|---|---|---|
| United Airlines | 4:45 p.m. | 6.5% | 5.0% | 1.9% | first flight 7:45 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 DEC 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 (88%). Worst: August (62%).
By day of week
| Day | Flights | On time | Cancelled |
|---|---|---|---|
| Monday | 106 | 63% | 7.5% |
| Tuesday | 55 | — | — |
| Wednesday | 102 | 65% | 2.9% |
| Thursday | 101 | 69% | 4.0% |
| Friday | 104 | 76% | 2.9% |
| Saturday | 55 | — | — |
| Sunday | 104 | 61% | 3.9% |
Why flights were late
Share of delay minutes on flights 15+ minutes late, as reported to BTS by the airlines.
Cancellations: weather 23 · air traffic/airport 5
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.
| Flight | Departs | Flights | On time | Cancelled | Typical arrival | Operated by |
|---|---|---|---|---|---|---|
| UA 5064 | 4:45 p.m. | 158 | 53% | 7.6% | +11 min | SkyWest |
Nearby airport alternatives
Other ways to make the same trip, using airports within 60 miles of Chicago or Decatur. ORD → BMI has been 9 points more reliable.
| Route | Flights | On time | Cancelled |
|---|---|---|---|
| ORD → DEC (this route) | 627 | 65% | 4.5% |
| ORD → BMI Chicago O'Hare to Central Illinois at Bloomington-Normal | 879 | 74% | 3.9% |
| ORD → CMI Chicago O'Hare to University of Illinois Willard | 1,075 | 69% | 3.8% |
Questions
How often are flights from ORD to DEC on time?
65% of 627 scheduled flights from Chicago, IL to Decatur, IL arrived within 15 minutes of schedule between September 2025 and August 2026. 4.5% were cancelled.
What is the best time of day to fly ORD to DEC?
Flights scheduled to leave at 7 a.m. were the most reliable (78% on time). The 4 p.m. departures were the least (55%).
What month has the most delays from ORD to DEC?
August (62% on time). The best month is October (88%), over 2023–2026.
Is the last flight of the day from ORD to DEC more likely to be cancelled?
Yes. Each airline's last ORD–DEC flight of the day was cancelled 6.5% of the time over the past year, against 1.9% for its earlier flights. If the last flight is cancelled, the next one is usually the following morning.
Related
- DEC → ORD (return)
- Chicago O'Hare (ORD) delays by hour
- United Airlines on-time record
- Connecting off this flight? Check the risk
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.