74% of flights from Boise to Chicago arrived on time over the past 12 months. That is worse than the typical U.S. route. The 8 a.m. departures ran on time 83% of the time; the 1 p.m. ones 62%. Most reliable airline: United Airlines (79%). 12% 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 BOI → ORD: when a flight was late, it was under 45 minutes late 47% of the time. About 1 in 10 flights landed an hour or more late, and 1 in 34 three hours or more; 1.2% were cancelled outright.
- On time or early74%
- 15–30 min late8.3%
- 30–60 min late6.1%
- 1–2 hours late5.1%
- 2–3 hours late2.2%
- 3+ hours late3.0%
- Diverted0.5%
- Cancelled1.2%
Share of all 1,111 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 | 733 | 79% | 1.6% | −6 min | 7.1% | +79 min | SkyWest 67%, United Airlines 33% |
| American Airlines | 378 | 63% | 0.3% | −2 min | 16.4% | +109 min | American Airlines 55%, Envoy 40%, SkyWest 5% |
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 BOI). Delays build through the day as late planes knock on, so early flights usually do best.
By airline and hour
| Departs | United Airlines | American Airlines |
|---|---|---|
| 8 a.m. | 83% | — |
| noon | 75% | — |
| 1 p.m. | — | 62% |
| 3 p.m. | — | 65% |
Last flight of the day
On BOI → ORD, each airline's last flight of the day was cancelled 1.1% of the time, against 2.3% for its earlier flights, so here the last flight is actually the safer one. It arrived 3+ hours late 2.9% of the time (earlier flights: 1.6%). 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 | 12:30 p.m. | 1.1% | 3.0% | 2.2% | first flight 8:25 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.
By month
Each calendar month pooled over 2023–2026. Best: February (88%). Worst: July (72%).
By day of week
| Day | Flights | On time | Cancelled |
|---|---|---|---|
| Monday | 162 | 70% | 0.6% |
| Tuesday | 159 | 80% | 1.3% |
| Wednesday | 157 | 76% | 0.6% |
| Thursday | 158 | 73% | 1.3% |
| Friday | 157 | 66% | 0.6% |
| Saturday | 158 | 79% | 1.9% |
| Sunday | 160 | 72% | 1.9% |
Why flights were late
Share of delay minutes on flights 15+ minutes late, as reported to BTS by the airlines.
Cancellations: weather 12 · airline 1
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 5386 | 8:20 a.m. | 313 | 81% | 2.6% | −7 min | SkyWest |
Worst days in the past year
| Date | Flights | On time | Cancelled |
|---|---|---|---|
| Aug 30, 2026 | 3 | 0% | 0 |
| Apr 2, 2026 | 3 | 0% | 1 |
| Jul 17, 2026 | 3 | 0% | 0 |
| Mar 31, 2026 | 3 | 0% | 0 |
| Aug 13, 2026 | 3 | 0% | 0 |
Questions
How often are flights from BOI to ORD on time?
74% of 1,111 scheduled flights from Boise, ID to Chicago, IL arrived within 15 minutes of schedule between September 2025 and August 2026. 1.2% were cancelled.
What is the best time of day to fly BOI to ORD?
Flights scheduled to leave at 8 a.m. were the most reliable (83% on time). The 1 p.m. departures were the least (62%).
Which airline is most on time from BOI to ORD?
United Airlines: 79% of its 733 flights on the route arrived on time. American Airlines: 63%.
What month has the most delays from BOI to ORD?
July (72% on time). The best month is February (88%), over 2023–2026.
Is the last flight of the day from BOI to ORD more likely to be cancelled?
No, the opposite. Each airline's last BOI–ORD flight of the day was cancelled 1.1% 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
- ORD → BOI (return)
- Boise /Gowen (BOI) delays by hour
- Flights into Chicago O'Hare (ORD)
- United Airlines on-time record
- American 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.