Flight Reliability
UA 5231 · United Airlines
SBN → Chicago (SBN–ORD)
65
Usually Fine
WanderNerd Reliability Score
- 71%
- Arrive within 15 minutes
- 21 min
- Average arrival delay
- 1.9%
- Cancelled
- 1 min
- Median arrival delay
Based on 364 historical flights. Data through May 2026.
What the data says
Mondays have been rough.
UA 5231 arrived on time 82% of the time on Saturdays and just 58% on Mondays. That gap is worth planning around.
A bit ahead of the SBN–ORD route.
UA 5231 arrived on time 71% of the time, versus 66% across the SBN–ORD route.
Lagging the United Airlines network.
UA 5231 arrived on time 71% of the time, versus 79% across the United Airlines network.
Trending in the right direction.
UA 5231 arrived on time 73% of the time over the last three months in the data, compared with 58% in the three months before that.
The breakdown
- Mon58%(50 flights)
- Tue71%(51 flights)
- Wed82%(49 flights)
- Thu69%(52 flights)
- Fri71%(51 flights)
- Sat82%(51 flights)
- Sun65%(52 flights)
84%
May
Jun 80% → May 84% on time
| Month | On-time percentage | Flights |
|---|---|---|
| June 2025 | 80% | 30 |
| July 2025 | 74% | 31 |
| August 2025 | 80% | 30 |
| September 2025 | 83% | 30 |
| October 2025 | 77% | 31 |
| November 2025 | 64% | 28 |
| December 2025 | 53% | 30 |
| January 2026 | 60% | 30 |
| February 2026 | 59% | 27 |
| March 2026 | 68% | 28 |
| April 2026 | 67% | 30 |
| May 2026 | 84% | 31 |
- Departures on time
- 80%
- Diverted
- 0.3%
- Flights flown
- 356
- Months covered
- 12
Same route, other flights
Keep nerding
Based on 364 historical flights, because apparently we checked. Historical flight data: U.S. Bureau of Transportation Statistics, June 2025 – May 2026. Data through May 2026. How we calculate this.