Flight Reliability
DL 2231 · Delta Air Lines
Chicago → Salt Lake City (ORD–SLC)
77
Usually Fine
WanderNerd Reliability Score
- 78%
- Arrive within 15 minutes
- 19 min
- Average arrival delay
- 1.1%
- Cancelled
- 1 min early
- Median arrival delay
Based on 365 historical flights. Data through May 2026.
What the data says
Skip Monday if you can.
DL 2231 arrived on time 81% of the time on Thursdays. On Mondays: 73%.
Better than the ORD–SLC route average.
DL 2231 arrived on time 78% of the time, versus 70% across the ORD–SLC route.
A bit behind the Delta Air Lines network.
DL 2231 arrived on time 78% of the time, versus 81% across the Delta Air Lines network.
Ticking up lately.
DL 2231 arrived on time 78% of the time over the last three months in the data, compared with 74% in the three months before that.
The breakdown
- Mon73%(51 flights)
- Tue79%(52 flights)
- Wed75%(52 flights)
- Thu81%(52 flights)
- Fri81%(52 flights)
- Sat80%(51 flights)
- Sun77%(51 flights)
84%
May
Jun 70% → May 84% on time
| Month | On-time percentage | Flights |
|---|---|---|
| June 2025 | 70% | 30 |
| July 2025 | 81% | 31 |
| August 2025 | 74% | 31 |
| September 2025 | 90% | 30 |
| October 2025 | 90% | 31 |
| November 2025 | 73% | 30 |
| December 2025 | 60% | 30 |
| January 2026 | 81% | 31 |
| February 2026 | 81% | 26 |
| March 2026 | 67% | 30 |
| April 2026 | 83% | 30 |
| May 2026 | 84% | 31 |
- Departures on time
- 84%
- Diverted
- 0%
- Flights flown
- 361
- Months covered
- 12
Same route, other flights
Keep nerding
Based on 365 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.