Flight Reliability
UA 1644 · United Airlines
San Juan → Houston (SJU–IAH)
98
Nerd Approved
WanderNerd Reliability Score
- 94%
- Arrive within 15 minutes
- 14 min early
- Average arrival delay
- 0.8%
- Cancelled
- 19 min early
- Median arrival delay
Based on 364 historical flights. Data through May 2026.
What the data says
Saturday is the weak spot.
UA 1644 arrived on time 98% of the time on Mondays. On Saturdays: 90%.
A bit ahead of the SJU–IAH route.
UA 1644 arrived on time 94% of the time, versus 88% across the SJU–IAH route.
Well ahead of the United Airlines network.
UA 1644 arrived on time 94% of the time, versus 79% across the United Airlines network.
Ticking up lately.
UA 1644 arrived on time 98% of the time over the last three months in the data, compared with 94% in the three months before that.
The breakdown
- Mon98%(49 flights)
- Tue96%(52 flights)
- Wed98%(51 flights)
- Thu90%(52 flights)
- Fri94%(52 flights)
- Sat90%(51 flights)
- Sun94%(53 flights)
100%
May
Jun 90% → May 100% on time
| Month | On-time percentage | Flights |
|---|---|---|
| June 2025 | 90% | 29 |
| July 2025 | 87% | 31 |
| August 2025 | 87% | 30 |
| September 2025 | 100% | 30 |
| October 2025 | 100% | 31 |
| November 2025 | 93% | 30 |
| December 2025 | 90% | 31 |
| January 2026 | 100% | 30 |
| February 2026 | 92% | 26 |
| March 2026 | 94% | 31 |
| April 2026 | 100% | 30 |
| May 2026 | 100% | 31 |
- Departures on time
- 93%
- Diverted
- 0.3%
- Flights flown
- 360
- 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.