Best Time to Fly SJU to IAH: On-Time Stats by Hour & Airline
Luis Munoz Marin International → George Bush Intercontinental/Houston
Data through July 2026 · Last updated October 18, 2026
Over the last 12 months, 87.7% of San Juan (SJU) to Houston (IAH) flights arrived on time (930 scheduled flights). That is 10.0 points above the national average of 77.6%.
Among 2 airlines, United Airlines led with 88.9% on time and Spirit Airlines was last with 68.4%.
Over 24 months, Wednesday was the most reliable day (89% on time) and August the worst month (80%).
The cancellation rate was 0.5% (US average 1.8%).
SJU to IAH on-time performance by airline
Last 12 months. Airlines with fewer than 30 completed flights are marked “limited data”.
| Airline | On time | Avg delay when late | Cancelled | Flights |
|---|---|---|---|---|
| United Airlines | 88.9% | 55 min | 0.5% | 872 |
| Spirit Airlines | 68.4% | 74 min | 1.7% | 58 |
80%+ good 70–79.9% fair <70% poor
Best time of day to fly SJU to IAH
On-time arrival % by scheduled departure hour (local time), 1,972 flights over 24 months.
Show the numbers
| Departure hour | On time | Cancelled | Flights |
|---|---|---|---|
| 12am–1am | Limited data | 1 | |
| 2am–3am | 96.2% | 0.0% | 160 |
| 5am–6am | Limited data | 1 | |
| 6am–7am | 94.5% | 1.4% | 74 |
| 7am–8am | 94.9% | 0.9% | 635 |
| 8am–9am | Limited data | 4 | |
| 9am–10am | Limited data | 29 | |
| 10am–11am | 91.8% | 1.2% | 86 |
| 11am–12pm | 82.5% | 0.0% | 42 |
| 12pm–1pm | Limited data | 8 | |
| 1pm–2pm | Limited data | 17 | |
| 2pm–3pm | 76.8% | 0.4% | 559 |
| 3pm–4pm | 76.1% | 1.5% | 261 |
| 4pm–5pm | 71.0% | 3.1% | 32 |
| 5pm–6pm | Limited data | 4 | |
| 6pm–7pm | Limited data | 1 | |
| 8pm–9pm | 76.6% | 0.0% | 47 |
| 9pm–10pm | Limited data | 4 | |
| 10pm–11pm | Limited data | 7 | |
Best day of the week
24 months, by day of departure.
Best month to fly
24 months, by calendar month.
Holiday travel on SJU to IAH
On-time arrivals during holiday periods compared with all other days, last 24 months.
| Period | On time | vs other days | Cancelled | Flights |
|---|---|---|---|---|
| Thanksgiving week (Tue before to Mon after) | 69.4% | -15.6 pts | 0.0% | 36 |
| Christmas & New Year (Dec 20 - Jan 3) | 86.7% | +1.6 pts | 5.4% | 111 |
| Summer peak (Jun 15 - Aug 15) | 89.9% | +4.8 pts | 1.0% | 412 |
| All other days | 85.1% | — | 0.3% | 1,413 |
Monthly on-time trend
On-time arrival % each month, with the 12-month US average for reference.
What causes delays on this route
Share of reported delay minutes, last 12 months (BTS cause categories).