Houston (IAH) to San Juan (SJU): On-Time Performance
Data through July 2026
Houston (IAH) to San Juan (SJU) effectively runs on two schedules. In April 2026, 93% of arrivals were on time; in July 2024 that fell to 55% — a 39-point seasonal swing. Across the full period the route averages 81% on-time against a national 78%.
- On-time
- 81%
- arrived <15 min late
- Avg delay
- 13 min
- completed flights
- Cancelled
- 0.9%
- Flights/day
- 2.5
- last 12 months
- Duration
- 4h 29m
- scheduled
- Distance
- 2,007 mi
Best airline from IAH to SJU
2 airlines flew this route regularly between 2024-07 and 2026-07.
| Airline | On-time | Avg delay | Cancelled | Flights |
|---|---|---|---|---|
| United Airlinesmost reliable | 82% | 12 min | 0.7% | 1,771 |
| Spirit Airlines | 77% | 19 min | 2.3% | 300 |
Monthly on-time trend
Best time to fly from IAH to SJU
Aim for departures around 7 a.m. (88% on-time); avoid 1 p.m. departures (67%).
By day of week
| Day | On-time | Avg delay |
|---|---|---|
| Monday | 85% | 12 min |
| Tuesdaybest | 87% | 8 min |
| Wednesday | 84% | 10 min |
| Thursday | 82% | 11 min |
| Friday | 84% | 11 min |
| Saturday | 73% | 16 min |
| Sunday | 75% | 19 min |
What causes delays on this route
Share of total delay minutes by cause, as reported by carriers to the US DOT.
- Late-arriving aircraft31%
- Airline operations33%
- National airspace system25%
- Weather11%
Frequently asked questions
- How often are flights from IAH to SJU delayed?
- 19% of IAH–SJU flights arrived 15 or more minutes late (the US DOT definition of a delay) between 2024-07 and 2026-07. The average arrival delay across completed flights was 13 minutes.
- Which airline is most reliable from IAH to SJU?
- United Airlines has the best on-time record on this route at 82%, based on 1,771 flights. 2 airlines flew IAH–SJU frequently enough to compare in this period.
- What is the best time of day to fly from IAH to SJU?
- Departures around 7 a.m. have the best record (88% on-time), while departures around 1 p.m. have the worst (67%). As on most US routes, delays accumulate through the day, so earlier flights are generally safer.
- How long is the flight from IAH to SJU?
- The scheduled IAH–SJU flight time averages 4h 29m over 2,007 miles. Actual arrival times vary — flights on this route land 15+ minutes late 19% of the time.
- How often are IAH to SJU flights cancelled?
- 0.9% of scheduled flights on this route were cancelled between 2024-07 and 2026-07, at or below the national rate of 1.6%.
- What is the worst month to fly from IAH to SJU?
- July 2024 was the roughest month in this dataset, with only 55% of arrivals on time. The best was April 2026 at 93%. If your dates are flexible, that 39-point gap is worth planning around.
Explore related pages
More routes from IAH
Other ways to fly to San Juan (SJU)
Related guides
Based on 2,071 flights, 2024-07–2026-07. Source: US DOT Bureau of Transportation Statistics. Updated 2026-09-28.