SFO to IAH flight delays
SFO IAH San Francisco to George Bush · 1,635 miles
10,033 flights were scheduled from SFO to IAH over July 2023 through June 2026. Of the 9,911 that made the trip, 84.5% reached the gate less than 15 minutes behind schedule. These are arrival figures: “on time” means the flight reached the gate less than 15 minutes behind schedule. Arrivals are what decide whether you make the connection, so route and airline pages are scored on them rather than on pushback.
Data through June 2026 · Bureau of Transportation Statistics
The route in brief
- Flights in the window
- 10,033
- Arrived on time
- 84.5%
- Cancelled
- 0.9%
- Scheduled distance
- 1,635 miles
Cancellations are counted against everything scheduled. Diverted flights are counted with them rather than as very late arrivals, which is why the on-time share and the cancellation rate do not add up to everything that happened.
Airline by airline
Airlines with at least 100 flights on SFO–IAH, busiest first. Same route, same weather, same air traffic — which makes this the fairest comparison on the site.
| Airline | Arrived on time | Typical delay | Cancelled | Flights |
|---|---|---|---|---|
| United Airlines | 84.5% | 58 min | 0.9% | 10,033 |
Month by month
July was the month to avoid on SFO–IAH: 77.8% of flights arrived on time, against 90.5% in September. Each bar pools three years of that calendar month.
| Month | Share flights that arrived on time | Flights |
|---|---|---|
| January | 83.2% | 792 |
| February | 88.6% | 736 |
| March | 85.9% | 842 |
| April | 89.3% | 831 |
| May | 82.6% | 867 |
| June | 81.3% | 866 |
| July | 77.8% | 858 |
| August | 82.1% | 858 |
| September | 90.5% | 823 |
| October | 89.7% | 862 |
| November | 84.1% | 826 |
| December | 79.7% | 872 |
Both ends of the route
A route’s record is built out of two airports’ habits. The hour-by-hour grid for each is on its own page.
SFO to IAH in one number
SFO → IAH
When a flight on this route was late, it was late by about 58 min.
Questions about SFO to IAH
- How often do SFO to IAH flights arrive on time?
- 84.5% of the time, across the 9,911 flights that actually made the trip, July 2023 through June 2026. No single airline flew enough of them to be rated separately.
- What is the worst month to fly SFO to IAH?
- July, at 77.8% of arrivals on time, with 858 flights scheduled. September was the best of the year at 90.5%.
- How late are SFO–IAH flights when they are late?
- 58 min on average, counting only the flights that arrived 15 minutes or more behind schedule. The on-time flights are left out of that average on purpose — mixing them in would flatter it.
- How often is the SFO to IAH flight cancelled?
- 0.9% of scheduled flights on this route were cancelled, July 2023 through June 2026. Diverted flights are counted with the cancellations rather than as late arrivals.
- Are these departure or arrival numbers?
- Arrival. A flight counts as on time here if it reached the gate at IAH less than 15 minutes behind schedule. Airport pages score departures instead, because that is the number you can act on when you pick a booking time.