IAH to SAT flight delays & on-time performance
Nonstop flights from George Bush Intercontinental Airport to San Antonio International Airport · 191 miles · Aug 2025 – Jul 2026
No FAA-reported ground stops or delays at IAH or SAT right now. Individual flights can still be delayed by the airline; check with your airline for your flight.
Key facts
- Flights from Houston (IAH) to San Antonio (SAT) arrived on time 83% of the time in Aug 2025 – Jul 2026, better than the 78% national average.
- 0.4% were cancelled, and 6% arrived an hour or more late.
- Departures scheduled around 7am did best (94% on time); around 6pm did worst (73%).
- Tuesday was the most reliable day to fly (86% on time) and Monday the least (79%).
- The largest source of delay minutes was late-arriving aircraft (45%).
Which airline is most on time from IAH to SAT?
Ranked by on-time arrival rate. Regional airlines fly under their partner's brand (e.g. SkyWest for Delta Connection or United Express).
| Airline | On time | Cancelled | Avg delay | 1 hr+ late | Flights |
|---|---|---|---|---|---|
| United Airlines | 83% | 0.4% | 11 min | 5.4% | 2,302 |
| SkyWest AirlinesRegional airline operating flights for United Express, Delta Connection, American Eagle and Alaska. | 82% | 1.0% | 14 min | 9.7% | 104 |
Best time of day to fly
On-time arrival rate by scheduled departure hour (local time).
- 7am94%337 flights
- 9am86%248 flights
- 11am93%107 flights
- 12pm85%180 flights
- 2pm83%353 flights
- 4pm83%192 flights
- 6pm73%365 flights
- 7pm76%37 flights
- 8pm76%327 flights
- 9pm80%258 flights
Best day of the week
On-time arrival rate by day of departure.
- Monday79%1.4% cancelled
- Tuesday86%0.0% cancelled
- Wednesday84%0.3% cancelled
- Thursday82%0.0% cancelled
- Friday81%0.3% cancelled
- Saturday84%0.3% cancelled
- Sunday81%0.6% cancelled
On-time trend by month
Why flights are late
Share of delay minutes by cause, as reported by airlines to the DOT.
- Late-arriving aircraft45%
- Airline (crew, maintenance, cleaning, fueling)35%
- Air traffic control & airport congestion14%
- Extreme weather7%
- Security0%
Why flights are cancelled
Share of cancellations by reason.
- Extreme weather60%
- Airline (crew, maintenance, cleaning, fueling)20%
- Air traffic control & airport congestion20%
- Security0%
IAH to SAT: common questions
- How often are IAH to SAT flights on time?
- 83% of flights arrived less than 15 minutes late in Aug 2025 – Jul 2026, compared with 78% for all US flights.
- How often are flights from Houston to San Antonio cancelled?
- 0.4% of scheduled flights were cancelled (10 of 2,406).
- How long are typical delays?
- Across all flights the average arrival delay was 11 min (early arrivals count as zero). Flights that were late arrived 59 min behind schedule on average, and 5.6% of flights were an hour or more late.
- How long is taxi time at IAH?
- Flights on this route spent 21 min taxiing from the gate to takeoff on average.
Related routes
Return trip: SAT to IAH — 82% on time
More flights from Houston
Data: U.S. DOT Bureau of Transportation Statistics, Aug 2025 – Jul 2026 (12 months). Latest month published by BTS: July 2026. Route: IAH → SAT, nonstop flights by US airlines that report to the DOT. How we calculate this.