IAH to SFO flight delays & on-time performance
Nonstop flights from George Bush Intercontinental Airport to San Francisco International Airport · 1,635 miles · Aug 2025 – Jul 2026
No FAA-reported ground stops or delays at IAH or SFO 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 Francisco (SFO) arrived on time 78% of the time in Aug 2025 – Jul 2026, in line with the national average.
- 0.5% were cancelled, and 7% arrived an hour or more late.
- United Airlines is the only airline reporting nonstop flights on this route.
- Departures scheduled around 5am did best (98% on time); around 7pm did worst (55%).
- Tuesday was the most reliable day to fly (85% on time) and Monday the least (71%).
- The largest source of delay minutes was air traffic control & airport congestion (46%).
Which airline is most on time from IAH to SFO?
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 | 78% | 0.5% | 15 min | 7.3% | 3,598 |
Best time of day to fly
On-time arrival rate by scheduled departure hour (local time).
- 5am98%364 flights
- 7am88%365 flights
- 8am72%125 flights
- 9am74%204 flights
- 10am72%161 flights
- 12pm79%360 flights
- 2pm85%275 flights
- 3pm75%289 flights
- 4pm77%294 flights
- 5pm86%71 flights
- 6pm65%358 flights
- 7pm55%116 flights
- 8pm64%246 flights
- 9pm82%350 flights
Best day of the week
On-time arrival rate by day of departure.
- Monday71%0.2% cancelled
- Tuesday85%0.4% cancelled
- Wednesday80%0.6% cancelled
- Thursday73%0.4% cancelled
- Friday76%0.2% cancelled
- Saturday82%0.8% cancelled
- Sunday79%0.8% cancelled
On-time trend by month
Why flights are late
Share of delay minutes by cause, as reported by airlines to the DOT.
- Air traffic control & airport congestion46%
- Late-arriving aircraft26%
- Airline (crew, maintenance, cleaning, fueling)24%
- Extreme weather3%
- Security0%
Why flights are cancelled
Share of cancellations by reason.
- Airline (crew, maintenance, cleaning, fueling)65%
- Extreme weather35%
- Air traffic control & airport congestion0%
- Security0%
IAH to SFO: common questions
- How often are IAH to SFO flights on time?
- 78% 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 Francisco cancelled?
- 0.5% of scheduled flights were cancelled (17 of 3,598).
- How long are typical delays?
- Across all flights the average arrival delay was 15 min (early arrivals count as zero). Flights that were late arrived 63 min behind schedule on average, and 7.3% of flights were an hour or more late.
- How long is taxi time at IAH?
- Flights on this route spent 22 min taxiing from the gate to takeoff on average.
Related routes
Return trip: SFO to IAH — 84% 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 → SFO, nonstop flights by US airlines that report to the DOT. How we calculate this.