Route Reliability

Route reliability

San Francisco (SFO) to Houston (IAH): which airline is most on time?

On-time arrivals, cancellations and long delays for every airline that reported nonstop flights from San Francisco, CA (SFO) to Houston, TX (IAH), September 2025 to August 2026.

Historical performance Official DOT data through August 2026 · Not live flight status

San Francisco, CAHouston, TX

Check a route

Three-letter airport codes, nonstop U.S. domestic flights. One direction at a time.

Route at a glance · September 2025 to August 2026

SFO to IAH

San Francisco, CA to Houston, TX

On time
83.6%vs 75.6% U.S. average Better than average
Cancelled
0.3%vs 1.9% U.S. average Better than average
60+ min late
3.5%vs 8.1% U.S. average Better than average
Scheduled flights
3,578in 12 months1 airline
Only rated airline
United Airlines83.6% on time · 3,578 flights

On time more often than the U.S. average, with fewer cancellations.

Compared with all U.S. flights, September 2025 to August 2026. “About average” means within 1.5 points for on time, 0.3 for cancelled and 1 for 60+ minutes late.

Airlines on this route

Ranked by on-time arrival

Airlines from SFO to IAH, September 2025 to August 2026. Rates are shares of all scheduled flights.
Airline On time Cancelled 60+ min late Avg delay when late Diverted Flights
1. United Airlines 83.6% 0.3% 3.5% 50 min 0.2% 3,578

On time = arrived within 15 minutes of schedule. Avg delay when late = average arrival delay of flights 15+ minutes late. "Most reliable" needs at least 300 flights in 12 months. Tap a heading to sort.

What this means

How SFO to IAH compares.

  • United Airlines was the only airline with enough flights on this route to rate (3,578 flights). 83.6% of them arrived within 15 minutes of schedule.
  • 0.3% of flights on this route were cancelled, 1.6 points lower than the U.S. average of 1.9%.
  • 3.5% of flights, about 1 in 29, arrived an hour or more late. When a flight was late (15+ minutes), the average arrival delay was 50 min.
  • Overall, 83.6% of flights on this route arrived on time, 8.0 points higher than the U.S. average of 75.6%.
  • Over the last 3 years, September was the most reliable month on this route (90.4% on time) and July the least reliable (76.6%).
  • Cancellations peaked in January, when 5.6% of flights were cancelled.
  • Flights scheduled to depart 7 am to 8 am were the most punctual (95.3% on time); flights scheduled to depart 10 am to 11 am were the least (63.0%).
  • In the other direction, Houston (IAH) to San Francisco (SFO), 77.8% of flights were on time and 0.4% were cancelled. Compare airlines IAH to SFO.

Best and worst months to fly SFO to IAH

Jan 78.3%
Feb 88.3%
Mar 85.5%
Apr 89.0%
May 81.9%
Jun 79.8%
Jul 76.6%
Aug 79.1%
Sep 90.4%
Oct 89.3%
Nov 83.8%
Dec 79.5%
Share of scheduled flights on time 12-month average 83.6%
All airlines combined, by calendar month, September 2023 to August 2026 (3 years pooled). Scale starts at zero.
Show as table
PeriodOn timeFlights
January 78.3% 792
February 88.3% 736
March 85.5% 842
April 89.0% 831
May 81.9% 867
June 79.8% 866
July 76.6% 875
August 79.1% 858
September 90.4% 823
October 89.3% 862
November 83.8% 826
December 79.5% 872

Month by month, last 12 months

Sep 92.4%
Oct 89.5%
Nov 80.3%
Dec 83.9%
Jan 84.8%
Feb 87.0%
Mar 86.5%
Apr 88.0%
May 78.5%
Jun 81.7%
Jul 76.4%
Aug 74.2%
Share of scheduled flights on time U.S. average 75.6%
All airlines combined, September 2025 to August 2026. Scale starts at zero.
Show as table
PeriodOn timeFlights
Sep 2025 92.4% 289
Oct 2025 89.5% 306
Nov 2025 80.3% 299
Dec 2025 83.9% 311
Jan 2026 84.8% 303
Feb 2026 87.0% 277
Mar 2026 86.5% 310
Apr 2026 88.0% 300
May 2026 78.5% 307
Jun 2026 81.7% 300
Jul 2026 76.4% 297
Aug 2026 74.2% 279

Best and worst departure times

<6a 91.2%
7a 95.3%
8a 86.8%
9a 86.5%
10a 63.0%
11a 69.5%
12p 75.0%
1p 81.1%
2p 77.8%
3p Insufficient sample
4p 81.6%
5p Insufficient sample
6p 84.8%
7p 89.0%
10p Insufficient sample
11p 82.5%
Share of scheduled flights on time
By scheduled local departure hour at SFO, September 2025 to August 2026. Hours with no scheduled flights are omitted. Scale starts at zero.
Show as table
PeriodOn timeFlights
Departing before 6 am 91.2% 702
Departing 7 am to 8 am 95.3% 365
Departing 8 am to 9 am 86.8% 121
Departing 9 am to 10 am 86.5% 244
Departing 10 am to 11 am 63.0% 211
Departing 11 am to noon 69.5% 154
Departing noon to 1 pm 75.0% 180
Departing 1 pm to 2 pm 81.1% 185
Departing 2 pm to 3 pm 77.8% 361
Departing 3 pm to 4 pm Insufficient sample 5
Departing 4 pm to 5 pm 81.6% 343
Departing 5 pm to 6 pm Insufficient sample 21
Departing 6 pm to 7 pm 84.8% 145
Departing 7 pm to 8 pm 89.0% 173
Departing 10 pm to 11 pm Insufficient sample 3
Departing 11 pm to midnight 82.5% 365
Woman at an airport window watching a plane take off
Photo: Depositphotos (licensed stock, illustrative only). Credits

Sources & data dates

Source
U.S. DOT Bureau of Transportation Statistics, Reporting Carrier On-Time Performance (1987-present)
Period
September 2025 to August 2026 (12 months); month-of-year patterns September 2023 to August 2026
Data through
August 2026
Processed
2026-11-03
Scope
Nonstop scheduled flights from San Francisco, CA (SFO) to Houston, TX (IAH), one direction. Airlines that report to the DOT only.
Method
Rates use all scheduled flights as the denominator; cancelled and diverted flights count as not on time. Figures based on fewer than 50 scheduled flights are suppressed. Full methodology.

Independent reference site. No government or airline affiliation or endorsement.