PlainFlights

Route · IAH → SAT · 2020–2025 BTS data

Houston to San Antonio

According to PlainFlights' route traffic ranking (BTS On-Time Performance total flights), IAH to SAT (Houston to San Antonio) ranks #805 of 4927 tracked domestic routes by total flights (most flights = #1).

Data updated 2026-06-13

81.1%
On-time
+2.1 pts
vs US avg
70 min
Delay when late
13,003
Flights
#805 of 4927
Corpus placement

Cancelled

1.7%

Best Month

Sep 2025 87%

Worst Month

Jul 2024 59%

Distance

191 mi

Carriers

12

Monthly Performance

Recent 24 months of route data.

Period Flights Delayed Cancelled Diverted Carriers
Dec 2025 217 35 0 0 UA,OO
Nov 2025 207 34 2 0 OO,UA
Oct 2025 213 31 0 0 UA
Sep 2025 229 29 0 0 UA,OO
Aug 2025 208 44 1 0 OO,UA
Jul 2025 185 52 2 0 OO,UA
Jun 2025 212 57 9 0 OO,UA
May 2025 199 39 3 0 OO,UA
Apr 2025 142 23 0 1 OO,UA
Mar 2025 230 44 0 0 OO,UA
Feb 2025 188 39 0 0 OO,UA
Jan 2025 176 34 9 1 OO,UA
Dec 2024 182 46 3 1 OO,UA
Nov 2024 222 33 0 1 OO,UA
Oct 2024 234 36 0 0 UA,OO
Sep 2024 230 41 0 0 OO,UA
Aug 2024 218 55 3 0 OO,UA
Jul 2024 200 83 17 0 OO,UA
Jun 2024 139 43 3 0 OO,UA
May 2024 145 57 5 0 OO,UA
Apr 2024 151 36 1 0 OO,UA
Mar 2024 114 30 1 0 OO,UA
Feb 2024 130 21 0 0 OO,UA
Jan 2024 158 38 19 0 OO,UA

IAH–SAT seasonal on-time pattern

Best: September (85.0%) · weakest: July (71.2%)

70%75%80%85%90% JanFebMarAprMayJunJulAugSepOctNovDec 82.6%

Strongest calendar month

September

85.0% on-time · ~195 flights/mo

Busiest calendar month

October

~200 flights/mo avg

Weakest calendar month

July

71.2% on-time · ~182 flights/mo

Cancellation Rate

1.7%

78 of 4,529 flights

Diversion Rate

0.1%

4 of 4,529 flights

Explore origin & destination

On-time and delay data for the airports this route connects.

IAH - Houston

Full on-time, delay-cause, and seasonal performance for Houston, TX.

IAH on-time profile

SAT - San Antonio

Full on-time, delay-cause, and seasonal performance for San Antonio, TX.

SAT on-time profile

Compare the two airports

See IAH and SAT side by side on delays, cancellations, and reliability.

Compare IAH vs SAT

Origin-hub reliability standing

Mid-pack among IAH departures

From IAH, this corridor sits with 79 other 75–85% on-time routes out of 102 tracked departures, not the hub's reliability leaders (17 at ≥85%) and not the softest ( 6 below 75%). Destination: San Antonio · fleet on-time rank #2698 of 4927.

What the Data Says About IAH to SAT

13,003 tracked flights put the IAH to SAT pairing (Houston to San Antonio) at a 81.1% on-time rate, squarely in line with the wider network. Delays that do occur run 70.3 minutes on average. Across the 191-mile route and its 12 carriers, the trailing 24 months show 1.7% cancelled and 0.1% diverted (4,529 flights sampled).

The monthly split is wide on this route: Sep 2025 posted the strongest performance at 87% on-time, while Jul 2024 came in at just 59% - a 29-point swing worth factoring into travel timing.

On the multi-year calendar, IAH–SAT peaks in September at 85.0% on-time while October carries the heaviest traffic (~200 flights per month) ; the softest month is July at 71.2%, a 13.8-point swing that repeats because the corridor's weather and holiday mix stays stable year to year.

Frequently Asked Questions

Where does IAH to SAT rank among US routes by traffic? ▼
According to PlainFlights' route traffic ranking, IAH to SAT ranks #805 of 4927 tracked domestic routes by total flights (most flights = #1). That ordinal matches our busiest-routes listing (total_flights DESC). See /methodology#corpus-placement for the exact sort basis.
How often are flights delayed from IAH to SAT? ▼
Flights from Houston to San Antonio have a 81.1% on-time rate based on 13,003 flights. The average delay is 70.3 minutes. The best recent month was Sep 2025 with 87% on-time.
What is the cancellation rate for IAH to SAT? ▼
Over the last 24 months, 1.7% of flights on this route were cancelled (78 of 4,529 flights) and 0.1% were diverted.
How far is the flight from IAH to SAT? ▼
The flight distance from Houston (IAH) to San Antonio (SAT) is approximately 191 miles. This route is served by 12 carriers.
When is the best time to fly from IAH to SAT? ▼
The best recent month for on-time performance was Sep 2025 (87% on-time). The worst was Jul 2024 (59% on-time). Consider booking during months with historically better performance.

Airports on this route

IAH Airport

Houston
SAT Airport

San Antonio
Data source

Data Source: Bureau of Transportation Statistics (BTS), On-Time Performance Data. Statistics reflect cumulative performance across all available reporting periods.

Read our methodology - how this data is sourced, computed, and verified.

Using IAH–SAT data

IAH–SAT is mid-pack at 81.1% on-time; month and carrier mix move more than the corridor headline.

  • Compare IAH and SAT airport profiles: delay causes and top routes differ even on the same corridor. IAH airport
  • If your dates flex, September (85.0% on-time) beats July (71.2%) on this corridor. Seasonal chart
  • 4 other routes post a similar 81.1% on-time rate; compare before you commit to this pairing. Similar routes

On-time rate reflects the BTS historical average across all reporting carriers on this origin–destination pair, not any single flight or booking recommendation.

Data sourced from U.S. Department of Transportation Bureau of Transportation Statistics (BTS) On-Time Performance data. See our methodology for details. Retrieved and formatted by PlainFlights

Every figure on PlainFlights is rendered directly from BTS On-Time Performance data, no number is typed in by an editor. This page aggregates this specific route's on-time performance and monthly trend, live from the dataset. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.