STL to SAT flight delays
St. Louis, MO (STL) San Antonio, TX (SAT) · 786 miles
547 flights · January 2025 – August 2026 · US Bureau of Transportation Statistics
80.96%
Arrived on time
Within 15 minutes of schedule
0.18%
Cancelled
Share of scheduled flights
53 min
When late, late by
Average across delayed arrivals
11 min
Delay per flight
Averaged over every flight flown
What the record says about this route
The season swings this route hard. In January it ran 36 points more punctual than in June — a difference bigger than the one between the best and worst airlines on most routes. If the date is flexible, it is worth more than the carrier.
Only Southwest Airlines flies this route in the published record, so there is no choice to weigh — the route's figures and the airline's are the same figures.
This is a thin route — 547 flights across the whole period. On a route this infrequent a cancellation is far more costly than the rate suggests, because the next departure may not be the same day.
The St. Louis to San Antonio route sits close to the middle of the record — neither notably punctual nor notably late.
Which airline should you fly on this route?
Over January 2025 – August 2026, Southwest Airlines arrived on time most often on STL to SAT. Flights ran closest to schedule in January and worst in June.
Every airline on STL to SAT
Ranked by how many flights each one operated. A carrier with fewer than 100 flights in the period is listed but not graded.
| Airline | Flights | On time | Cancelled | Avg delay | Grade |
|---|---|---|---|---|---|
| Southwest Airlines | 547 | 80.96% | 0.18% | 53 min | B |
Month by month
Share of flights that arrived within 15 minutes of schedule, by month flown.
The return leg
SAT to STL San Antonio back to St. Louis 85.71% on time AOther routes from St. Louis
Common questions
Are flights from St. Louis to San Antonio usually delayed?
80.96% of flights on the STL to SAT route arrived within 15 minutes of schedule, so roughly 2 in every ten arrived late. That is better than the average route in this record.
Which airlines fly from St. Louis to San Antonio?
Only Southwest Airlines appears in the published record on this route, with 547 flights and 80.96% arriving on time.
How often are STL to SAT flights cancelled?
0.18% of scheduled flights did not operate — about 2 in every thousand. That is in the normal range.
What is the best month to fly St. Louis to San Antonio?
January, when 92.9% of flights arrived on time. The worst was June at 56.9%.
When STL to SAT flights are late, how late are they?
About 53 minutes on average across the flights that arrived more than 15 minutes behind schedule.
What these figures do and do not tell you
Everything on this page is counted from the flights that actually operated on STL to SAT during January 2025 – August 2026, as reported by the airlines to the US Bureau of Transportation Statistics. "On time" is the federal definition: arriving at the gate within 15 minutes of the scheduled time.
A route's record is a description of the past, not a forecast. Weather, air traffic control and the aircraft's earlier flights that day drive most delays, and none of them are predictable from a historical rate. What the record does tell you is whether this route runs late more often than others, and which carrier on it has the better history — which is the part you can actually act on when you book.
Cancellations are counted separately from delays because they are a different problem for a traveller: a late flight still gets you there. How the grade is calculated →