Carrier route record
WNLAX→SAT
Southwest Airlines · Los Angeles to San Antonio
- Flights
- 337
- Period
- September 2025 to August 2026
- Share of route
- 19%
- Carriers
- 4
Historical statistics for September 2025 to August 2026, not live status. For today’s flights, check with Southwest Airlines.
Southwest on LAX to SAT draws a C+. About one flight in three arrives at least 15 minutes late, and the typical late arrival is about 40 minutes behind schedule. Build slack into anything you connect to. That rests on 337 flights. The strongest carrier on the route with a full sample, SkyWest Airlines, flew 697 at 85.9% on time.
The national on-time rate over the same period is 77.3%, so Southwest on LAX to SAT runs 12 points behind the country as a whole. Across a thousand flights that is about 123 extra late arrivals.
Key figures
On time
65.0%
Arrivals under 15 minutes late, of 337 completed flights
Avg delay
40 min
Across delayed arrivals only, not all flights
Cancelled
0.00%
National rate is 1.89%
Whole route
81.6%
Every carrier on LAX to SAT, 1,814 flights
These figures cover 337 flights between September 2025 and August 2026. On-time means an arrival less than 15 minutes after the scheduled gate time, the same threshold the Department of Transportation uses in its own reports. Cancelled and diverted flights are excluded from the on-time rate and counted separately, which is why the cancellation column matters on its own.
Fare search by Aviasales, a Travelpayouts partner. Booking through it may earn this site a commission at no cost to you; it changes no figure here.
Carrier by carrier
Southwest against every carrier on LAX to SAT
Southwest flew 337 of the 1,814 flights on LAX to SAT, about 19% of it. Its 65.0% on time is 17 points worse than the route as a whole, which runs 81.6%. Ranked by on-time rate it is last of four carriers on the route, where the range runs from SkyWest at 85.9% to Southwest at 65.0%. One of those carriers flew fewer than 365 flights here, so treat their positions as rough.
The two carriers here are closely matched: half a point separate the best from the worst. At that spread, schedule and price are better tie-breakers than reliability. Sample sizes are shown so you can see which rows are worth weighing.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| SkyWest Airlines | 697 | 85.9% | 68 min | 0.29% | A+ |
| Delta Air Lines | 679 | 85.9% | 74 min | 0.29% | A+ |
| Spirit Airlinesthin sample | 101 | 79.4% | 93 min | 3.96% | B− |
| Southwest Airlines (this page)thin sample | 337 | 65.0% | 40 min | 0.00% | C+ |
No carrier stands out. SkyWest tops the table at 85.9%, half a point clear of the bottom, which is inside the range this kind of sample moves year to year.
Timetable by Aviasales, a Travelpayouts partner. Booking through it may earn this site a commission at no cost to you; it changes no figure here.
Departure window
When Southwest runs best on this route
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 25 points, against half a point between the best and worst carrier.
- 5am–8am15 flights—
- 8am–11am134 flights75.4%
- 11am–2pm104 flights61.5%
- 2pm–5pm66 flights50.0%
- 5pm–8pm18 flights—
- 8pm–5am—
Scale runs 40% to 80%. Rows with fewer than 30 flights show a dash.
Book the morning departure. Flights leaving between 8am–11am arrive on time 75.4% of the time, against 50.0% for the afternoon window. That is 25 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 8am–11am window is the busiest, with 134 flights scheduled in it.
Across the year
Southwest on LAX to SAT through the year
June is the worst month at 43.3% on time, 50 points below October, the best at 93.5%. Summer afternoon convection and peak-season schedules land on the same weeks every year, so this is a pattern you can book around rather than a run of bad luck. December was the busiest month here, with 33 flights.
Across the week, Wednesday is the strongest day at 76.7% on time and Sunday the weakest at 58.0%, a spread of 19 points.
Arrival by arrival
How late Southwest on LAX to SAT runs when it is late
Most of the lateness is short. 61 of the 118 late arrivals were under half an hour behind, and 15 reached an hour or more.
- 15+ min early14 flights4.2%
- Within 15 min205 flights60.8%
- 15–29 min late61 flights18.1%
- 30–59 min late42 flights12.5%
- 1–2 hours late10 flights3.0%
- 2+ hours late5 flights1.5%
Scale runs 0% to 100%.
Share of 337 completed flights by arrival against schedule.
37 of 136 late departures made up the time and arrived on time, 27% of them. In the other direction, 19 flights left on time yet arrived 15 minutes late or more, so that delay built up after pushback: in the air, in a holding pattern or on the ground at SAT.
The worst days
Worst days for Southwest on LAX to SAT
The latest arrival of the period was on 22 June 2026, 5 hours behind schedule; most of its delay minutes were filed as carrier-caused (crew, maintenance, fuelling, baggage). Three of the five worst days fell in June 2026.
| Date | Arrived late by | Largest filed cause |
|---|---|---|
| 22 June 2026 | 5 hours | Carrier |
| 18 June 2026 | 3 hours 26 minutes | Late-arriving aircraft |
| 16 March 2026 | 3 hours 7 minutes | Carrier |
| 13 June 2026 | 2 hours 18 minutes | Late-arriving aircraft |
| 24 November 2025 | 2 hours 2 minutes | Late-arriving aircraft |
Delay causes
Why Southwest runs late on this route
Carrier accounts for 46% of the 4,739 delay minutes carriers reported here, and the remaining four split what is left.
- 46%Carrier
- 44%Late-arriving aircraft
- 11%National Airspace System
44% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. Across 4,739 reported delay minutes here, that single category outweighs weather by 44 to one. The split is drawn from 4,739 reported delay minutes.
The largest share of delay minutes, 46%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. It accounts for 2,162 of the 4,739 delay minutes reported here.
Cancellations are rare at 0.00%, below the national 1.89% and low enough to earn the plus on the grade. Almost no flights are called off; the risk here is arriving late, not not arriving.
Connections and stage length
What a delay here costs
Badly late arrivals are rare here: only 4.5% land an hour or more behind schedule, against 8.3% nationally. Connections built on this flight are about as safe as US domestic connections get, though a cancelled flight still ignores every layover you give it.
The 1,211 miles between these two airports put this in the middle of the US network, around two and a half to three hours of block time. That is enough cruise to absorb a ten-minute late pushback and not enough to absorb thirty.
The return leg is a different operation and performs like one: it runs 72.1% on time across 337 flights, 7 points above this direction. Departure banks, aircraft rotations and the congestion at each end all differ, so scoring the two directions together would average away a real 7 points of difference.
One caution: this is a thin sample. 337 flights over twelve months is enough to clear this site's floor but not enough to pin the rate down tightly, and a single bad week moves it by more than a point. Treat the grade as a rough reading.
What to do with this
Booking Southwest on LAX to SAT
Put together: treat all of this as provisional. 337 flights over twelve months is enough to clear this site's floor and not enough to be confident to better than a couple of points. The 65.0% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 337 completed flights over 12 months sit behind that.
Related
Where to go next
- LAX to SAT, every carrier
- Southwest on SAT to LAX, the return leg
- SkyWest Airlines on LAX to SAT85.9%
- Delta Air Lines on LAX to SAT85.9%
- Spirit Airlines on LAX to SAT79.4%
- Southwest Airlines network-wide record
- Los Angeles International (LAX) delay statistics
- San Antonio International (SAT) delay statistics
- Why the first flight of the morning is statistically safest
- The best time of day to fly, according to 7.05 million flight records
Source: US DOT Bureau of Transportation Statistics, on-time performance data, September 2025 to August 2026. Last updated ; recomputed monthly. How this data is collected.