Carrier route record
WNSAN→AUS
Southwest Airlines · San Diego to Austin
- Flights
- 1,429
- Period
- July 2025 to June 2026
- Share of route
- 56%
- Carriers
- 3
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with Southwest Airlines.
Southwest on SAN to AUS sits in the middle of the pack with a C+. About seven flights in ten arrive on time by the DOT's definition, 9 points worse than the national rate of 77.6%. The late ones land about 50 minutes behind schedule. That rests on 1,429 flights, with a median arrival 2 minutes late.
The national on-time rate over the same period is 77.6%, so Southwest on SAN to AUS runs 9 points behind the country as a whole. Across a thousand flights that is about 94 extra late arrivals.
Key figures
On time
68.2%
Arrivals under 15 minutes late, of 1,416 completed flights
Avg delay
50 min
Across delayed arrivals only, not all flights
Cancelled
0.56%
National rate is 1.81%
Whole route
73.0%
Every carrier on SAN to AUS, 2,552 flights
These figures cover 1,429 flights between July 2025 and June 2026. Beyond the headline rate, 8.7% of arrivals land a full hour or more behind schedule. That is the number that wrecks a connection, and it is not visible in an on-time percentage alone.
Carrier by carrier
Southwest against every carrier on SAN to AUS
Southwest flew 1,429 of the 2,552 flights on SAN to AUS, most of the route. Its 68.2% on time is 5 points worse than the route as a whole, which runs 73.0%. Ranked by on-time rate it is last of three carriers on the route, where the range runs from SkyWest at 80.1% to Southwest at 68.2%. One of those carriers flew fewer than 365 flights here, so treat their positions as rough.
Only one carrier clears this site's 365-flight floor here, so there is no comparison to draw. The table below is the full picture.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| SkyWest Airlines | 1,000 | 80.1% | 62 min | 1.30% | B |
| Frontier Airlinesthin sample | 123 | 70.2% | 48 min | 1.63% | C |
| Southwest Airlines (this page) | 1,429 | 68.2% | 50 min | 0.56% | C+ |
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 56 points, against half a point between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am332 flights88.4%
- 8am–11am308 flights73.0%
- 11am–2pm94 flights67.4%
- 2pm–5pm315 flights52.7%
- 5pm–8pm327 flights64.2%
- 8pm–5am53 flights32.7%
Scale runs 25% to 95%. Rows with fewer than 30 flights show a dash.
The 8pm–5am window is where this operation falls apart: 32.7% on time, against 88.4% for the 5am–8am slot. By evening the aircraft flying these rotations have absorbed a full day of small delays and there is no slack left to recover in. The 5am–8am window is the busiest, with 332 flights scheduled in it.
Across the year
Southwest on SAN to AUS through the year
June is the worst month at 43.8% on time, 46 points below January, the best at 89.7%. 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. May was the busiest month here, with 131 flights.
Across the week, Tuesday is the strongest day at 79.6% on time and Monday the weakest at 60.4%. 19 points is a smaller lever than departure hour, but it is free.
Delay causes
Why Southwest runs late on this route
One category carries most of the weight here. Late-arriving aircraft accounts for 61% of the 22,000 delay minutes carriers reported, and the remaining four split what is left. The split is by minutes rather than by flights, so a few very long delays count for as much as many short ones.
- 61%Late-arriving aircraft
- 23%Carrier
- 15%National Airspace System
- 0%Security
61% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. That is a cascade, and cascades start small and grow through the day. Across 22,000 reported delay minutes here, that single category outweighs weather by 61 to one. It is the strongest argument for booking the first departure of the morning, when the aircraft has been sitting at the gate overnight with nothing to inherit. The split is drawn from 22,488 reported delay minutes.
The practical consequence: the 5am–8am departure is the one that starts clean. Its aircraft has no earlier leg to be late from, which is exactly why that window shows 88.4% on time here.
Cancellations are rare at 0.56%, below the national 1.81% and low enough to earn the plus on the grade. Roughly one flight in 100 is called off; the risk here is arriving late, not not arriving.
Connections and stage length
What a delay here costs
8.7% of arrivals land an hour or more late, close to the national 8.1%. That is the figure that decides a connection, and it says a 60 to 75 minute layover is reasonable here while anything under 45 minutes is a bet. Most delays on this route last about 50 minutes, which a normal layover absorbs.
The 1,164 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. It is also long enough that the aircraft usually flies three or four legs a day rather than six, which slows how fast delay compounds.
The return leg runs 70.4% on time across 1,422 flights, within 2 points of this direction. The two legs are scored separately because they usually differ; on this city pair they happen not to.
The sample behind these figures is 1,429 flights, enough that the headline rate is stable to within roughly a point. The hour-block and month splits divide that further, so read the thinner bars with more caution than the headline.
What to do with this
Booking Southwest on SAN to AUS
Put together: the calendar is the biggest lever here, not the carrier or the hour. January runs 89.7% on time and June 43.8%, a swing of 46 points. If the dates move at all, move them out of June before you think about anything else. 1,416 completed flights over 12 months sit behind that.
Related
Where to go next
- SAN to AUS, every carrier
- Southwest on AUS to SAN, the return leg
- SkyWest Airlines on SAN to AUS80.1%
- Frontier Airlines on SAN to AUS70.2%
- Southwest Airlines network-wide record
- San Diego International (SAN) delay statistics
- Austin-Bergstrom International (AUS) delay statistics
- Why the first flight of the morning is statistically safest
- The best time of day to fly, according to 7.04 million flight records
Source: US DOT Bureau of Transportation Statistics, on-time performance data, July 2025 to June 2026. Last updated 15 September 2026; recomputed monthly. How this data is collected.