Carrier route record
WNFAT→SAN
Southwest Airlines · Fresno to San Diego
- Flights
- 512
- Period
- July 2025 to June 2026
- Share of route
- 29%
- Carriers
- 2
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with Southwest Airlines.
Southwest on FAT to SAN sits in the middle of the pack with a B+. Close to three flights in four arrive on time by the DOT's definition, 3 points worse than the national rate of 77.6%. The late ones land roughly 55 minutes behind schedule. That rests on 512 flights, with a median arrival 5 minutes early.
The US average over the same twelve months is 77.6%, so there is little to separate Southwest on FAT to SAN from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.
Key figures
On time
75.0%
Arrivals under 15 minutes late, of 509 completed flights
Avg delay
54 min
Across delayed arrivals only, not all flights
Cancelled
0.39%
National rate is 1.81%
Whole route
76.2%
Every carrier on FAT to SAN, 1,747 flights
These figures cover 512 flights between July 2025 and June 2026. The median arrival is 5 minutes early, which is the part an average hides: most flights here are fine, and the on-time rate is decided by a tail of badly late ones. On-time means under 15 minutes late, the DOT's own threshold.
Carrier by carrier
Southwest against every carrier on FAT to SAN
Southwest flew 512 of the 1,747 flights on FAT to SAN, about 29% of it. Its 75.0% on time is about level with the route as a whole at 76.2%. Ranked by on-time rate it is last of two carriers on the route, where the range runs from SkyWest at 76.7% to Southwest at 75.0%.
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 | 1,235 | 76.7% | 53 min | 1.62% | B |
| Southwest Airlines (this page) | 512 | 75.0% | 54 min | 0.39% | B+ |
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 57 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–8am203 flights92.6%
- 8am–11am65 flights70.3%
- 11am–2pm1 flights—
- 2pm–5pm150 flights77.7%
- 5pm–8pm93 flights35.5%
- 8pm–5am—
Scale runs 25% to 100%. Rows with fewer than 30 flights show a dash.
The 5pm–8pm window is where this operation falls apart: 35.5% on time, against 92.6% 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 203 flights scheduled in it.
Across the year
Southwest on FAT to SAN through the year
June is the worst month at 58.9% on time, 32 points below November, the best at 91.1%. 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 60 flights.
Across the week, Sunday is the strongest day at 82.1% on time and Thursday the weakest at 70.7%. 11 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. National Airspace System accounts for 46% of the 6,790 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.
- 46%National Airspace System
- 38%Late-arriving aircraft
- 12%Carrier
- 4%Extreme weather
38% 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 6,790 reported delay minutes here, that single category outweighs weather by 10 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 6,790 reported delay minutes.
46% of delay minutes are charged to the National Airspace System: air traffic volume, runway configuration, ground stops. No carrier can price its way out of that, which is why airport choice moves the number here more than carrier choice does. That is 3,145 minutes out of 6,790, against a national NAS share of 21%.
Cancellations are rare at 0.39%, 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
7.9% 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 roughly 55 minutes, which a normal layover absorbs.
At 314 miles this is a short hop, and stage length matters more than it looks. A flight this short spends under two hours in the air, which leaves almost nothing to claw back a late pushback with. Delay here is decided on the ground, in the turn, which is why the 5am–8am window matters as much as it does.
The return leg is a different operation and performs like one: it runs 80.2% on time across 512 flights, 5 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 5 points of difference.
One caution: this is a thin sample. 512 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 FAT to SAN
Put together: treat all of this as provisional. 512 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 75.0% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 509 completed flights over 12 months sit behind that.
Related
Where to go next
- FAT to SAN, every carrier
- Southwest on SAN to FAT, the return leg
- SkyWest Airlines on FAT to SAN76.7%
- Southwest Airlines network-wide record
- San Diego International (SAN) 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.