Carrier route record
WNSAN→FAT
Southwest Airlines · San Diego to Fresno
- 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 SAN to FAT lands a B, 3 points better than the national rate of 77.6%. About one flight in five arrives 15 minutes late or worse, and those flights are late by roughly 45 minutes on average. That is a workable record, not a spotless one. That rests on 512 flights, with a median arrival 13 minutes early.
The US average over the same twelve months is 77.6%, so there is little to separate Southwest on SAN to FAT from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.
Key figures
On time
80.2%
Arrivals under 15 minutes late, of 506 completed flights
Avg delay
44 min
Across delayed arrivals only, not all flights
Cancelled
1.17%
National rate is 1.81%
Whole route
78.9%
Every carrier on SAN to FAT, 1,747 flights
These figures cover 512 flights between July 2025 and June 2026. The median arrival is 13 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 SAN to FAT
Southwest flew 512 of the 1,747 flights on SAN to FAT, about 29% of it. Its 80.2% on time is about level with the route as a whole at 78.9%. Ranked by on-time rate it is first of two carriers on the route, where the range runs from Southwest at 80.2% to SkyWest at 78.3%.
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 |
|---|---|---|---|---|---|
| Southwest Airlines (this page) | 512 | 80.2% | 44 min | 1.17% | B |
| SkyWest Airlines | 1,235 | 78.3% | 47 min | 2.02% | 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 41 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–8am—
- 8am–11am234 flights97.0%
- 11am–2pm7 flights—
- 2pm–5pm5 flights—
- 5pm–8pm78 flights85.7%
- 8pm–5am188 flights56.0%
Scale runs 50% to 100%. Rows with fewer than 30 flights show a dash.
The 8pm–5am window is where this operation falls apart: 56.0% on time, against 97.0% for the 8am–11am 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 8am–11am window is the busiest, with 234 flights scheduled in it.
Across the year
Southwest on SAN to FAT through the year
Delays peak in October, when the on-time rate falls to 70.9%. January is the strongest month at 90.9%. Moving a flexible trip across that boundary buys 20 points. December was the busiest month here, with 60 flights.
Across the week, Tuesday is the strongest day at 84.4% on time and Thursday the weakest at 77.3%. 7 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 85% of the 4,385 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.
- 85%Late-arriving aircraft
- 12%Carrier
- 3%National Airspace System
85% 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 4,385 reported delay minutes here, that single category outweighs weather by 85 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 4,385 reported delay minutes.
The practical consequence: the 8am–11am departure is the one that starts clean. Its aircraft has no earlier leg to be late from, which is exactly why that window shows 97.0% on time here.
Cancellations sit at 1.17% against a national 1.81%, which is ordinary. Diversions add another 0.00%.
Connections and stage length
What a delay here costs
Badly late arrivals are rare here: only 4.2% land an hour or more behind schedule, against 8.1% 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.
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 8am–11am window matters as much as it does.
The return leg is a different operation and performs like one: it runs 75.0% on time across 512 flights, 5 points below 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 SAN to FAT
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 80.2% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 506 completed flights over 12 months sit behind that.
Related
Where to go next
- SAN to FAT, every carrier
- Southwest on FAT to SAN, the return leg
- SkyWest Airlines on SAN to FAT78.3%
- 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.