Carrier route record
WNOAK→SAN
Southwest Airlines · Oakland to San Diego
- Flights
- 2,939
- Period
- July 2025 to June 2026
- Share of route
- 92%
- Carriers
- 3
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with Southwest Airlines.
Southwest on OAK to SAN draws a C+. About one flight in three arrives at least 15 minutes late, and the typical late arrival is about 50 minutes behind schedule. Build slack into anything you connect to. That rests on 2,939 flights, with a median arrival 3 minutes late.
The national on-time rate over the same period is 77.6%, so Southwest on OAK to SAN runs 11 points behind the country as a whole. Across a thousand flights that is about 110 extra late arrivals.
Key figures
On time
66.6%
Arrivals under 15 minutes late, of 2,908 completed flights
Avg delay
49 min
Across delayed arrivals only, not all flights
Cancelled
0.95%
National rate is 1.81%
Whole route
66.9%
Every carrier on OAK to SAN, 3,201 flights
These figures cover 2,939 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 OAK to SAN
Southwest flew 2,939 of the 3,201 flights on OAK to SAN, most of the route. Its 66.6% on time is about level with the route as a whole at 66.9%. Ranked by on-time rate it is last of three carriers on the route, where the range runs from Spirit at 78.2% to Southwest at 66.6%. Two 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 |
|---|---|---|---|---|---|
| Spirit Airlinesthin sample | 55 | 78.2% | 63 min | 0.00% | B+ |
| SkyWest Airlinesthin sample | 207 | 68.6% | 51 min | 1.45% | C |
| Southwest Airlines (this page) | 2,939 | 66.6% | 49 min | 0.95% | 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 44 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–8am520 flights91.4%
- 8am–11am632 flights74.3%
- 11am–2pm462 flights67.9%
- 2pm–5pm586 flights58.7%
- 5pm–8pm466 flights48.4%
- 8pm–5am273 flights47.4%
Scale runs 40% to 95%. Rows with fewer than 30 flights show a dash.
The 8pm–5am window is where this operation falls apart: 47.4% on time, against 91.4% 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 8am–11am window is the busiest, with 632 flights scheduled in it.
Across the year
Southwest on OAK to SAN through the year
June is the worst month at 54.5% on time, 23 points below January, the best at 77.2%. 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. July was the busiest month here, with 271 flights.
Across the week, Saturday is the strongest day at 77.6% on time and Friday the weakest at 58.3%. 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 44% of the 48,000 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.
- 44%Late-arriving aircraft
- 29%National Airspace System
- 26%Carrier
- 1%Extreme weather
- 0%Security
44% 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 48,000 reported delay minutes here, that single category outweighs weather by 44 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 47,964 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 91.4% on time here.
Cancellations sit at 0.95% against a national 1.81%, which is ordinary. Diversions add another 0.10%.
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.
At 446 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 74.5% on time across 2,940 flights, 8 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 8 points of difference.
The sample behind these figures is 2,939 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 OAK to SAN
Put together: the calendar is the biggest lever here, not the carrier or the hour. January runs 77.2% on time and June 54.5%, a swing of 23 points. If the dates move at all, move them out of June before you think about anything else. 2,908 completed flights over 12 months sit behind that.
Related
Where to go next
- OAK to SAN, every carrier
- Southwest on SAN to OAK, the return leg
- SkyWest Airlines on OAK to SAN68.6%
- Southwest Airlines network-wide record
- Oakland International (OAK) delay statistics
- 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.