Carrier route record
WNSAN→OAK
Southwest Airlines · San Diego to Oakland
- Flights
- 2,940
- 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 SAN to OAK sits in the middle of the pack with a C. 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 about 50 minutes behind schedule. That rests on 2,940 flights, with a median arrival 3 minutes early.
The US average over the same twelve months is 77.6%, so there is little to separate Southwest on SAN to OAK from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.
Key figures
On time
74.5%
Arrivals under 15 minutes late, of 2,907 completed flights
Avg delay
50 min
Across delayed arrivals only, not all flights
Cancelled
1.09%
National rate is 1.81%
Whole route
74.5%
Every carrier on SAN to OAK, 3,195 flights
These figures cover 2,940 flights between July 2025 and June 2026. The median arrival is 3 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 OAK
Southwest flew 2,940 of the 3,195 flights on SAN to OAK, most of the route. Its 74.5% on time is about level with the route as a whole at 74.5%. Ranked by on-time rate it is number two of three carriers on the route, where the range runs from Spirit at 83.6% to SkyWest at 72.6%. 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 | 83.6% | 57 min | 0.00% | B+ |
| Southwest Airlines (this page) | 2,940 | 74.5% | 50 min | 1.09% | C |
| SkyWest Airlinesthin sample | 200 | 72.6% | 54 min | 1.50% | 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–8am349 flights97.7%
- 8am–11am585 flights88.4%
- 11am–2pm476 flights77.4%
- 2pm–5pm637 flights66.9%
- 5pm–8pm535 flights64.5%
- 8pm–5am358 flights53.5%
Scale runs 45% to 100%. Rows with fewer than 30 flights show a dash.
The 8pm–5am window is where this operation falls apart: 53.5% on time, against 97.7% 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 2pm–5pm window is the busiest, with 637 flights scheduled in it.
Across the year
Southwest on SAN to OAK through the year
June is the worst month at 60.5% on time, 23 points below January, the best at 83.6%. 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, Tuesday is the strongest day at 84.1% on time and Friday the weakest at 68.0%. 16 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 73% of the 37,000 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.
- 73%Late-arriving aircraft
- 24%Carrier
- 3%National Airspace System
- 0%Security
73% 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 37,000 reported delay minutes here, that single category outweighs weather by 73 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 36,814 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 97.7% on time here.
Cancellations sit at 1.09% against a national 1.81%, which is ordinary. Diversions add another 0.03%.
Connections and stage length
What a delay here costs
6.8% 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 66.6% on time across 2,939 flights, 8 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 8 points of difference.
The sample behind these figures is 2,940 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 OAK
Put together: the calendar is the biggest lever here, not the carrier or the hour. January runs 83.6% on time and June 60.5%, a swing of 23 points. If the dates move at all, move them out of June before you think about anything else. 2,907 completed flights over 12 months sit behind that.
Related
Where to go next
- SAN to OAK, every carrier
- Southwest on OAK to SAN, the return leg
- SkyWest Airlines on SAN to OAK72.6%
- Southwest Airlines network-wide record
- San Diego International (SAN) delay statistics
- Oakland International (OAK) 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.