Carrier route record
ASSAN→SFO
Alaska Airlines · San Diego to San Francisco
- Flights
- 331
- Period
- September 2025 to August 2026
- Share of route
- 5%
- Carriers
- 5
Historical statistics for September 2025 to August 2026, not live status. For today’s flights, check with Alaska Airlines.
Alaska on SAN to SFO earns an F, which is as low as this site's scale goes for a reason. Only 53.1% of flights arrive inside the 15-minute window, 24 points worse than the national rate of 77.3%. Late arrivals average roughly 50 minutes. Treat any tight connection here as a coin flip. That rests on 331 flights. The strongest carrier on the route with a full sample, United Airlines, flew 2,666 at 67.2% on time.
United Airlines is the most reliable of the three carriers covered here at 67.2% on time across 2,666 flights.
Key figures
On time
53.1%
Arrivals under 15 minutes late, of 326 completed flights
Avg delay
52 min
Across delayed arrivals only, not all flights
Cancelled
1.51%
National rate is 1.89%
Whole route
59.5%
Every carrier on SAN to SFO, 6,763 flights
These figures cover 331 flights between September 2025 and August 2026. Beyond the headline rate, 15.0% of arrivals land a full hour or more behind schedule, against 8.3% nationally.
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Carrier by carrier
Alaska against every carrier on SAN to SFO
Alaska flew 331 of the 6,763 flights on SAN to SFO, about 5% of it. Its 53.1% on time is 6 points worse than the route as a whole, which runs 59.5%. Ranked by on-time rate it is number three of five carriers on the route, where the range runs from United at 67.2% to Frontier at 37.9%. One of those carriers flew fewer than 365 flights here, so treat their positions as rough.
The choice of carrier is not cosmetic here. United Airlines arrives on time 67.2% of the time; Southwest Airlines manages 52.4%. Sample sizes sit next to every figure, because a two-point gap across 2,070 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| United Airlines | 2,666 | 67.2% | 57 min | 0.56% | C+ |
| SkyWest Airlines | 1,482 | 59.8% | 64 min | 1.96% | D |
| Alaska Airlines (this page)thin sample | 331 | 53.1% | 52 min | 1.51% | F |
| Southwest Airlines | 2,070 | 52.4% | 61 min | 1.30% | F |
| Frontier Airlinesthin sample | 214 | 37.9% | 75 min | 5.14% | F− |
The spread between United and Southwest is 15 points, wide enough that it should decide the booking. On a hundred trips that is 15 more arrivals inside the on-time window.
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Departure window
When Alaska runs best on this route
Departure time is the single lever a traveller controls, and it moves the odds more than most people expect. Each bar below is the on-time rate for flights scheduled to leave inside that window, across 331 flights.
The overnight block holds up unusually well at 53.2% on time across 283 flights. Red-eyes fly into empty airspace and empty gates, and they are the first rotation of the aircraft's day rather than the last. The 8pm–5am window is the busiest, with 283 flights scheduled in it.
Across the year
Alaska on SAN to SFO through the year
- Jul–Sep 202528 flights—
- Oct–Dec 202573 flights68.5%
- Jan–Mar 202650 flights80.0%
- Apr–Jun 202691 flights36.0%
- Jul–Sep 202689 flights43.7%
Scale runs 30% to 85%. Rows with fewer than 30 flights show a dash.
Monthly volumes are too low here to break the year into twelve reliable readings. What the twelve-month total says is 53.1% on time across 331 flights.
Alaska on SAN to SFO did not run the same all year. Its best quarter was Jan–Mar 2026 at 80.0% on time and its weakest Apr–Jun 2026 at 36.0%, a swing of 44 points on roughly 83 flights a quarter. The twelve-month rate averages over that, so if you are flying in a weak quarter the quarter's own figure is the better guide.
Across the week, Saturday is the strongest day at 70.5% on time and Friday the weakest at 39.1%, a spread of 31 points.
Arrival by arrival
How late Alaska on SAN to SFO runs when it is late
The 153 late arrivals split 38 under half an hour, 66 between 30 and 60 minutes, and 49 an hour or more.
- 15+ min early73 flights22.4%
- Within 15 min100 flights30.7%
- 15–29 min late38 flights11.7%
- 30–59 min late66 flights20.2%
- 1–2 hours late44 flights13.5%
- 2+ hours late5 flights1.5%
Scale runs 0% to 100%.
Share of 326 completed flights by arrival against schedule.
23 of 158 late departures made up the time and arrived on time, 15% of them. In the other direction, 18 flights left on time yet arrived 15 minutes late or more, so that delay built up after pushback: in the air, in a holding pattern or on the ground at SFO.
The worst days
Worst days for Alaska on SAN to SFO
The latest arrival of the period was on 25 October 2025, 2 hours 52 minutes behind schedule; most of its delay minutes were filed as a late-arriving aircraft. Three of the five worst days fell in October 2025.
| Date | Arrived late by | Largest filed cause |
|---|---|---|
| 25 October 2025 | 2 hours 52 minutes | Late-arriving aircraft |
| 24 October 2025 | 2 hours 27 minutes | Late-arriving aircraft |
| 3 June 2026 | 2 hours 23 minutes | National Airspace System |
| 8 June 2026 | 2 hours 7 minutes | National Airspace System |
| 14 October 2025 | 2 hours 2 minutes | Late-arriving aircraft |
Delay causes
Why Alaska runs late on this route
National Airspace System accounts for 58% of the 7,917 delay minutes carriers reported here, and the remaining four split what is left.
- 58%National Airspace System
- 33%Late-arriving aircraft
- 8%Carrier
- 1%Extreme weather
58% 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 4,599 minutes out of 7,917, against a national NAS share of 21%. The split is drawn from 7,917 reported delay minutes.
Cancellations sit at 1.51% against a national 1.89%, which is ordinary. Diversions add another 0.00%.
Connections and stage length
What a delay here costs
15.0% of arrivals land a full hour or more behind schedule, against 8.3% nationally. Ninety minutes is the honest minimum for a connection here, and two hours if the onward flight is on a separate ticket.
At 447 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 8pm–5am window matters as much as it does.
The return leg is a different operation and performs like one: it runs 82.9% on time across 331 flights, 30 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 30 points of difference.
One caution: this is a thin sample. 331 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 Alaska on SAN to SFO
Put together: treat all of this as provisional. 331 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 53.1% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 326 completed flights over 12 months sit behind that.
Related
Where to go next
- SAN to SFO, every carrier
- Alaska on SFO to SAN, the return leg
- United Airlines on SAN to SFO67.2%
- SkyWest Airlines on SAN to SFO59.8%
- Southwest Airlines on SAN to SFO52.4%
- Frontier Airlines on SAN to SFO37.9%
- Alaska Airlines network-wide record
- San Diego International (SAN) delay statistics
- San Francisco International (SFO) delay statistics
- Same route, different airline: where the carrier you pick matters most
- Why the first flight of the morning is statistically safest
Source: US DOT Bureau of Transportation Statistics, on-time performance data, September 2025 to August 2026. Last updated ; recomputed monthly. How this data is collected.