Carrier route record

ASSFO→SAN

Alaska Airlines · San Francisco to San Diego

Flights: 304
Period: July 2025 to June 2026
Share of route: 5%
Carriers: 5

Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with Alaska Airlines.

Alaska on SFO to SAN earns an A+. Close to nine flights in ten arrive inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 11 points better than the national rate of 77.6%. When something does go wrong the average delay runs roughly 50 minutes. That rests on 304 flights. The strongest carrier on the route with a full sample, United Airlines, flew 2,598 at 76.2% on time.

Set against the rest of the country, Alaska's SFO to SAN record is 11 points better than the US average of 77.6%. That gap is worth roughly 112 fewer late arrivals for every thousand flights.

On time

88.8%

Arrivals under 15 minutes late, of 303 completed flights

Avg delay

49 min

Across delayed arrivals only, not all flights

Cancelled

0.33%

National rate is 1.81%

Whole route

66.6%

Every carrier on SFO to SAN, 6,548 flights

These figures cover 304 flights between July 2025 and June 2026. The median arrival is 6 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

Alaska against every carrier on SFO to SAN

Alaska flew 304 of the 6,548 flights on SFO to SAN, about 5% of it. Its 88.8% on time is 22 points better than the route as a whole, which runs 66.6%. Ranked by on-time rate it is first of five carriers on the route, where the range runs from Alaska at 88.8% to Southwest at 52.8%. 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 76.2% of the time; Southwest Airlines manages 52.8%. Sample sizes sit next to every figure, because a two-point gap across 1,935 flights means less than a ten-point one.

On-time performance by carrier on SFO to SAN
Airline	Flights	On time	Avg delay	Cancelled	Grade
Alaska Airlines (this page)thin sample	304	88.8%	49 min	0.33%	A+
United Airlines	2,598	76.2%	55 min	0.46%	B+
SkyWest Airlines	1,515	64.8%	57 min	2.05%	D
Frontier Airlinesthin sample	196	53.7%	76 min	3.06%	F−
Southwest Airlines	1,935	52.8%	62 min	1.24%	F

The spread between United and Southwest is 23 points, wide enough that it should decide the booking. On a hundred trips that is 23 more arrivals inside the on-time window.

Departure window

When Alaska runs best on this route

Departure time matters more here than the choice of carrier. The gap between the best and worst window is 17 points, against 23 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.

5am–8am261 flights91.2%
8am–11am43 flights73.8%
11am–2pm—
2pm–5pm—
5pm–8pm—
8pm–5am—

Scale runs 65% to 95%. Rows with fewer than 30 flights show a dash.

Book the early departure. Flights leaving between 5am–8am arrive on time 91.2% of the time, against 73.8% for the morning window. That is 17 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 5am–8am window is the busiest, with 261 flights scheduled in it.

Across the year

Alaska on SFO to SAN through the year

Jul–Sep 202591 flights87.9%
Oct–Dec 202573 flights83.6%
Jan–Mar 202650 flights96.0%
Apr–Jun 202690 flights89.9%

Scale runs 75% to 100%. 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 88.8% on time across 304 flights.

Alaska on SFO to SAN did not run the same all year. Its best quarter was Jan–Mar 2026 at 96.0% on time and its weakest Oct–Dec 2025 at 83.6%, a swing of 12 points on roughly 76 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 97.5% on time and Sunday the weakest at 83.3%. 14 points is a smaller lever than departure hour, but it is free.

Delay causes

Why Alaska runs late on this route

One category carries most of the weight here. Carrier accounts for 47% of the 1,650 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.

Carrier
47%
National Airspace System
45%
Late-arriving aircraft
6%
Security
1%
Extreme weather
1%

45% 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 741 minutes out of 1,650, against a national NAS share of 21%. The split is drawn from 1,650 reported delay minutes.

The largest share of delay minutes, 47%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. Unlike weather, that is a management outcome, and it is the category where the gap between two carriers on the same schedule is genuinely earned. It accounts for 782 of the 1,650 delay minutes reported here.

Cancellations are rare at 0.33%, 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

Badly late arrivals are rare here: only 3.3% 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 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 5am–8am window matters as much as it does.

The return leg is a different operation and performs like one: it runs 54.0% on time across 303 flights, 35 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 35 points of difference.

One caution: this is a thin sample. 304 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 SFO to SAN

Put together: treat all of this as provisional. 304 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 88.8% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 303 completed flights over 12 months sit behind that.

Where to go next

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.

Key figures