Carrier route record
UASFO→LAX
United Airlines · San Francisco to Los Angeles
- Flights
- 3,263
- Period
- July 2025 to June 2026
- Share of route
- 30%
- Carriers
- 8
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with United Airlines.
United on SFO to LAX lands a B+, about a point 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 50 minutes on average. That is a workable record, not a spotless one. That rests on 3,263 flights. The strongest carrier on the route with a full sample, SkyWest Airlines, flew 2,588 at 76.6% on time.
The US average over the same twelve months is 77.6%, so there is little to separate United on SFO to LAX from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.
Key figures
On time
78.4%
Arrivals under 15 minutes late, of 3,254 completed flights
Avg delay
49 min
Across delayed arrivals only, not all flights
Cancelled
0.28%
National rate is 1.81%
Whole route
73.9%
Every carrier on SFO to LAX, 11,015 flights
These figures cover 3,263 flights between July 2025 and June 2026. The median arrival is 4 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
United against every carrier on SFO to LAX
United flew 3,263 of the 11,015 flights on SFO to LAX, about 30% of it. Its 78.4% on time is 5 points better than the route as a whole, which runs 73.9%. Ranked by on-time rate it is first of eight carriers on the route, where the range runs from United at 78.4% to Envoy at 0.0%. Two of those carriers flew fewer than 365 flights here, so treat their positions as rough.
The choice of carrier is not cosmetic here. SkyWest Airlines arrives on time 76.6% of the time; Southwest Airlines manages 61.8%. Sample sizes sit next to every figure, because a two-point gap across 1,369 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| United Airlines (this page) | 3,263 | 78.4% | 49 min | 0.28% | B+ |
| American Airlinesthin sample | 345 | 76.7% | 108 min | 0.29% | B+ |
| SkyWest Airlines | 2,588 | 76.6% | 60 min | 1.04% | B |
| Delta Air Lines | 2,373 | 73.6% | 65 min | 1.56% | C |
| Alaska Airlines | 685 | 69.7% | 47 min | 0.73% | C+ |
| Frontier Airlines | 391 | 68.6% | 84 min | 1.53% | C |
| Southwest Airlines | 1,369 | 61.8% | 60 min | 0.58% | D+ |
| Envoy Airthin sample | 1 | 0.0% | 35 min | 0.00% | F+ |
The spread between SkyWest 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.
Flight by flight
United flight numbers on SFO to LAX
Departure window
When United runs best on this route
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 23 points, against 15 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am520 flights91.7%
- 8am–11am634 flights80.9%
- 11am–2pm435 flights77.0%
- 2pm–5pm452 flights73.0%
- 5pm–8pm653 flights78.8%
- 8pm–5am569 flights68.5%
Scale runs 60% to 95%. Rows with fewer than 30 flights show a dash.
Book the early departure. Flights leaving between 5am–8am arrive on time 91.7% of the time, against 68.5% for the overnight window. That is 23 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 5pm–8pm window is the busiest, with 653 flights scheduled in it.
Across the year
United on SFO to LAX through the year
December is the weak month at 70.8% on time, against 89.0% in March. Winter delays cluster: a single storm system can account for most of a month's shortfall, so an average December hides both very good weeks and genuinely unflyable days. October was the busiest month here, with 303 flights.
Across the week, Tuesday is the strongest day at 82.8% on time and Thursday the weakest at 73.5%. 9 points is a smaller lever than departure hour, but it is free.
Delay causes
Why United runs late on this route
One category carries most of the weight here. Late-arriving aircraft accounts for 51% of the 34,000 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.
- 51%Late-arriving aircraft
- 29%Carrier
- 20%National Airspace System
- 0%Extreme weather
51% 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 34,000 reported delay minutes here, that single category outweighs weather by 51 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 34,108 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 91.7% on time here.
Cancellations are rare at 0.28%, 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
5.3% 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 roughly 50 minutes, which a normal layover absorbs.
At 337 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 66.3% on time across 3,257 flights, 12 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 12 points of difference.
The sample behind these figures is 3,263 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 United on SFO to LAX
Put together: the calendar is the biggest lever here, not the carrier or the hour. March runs 89.0% on time and December 70.8%, a swing of 18 points. If the dates move at all, move them out of December before you think about anything else. 3,254 completed flights over 12 months sit behind that.
Related
Where to go next
- SFO to LAX, every carrier
- United on LAX to SFO, the return leg
- American Airlines on SFO to LAX76.7%
- SkyWest Airlines on SFO to LAX76.6%
- Delta Air Lines on SFO to LAX73.6%
- Alaska Airlines on SFO to LAX69.7%
- Frontier Airlines on SFO to LAX68.6%
- Southwest Airlines on SFO to LAX61.8%
- United Airlines network-wide record
- San Francisco International (SFO) delay statistics
- Los Angeles International (LAX) delay statistics
- Why the first flight of the morning is statistically safest
- Same route, different airline: where the carrier you pick matters most
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.