Carrier route record
UASBP→SFO
United Airlines · San Luis Obispo to San Francisco
- Flights
- 180
- Period
- July 2025 to June 2026
- Share of route
- 16%
- Carriers
- 2
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with United Airlines.
United on SBP to SFO draws a D. Roughly one flight in three arrives at least 15 minutes late, and the typical late arrival is an hour and a half behind schedule. Build slack into anything you connect to. That rests on 180 flights, with a median arrival 6 minutes late.
The national on-time rate over the same period is 77.6%, so United on SBP to SFO runs 17 points behind the country as a whole. Across a thousand flights that is about 169 extra late arrivals.
Key figures
On time
60.7%
Arrivals under 15 minutes late, of 178 completed flights
Avg delay
86 min
Across delayed arrivals only, not all flights
Cancelled
1.11%
National rate is 1.81%
Whole route
62.1%
Every carrier on SBP to SFO, 1,145 flights
These figures cover 180 flights between July 2025 and June 2026. Beyond the headline rate, 15.2% 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
United against every carrier on SBP to SFO
United flew 180 of the 1,145 flights on SBP to SFO, about 16% of it. Its 60.7% on time is about level with the route as a whole at 62.1%. Ranked by on-time rate it is last of two carriers on the route, where the range runs from SkyWest at 62.3% to United at 60.7%.
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 |
|---|---|---|---|---|---|
| SkyWest Airlines | 965 | 62.3% | 67 min | 1.14% | D |
| United Airlines (this page)thin sample | 180 | 60.7% | 86 min | 1.11% | D |
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 59 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–8am133 flights76.3%
- 8am–11am—
- 11am–2pm—
- 2pm–5pm41 flights17.1%
- 5pm–8pm—
- 8pm–5am6 flights—
Scale runs 10% to 80%. Rows with fewer than 30 flights show a dash.
Book the early departure. Flights leaving between 5am–8am arrive on time 76.3% of the time, against 17.1% for the afternoon window. That is 59 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 133 flights scheduled in it.
Across the year
United on SBP to SFO through the year
- Jan–Mar 202642 flights85.4%
- Apr–Jun 2026138 flights53.3%
Scale runs 45% to 90%. 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 60.7% on time across 180 flights.
Split by quarter, United on SBP to SFO logged 42 flights in Jan–Mar 2026 and 138 flights in Apr–Jun 2026. Fewer than three of those quarters carried the 30 completed flights this site needs before printing a rate, so the 60.7% annual figure is the one to use.
Delay causes
Why United runs late on this route
One category carries most of the weight here. National Airspace System accounts for 43% of the 6,013 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.
- 43%National Airspace System
- 43%Carrier
- 14%Late-arriving aircraft
The largest share of delay minutes, 43%, 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 2,597 of the 6,013 delay minutes reported here. The split is drawn from 6,013 reported delay minutes.
43% 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 2,603 minutes out of 6,013, against a national NAS share of 21%.
Cancellations sit at 1.11% against a national 1.81%, which is ordinary. Diversions add another 0.00%.
Connections and stage length
What a delay here costs
For anyone connecting, the number to weigh is not the on-time rate but the tail behind it. 15.2% of arrivals land a full hour or more behind schedule, against 8.1% nationally. A 45-minute layover does not survive that, and no amount of walking quickly changes it. Ninety minutes is the honest minimum here, and two hours if the onward flight is on a separate ticket.
At 191 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 70.9% on time across 181 flights, 10 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 10 points of difference.
One caution: this is a thin sample. 180 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 United on SBP to SFO
Put together: treat all of this as provisional. 180 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 60.7% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 178 completed flights over 12 months sit behind that.
Related
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.