Carrier route record
UADEN→SBP
United Airlines · Denver to San Luis Obispo
- Flights
- 403
- Period
- July 2025 to June 2026
- Share of route
- 56%
- Carriers
- 2
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with United Airlines.
United on DEN to SBP lands a B+, 2 points worse than the national rate of 77.6%. About one flight in four arrives 15 minutes late or worse, and those flights are late by close to two hours on average. That is a workable record, not a spotless one. That rests on 403 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 United on DEN to SBP from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.
Key figures
On time
76.1%
Arrivals under 15 minutes late, of 394 completed flights
Avg delay
104 min
Across delayed arrivals only, not all flights
Cancelled
0.50%
National rate is 1.81%
Whole route
76.8%
Every carrier on DEN to SBP, 724 flights
These figures cover 403 flights between July 2025 and June 2026. Beyond the headline rate, 10.2% 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 DEN to SBP
United flew 403 of the 724 flights on DEN to SBP, most of the route. Its 76.1% on time is about level with the route as a whole at 76.8%. Ranked by on-time rate it is last of two carriers on the route, where the range runs from SkyWest at 77.6% to United at 76.1%. One 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 |
|---|---|---|---|---|---|
| SkyWest Airlinesthin sample | 321 | 77.6% | 48 min | 0.00% | B+ |
| United Airlines (this page) | 403 | 76.1% | 104 min | 0.50% | B+ |
Flight by flight
United flight numbers on DEN to SBP
Departure window
When United 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 403 flights.
- 5am–8am—
- 8am–11am—
- 11am–2pm41 flights68.3%
- 2pm–5pm25 flights—
- 5pm–8pm337 flights76.5%
- 8pm–5am—
Scale runs 60% to 80%. Rows with fewer than 30 flights show a dash.
The weak window here is the middle of the day, not the evening: 11am–2pm runs 68.3% on time against 76.5% for 5pm–8pm. That shape usually means a departure bank rather than an accumulating delay, so the recovery later in the afternoon is real rather than noise. The 5pm–8pm window is the busiest, with 337 flights scheduled in it.
Across the year
United on DEN to SBP through the year
- Jul–Sep 202590 flights62.1%
- Oct–Dec 202591 flights87.4%
- Jan–Mar 202690 flights85.4%
- Apr–Jun 2026132 flights71.8%
Scale runs 55% to 95%. 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 76.1% on time across 403 flights.
United on DEN to SBP did not run the same all year. Its best quarter was Oct–Dec 2025 at 87.4% on time and its weakest Jul–Sep 2025 at 62.1%, a swing of 25 points on roughly 101 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, Monday is the strongest day at 83.6% on time and Sunday the weakest at 63.2%. 20 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 43% of the 9,791 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%Late-arriving aircraft
- 20%Extreme weather
- 19%National Airspace System
- 18%Carrier
Extreme weather accounts for 20% of delay minutes, well above the single-digit share typical across the system. Weather delays are lumpy: they arrive as whole bad days rather than as a steady drag, so the monthly strip above is the more useful view of the risk. The national share is 6%, so this operation carries roughly 3.2 times the usual weather exposure. The split is drawn from 9,791 reported delay minutes.
43% 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 9,791 reported delay minutes here, that single category outweighs weather by 2 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.
Cancellations are rare at 0.50%, 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
For anyone connecting, the number to weigh is not the on-time rate but the tail behind it. 10.2% 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.
The 931 miles between these two airports put this in the middle of the US network, around two and a half to three hours of block time. That is enough cruise to absorb a ten-minute late pushback and not enough to absorb thirty. It is also long enough that the aircraft usually flies three or four legs a day rather than six, which slows how fast delay compounds.
The return leg is a different operation and performs like one: it runs 83.8% on time across 403 flights, 8 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 8 points of difference.
One caution: this is a thin sample. 403 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 DEN to SBP
Put together: treat all of this as provisional. 403 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 76.1% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 394 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.