Carrier route record
UASBP→DEN
United Airlines · San Luis Obispo to Denver
- 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 SBP to DEN lands a B+, 6 points better than the national rate of 77.6%. About one flight in six arrives 15 minutes late or worse, and those flights are late by about 2.5 hours on average. That is a workable record, not a spotless one. That rests on 403 flights, with a median arrival 7 minutes early.
Set against the rest of the country, United's SBP to DEN record is 6 points better than the US average of 77.6%. That gap is worth roughly 62 fewer late arrivals for every thousand flights.
Key figures
On time
83.8%
Arrivals under 15 minutes late, of 396 completed flights
Avg delay
148 min
Across delayed arrivals only, not all flights
Cancelled
0.74%
National rate is 1.81%
Whole route
81.2%
Every carrier on SBP to DEN, 724 flights
These figures cover 403 flights between July 2025 and June 2026. Beyond the headline rate, 8.3% 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 DEN
United flew 403 of the 724 flights on SBP to DEN, most of the route. Its 83.8% on time is 3 points better than the route as a whole, which runs 81.2%. Ranked by on-time rate it is first of two carriers on the route, where the range runs from United at 83.8% to SkyWest at 78.0%. 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 |
|---|---|---|---|---|---|
| United Airlines (this page) | 403 | 83.8% | 148 min | 0.74% | B+ |
| SkyWest Airlinesthin sample | 321 | 78.0% | 92 min | 0.00% | B+ |
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 22 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–8am361 flights86.0%
- 8am–11am1 flights—
- 11am–2pm41 flights64.1%
- 2pm–5pm—
- 5pm–8pm—
- 8pm–5am—
Scale runs 55% to 90%. 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 64.1% on time against 86.0% for 5am–8am. 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 5am–8am window is the busiest, with 361 flights scheduled in it.
Across the year
United on SBP to DEN through the year
December is the weak month at 76.7% on time, against 96.8% in October. 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. June was the busiest month here, with 60 flights.
Across the week, Thursday is the strongest day at 92.9% on time and Friday the weakest at 76.8%. 16 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 9,437 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
- 38%Carrier
- 9%National Airspace System
- 1%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 9,437 reported delay minutes here, that single category outweighs weather by 35 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 9,437 reported delay minutes.
The largest share of delay minutes, 38%, 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 3,628 of the 9,437 delay minutes reported here.
Cancellations are rare at 0.74%, 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
8.3% 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 about 2.5 hours, which a normal layover absorbs.
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 76.1% on time across 403 flights, 8 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 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 SBP to DEN
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 83.8% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 396 completed flights over 12 months sit behind that.
Related
Where to go next
- SBP to DEN, every carrier
- United on DEN to SBP, the return leg
- SkyWest Airlines on SBP to DEN78.0%
- United Airlines network-wide record
- Denver International (DEN) delay statistics
- Why the first flight of the morning is statistically safest
- The best time of day to fly, according to 7.04 million flight records
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.