Flight number record
UA 581
United Airlines · Des Moines to Denver
- Route
- DSM → DEN
- Departs
- 09:00
- Flights
- 279
- Period
- July 2025 to June 2026
Historical statistics for July 2025 to June 2026, not live status. For today’s UA 581, check with United Airlines.
UA 581 lands a B+, 2 points 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 a little over an hour on average. That is a workable record, not a spotless one. That rests on 279 flights, with a median arrival right on schedule.
Key figures
On time
79.4%
Arrivals under 15 minutes late, of 277 completed flights
Avg delay
73 min
Across delayed arrivals only, not all flights
Cancelled
0.72%
National rate is 1.81%
1 hour+ late
6.9%
National rate is 8.1%
These figures cover 279 flights between July 2025 and June 2026. On-time means an arrival less than 15 minutes after the scheduled gate time, the same threshold the Department of Transportation uses in its own reports. Cancelled and diverted flights are excluded from the on-time rate and counted separately, which is why the cancellation column matters on its own.
Schedule
When UA 581 flies
UA 581 flies DSM to DEN without a single fixed slot. Its most common scheduled departure was 09:00, used on 67 of 279 flights, with 09:15 (49 flights) and 09:01 (37 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.
- Departs 09:0067 flights24.0%
- Departs 09:1549 flights17.6%
- Departs 09:0137 flights13.3%
Scale runs 0% to 100%. Rows with fewer than 30 flights show a dash.
Share of scheduled departures at each local time. Times used on fewer than one flight in ten are not listed.
A 09:00 departure sits in the 8am–11am window. Across every US flight scheduled in that window the on-time rate is 84.1%, and UA 581 runs 5 points worse at 79.4%. Early departures usually start with an aircraft that has not flown yet that day, which is most of why the window does well.
Against the route
UA 581 next to DSM to DEN
Every carrier on DSM to DEN combined arrived on time 83.0% of the time across 2,329 flights, so UA 581 is 4 points behind it. United flew 681 flights on the same city pair under all its flight numbers, including this one, and those ran 74.2% on time. Across its whole network United Airlines managed 79.0%, close to this flight's figure.
| Compared with | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| UA 581thin sample | 279 | 79.4% | 73 min | 0.72% | B+ |
| All United Airlines on DSM–DEN | 681 | 74.2% | 77 min | 0.59% | C+ |
| All carriers on DSM–DEN | 2,329 | 83.0% | 84 min | 0.60% | B+ |
| United Airlines, whole network | 821,041 | 79.0% | 72 min | 1.01% | B |
Across the year
UA 581 quarter by quarter
UA 581 did not run the same all year. Its best quarter was Jan–Mar 2026 at 83.1% on time and its weakest Jul–Sep 2025 at 72.8%, a swing of 10 points on roughly 93 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.
- Jul–Sep 202592 flights72.8%
- Oct–Dec 202592 flights82.4%
- Jan–Mar 202666 flights83.1%
- Apr–Jun 202629 flights—
Scale runs 65% to 90%. Rows with fewer than 30 flights show a dash.
By weekday, UA 581 did best on Sunday at 89.7% on time and worst on Wednesday at 73.2%. Each day rests on about 40 flights, so a gap of 17 points is worth noticing but could still narrow in another year.
Delay causes
Why UA 581 runs late
One category carries most of the weight here. Carrier accounts for 43% of the 4,164 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%Carrier
- 36%National Airspace System
- 14%Extreme weather
- 7%Late-arriving aircraft
Extreme weather accounts for 14% 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 quarterly figures above are the more useful view of the risk. The national share is 6%, so this operation carries roughly 2.3 times the usual weather exposure. The split is drawn from 4,164 delay minutes reported on UA 581.
Cancellations are rare at 0.72%, 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 routes
What a delay on this flight costs
6.9% 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 a little over an hour, which a normal layover absorbs.
The 589 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 same number turns up on seven other city pairs in the data, including BWI to ORD (35), ORD to DSM (33) and EWR to FLL (24), but none flew often enough under UA 581 to report a rate for. Carriers move flight numbers between routes, so the figures on this page apply to DSM to DEN only.
One caution: this is a thin sample. 279 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 UA 581
For a booking, read UA 581 as 79.4% on time with 0.72% cancelled over 279 flights. Those are rates from the past twelve months, not a forecast for any particular day.
Related
Where to go next
- DSM to DEN, every carrier and departure
- DEN to DSM, the return direction
- Denver International (DEN) delay statistics
- United Airlines on-time record
- Every United Airlines flight number with a record
- The most and least reliable flight numbers in the US
- Worst months to fly in the US, ranked by the data
A flight number here means United Airlines’s own number as it reports to the DOT. How the figures are computed is on the methodology page.
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.