Flight number record
UA 1924
United Airlines · Denver to Washington
- Route
- DEN → IAD
- Departs
- 23:59
- Flights
- 341
- Period
- September 2025 to August 2026
Historical statistics for September 2025 to August 2026, not live status. For today’s UA 1924, check with United Airlines.
UA 1924 earns an A+. Nearly every flight arrives inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 17 points better than the national rate of 77.3%. When something does go wrong the average delay runs a little over an hour. That rests on 341 flights, with a median arrival 17 minutes early.
Set against the rest of the country, UA 1924's record is 17 points better than the US average of 77.3%. That gap is worth roughly 165 fewer late arrivals for every thousand flights.
Key figures
On time
93.8%
Arrivals under 15 minutes late, of 339 completed flights
Avg delay
69 min
Across delayed arrivals only, not all flights
Cancelled
0.59%
National rate is 1.89%
1 hour+ late
2.1%
National rate is 8.3%
These figures cover 341 flights between September 2025 and August 2026. The median arrival is 17 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.
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Schedule
When UA 1924 flies
UA 1924 is scheduled to leave Denver (DEN) at 23:59 local time and reach Washington (IAD) at 05:27. That slot held for 341 of the 341 scheduled departures in the data, so the figures below describe one steady operation rather than a number that moved around the clock.
- Departs 23:59341 flights100.0%
Scale runs 0% to 100%.
Share of scheduled departures at each local time. Times used on fewer than one flight in ten are not listed.
A 23:59 departure sits in the 8pm–5am window. Across every US flight scheduled in that window the on-time rate is 70.1%, and UA 1924 runs 24 points better at 93.8%. By that time of day most aircraft have flown several legs already, and whatever went wrong earlier is still in the schedule.
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Against the route
UA 1924 next to DEN to IAD
Every carrier on DEN to IAD combined arrived on time 81.8% of the time across 3,385 flights, so UA 1924 is 12 points ahead of it. United flew 2,790 flights on the same city pair under all its flight numbers, including this one, and those ran 84.8% on time. Across its whole network United Airlines managed 78.8%, which this flight beats by 15 points.
| Compared with | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| UA 1924thin sample | 341 | 93.8% | 69 min | 0.59% | A+ |
| All United Airlines on DEN–IAD | 2,790 | 84.8% | 66 min | 0.50% | B+ |
| All carriers on DEN–IAD | 3,385 | 81.8% | 60 min | 0.59% | B+ |
| United Airlines, whole network | 830,825 | 78.8% | 73 min | 1.02% | B |
Across the year
UA 1924 quarter by quarter
UA 1924 did not run the same all year. Its best quarter was Oct–Dec 2025 at 98.9% on time and its weakest Jul–Sep 2026 at 83.9%, a swing of 15 points on roughly 68 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 202530 flights93.3%
- Oct–Dec 202587 flights98.9%
- Jan–Mar 202680 flights93.6%
- Apr–Jun 202682 flights96.3%
- Jul–Sep 202662 flights83.9%
Scale runs 75% to 100%.
By weekday, UA 1924 ranged from 86.8% on Monday to 97.9% on Wednesday. With about 49 flights behind each day, a spread of 11 points is inside normal variation, so the day you fly is not worth changing for this flight.
Arrival by arrival
How late UA 1924 runs when it is late
UA 1924 often beats the schedule: 195 of 339 completed flights, 58%, arrived 15 minutes or more early. The 21 late arrivals split 8 under half an hour, 6 between 30 and 60 minutes, and 7 an hour or more.
- 15+ min early195 flights57.5%
- Within 15 min123 flights36.3%
- 15–29 min late8 flights2.4%
- 30–59 min late6 flights1.8%
- 1–2 hours late6 flights1.8%
- 2+ hours late1 flights0.3%
Scale runs 0% to 100%.
Share of 339 completed flights by arrival against schedule.
A late pushback is often recovered here: of 28 departures that left 15 minutes late or more, 11 still arrived on time. Only 4 left on time and still arrived late.
The worst days
Worst days for UA 1924
The latest arrival of the period was on 27 July 2026, 8 hours 1 minute behind schedule; most of its delay minutes were filed as carrier-caused (crew, maintenance, fuelling, baggage). The same cause led on four of the five worst days.
| Date | Arrived late by | Largest filed cause |
|---|---|---|
| 27 July 2026 | 8 hours 1 minute | Carrier |
| 6 March 2026 | 1 hour 58 minutes | Carrier |
| 22 September 2025 | 1 hour 49 minutes | Carrier |
| 14 August 2026 | 1 hour 27 minutes | Late-arriving aircraft |
| 21 June 2026 | 1 hour 26 minutes | Carrier |
Delay causes
Why UA 1924 runs late
Carrier accounts for 71% of the 1,450 delay minutes carriers reported here, and the remaining four split what is left.
- 71%Carrier
- 19%Late-arriving aircraft
- 11%National Airspace System
The largest share of delay minutes, 71%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. It accounts for 1,025 of the 1,450 delay minutes reported here. The split is drawn from 1,450 delay minutes reported on UA 1924.
Cancellations are rare at 0.59%, below the national 1.89% 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
Badly late arrivals are rare here: only 2.1% land an hour or more behind schedule, against 8.3% nationally. Connections built on this flight are about as safe as US domestic connections get, though a cancelled flight still ignores every layover you give it.
The 1,452 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.
The same number turns up on four other city pairs in the data, including DFW to DEN (36), SBA to DEN (35) and SJC to DEN (15), but none flew often enough under UA 1924 to report a rate for. Carriers move flight numbers between routes, so the figures on this page apply to DEN to IAD only.
One caution: this is a thin sample. 341 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 1924
For a booking, UA 1924 has one of the better records a US domestic flight can show: 93.8% on time and 0.59% cancelled. That is a base rate, not a promise about any single day.
Related
Where to go next
- DEN to IAD, every carrier and departure
- IAD to DEN, the return direction
- United Airlines 2408 on the same route71.6%
- United Airlines 2087 on the same route81.4%
- United Airlines 347 on the same route87.0%
- United Airlines 1101 on the same route93.8%
- Denver International (DEN) delay statistics
- Washington Dulles International (IAD) 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, September 2025 to August 2026. Last updated ; recomputed monthly. How this data is collected.