Flight number record
UA 2408
United Airlines · Denver to Washington
- Route
- DEN → IAD
- Departs
- 17:59
- Flights
- 363
- Period
- July 2025 to June 2026
Historical statistics for July 2025 to June 2026, not live status. For today’s UA 2408, check with United Airlines.
UA 2408 sits in the middle of the pack with a C+. About seven flights in ten arrive on time by the DOT's definition, 9 points worse than the national rate of 77.6%. The late ones land a little over an hour behind schedule. That rests on 363 flights, with a median arrival 1 minute late.
The national on-time rate over the same period is 77.6%, so UA 2408 runs 9 points behind the country as a whole. Across a thousand flights that is about 90 extra late arrivals.
Key figures
On time
68.6%
Arrivals under 15 minutes late, of 360 completed flights
Avg delay
78 min
Across delayed arrivals only, not all flights
Cancelled
0.83%
National rate is 1.81%
1 hour+ late
10.8%
National rate is 8.1%
These figures cover 363 flights between July 2025 and June 2026. Beyond the headline rate, 10.8% 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.
Schedule
When UA 2408 flies
UA 2408 flies DEN to IAD without a single fixed slot. Its most common scheduled departure was 17:59, used on 114 of 363 flights, with 18:00 (60 flights) and 17:56 (51 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.
- Departs 17:59114 flights31.4%
- Departs 18:0060 flights16.5%
- Departs 17:5651 flights14.0%
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 17:59 departure sits in the 5pm–8pm window. Across every US flight scheduled in that window the on-time rate is 68.2%, and UA 2408 runs level with that at 68.6%. By that time of day most aircraft have flown several legs already, and whatever went wrong earlier is still in the schedule.
Against the route
UA 2408 next to DEN to IAD
Every carrier on DEN to IAD combined arrived on time 80.3% of the time across 3,558 flights, so UA 2408 is 12 points behind it. United flew 2,797 flights on the same city pair under all its flight numbers, including this one, and those ran 84.4% on time. Across its whole network United Airlines managed 79.0%, which this flight trails by 10 points.
| Compared with | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| UA 2408thin sample | 363 | 68.6% | 78 min | 0.83% | C+ |
| All United Airlines on DEN–IAD | 2,797 | 84.4% | 70 min | 0.46% | B+ |
| All carriers on DEN–IAD | 3,558 | 80.3% | 64 min | 0.56% | B+ |
| United Airlines, whole network | 821,041 | 79.0% | 72 min | 1.01% | B |
Across the year
UA 2408 quarter by quarter
UA 2408 did not run the same all year. Its best quarter was Jan–Mar 2026 at 80.7% on time and its weakest Jul–Sep 2025 at 41.8%, a swing of 39 points on roughly 91 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 flights41.8%
- Oct–Dec 202590 flights80.0%
- Jan–Mar 202690 flights80.7%
- Apr–Jun 202691 flights72.5%
Scale runs 35% to 85%. Rows with fewer than 30 flights show a dash.
By weekday, UA 2408 ranged from 62.7% on Thursday to 72.0% on Friday. With about 52 flights behind each day, a spread of 9 points is inside normal variation, so the day you fly is not worth changing for this flight.
Delay causes
Why UA 2408 runs late
One category carries most of the weight here. Late-arriving aircraft accounts for 44% of the 8,796 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.
- 44%Late-arriving aircraft
- 33%Carrier
- 19%National Airspace System
- 4%Security
- 0%Extreme weather
44% 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 8,796 reported delay minutes here, that single category outweighs weather by 44 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 8,796 delay minutes reported on UA 2408.
Cancellations are rare at 0.83%, 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
For anyone connecting, the number to weigh is not the on-time rate but the tail behind it. 10.8% 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 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. 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 one other city pair in the data, including SFO to BZN (2), but none flew often enough under UA 2408 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. 363 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 2408
For a booking, UA 2408 is one of the weaker ways to fly DEN to IAD: 12 points below the route as a whole. If the schedule allows, compare it with the other departures listed on the route page before settling on this one.
Related
Where to go next
- DEN to IAD, every carrier and departure
- IAD to DEN, the return direction
- United Airlines 2087 on the same route80.1%
- United Airlines 1924 on the same route93.5%
- United Airlines 347 on the same route86.8%
- United Airlines 798 on the same route83.0%
- United Airlines 1101 on the same route94.5%
- 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
- Why the first flight of the morning is statistically safest
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.