Flight number record
UA 655
United Airlines · Denver to Las Vegas
- Route
- DEN → LAS
- Departs
- 19:40
- Flights
- 363
- Period
- July 2025 to June 2026
Historical statistics for July 2025 to June 2026, not live status. For today’s UA 655, check with United Airlines.
UA 655 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 early.
The national on-time rate over the same period is 77.6%, so UA 655 runs 9 points behind the country as a whole. Across a thousand flights that is about 92 extra late arrivals.
Key figures
On time
68.4%
Arrivals under 15 minutes late, of 361 completed flights
Avg delay
76 min
Across delayed arrivals only, not all flights
Cancelled
0.28%
National rate is 1.81%
1 hour+ late
12.5%
National rate is 8.1%
These figures cover 363 flights between July 2025 and June 2026. Beyond the headline rate, 12.5% 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 655 flies
UA 655 flies DEN to LAS without a single fixed slot. Its most common scheduled departure was 19:40, used on 69 of 363 flights, with 19:25 (68 flights) and 19:50 (42 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.
- Departs 19:4069 flights19.0%
- Departs 19:2568 flights18.7%
- Departs 19:5042 flights11.6%
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 19:40 departure sits in the 5pm–8pm window. Across every US flight scheduled in that window the on-time rate is 68.2%, and UA 655 runs level with that at 68.4%. 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 655 next to DEN to LAS
Every carrier on DEN to LAS combined arrived on time 75.3% of the time across 7,108 flights, so UA 655 is 7 points behind it. United flew 2,420 flights on the same city pair under all its flight numbers, including this one, and those ran 78.6% on time. Across its whole network United Airlines managed 79.0%, which this flight trails by 11 points.
| Compared with | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| UA 655thin sample | 363 | 68.4% | 76 min | 0.28% | C+ |
| All United Airlines on DEN–LAS | 2,420 | 78.6% | 66 min | 0.37% | B+ |
| All carriers on DEN–LAS | 7,108 | 75.3% | 63 min | 0.66% | B+ |
| United Airlines, whole network | 821,041 | 79.0% | 72 min | 1.01% | B |
Across the year
UA 655 quarter by quarter
UA 655 did not run the same all year. Its best quarter was Oct–Dec 2025 at 78.0% on time and its weakest Jul–Sep 2025 at 56.0%, a swing of 22 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 flights56.0%
- Oct–Dec 202591 flights78.0%
- Jan–Mar 202690 flights77.8%
- Apr–Jun 202690 flights61.8%
Scale runs 50% to 85%. Rows with fewer than 30 flights show a dash.
By weekday, UA 655 did best on Monday at 76.9% on time and worst on Thursday at 52.9%. Each day rests on about 52 flights, so a gap of 24 points is worth noticing but could still narrow in another year.
Delay causes
Why UA 655 runs late
One category carries most of the weight here. Late-arriving aircraft accounts for 54% of the 8,684 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.
- 54%Late-arriving aircraft
- 27%Carrier
- 19%National Airspace System
- 0%Extreme weather
54% 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 8,684 reported delay minutes here, that single category outweighs weather by 54 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 8,684 delay minutes reported on UA 655.
Cancellations are rare at 0.28%, 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. 12.5% 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 628 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 four other city pairs in the data, including LAS to EWR (43), SEA to DEN (30) and LAS to ORD (23), but none flew often enough under UA 655 to report a rate for. Carriers move flight numbers between routes, so the figures on this page apply to DEN to LAS 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 655
For a booking, UA 655 is a flight to put a long connection behind. 12.5% of its completed flights arrived an hour or more late, which a short layover will not absorb. If the onward flight is on a separate ticket, the risk sits with you.
Related
Where to go next
- DEN to LAS, every carrier and departure
- LAS to DEN, the return direction
- Frontier Airlines 777 on the same route73.5%
- United Airlines 2316 on the same route93.8%
- United Airlines 526 on the same route81.7%
- Frontier Airlines 1993 on the same route78.0%
- Frontier Airlines 2015 on the same route90.0%
- Denver International (DEN) delay statistics
- Harry Reid International (LAS) 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.