Carrier performance at one airport
UA→LAS
United Airlines at Harry Reid International
- Departures
- 15,192
- Period
- June 2025 to May 2026
- Routes
- 7
- Rank here
- #5 of 11
United Airlines at Las Vegas lands a B+, 4 points better than the national rate of 77.4%. About one flight in five arrive 15 minutes late or worse, and those flights are late by about an hour on average. That is a workable record, not a spotless one. That rests on 15,192 flights, of which Delta Air Lines flew 15,922 at 85.0% on time.
Measured against the airport rather than the country, United Airlines runs 3 points ahead of the 78.2% weighted average across all carriers at LAS. That is the comparison worth making: every operator here works the same runways, the same airspace and the same weather.
Key figures
On time
81.1%
15,035 completed departures
Avg delay
67 min
Across delayed flights only
Cancelled
0.68%
At LAS, this carrier only
Rank here
#5
Of 11 carriers clearing the floor at LAS
These figures cover 15,000 flights between June 2025 and May 2026. The median arrival is 9 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.
Against the competition
Every carrier at LAS, ranked
The choice of carrier is not cosmetic here. Delta Air Lines arrives on time 85.0% of the time; Hawaiian Airlines manages 67.9%. Sample sizes sit next to every figure, because a two-point gap across 976 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Delta Air Lines | 15,922 | 85.0% | 77 min | 1.06% | A |
| Allegiant Air | 7,221 | 83.8% | 73 min | 0.43% | B+ |
| Spirit Airlines | 10,027 | 81.9% | 71 min | 1.34% | B |
| American Airlines | 14,112 | 81.2% | 98 min | 1.82% | B |
| United Airlines (this page) | 15,192 | 81.1% | 67 min | 0.68% | B+ |
| SkyWest Airlines | 4,083 | 79.9% | 70 min | 0.96% | B+ |
| Alaska Airlines | 6,643 | 79.3% | 59 min | 1.05% | B |
| JetBlue Airways | 3,865 | 78.1% | 80 min | 1.89% | B |
| Frontier Airlines | 12,015 | 77.5% | 76 min | 1.29% | B |
| Southwest Airlines | 86,362 | 75.1% | 50 min | 0.58% | B+ |
| Hawaiian Airlines | 976 | 67.9% | 77 min | 0.51% | C+ |
The spread between Delta and Hawaiian is 17 points, wide enough that it should decide the booking. On a hundred trips that is 17 more arrivals inside the on-time window.
Route by route
Where United Airlines flies from LAS
United Airlines operates 7 routes out of LAS with enough volume to report. Route records inside one carrier at one airport still spread widely, because a short shuttle and a transcontinental have very different exposure to a late inbound.
| Route | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| LAS to SFO · San Francisco | 2,733 | 70.6% | 59 min | 0.44% | C+ |
| LAS to IAH · Houston | 2,606 | 85.2% | 73 min | 0.73% | A+ |
| LAS to EWR · Newark | 2,464 | 81.6% | 83 min | 1.38% | B |
| LAS to DEN · Denver | 2,454 | 82.8% | 67 min | 0.49% | B+ |
| LAS to ORD · Chicago | 2,332 | 80.0% | 68 min | 0.43% | B+ |
| LAS to LAX · Los Angeles | 1,562 | 86.2% | 55 min | 0.70% | A+ |
| LAS to IAD · Washington | 1,037 | 88.4% | 51 min | 0.58% | A+ |
Departure window
Best time of day for this operation
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 18 points, against 17 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am2,535 flights91.3%
- 8am–11am3,102 flights87.1%
- 11am–2pm3,110 flights75.2%
- 2pm–5pm2,869 flights74.1%
- 5pm–8pm1,538 flights73.1%
- 8pm–5am2,038 flights84.2%
Scale runs 65% to 95%. Rows with fewer than 30 flights show a dash.
Book the early departure. Flights leaving between 5am–8am arrive on time 91.3% of the time, against 73.1% for the evening window. That is 18 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on.
Across the year
Seasonal pattern
July is the worst month at 75.1% on time, 12 points below February, the best at 87.5%. Summer afternoon convection and peak-season schedules land on the same weeks every year, so this is a pattern you can book around rather than a run of bad luck.
Delay causes
What holds this operation up
- 46%National Airspace System
- 34%Late-arriving aircraft
- 18%Carrier
- 2%Extreme weather
46% of delay minutes are charged to the National Airspace System: air traffic volume, runway configuration, ground stops. No carrier can price its way out of that, which is why airport choice moves the number here more than carrier choice does. That is 87,000 minutes out of 189,000, against a national NAS share of 21%.
Cancellations are rare at 0.68%, below the national 1.80% 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.
6.7% of arrivals land an hour or more late, close to the national 8.2%. 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 are the about an hour kind, which a normal layover absorbs.
15,192 flights sit behind these numbers, which is a large enough sample that the headline rate is not moving on noise. Where a sub-group falls below 30 flights the site shows a dash instead of a percentage.
Put together: the calendar is the biggest lever here, not the carrier or the hour. February runs 87.5% on time and July 75.1%, a swing of 12 points. If the dates move at all, move them out of July before you think about anything else.
Common questions
United Airlines at LAS
How often is United Airlines at LAS delayed?
About one flight in five arrive at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 18.9% of the 15,192 flights in this analysis, against 22.6% nationally. Delayed flights are late by about an hour on average.
Which airline is most reliable on United Airlines at LAS?
Delta Air Lines leads at 85.0% on time across 15,922 flights. Hawaiian Airlines is at the other end on 67.9%, a gap of 17 points. Sample size matters as much as the percentage: a rate built from a few hundred flights moves around far more than one built from ten thousand.
What time of day has the fewest delays on United Airlines at LAS?
The 5am–8am departure window is the strongest at 91.3% on time. The 5pm–8pm window is the weakest at 73.1%, 18 points behind. Later departures inherit delays from earlier flights the same aircraft has already flown, which is why the curve slopes the way it does.
How bad are July delays on United Airlines at LAS?
July is the weakest month at 75.1% on time, compared with 87.5% in February. Across the year that is 12 points between the best and worst months. Moving flexible dates out of that month is one of the few things that reliably helps.
Related
Where to go next
Source: US DOT Bureau of Transportation Statistics, on-time performance data, June 2025 to May 2026. Updated monthly. How this data is collected.