Las Vegas, NV · departure reliability

LAS

Harry Reid International

Departures: 176,428
Period: June 2025 to May 2026
Carriers: 11
US rank: #8 by volume

Terminal building and aircraft stands at a US airport

Las Vegas

Harry Reid International lands a B+, about a point better than the national rate of 77.4%. Roughly 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 176,428 flights, of which Delta Air Lines flew 15,922 at 85.0% on time.

Delta Air Lines is the most reliable of the eleven carriers covered here at 85.0% on time across 15,922 flights.

On time

78.2%

Departures arriving under 15 minutes late at their destination

Avg delay

61 min

Across delayed flights only

Cancelled

0.87%

National rate is 1.80%

Best carrier

Delta

85.0% on time here

These figures cover 176,000 flights between June 2025 and May 2026. The median arrival is 6 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.

Carrier by carrier

Which airlines run best out of LAS

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.

On-time performance by carrier departing LAS
Airline	Flights	On time	Avg delay	Cancelled	Grade
Southwest Airlines	86,362	75.1%	50 min	0.58%	B+
Delta Air Lines	15,922	85.0%	77 min	1.06%	A
United Airlines	15,192	81.1%	67 min	0.68%	B+
American Airlines	14,112	81.2%	98 min	1.82%	B
Frontier Airlines	12,015	77.5%	76 min	1.29%	B
Spirit Airlines	10,027	81.9%	71 min	1.34%	B
Allegiant Air	7,221	83.8%	73 min	0.43%	B+
Alaska Airlines	6,643	79.3%	59 min	1.05%	B
SkyWest Airlines	4,083	79.9%	70 min	0.96%	B+
JetBlue Airways	3,865	78.1%	80 min	1.89%	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

Busiest routes out of LAS

Route-level records vary far more than the airport average. These are the 25 busiest departures from LAS, each with its own on-time rate against the airport-wide 78.2%.

Busiest routes from LAS by flight volume
Route	Flights	On time	Avg delay	Cancelled	Grade
LAS to LAX · Los Angeles	8,424	78.7%	61 min	0.68%	B+
LAS to DEN · Denver	7,060	76.6%	65 min	0.85%	B+
LAS to SAN · San Diego	6,131	67.7%	56 min	1.09%	C
LAS to PHX · Phoenix	6,060	78.4%	66 min	1.06%	B
LAS to SFO · San Francisco	6,044	65.8%	57 min	0.73%	C+
LAS to SEA · Seattle	5,699	82.0%	61 min	1.02%	B
LAS to ORD · Chicago	5,368	76.7%	77 min	1.14%	B
LAS to DFW · Dallas-Fort Worth	5,242	80.6%	96 min	2.79%	B
LAS to ATL · Atlanta	4,840	84.2%	73 min	1.10%	B
LAS to SNA · Santa Ana	4,387	82.2%	55 min	0.68%	B+
LAS to SMF · Sacramento	4,381	78.6%	58 min	0.57%	B+
LAS to BUR · Burbank	4,278	79.9%	57 min	1.40%	B
LAS to RNO · Reno	3,975	80.0%	57 min	0.68%	B+
LAS to SJC · San Jose	3,944	78.8%	55 min	0.38%	B+
LAS to SLC · Salt Lake City	3,754	82.8%	62 min	0.72%	B+
LAS to JFK · New York	3,716	80.0%	89 min	2.42%	B
LAS to IAH · Houston	3,483	83.2%	75 min	0.98%	B+
LAS to OAK · Oakland	3,407	72.7%	53 min	0.47%	C+
LAS to PDX · Portland	3,029	79.3%	56 min	0.53%	B+
LAS to EWR · Newark	2,998	81.1%	79 min	1.60%	B
LAS to DTW · Detroit	2,941	81.7%	72 min	0.58%	B+
LAS to DAL · Dallas	2,877	72.9%	50 min	1.60%	C
LAS to AUS · Austin	2,868	74.1%	55 min	0.42%	C+
LAS to ONT · Ontario	2,484	76.4%	57 min	0.76%	B+
LAS to MDW · Chicago	2,397	77.7%	48 min	0.88%	B+

Departure window

The best time of day to leave LAS

Departure time matters more here than the choice of carrier. The gap between the best and worst window is 23 points, against 17 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.

5am–8am26,961 flights91.9%
8am–11am37,046 flights84.2%
11am–2pm30,464 flights77.1%
2pm–5pm28,771 flights70.9%
5pm–8pm25,036 flights69.2%
8pm–5am28,150 flights73.7%

Scale runs 60% to 95%. Rows with fewer than 30 flights show a dash.

Book the early departure. Flights leaving between 5am–8am arrive on time 91.9% of the time, against 69.2% for the evening window. That is 23 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

When LAS runs late

Twelve months, one bar each, drawn from the same 176,428 flights. The strip shows how much of LAS's record is set by the calendar rather than by the operation.

Darker means more delays. Figures are on-time percentages.January best, July worst

July is the worst month at 72.9% on time, 10 points below January, the best at 83.1%. 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.

Across the week, Saturday is the strongest day at 84.4% on time and Sunday the weakest at 74.3%. 10 points is a smaller lever than departure hour, but it is free.

Delay causes

Why LAS gets delayed

One category carries most of the weight here. Late-arriving aircraft accounts for 44% of the 2.33 million 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.

Late-arriving aircraft
44%
Carrier
34%
National Airspace System
19%
Extreme weather
2%
Security
0%

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 2.33 million reported delay minutes here, that single category outweighs weather by 18 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 largest share of delay minutes, 34%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. Unlike weather, that is a management outcome, and it is the category where the gap between two carriers on the same schedule is genuinely earned. It accounts for 804,000 of the 2.33 million delay minutes reported here.

Cancellations are rare at 0.87%, 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.

6.5% 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.

176,428 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.

What to do with this

Flying out of LAS

Put together: avoid the 5pm–8pm departure. It runs 69.2% on time against 91.9% for the 5am–8am slot, and that 23 points is the largest single thing you control here. Delta Air Lines is the strongest operator if the fares are close.

Common questions

LAS delay questions

How often is Las Vegas (LAS) delayed?

Roughly 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 21.8% of the 176,428 flights in this analysis, against 22.6% nationally. Delayed flights are late by about an hour on average.

Which airline is most reliable on Las Vegas (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 Las Vegas (LAS)?

The 5am–8am departure window is the strongest at 91.9% on time. The 5pm–8pm window is the weakest at 69.2%, 23 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 Las Vegas (LAS)?

July is the weakest month at 72.9% on time, compared with 83.1% in January. Across the year that is 10 points between the best and worst months. Moving flexible dates out of that month is one of the few things that reliably helps.

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.

Key figures