Airport month record

LASMAY

Harry Reid International in May 2026

Departures: 14,585
Month: May 2026
National, same month: 78.6%
Carriers: 9

Historical statistics for May 2026, not live status or a forecast for this year’s May. For today’s conditions at LAS, see live FAA status.

LAS in May sits in the middle of the pack with a C+. Close to three flights in four arrive on time by the DOT's definition, 5 points worse than the national rate of 78.6%. The late ones land about an hour behind schedule. That rests on 14,585 flights, of which American Airlines flew 1,314 at 84.1% on time.

American Airlines is the most reliable of the eight carriers covered here at 84.1% on time across 1,314 flights.

On time

74.1%

Arrivals under 15 minutes late, of 14,454 completed departures

Avg delay

60 min

Across delayed arrivals only, not all flights

Cancelled

0.67%

Nationally in May: 0.92%

Whole year

77.9%

LAS across all twelve months

These figures cover 14,585 departures from Harry Reid International in May 2026. On time means an arrival less than 15 minutes after the scheduled gate time, the DOT's threshold, and the national comparison uses every US departure in the same month rather than the whole year.

Against the year

May next to LAS's other months

Against LAS's own year, May ran 4 points worse than the twelve-month rate of 77.9%, which makes it number ten of twelve months, best first. Either side of it, April ran 78.8% on time and June 70.7%, so this month sits in line with its neighbours.

LAS month by month
Month	Flights	On time	Avg delay	Cancelled	Grade
July 2025	15,733	72.9%	67 min	1.13%	C
August 2025	14,920	79.6%	59 min	0.50%	B+
September 2025	14,399	78.8%	66 min	0.53%	B+
October 2025	15,597	77.1%	62 min	0.31%	B+
November 2025	14,443	79.5%	59 min	1.73%	B
December 2025	14,547	79.9%	59 min	0.60%	B+
January 2026	13,695	83.1%	65 min	1.86%	B
February 2026	12,886	83.1%	58 min	0.88%	B+
March 2026	15,169	78.3%	60 min	1.15%	B
April 2026	14,672	78.8%	54 min	0.40%	B+
May 2026 (this page)	14,585	74.1%	60 min	0.67%	C+
June 2026	13,704	70.7%	61 min	0.77%	C+

Departure window

The best time of day to leave LAS in May

Departure time matters more here than the choice of carrier. The gap between the best and worst window is 29 points, against 15 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.

5am–8am2,342 flights90.2%
8am–11am2,798 flights82.8%
11am–2pm2,564 flights74.9%
2pm–5pm2,586 flights62.9%
5pm–8pm1,845 flights61.7%
8pm–5am2,450 flights68.8%

Scale runs 55% to 95%. Rows with fewer than 30 flights show a dash.

The 5pm–8pm window is where this operation falls apart: 61.7% on time, against 90.2% for the 5am–8am slot. By evening the aircraft flying these rotations have absorbed a full day of small delays and there is no slack left to recover in. The 8am–11am window is the busiest, with 2,798 flights scheduled in it.

Across the week, Saturday is the strongest day at 87.1% on time and Monday the weakest at 62.4%. 25 points is a smaller lever than departure hour, but it is free.

Carrier by carrier

Which airlines ran best at LAS in May

The choice of carrier is not cosmetic here. American Airlines arrives on time 84.1% of the time; Southwest Airlines manages 69.0%. Sample sizes sit next to every figure, because a two-point gap across 7,611 flights means less than a ten-point one.

Carriers at LAS in May 2026
Airline	Flights	On time	Avg delay	Cancelled	Grade
Southwest Airlines	7,611	69.0%	49 min	0.51%	C+
Delta Air Lines	1,382	81.8%	76 min	1.30%	B
American Airlines	1,314	84.1%	102 min	1.14%	B
United Airlines	1,295	77.2%	69 min	0.46%	B+
Frontier Airlines	1,159	77.2%	71 min	0.43%	B+
Alaska Airlines	642	77.2%	54 min	0.78%	B+
Allegiant Air	569	77.0%	75 min	0.00%	B+
JetBlue Airways	381	82.6%	103 min	0.26%	B+
SkyWest Airlinesthin sample	215	77.1%	93 min	0.47%	B+

The spread between American and Southwest is 15 points, wide enough that it should decide the booking. On a hundred trips that is 15 more arrivals inside the on-time window.

Route by route

Busiest routes out of LAS in May

Routes from LAS in May 2026
Route	Flights	On time	Avg delay	Cancelled	Grade
LAS to LAX · Los Angeles	650	74.6%	73 min	0.62%	C+
LAS to DEN · Denver	640	74.8%	56 min	0.94%	C+
LAS to PHX · Phoenix	547	78.2%	76 min	0.18%	B+
LAS to SFO · San Francisco	534	40.4%	61 min	0.75%	F+
LAS to SEA · Seattle	496	80.5%	49 min	0.81%	B+
LAS to ORD · Chicago	483	79.0%	68 min	0.00%	B+
LAS to DFW · Dallas-Fort Worth	455	83.5%	86 min	3.30%	B−
LAS to ATL · Atlanta	407	82.0%	78 min	0.25%	B+
LAS to SAN · San Diego	404	58.4%	63 min	0.74%	D+
LAS to SMF · Sacramentothin sample	332	71.0%	50 min	1.20%	C
LAS to JFK · New Yorkthin sample	329	86.3%	105 min	1.82%	A
LAS to RNO · Renothin sample	316	78.9%	48 min	0.95%	B+
LAS to SLC · Salt Lake Citythin sample	315	77.1%	60 min	0.32%	B+
LAS to SNA · Santa Anathin sample	305	78.9%	57 min	0.33%	B+
LAS to SJC · San Josethin sample	304	73.3%	46 min	0.33%	C+
LAS to BUR · Burbankthin sample	296	76.9%	44 min	0.68%	B+
LAS to OAK · Oaklandthin sample	284	61.9%	54 min	1.06%	D
LAS to EWR · Newarkthin sample	270	89.1%	92 min	0.37%	A+
LAS to IAH · Houstonthin sample	264	82.0%	87 min	0.76%	B+
LAS to DAL · Dallasthin sample	259	61.9%	61 min	1.54%	D
LAS to AUS · Austinthin sample	249	66.0%	49 min	0.40%	C+
LAS to PDX · Portlandthin sample	237	78.4%	53 min	0.42%	B+
LAS to DTW · Detroitthin sample	216	80.5%	60 min	2.31%	B
LAS to HNL · Honoluluthin sample	206	81.9%	45 min	0.97%	B+
LAS to MDW · Chicagothin sample	200	72.7%	44 min	0.50%	C+

Delay causes

What held LAS up in May

One category carries most of the weight here. Late-arriving aircraft accounts for 46% of the 223,000 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
46%
Carrier
35%
National Airspace System
17%
Extreme weather
2%
Security
0%

46% 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 223,000 reported delay minutes here, that single category outweighs weather by 24 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 223,497 reported delay minutes.

Cancellations are rare at 0.67%, below the national 0.92% 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.

7.5% of arrivals land an hour or more late, close to the national 7.1%. 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 last about an hour, which a normal layover absorbs.

What to do with this

Flying from LAS in May

For a May trip through LAS: plan on this being one of the airport's harder months. The 5am–8am departures held up best at 90.2% on time, and with 7.5% of arrivals an hour or more late, a connection here deserves more slack than the same trip in January would.

Harry Reid International (LAS), the whole year
LAS in July72.9%
LAS in August79.6%
LAS in September78.8%
LAS in October77.1%
LAS in November79.5%
LAS in December79.9%
LAS in January83.1%
LAS in February83.1%
LAS in March78.3%
LAS in April78.8%
LAS in June70.7%

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.

Key figures