Airport month record

HOUSEP

William P. Hobby in September 2025

Departures: 4,452
Month: September 2025
National, same month: 83.4%
Carriers: 3

Historical statistics for September 2025, not live status or a forecast for this year’s September. For today’s conditions at HOU, see live FAA status.

HOU in September earns an A+. More than four flights in five arrive inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 3 points better than the national rate of 83.4%. When something does go wrong the average delay runs about 45 minutes. That rests on 4,452 flights, with a median arrival 5 minutes early.

On time

86.1%

Arrivals under 15 minutes late, of 4,441 completed departures

Avg delay

45 min

Across delayed arrivals only, not all flights

Cancelled

0.11%

Nationally in September: 0.51%

Whole year

76.9%

HOU across all twelve months

These figures cover 4,452 departures from William P. Hobby in September 2025. 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

September next to HOU's other months

Against HOU's own year, September ran 9 points better than the twelve-month rate of 76.9%, which makes it number two of twelve months, best first. Cancellations were unusually low for HOU in September, at 0.11% against 0.84% across the year. Either side of it, August ran 78.2% on time and October 78.0%, so a trip moved by a few weeks would have landed in a worse stretch.

HOU month by month
Month	Flights	On time	Avg delay	Cancelled	Grade
July 2025	5,093	70.7%	59 min	0.79%	C+
August 2025	4,640	78.2%	56 min	0.37%	B+
September 2025 (this page)	4,452	86.1%	45 min	0.11%	A+
October 2025	4,887	78.0%	50 min	0.23%	B+
November 2025	4,552	80.1%	58 min	2.20%	B
December 2025	4,634	82.0%	49 min	0.43%	B+
January 2026	4,081	88.0%	44 min	2.55%	A
February 2026	3,832	84.2%	48 min	0.68%	B+
March 2026	4,578	67.5%	54 min	1.42%	C
April 2026	4,418	75.8%	50 min	0.14%	B+
May 2026	4,533	71.9%	51 min	0.79%	C+
June 2026	4,514	63.6%	56 min	0.62%	D+

Departure window

The best time of day to leave HOU in September

Departure time matters more here than the choice of carrier. The gap between the best and worst window is 18 points, against half a point between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.

5am–8am473 flights95.8%
8am–11am1,120 flights93.0%
11am–2pm759 flights86.2%
2pm–5pm662 flights82.8%
5pm–8pm832 flights79.5%
8pm–5am606 flights78.0%

Scale runs 70% to 100%. Rows with fewer than 30 flights show a dash.

Book the early departure. Flights leaving between 5am–8am arrive on time 95.8% of the time, against 78.0% for the overnight 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. The 8am–11am window is the busiest, with 1,120 flights scheduled in it.

Across the week, Tuesday is the strongest day at 92.7% on time and Wednesday the weakest at 81.6%. 11 points is a smaller lever than departure hour, but it is free.

Carrier by carrier

Which airlines ran best at HOU in September

Only one carrier clears this site's 365-flight floor here, so there is no comparison to draw. The table below is the full picture.

Carriers at HOU in September 2025
Airline	Flights	On time	Avg delay	Cancelled	Grade
Southwest Airlines	4,136	86.1%	43 min	0.07%	A+
Envoy Airthin sample	157	82.2%	81 min	0.00%	B+
Delta Air Linesthin sample	122	94.3%	26 min	0.00%	A+

Route by route

Busiest routes out of HOU in September

Routes from HOU in September 2025
Route	Flights	On time	Avg delay	Cancelled	Grade
HOU to DAL · Dallasthin sample	332	86.7%	43 min	0.00%	A+
HOU to ATL · Atlantathin sample	250	92.4%	35 min	0.00%	A+
HOU to DEN · Denverthin sample	188	76.6%	41 min	0.00%	B+
HOU to DFW · Dallas-Fort Worththin sample	186	79.3%	73 min	1.08%	B
HOU to MSY · New Orleansthin sample	176	91.5%	35 min	0.00%	A+
HOU to MDW · Chicagothin sample	163	88.9%	49 min	0.61%	A+
HOU to LAS · Las Vegasthin sample	155	83.2%	35 min	0.00%	B+
HOU to PHX · Phoenixthin sample	150	79.2%	46 min	0.67%	B+
HOU to SAT · San Antoniothin sample	141	92.2%	34 min	0.00%	A+
HOU to BNA · Nashvillethin sample	138	85.5%	40 min	0.00%	A+
HOU to MCO · Orlandothin sample	138	89.9%	60 min	0.00%	A+
HOU to AUS · Austinthin sample	136	85.3%	40 min	0.00%	A+
HOU to STL · St. Louisthin sample	125	88.0%	51 min	0.00%	A+
HOU to BWI · Baltimorethin sample	124	82.3%	45 min	0.00%	B+
HOU to HRL · Harlingenthin sample	112	89.3%	36 min	0.00%	A+
HOU to MAF · Midlandthin sample	108	93.5%	29 min	0.00%	A+
HOU to LGA · New Yorkthin sample	108	84.1%	44 min	0.00%	B+
HOU to OKC · Oklahoma Citythin sample	103	87.4%	40 min	0.00%	A+
HOU to LAX · Los Angelesthin sample	99	82.8%	44 min	0.00%	B+
HOU to DCA · Washingtonthin sample	86	77.6%	51 min	0.00%	B+
HOU to ELP · El Pasothin sample	81	86.4%	33 min	0.00%	A+
HOU to MCI · Kansas Citythin sample	77	80.5%	57 min	0.00%	B+
HOU to TPA · Tampathin sample	77	90.9%	58 min	0.00%	A+
HOU to ABQ · Albuquerquethin sample	77	84.4%	30 min	0.00%	B+
HOU to CRP · Corpus Christithin sample	77	84.4%	90 min	0.00%	B+

Delay causes

What held HOU up in September

One category carries most of the weight here. Late-arriving aircraft accounts for 44% of the 28,000 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
44%
Carrier
27%
National Airspace System
22%
Extreme weather
6%
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 28,000 reported delay minutes here, that single category outweighs weather by 7 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 27,735 reported delay minutes.

Cancellations are rare at 0.11%, below the national 0.51% 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.

Badly late arrivals are rare here: only 3.1% land an hour or more behind schedule, against 5.4% nationally. Connections built on this flight are about as safe as US domestic connections get, though a cancelled flight still ignores every layover you give it.

What to do with this

Flying from HOU in September

For a September trip through HOU: this is one of the better months to be flying from here, 86.1% on time with 0.11% cancelled. That is a base rate for the month as a whole; a single storm can still spoil a particular day.

Where to go next

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