Houston, TX · departure reliability

HOU

William P. Hobby

Departures: 54,214
Period: July 2025 to June 2026
Carriers: 5
US rank: #37 by volume

Terminal building and aircraft stands at a US airport

Houston

William P. Hobby lands a B+, level with the national rate of 77.6%. Roughly one flight in four arrive 15 minutes late or worse, and those flights are late by roughly 55 minutes on average. That is a workable record, not a spotless one. That rests on 54,214 flights, of which Delta Air Lines flew 1,417 at 84.9% on time.

Delta Air Lines is the most reliable of the five carriers covered here at 84.9% on time across 1,417 flights.

On time

76.9%

Departures arriving under 15 minutes late at their destination

Avg delay

53 min

Across delayed flights only

Cancelled

0.84%

National rate is 1.81%

Best carrier

Delta

84.9% on time here

These figures cover 54,000 flights between July 2025 and June 2026. The median arrival is 3 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 HOU

The choice of carrier is not cosmetic here. Delta Air Lines arrives on time 84.9% of the time; SkyWest Airlines manages 70.6%. Sample sizes sit next to every figure, because a two-point gap across 380 flights means less than a ten-point one.

On-time performance by carrier departing HOU
Airline	Flights	On time	Avg delay	Cancelled	Grade
Southwest Airlines	50,515	76.7%	51 min	0.68%	B+
Delta Air Lines	1,417	84.9%	97 min	1.76%	B
Envoy Air	1,061	80.9%	68 min	2.73%	B
PSA Airlines	607	77.2%	103 min	5.77%	B−
SkyWest Airlines	380	70.6%	120 min	6.84%	C−

SkyWest Airlines cancels 6.8% of what it schedules here, the highest in the table. A cancelled flight never appears in an on-time rate, so read that column alongside the punctuality one rather than after it.

Route by route

Busiest routes out of HOU

Route-level records vary far more than the airport average. These are the 25 busiest departures from HOU, each with its own on-time rate against the airport-wide 76.9%.

Busiest routes from HOU by flight volume
Route	Flights	On time	Avg delay	Cancelled	Grade
HOU to DAL · Dallas	4,060	80.9%	58 min	2.19%	B
HOU to ATL · Atlanta	2,917	79.8%	66 min	1.13%	B
HOU to DEN · Denver	2,359	77.2%	52 min	0.42%	B+
HOU to MSY · New Orleans	2,277	83.4%	50 min	0.18%	B+
HOU to PHX · Phoenix	2,128	77.4%	52 min	0.42%	B+
HOU to DFW · Dallas-Fort Worth	2,048	77.9%	91 min	4.39%	B−
HOU to LAS · Las Vegas	2,045	80.7%	49 min	0.34%	B+
HOU to MCO · Orlando	2,035	77.0%	52 min	0.79%	B+
HOU to MDW · Chicago	1,834	72.7%	50 min	1.09%	C
HOU to BNA · Nashville	1,801	77.7%	48 min	0.61%	B+
HOU to STL · St. Louis	1,544	79.7%	53 min	0.26%	B+
HOU to BWI · Baltimore	1,457	75.4%	48 min	1.65%	B
HOU to AUS · Austin	1,403	74.1%	49 min	0.29%	C+
HOU to SAT · San Antonio	1,370	78.3%	50 min	0.07%	B+
HOU to LGA · New York	1,359	65.8%	63 min	2.43%	C
HOU to MAF · Midland	1,358	82.4%	51 min	0.52%	B+
HOU to OKC · Oklahoma City	1,251	76.8%	51 min	0.80%	B+
HOU to HRL · Harlingen	1,203	75.6%	46 min	0.08%	B+
HOU to LAX · Los Angeles	1,194	75.0%	46 min	0.08%	B+
HOU to DCA · Washington	1,056	70.9%	54 min	1.23%	C
HOU to ELP · El Paso	1,048	78.2%	48 min	0.38%	B+
HOU to TPA · Tampa	1,021	75.2%	49 min	0.29%	B+
HOU to MCI · Kansas City	1,002	75.9%	50 min	0.50%	B+
HOU to ABQ · Albuquerque	978	80.2%	52 min	0.41%	B+
HOU to CRP · Corpus Christi	976	77.4%	55 min	0.10%	B+

Departure window

The best time of day to leave HOU

Departure time matters more here than the choice of carrier. The gap between the best and worst window is 27 points, against 14 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.

5am–8am6,308 flights92.7%
8am–11am11,855 flights88.9%
11am–2pm8,713 flights79.3%
2pm–5pm9,313 flights68.6%
5pm–8pm8,728 flights67.6%
8pm–5am9,297 flights65.9%

Scale runs 55% to 100%. Rows with fewer than 30 flights show a dash.

Book the early departure. Flights leaving between 5am–8am arrive on time 92.7% of the time, against 65.9% for the overnight window. That is 27 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 11,855 flights scheduled in it.

Across the year

When HOU runs late

HOU's year swings by 24 points from best month to worst, which is wide. An annual average tells you very little about the week you are actually flying, so read the strip rather than the headline if your dates are fixed.

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

June is the worst month at 63.6% on time, 24 points below January, the best at 88.0%. 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. July was the busiest month here, with 5,093 flights.

Across the week, Tuesday is the strongest day at 81.4% on time and Sunday the weakest at 72.7%. 9 points is a smaller lever than departure hour, but it is free.

Delay causes

Why HOU gets delayed

One category carries most of the weight here. Late-arriving aircraft accounts for 46% of the 652,000 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
32%
National Airspace System
17%
Extreme weather
4%
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 652,000 reported delay minutes here, that single category outweighs weather by 11 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 652,098 reported delay minutes.

The practical consequence: the 5am–8am departure is the one that starts clean. Its aircraft has no earlier leg to be late from, which is exactly why that window shows 92.7% on time here.

Cancellations are rare at 0.84%, 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.

6.2% of arrivals land an hour or more late, close to the national 8.1%. 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 are the roughly 55 minutes kind, which a normal layover absorbs.

54,214 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 HOU

Put together: the calendar is the biggest lever here, not the carrier or the hour. January runs 88.0% on time and June 63.6%, a swing of 24 points. If the dates move at all, move them out of June before you think about anything else. 53,634 completed flights over 12 months sit behind that.

Common questions

HOU delay questions

How often is Houston (HOU) delayed?

Roughly one flight in four arrive at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 23.1% of the 54,214 flights in this analysis, against 22.4% nationally. Delayed flights are late by roughly 55 minutes on average.

Which airline is most reliable on Houston (HOU)?

Delta Air Lines leads at 84.9% on time across 1,417 flights. SkyWest Airlines is at the other end on 70.6%, a gap of 14 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 Houston (HOU)?

The 5am–8am departure window is the strongest at 92.7% on time. The 8pm–5am window is the weakest at 65.9%, 27 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 June delays on Houston (HOU)?

June is the weakest month at 63.6% on time, compared with 88.0% in January. Across the year that is 24 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, July 2025 to June 2026. Updated monthly. How this data is collected.

Key figures