Route reliability record
IAH→MSY
Houston to New Orleans
- Flights
- 2,962
- Period
- July 2025 to June 2026
- Distance
- 305 mi
- Carriers
- 4
This route lands a B+, 5 points better than the national rate of 77.6%. About one flight in six 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 2,962 flights, with a median arrival 9 minutes early.
Set against the rest of the country, this route's record is 5 points better than the US average of 77.6%. That gap is worth roughly 53 fewer late arrivals for every thousand flights.
Key figures
On time
82.9%
Arrivals under 15 minutes late, of 2,951 completed flights
Avg delay
65 min
Across delayed arrivals only, not all flights
Cancelled
0.30%
National rate is 1.81%
Best carrier
United
82.9% on time across 2,783 flights
These figures cover 2,962 flights between July 2025 and June 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.
Carrier by carrier
Which airline is most reliable on IAH to MSY
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.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Spirit Airlinesthin sample | 148 | 83.7% | 66 min | 0.68% | B+ |
| United Airlines | 2,783 | 82.9% | 63 min | 0.25% | B+ |
| Frontier Airlinesthin sample | 27 | 76.9% | 195 min | 3.70% | B− |
| SkyWest Airlinesthin sample | 4 | 75.0% | 138 min | 0.00% | B+ |
Departure window
The best time of day to leave
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 16 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–8am366 flights91.3%
- 8am–11am393 flights86.2%
- 11am–2pm368 flights86.1%
- 2pm–5pm598 flights82.2%
- 5pm–8pm512 flights75.5%
- 8pm–5am725 flights81.0%
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 75.5% for the evening window. That is 16 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 8pm–5am window is the busiest, with 725 flights scheduled in it.
Across the year
When delays peak on this route
This route'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.
July is the worst month at 67.6% on time, 24 points below September, the best at 91.8%. 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. October was the busiest month here, with 286 flights.
Across the week, Tuesday is the strongest day at 84.8% on time and Sunday the weakest at 80.4%. 4 points is a smaller lever than departure hour, but it is free.
Delay causes
Why this route gets delayed
One category carries most of the weight here. Late-arriving aircraft accounts for 45% of the 33,000 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.
- 45%Late-arriving aircraft
- 37%Carrier
- 13%National Airspace System
- 5%Extreme weather
45% 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 33,000 reported delay minutes here, that single category outweighs weather by 8 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 32,632 reported delay minutes.
The largest share of delay minutes, 37%, 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 12,000 of the 33,000 delay minutes reported here.
Cancellations are rare at 0.30%, 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.
Connections and stage length
What a delay here actually costs
6.5% 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 about an hour kind, which a normal layover absorbs.
At 305 miles this is a short hop, and stage length matters more than it looks. A flight this short spends under two hours in the air, which leaves almost nothing to claw back a late pushback with. Delay here is decided on the ground, in the turn, which is why the 5am–8am window matters as much as it does.
The return leg runs 82.2% on time across 2,961 flights, within half a point of this direction. The two legs are scored separately because they usually differ; on this city pair they happen not to.
The sample behind these figures is 2,962 flights, enough that the headline rate is stable to within roughly a point. The hour-block and month splits divide that further, so read the thinner bars with more caution than the headline.
What to do with this
Booking this route
Put together: the calendar is the biggest lever here, not the carrier or the hour. September runs 91.8% on time and July 67.6%, a swing of 24 points. If the dates move at all, move them out of July before you think about anything else. 2,951 completed flights over 12 months sit behind that.
Common questions
IAH to MSY questions
How often is IAH to MSY delayed?
About one flight in six arrive at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 17.1% of the 2,962 flights in this analysis, against 22.4% nationally. Delayed flights are late by about an hour on average.
How reliable is IAH to MSY compared with the rest of the country?
82.9% of flights arrive on time here against a national 77.6%, a difference of 5 points in its favour. That is worth a B+ on this site's grading scale.
What time of day has the fewest delays on IAH to MSY?
The 5am–8am departure window is the strongest at 91.3% on time. The 5pm–8pm window is the weakest at 75.5%, 16 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 IAH to MSY?
July is the weakest month at 67.6% on time, compared with 91.8% in September. 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.
Related
Where to go next
- MSY to IAH — the return legseparate record
- George Bush Intercontinental (IAH) delay statistics
- Louis Armstrong New Orleans International (MSY) delay statistics
- Spirit Airlines on-time record83.7%
- United Airlines on-time record82.9%
- Frontier Airlines on-time record76.9%
- Why the first flight of the morning is statistically safest
- The best time of day to fly, according to 7.04 million flight records
Direction matters. IAH to MSY and MSY to IAH are scored separately because they are separate operations, with different departure banks and different aircraft. Compare the return leg.
Source: US DOT Bureau of Transportation Statistics, on-time performance data, July 2025 to June 2026. Updated monthly. How this data is collected.