Carrier route record

UAMEM→IAH

United Airlines · Memphis to Houston

Flights: 360
Period: July 2025 to June 2026
Share of route: 33%
Carriers: 2

Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with United Airlines.

United on MEM to IAH earns a B. More than four flights in five arrive inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 7 points better than the national rate of 77.6%. When something does go wrong the average delay runs roughly 50 minutes. That rests on 360 flights, with a median arrival 7 minutes early.

Set against the rest of the country, United's MEM to IAH record is 7 points better than the US average of 77.6%. That gap is worth roughly 69 fewer late arrivals for every thousand flights.

On time

84.5%

Arrivals under 15 minutes late, of 354 completed flights

Avg delay

48 min

Across delayed arrivals only, not all flights

Cancelled

1.67%

National rate is 1.81%

Whole route

80.1%

Every carrier on MEM to IAH, 1,082 flights

These figures cover 360 flights between July 2025 and June 2026. The median arrival is 7 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

United against every carrier on MEM to IAH

United flew 360 of the 1,082 flights on MEM to IAH, about 33% of it. Its 84.5% on time is 4 points better than the route as a whole, which runs 80.1%. Ranked by on-time rate it is first of two carriers on the route, where the range runs from United at 84.5% to SkyWest at 77.9%.

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.

On-time performance by carrier on MEM to IAH
Airline	Flights	On time	Avg delay	Cancelled	Grade
United Airlines (this page)thin sample	360	84.5%	48 min	1.67%	B
SkyWest Airlines	722	77.9%	79 min	0.69%	B+

Departure window

When United runs best on this route

Departure time is the single lever a traveller controls, and it moves the odds more than most people expect. Each bar below is the on-time rate for flights scheduled to leave inside that window, across 360 flights.

There are not enough flights in each departure window to split United's MEM to IAH record by time of day without the percentages moving on noise. The headline rate of 84.5% is the reliable figure here.

Across the year

United on MEM to IAH through the year

Jul–Sep 202585 flights90.5%
Oct–Dec 202591 flights80.2%
Jan–Mar 202690 flights80.2%
Apr–Jun 202694 flights87.1%

Scale runs 70% to 95%. Rows with fewer than 30 flights show a dash.

Monthly volumes are too low here to break the year into twelve reliable readings. What the twelve-month total says is 84.5% on time across 360 flights.

United on MEM to IAH did not run the same all year. Its best quarter was Jul–Sep 2025 at 90.5% on time and its weakest Jan–Mar 2026 at 80.2%, a swing of 10 points on roughly 90 flights a quarter. The twelve-month rate averages over that, so if you are flying in a weak quarter the quarter's own figure is the better guide.

Across the week, Thursday is the strongest day at 90.2% on time and Wednesday the weakest at 79.5%. 11 points is a smaller lever than departure hour, but it is free.

Delay causes

Why United runs late on this route

One category carries most of the weight here. National Airspace System accounts for 61% of the 2,612 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.

National Airspace System
61%
Carrier
38%
Extreme weather
2%

61% of delay minutes are charged to the National Airspace System: air traffic volume, runway configuration, ground stops. No carrier can price its way out of that, which is why airport choice moves the number here more than carrier choice does. That is 1,585 minutes out of 2,612, against a national NAS share of 21%. The split is drawn from 2,612 reported delay minutes.

The largest share of delay minutes, 38%, 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 980 of the 2,612 delay minutes reported here.

Cancellations sit at 1.67% against a national 1.81%, which is ordinary. Diversions add another 0.00%.

Connections and stage length

What a delay here costs

Badly late arrivals are rare here: only 3.1% land an hour or more behind schedule, against 8.1% 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.

At 468 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 is a different operation and performs like one: it runs 71.5% on time across 359 flights, 13 points below this direction. Departure banks, aircraft rotations and the congestion at each end all differ, so scoring the two directions together would average away a real 13 points of difference.

One caution: this is a thin sample. 360 flights over twelve months is enough to clear this site's floor but not enough to pin the rate down tightly, and a single bad week moves it by more than a point. Treat the grade as a rough reading.

What to do with this

Booking United on MEM to IAH

Put together: treat all of this as provisional. 360 flights over twelve months is enough to clear this site's floor and not enough to be confident to better than a couple of points. The 84.5% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 354 completed flights over 12 months sit behind that.

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