Carrier route record

UAOKC→IAH

United Airlines · Oklahoma City to Houston

Flights: 308
Period: July 2025 to June 2026
Share of route: 22%
Carriers: 2

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

United on OKC to IAH lands a B+, 2 points better than the national rate of 77.6%. About one flight in five arrives 15 minutes late or worse, and those flights are late by a little over an hour on average. That is a workable record, not a spotless one. That rests on 308 flights, with a median arrival 7 minutes early.

The US average over the same twelve months is 77.6%, so there is little to separate United on OKC to IAH from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.

On time

80.0%

Arrivals under 15 minutes late, of 305 completed flights

Avg delay

80 min

Across delayed arrivals only, not all flights

Cancelled

0.97%

National rate is 1.81%

Whole route

84.3%

Every carrier on OKC to IAH, 1,399 flights

These figures cover 308 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 OKC to IAH

United flew 308 of the 1,399 flights on OKC to IAH, about 22% of it. Its 80.0% on time is 4 points worse than the route as a whole, which runs 84.3%. Ranked by on-time rate it is last of two carriers on the route, where the range runs from SkyWest at 85.6% to United at 80.0%.

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 OKC to IAH
Airline	Flights	On time	Avg delay	Cancelled	Grade
SkyWest Airlines	1,091	85.6%	77 min	1.01%	A
United Airlines (this page)thin sample	308	80.0%	80 min	0.97%	B+

Departure window

When United runs best on this route

Departure time matters more here than the choice of carrier. The gap between the best and worst window is 29 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–8am41 flights61.0%
8am–11am183 flights90.0%
11am–2pm2 flights—
2pm–5pm35 flights71.4%
5pm–8pm47 flights63.8%
8pm–5am—

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

Book the morning departure. Flights leaving between 8am–11am arrive on time 90.0% of the time, against 61.0% for the early window. That is 29 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 183 flights scheduled in it.

Across the year

United on OKC to IAH through the year

Jul–Sep 202556 flights78.6%
Oct–Dec 202574 flights74.3%
Jan–Mar 202688 flights90.6%
Apr–Jun 202690 flights75.6%

Scale runs 65% 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 80.0% on time across 308 flights.

United on OKC to IAH did not run the same all year. Its best quarter was Jan–Mar 2026 at 90.6% on time and its weakest Oct–Dec 2025 at 74.3%, a swing of 16 points on roughly 77 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, Wednesday is the strongest day at 91.1% on time and Sunday the weakest at 66.7%. 24 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 57% of the 4,859 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
57%
Carrier
21%
Late-arriving aircraft
21%
Extreme weather
1%

57% 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 2,772 minutes out of 4,859, against a national NAS share of 21%. The split is drawn from 4,859 reported delay minutes.

Cancellations sit at 0.97% against a national 1.81%, which is ordinary. Diversions add another 0.00%.

Connections and stage length

What a delay here costs

7.2% 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 last a little over an hour, which a normal layover absorbs.

At 395 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 8am–11am window matters as much as it does.

The return leg runs 82.2% on time across 307 flights, within 2 points of this direction. The two legs are scored separately because they usually differ; on this city pair they happen not to.

One caution: this is a thin sample. 308 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 OKC to IAH

Put together: treat all of this as provisional. 308 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 80.0% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 305 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