Carrier route record
UAPHX→IAH
United Airlines · Phoenix to Houston
- Flights
- 1,780
- Period
- July 2025 to June 2026
- Share of route
- 61%
- Carriers
- 5
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with United Airlines.
United on PHX 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 an hour and a half. That rests on 1,780 flights, with a median arrival 5 minutes early.
Set against the rest of the country, United's PHX to IAH record is 7 points better than the US average of 77.6%. That gap is worth roughly 70 fewer late arrivals for every thousand flights.
Key figures
On time
84.6%
Arrivals under 15 minutes late, of 1,760 completed flights
Avg delay
84 min
Across delayed arrivals only, not all flights
Cancelled
0.56%
National rate is 1.81%
Whole route
81.3%
Every carrier on PHX to IAH, 2,927 flights
These figures cover 1,780 flights between July 2025 and June 2026. The median arrival is 5 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 PHX to IAH
United flew 1,780 of the 2,927 flights on PHX to IAH, most of the route. Its 84.6% on time is 3 points better than the route as a whole, which runs 81.3%. Ranked by on-time rate it is first of five carriers on the route, where the range runs from United at 84.6% to SkyWest at 72.6%. Three of those carriers flew fewer than 365 flights here, so treat their positions as rough.
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 |
|---|---|---|---|---|---|
| United Airlines (this page) | 1,780 | 84.6% | 84 min | 0.56% | B+ |
| Envoy Airthin sample | 68 | 81.8% | 29 min | 0.00% | B+ |
| Frontier Airlinesthin sample | 277 | 78.5% | 62 min | 1.08% | B |
| American Airlines | 622 | 75.3% | 68 min | 1.45% | B |
| SkyWest Airlinesthin sample | 180 | 72.6% | 81 min | 2.78% | C |
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 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–8am365 flights93.1%
- 8am–11am474 flights85.0%
- 11am–2pm489 flights84.3%
- 2pm–5pm276 flights77.3%
- 5pm–8pm160 flights77.2%
- 8pm–5am16 flights—
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 93.1% of the time, against 77.2% 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 11am–2pm window is the busiest, with 489 flights scheduled in it.
Across the year
United on PHX to IAH through the year
July is the worst month at 76.5% on time, 20 points below February, the best at 96.1%. 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. March was the busiest month here, with 178 flights.
Across the week, Wednesday is the strongest day at 89.2% on time and Friday the weakest at 78.9%. 10 points is a smaller lever than departure hour, but it is free.
Delay causes
Why United runs late on this route
Carriers report a reason for every delay minute they cause, in five DOT categories. The split below is by minutes, not by number of flights, so a handful of very long weather delays weighs as much as many short ones. It covers 23,000 reported delay minutes.
- 39%Late-arriving aircraft
- 30%Carrier
- 28%National Airspace System
- 3%Extreme weather
39% 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 23,000 reported delay minutes here, that single category outweighs weather by 13 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 22,620 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 93.1% on time here.
Cancellations are rare at 0.56%, 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 costs
5.8% 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 an hour and a half, which a normal layover absorbs.
The 1,009 miles between these two airports put this in the middle of the US network, around two and a half to three hours of block time. That is enough cruise to absorb a ten-minute late pushback and not enough to absorb thirty. It is also long enough that the aircraft usually flies three or four legs a day rather than six, which slows how fast delay compounds.
The return leg is a different operation and performs like one: it runs 80.0% on time across 1,784 flights, 5 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 5 points of difference.
The sample behind these figures is 1,780 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 United on PHX to IAH
Put together: the calendar is the biggest lever here, not the carrier or the hour. February runs 96.1% on time and July 76.5%, a swing of 20 points. If the dates move at all, move them out of July before you think about anything else. 1,760 completed flights over 12 months sit behind that.
Related
Where to go next
- PHX to IAH, every carrier
- United on IAH to PHX, the return leg
- Frontier Airlines on PHX to IAH78.5%
- American Airlines on PHX to IAH75.3%
- SkyWest Airlines on PHX to IAH72.6%
- United Airlines network-wide record
- Phoenix Sky Harbor International (PHX) delay statistics
- George Bush Intercontinental (IAH) delay statistics
- Why the first flight of the morning is statistically safest
- The best time of day to fly, according to 7.04 million flight records
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.