Carrier route record
UASLC→IAH
United Airlines · Salt Lake City to Houston
- Flights
- 854
- Period
- September 2025 to August 2026
- Share of route
- 44%
- Carriers
- 3
Historical statistics for September 2025 to August 2026, not live status. For today’s flights, check with United Airlines.
United on SLC to IAH earns an A. Close to nine flights in ten arrive inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 12 points better than the national rate of 77.3%. When something does go wrong the average delay runs a little over an hour. That rests on 854 flights, with a median arrival 10 minutes early.
Set against the rest of the country, United's SLC to IAH record is 12 points better than the US average of 77.3%. That gap is worth roughly 122 fewer late arrivals for every thousand flights.
Key figures
On time
89.5%
Arrivals under 15 minutes late, of 840 completed flights
Avg delay
79 min
Across delayed arrivals only, not all flights
Cancelled
1.29%
National rate is 1.89%
Whole route
86.1%
Every carrier on SLC to IAH, 1,931 flights
These figures cover 854 flights between September 2025 and August 2026. The median arrival is 10 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.
Fare search by Aviasales, a Travelpayouts partner. Booking through it may earn this site a commission at no cost to you; it changes no figure here.
Carrier by carrier
United against every carrier on SLC to IAH
United flew 854 of the 1,931 flights on SLC to IAH, about 44% of it. Its 89.5% on time is 3 points better than the route as a whole, which runs 86.1%. Ranked by on-time rate it is first of three carriers on the route, where the range runs from United at 89.5% to Delta at 83.1%. One 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) | 854 | 89.5% | 79 min | 1.29% | A |
| SkyWest Airlinesthin sample | 61 | 88.1% | 58 min | 1.64% | A |
| Delta Air Lines | 1,016 | 83.1% | 77 min | 0.20% | B+ |
Flight by flight
United flight numbers on SLC to IAH
Timetable by Aviasales, a Travelpayouts partner. Booking through it may earn this site a commission at no cost to you; it changes no figure here.
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 11 points, against half a point between the best and worst carrier.
- 5am–8am363 flights94.4%
- 8am–11am18 flights—
- 11am–2pm357 flights83.7%
- 2pm–5pm116 flights90.4%
- 5pm–8pm—
- 8pm–5am—
Scale runs 75% to 100%. Rows with fewer than 30 flights show a dash.
The weak window here is the middle of the day, not the evening: 11am–2pm runs 83.7% on time against 94.4% for 5am–8am. That shape usually means a departure bank rather than an accumulating delay, so the recovery later in the afternoon is real rather than noise. The 5am–8am window is the busiest, with 363 flights scheduled in it.
Across the year
United on SLC to IAH through the year
Delays peak in May, when the on-time rate falls to 77.0%. December is the strongest month at 94.7%. Moving a flexible trip across that boundary buys 18 points. January was the busiest month here, with 98 flights.
Across the week, Friday is the strongest day at 93.2% on time and Wednesday the weakest at 86.1%, a spread of 7 points.
Arrival by arrival
How late United on SLC to IAH runs when it is late
United on SLC to IAH often beats the schedule: 313 of 840 completed flights, 37%, arrived 15 minutes or more early. The 88 late arrivals split 27 under half an hour, 31 between 30 and 60 minutes, and 30 an hour or more.
- 15+ min early313 flights37.3%
- Within 15 min439 flights52.3%
- 15–29 min late27 flights3.2%
- 30–59 min late31 flights3.7%
- 1–2 hours late11 flights1.3%
- 2+ hours late19 flights2.3%
Scale runs 0% to 100%.
Share of 840 completed flights by arrival against schedule.
A late pushback is often recovered here: of 105 departures that left 15 minutes late or more, 37 still arrived on time. 20 flights left on time and still arrived late.
The worst days
Worst days for United on SLC to IAH
The latest arrival of the period was on 25 April 2026, 6 hours 14 minutes behind schedule; most of its delay minutes were filed as carrier-caused (crew, maintenance, fuelling, baggage). The same cause led on three of the five worst days.
| Date | Arrived late by | Largest filed cause |
|---|---|---|
| 25 April 2026 | 6 hours 14 minutes | Carrier |
| 9 March 2026 | 5 hours 50 minutes | Late-arriving aircraft |
| 1 January 2026 | 5 hours 14 minutes | Carrier |
| 18 February 2026 | 5 hours 9 minutes | Late-arriving aircraft |
| 11 February 2026 | 5 hours 7 minutes | Carrier |
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 6,905 reported delay minutes.
- 42%Carrier
- 29%Late-arriving aircraft
- 29%National Airspace System
- 0%Extreme weather
The largest share of delay minutes, 42%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. It accounts for 2,894 of the 6,905 delay minutes reported here. The split is drawn from 6,905 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 94.4% on time here.
Cancellations sit at 1.29% against a national 1.89%, which is ordinary. Diversions add another 0.35%.
Connections and stage length
What a delay here costs
Badly late arrivals are rare here: only 3.6% land an hour or more behind schedule, against 8.3% 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.
The 1,195 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.
The return leg is a different operation and performs like one: it runs 83.6% on time across 856 flights, 6 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 6 points of difference.
One caution: this is a thin sample. 854 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 SLC to IAH
Put together: treat all of this as provisional. 854 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 89.5% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 840 completed flights over 12 months sit behind that.
Related
Where to go next
- SLC to IAH, every carrier
- United on IAH to SLC, the return leg
- Delta Air Lines on SLC to IAH83.1%
- United Airlines network-wide record
- Salt Lake City International (SLC) delay statistics
- George Bush Intercontinental (IAH) delay statistics
- The best time of day to fly, according to 7.05 million flight records
- Worst months to fly in the US, ranked by the data
Source: US DOT Bureau of Transportation Statistics, on-time performance data, September 2025 to August 2026. Last updated ; recomputed monthly. How this data is collected.