83% of flights from Houston to Salt Lake City arrived on time over the past 12 months. That is better than the typical U.S. route. The noon departures ran on time 86% of the time; the 8 p.m. ones 76%. Most reliable airline: United Airlines (84%). 6% of flights arrived more than an hour late or not at all.
How late?
The on-time rate treats a flight 20 minutes late the same as one 5 hours late. Here's the split for IAH → SLC: when a flight was late, it was under 45 minutes late 54% of the time. About 1 in 19 flights landed an hour or more late, and 1 in 91 three hours or more; 0.4% were cancelled outright.
- On time or early83%
- 15–30 min late5.7%
- 30–60 min late5.1%
- 1–2 hours late3.3%
- 2–3 hours late1.0%
- 3+ hours late1.1%
- Diverted0.3%
- Cancelled0.4%
Share of all 2,183 scheduled flights, past 12 months, by arrival time against schedule.
By airline
| Airline | Flights | On time | Cancelled | Typical arrival | 1h+ late | Avg when late | Operated by |
|---|---|---|---|---|---|---|---|
| United Airlines | 1,167 | 84% | 0.4% | −7 min | 4.7% | +60 min | United Airlines 73%, Mesa Airlines 22%, SkyWest 5% |
| Delta Air Lines | 1,016 | 83% | 0.4% | −9 min | 6.0% | +90 min | Delta Air Lines |
Airline = the name on the ticket. Regional flights (e.g. "Delta Connection") count under the ticketing airline, and the operator is listed.
Best time of day to fly
On-time rate by scheduled departure hour (local time at IAH). Delays build through the day as late planes knock on, so early flights usually do best.
By airline and hour
| Departs | United Airlines | Delta Air Lines |
|---|---|---|
| 7 a.m. | — | 85% |
| 9 a.m. | 86% | — |
| 11 a.m. | — | 85% |
| noon | 88% | — |
| 7 p.m. | — | 76% |
| 8 p.m. | 76% | — |
Last flight of the day
On IAH → SLC, each airline's last flight of the day was cancelled 0.5% of the time, against 0.3% for its earlier flights (1.6× as often). It arrived 3+ hours late 1.9% of the time (earlier flights: 0.7%). It matters more than the numbers suggest. Miss an earlier flight and there's another one that evening; miss the last one and you're usually waiting until morning.
| Airline | Last departure | Last: cancelled | Last: 3h+ late | Earlier: cancelled | Next morning |
|---|---|---|---|---|---|
| Delta Air Lines | 7:01 p.m. | 0.3% | 1.9% | 0.5% | first flight 7:35 a.m. |
| United Airlines | 8:25 p.m. | 0.8% | 1.9% | 0.3% | first flight 9:45 a.m. |
Last flight = the airline's last scheduled departure on this route that day, on days it flies the route at least twice; past 12 months. Times are typical scheduled times over the latest three months.
If you need to be in SLC tonight, book an earlier flight so there's a backup if it's cancelled.
By month
Each calendar month pooled over 2023–2026. Best: November (87%). Worst: July (72%).
By day of week
| Day | Flights | On time | Cancelled |
|---|---|---|---|
| Monday | 326 | 81% | 1.5% |
| Tuesday | 314 | 86% | 0.6% |
| Wednesday | 315 | 81% | 0.0% |
| Thursday | 318 | 84% | 0.0% |
| Friday | 326 | 83% | 0.0% |
| Saturday | 271 | 87% | 0.4% |
| Sunday | 313 | 81% | 0.3% |
Why flights were late
Share of delay minutes on flights 15+ minutes late, as reported to BTS by the airlines.
Cancellations: weather 5 · airline 3 · air traffic/airport 1
Month by month
Flight numbers on this route
Regular flights with at least 120 scheduled trips in the past year. Sorted by departure time.
| Flight | Departs | Flights | On time | Cancelled | Typical arrival | Operated by |
|---|---|---|---|---|---|---|
| DL 1583 | 7:40 a.m. | 365 | 85% | 0.5% | −9 min | Delta Air Lines |
| UA 2242 | 9:45 a.m. | 295 | 85% | 0.3% | −6 min | United Airlines |
| DL 1532 | 11:34 a.m. | 324 | 83% | 0.6% | −10 min | Delta Air Lines |
| DL 1299 | 7:01 p.m. | 195 | 78% | 0.0% | −11 min | Delta Air Lines |
| UA 2157 | 8:25 p.m. | 362 | 76% | 0.8% | −2 min | United Airlines |
Worst days in the past year
| Date | Flights | On time | Cancelled |
|---|---|---|---|
| Mar 11, 2026 | 7 | 0% | 0 |
| Jun 19, 2026 | 6 | 0% | 0 |
| Oct 25, 2025 | 5 | 0% | 0 |
| May 23, 2026 | 4 | 0% | 0 |
| Mar 16, 2026 | 7 | 14% | 3 |
Nearby airport alternatives
Other ways to make the same trip, using airports within 60 miles of Houston or Salt Lake City. None has been clearly more reliable than IAH → SLC.
| Route | Flights | On time | Cancelled |
|---|---|---|---|
| IAH → SLC (this route) | 2,183 | 83% | 0.4% |
| HOU → SLC Houston Hobby to Salt Lake City | 410 | 78% | 0.5% |
Questions
How often are flights from IAH to SLC on time?
83% of 2,183 scheduled flights from Houston, TX to Salt Lake City, UT arrived within 15 minutes of schedule between September 2025 and August 2026. 0.4% were cancelled.
What is the best time of day to fly IAH to SLC?
Flights scheduled to leave at noon were the most reliable (86% on time). The 8 p.m. departures were the least (76%).
Which airline is most on time from IAH to SLC?
United Airlines: 84% of its 1,167 flights on the route arrived on time. Delta Air Lines: 83%.
What month has the most delays from IAH to SLC?
July (72% on time). The best month is November (87%), over 2023–2026.
Is the last flight of the day from IAH to SLC more likely to be cancelled?
Yes. Each airline's last IAH–SLC flight of the day was cancelled 0.5% of the time over the past year, against 0.3% for its earlier flights. If the last flight is cancelled, the next one is usually the following morning.
Related
- SLC → IAH (return)
- Houston Bush Intercontinental (IAH) delays by hour
- Flights into Salt Lake City (SLC)
- United Airlines on-time record
- Delta Air Lines on-time record
- Connecting off this flight? Check the risk
Domestic flights by the airlines that report to the U.S. DOT, plus their regional partners. "On time" means arriving less than 15 minutes after schedule; cancelled and diverted flights count as not on time. Past performance is a guide, not a forecast. Method.