Houston (IAH) to Las Vegas (LAS): On-Time Performance
Data through May 2026
When you fly IAH to LAS matters as much as anything else about the booking: the route swung from 91% on-time in February 2026 to just 57% in July 2024. Across the full period the route averages 80% on-time against a national 78%. Morning departures also hold up better than evening ones (88% vs 74%), which matters most in the rough months.
- On-time
- 80%
- arrived <15 min late
- Avg delay
- 15 min
- completed flights
- Cancelled
- 1.1%
- Flights/day
- 9.5
- last 12 months
- Duration
- 3h 23m
- scheduled
- Distance
- 1,222 mi
Best airline from IAH to LAS
4 airlines flew this route regularly between 2024-06 and 2026-05.
| Airline | On-time | Avg delay | Cancelled | Flights |
|---|---|---|---|---|
| United Airlinesmost reliable | 82% | 12 min | 0.7% | 5,157 |
| Spirit Airlines | 80% | 16 min | 1.5% | 1,625 |
| Southwest Airlines | 73% | 17 min | 3.2% | 155 |
| Frontier Airlines | 71% | 36 min | 2.3% | 577 |
Monthly on-time trend
Best time to fly from IAH to LAS
Aim for departures around 7 a.m. (92% on-time); avoid 7 p.m. departures (66%).
By day of week
| Day | On-time | Avg delay |
|---|---|---|
| Monday | 78% | 19 min |
| Tuesday | 84% | 10 min |
| Wednesdaybest | 84% | 12 min |
| Thursday | 78% | 16 min |
| Friday | 76% | 18 min |
| Saturday | 83% | 13 min |
| Sunday | 80% | 16 min |
What causes delays on this route
Share of total delay minutes by cause, as reported by carriers to the US DOT.
- Late-arriving aircraft37%
- Airline operations36%
- National airspace system22%
- Weather6%
Frequently asked questions
- How often are flights from IAH to LAS delayed?
- 20% of IAH–LAS flights arrived 15 or more minutes late (the US DOT definition of a delay) between 2024-06 and 2026-05. The average arrival delay across completed flights was 15 minutes.
- Which airline is most reliable from IAH to LAS?
- United Airlines has the best on-time record on this route at 82%, based on 5,157 flights. 4 airlines flew IAH–LAS frequently enough to compare in this period.
- What is the best time of day to fly from IAH to LAS?
- Departures around 7 a.m. have the best record (92% on-time), while departures around 7 p.m. have the worst (66%). As on most US routes, delays accumulate through the day, so earlier flights are generally safer.
- How long is the flight from IAH to LAS?
- The scheduled IAH–LAS flight time averages 3h 23m over 1,222 miles. Actual arrival times vary — flights on this route land 15+ minutes late 20% of the time.
- How often are IAH to LAS flights cancelled?
- 1.1% of scheduled flights on this route were cancelled between 2024-06 and 2026-05, at or below the national rate of 1.6%.
- What is the worst month to fly from IAH to LAS?
- July 2024 was the roughest month in this dataset, with only 57% of arrivals on time. The best was February 2026 at 91%. If your dates are flexible, that 34-point gap is worth planning around.
Explore related pages
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Based on 7,514 flights, 2024-06–2026-05. Source: US DOT Bureau of Transportation Statistics. Updated 2026-07-01.