84% of flights from Los Angeles to Houston arrived on time over the past 12 months. That is better than the typical U.S. route. The 6 a.m. departures ran on time 96% of the time; the 1 p.m. ones 71%. Most reliable airline: United Airlines (87%). 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 LAX → IAH: when a flight was late, it was under 45 minutes late 59% of the time. About 1 in 21 flights landed an hour or more late, and 1 in 120 three hours or more; 0.5% were cancelled outright.
- On time or early84%
- 15–30 min late6.3%
- 30–60 min late4.2%
- 1–2 hours late3.0%
- 2–3 hours late1.0%
- 3+ hours late0.8%
- Diverted0.2%
- Cancelled0.5%
Share of all 5,143 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 | 3,420 | 87% | 0.2% | −9 min | 3.0% | +52 min | United Airlines |
| Delta Air Lines | 648 | 84% | 0.9% | −7 min | 5.2% | +70 min | Delta Air Lines |
| American Airlines | 408 | 81% | 0.5% | −6 min | 7.6% | +70 min | SkyWest |
| Frontier Airlines | 336 | 69% | 1.5% | 0 min | 13.4% | +74 min | Frontier Airlines |
| Spirit Airlines | 331 | 72% | 1.5% | +2 min | 10.0% | +73 min | Spirit Airlines |
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 LAX). 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 | American Airlines |
|---|---|---|---|
| 12 a.m. | 89% | — | — |
| 5 a.m. | 95% | — | — |
| 6 a.m. | 96% | — | — |
| 7 a.m. | 94% | — | — |
| 8 a.m. | 92% | 89% | — |
| 9 a.m. | 89% | 81% | — |
| 10 a.m. | 89% | — | — |
| 11 a.m. | 85% | — | — |
| noon | 88% | — | — |
| 1 p.m. | 70% | — | 78% |
| 2 p.m. | — | — | 77% |
| 3 p.m. | 83% | — | — |
| 4 p.m. | 88% | — | — |
| 6 p.m. | 82% | 83% | — |
| 7 p.m. | 89% | — | — |
| 11 p.m. | 88% | — | — |
Last flight of the day
On LAX → IAH, each airline's last flight of the day was cancelled 0.6% of the time, against 0.2% for its earlier flights (3.2× as often). It arrived 3+ hours late 1.1% 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 | 6:35 p.m. | 1.4% | 0.7% | 0.7% | first flight 9:40 a.m. |
| United Airlines | 7:21 p.m. | 0.3% | 0.8% | 0.2% | first flight 12:51 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 IAH tonight, book an earlier flight so there's a backup if it's cancelled.
By month
Each calendar month pooled over 2023–2026. Best: September (91%). Worst: July (76%).
By day of week
| Day | Flights | On time | Cancelled |
|---|---|---|---|
| Monday | 781 | 84% | 0.6% |
| Tuesday | 687 | 85% | 0.6% |
| Wednesday | 719 | 87% | 0.1% |
| Thursday | 763 | 87% | 0.0% |
| Friday | 767 | 82% | 0.4% |
| Saturday | 660 | 82% | 0.6% |
| Sunday | 766 | 81% | 0.9% |
Why flights were late
Share of delay minutes on flights 15+ minutes late, as reported to BTS by the airlines.
Cancellations: airline 13 · weather 11
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 |
|---|---|---|---|---|---|---|
| UA 491 | 12:55 a.m. | 286 | 90% | 0.4% | −9 min | United Airlines |
| UA 654 | 5:45 a.m. | 253 | 95% | 0.0% | −11 min | United Airlines |
| UA 1397 | 7:05 a.m. | 150 | 95% | 0.0% | −11 min | United Airlines |
| UA 1416 | 8:15 a.m. | 320 | 92% | 0.0% | −12 min | United Airlines |
| DL 1143 | 9:40 a.m. | 365 | 85% | 0.5% | −6 min | Delta Air Lines |
| UA 277 | 10:10 a.m. | 180 | 87% | 0.0% | −8 min | United Airlines |
| UA 2086 | 11:54 a.m. | 261 | 85% | 0.0% | −3 min | United Airlines |
| UA 1591 | 1:10 p.m. | 180 | 72% | 0.0% | +3 min | United Airlines |
| UA 2377 | 3:20 p.m. | 364 | 85% | 0.5% | −7 min | United Airlines |
| UA 2403 | 5:45 p.m. | 162 | 82% | 0.0% | −11 min | United Airlines |
| F9 1756 | 6:25 p.m. | 310 | 69% | 1.3% | 0 min | Frontier Airlines |
| DL 1287 | 6:40 p.m. | 283 | 83% | 1.4% | −7 min | Delta Air Lines |
| UA 1680 | 6:45 p.m. | 167 | 87% | 0.0% | −14 min | United Airlines |
Worst days in the past year
| Date | Flights | On time | Cancelled |
|---|---|---|---|
| Mar 16, 2026 | 15 | 20% | 2 |
| Mar 11, 2026 | 14 | 21% | 0 |
| Jun 15, 2026 | 14 | 36% | 0 |
| May 1, 2026 | 15 | 40% | 0 |
| Aug 27, 2026 | 12 | 42% | 0 |
Nearby airport alternatives
Other ways to make the same trip, using airports within 60 miles of Los Angeles or Houston. SNA → IAH has been 4 points more reliable.
| Route | Flights | On time | Cancelled |
|---|---|---|---|
| LAX → IAH (this route) | 5,143 | 84% | 0.5% |
| SNA → IAH Orange County John Wayne to Houston Bush Intercontinental | 1,092 | 88% | 0.0% |
| ONT → IAH Ontario to Houston Bush Intercontinental | 574 | 85% | 1.2% |
| LGB → HOU Long Beach to Houston Hobby | 440 | 77% | 0.2% |
| LAX → HOU Los Angeles LAX to Houston Hobby | 1,194 | 69% | 0.2% |
Questions
How often are flights from LAX to IAH on time?
84% of 5,143 scheduled flights from Los Angeles, CA to Houston, TX arrived within 15 minutes of schedule between September 2025 and August 2026. 0.5% were cancelled.
What is the best time of day to fly LAX to IAH?
Flights scheduled to leave at 6 a.m. were the most reliable (96% on time). The 1 p.m. departures were the least (71%).
Which airline is most on time from LAX to IAH?
United Airlines: 87% of its 3,420 flights on the route arrived on time. Delta Air Lines: 84%. American Airlines: 81%. Frontier Airlines: 69%. Spirit Airlines: 72%.
What month has the most delays from LAX to IAH?
July (76% on time). The best month is September (91%), over 2023–2026.
Is the last flight of the day from LAX to IAH more likely to be cancelled?
Yes. Each airline's last LAX–IAH flight of the day was cancelled 0.6% of the time over the past year, against 0.2% for its earlier flights. If the last flight is cancelled, the next one is usually the following morning.
Related
- IAH → LAX (return)
- Los Angeles LAX (LAX) delays by hour
- Flights into Houston Bush Intercontinental (IAH)
- United Airlines on-time record
- Delta Air Lines on-time record
- American Airlines on-time record
- Frontier Airlines on-time record
- Spirit Airlines 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.