Best Time to Fly GSP to HOU: On-Time Stats by Hour & Airline
Greenville-Spartanburg International → William P Hobby
Data through July 2026 · Last updated October 18, 2026
Over the last 12 months, 89.4% of Greer (GSP) to Houston (HOU) flights arrived on time (173 scheduled flights). That is 11.8 points above the national average of 77.6%.
Southwest Airlines was the only reporting airline with regular flights on this route.
Over 24 months, Saturday was the most reliable day (89% on time) and July the worst month (52%).
The cancellation rate was 1.7% (US average 1.8%).
GSP to HOU on-time performance by airline
Last 12 months. Airlines with fewer than 30 completed flights are marked “limited data”.
| Airline | On time | Avg delay when late | Cancelled | Flights |
|---|---|---|---|---|
| Southwest Airlines | 89.4% | 51 min | 1.7% | 173 |
80%+ good 70–79.9% fair <70% poor
Best time of day to fly GSP to HOU
On-time arrival % by scheduled departure hour (local time), 329 flights over 24 months.
Show the numbers
| Departure hour | On time | Cancelled | Flights |
|---|---|---|---|
| 12pm–1pm | Limited data | 20 | |
| 1pm–2pm | 96.8% | 0.0% | 31 |
| 2pm–3pm | Limited data | 20 | |
| 3pm–4pm | 92.6% | 0.0% | 54 |
| 4pm–5pm | 86.8% | 3.6% | 55 |
| 5pm–6pm | Limited data | 10 | |
| 6pm–7pm | 86.0% | 0.0% | 43 |
| 7pm–8pm | 72.7% | 0.0% | 44 |
| 8pm–9pm | 55.8% | 0.0% | 52 |
Best day of the week
24 months, by day of departure.
Best month to fly
24 months, by calendar month.
Holiday travel on GSP to HOU
On-time arrivals during holiday periods compared with all other days, last 24 months.
| Period | On time | vs other days | Cancelled | Flights |
|---|---|---|---|---|
| Thanksgiving week (Tue before to Mon after) | Limited data | 8 | ||
| Christmas & New Year (Dec 20 - Jan 3) | Limited data | 17 | ||
| Summer peak (Jun 15 - Aug 15) | 61.5% | -25.3 pts | 0.0% | 65 |
| All other days | 86.9% | — | 1.3% | 239 |
Monthly on-time trend
On-time arrival % each month, with the 12-month US average for reference.
What causes delays on this route
Share of reported delay minutes, last 12 months (BTS cause categories).