Best Time to Fly SEA to SAT: On-Time Stats by Hour & Airline
Seattle/Tacoma International → San Antonio International
Data through July 2026 · Last updated October 18, 2026
Over the last 12 months, 75.7% of Seattle (SEA) to San Antonio (SAT) flights arrived on time (558 scheduled flights). That is 1.9 points below the national average of 77.6%.
Alaska Airlines was the only reporting airline with regular flights on this route.
Over 24 months, Tuesday was the most reliable day (79% on time) and July the worst month (57%).
The cancellation rate was 0.9% (US average 1.8%).
SEA to SAT 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 |
|---|---|---|---|---|
| Alaska Airlines | 75.7% | 41 min | 0.9% | 558 |
80%+ good 70–79.9% fair <70% poor
Best time of day to fly SEA to SAT
On-time arrival % by scheduled departure hour (local time), 1,150 flights over 24 months.
Show the numbers
| Departure hour | On time | Cancelled | Flights |
|---|---|---|---|
| 7am–8am | 91.2% | 0.0% | 34 |
| 8am–9am | Limited data | 27 | |
| 9am–10am | 65.4% | 0.0% | 52 |
| 10am–11am | 83.3% | 0.0% | 84 |
| 11am–12pm | 70.8% | 0.9% | 225 |
| 12pm–1pm | 72.2% | 0.7% | 294 |
| 5pm–6pm | 85.1% | 1.3% | 75 |
| 6pm–7pm | Limited data | 14 | |
| 10pm–11pm | 53.9% | 0.0% | 52 |
| 11pm–12am | 76.5% | 0.7% | 293 |
Best day of the week
24 months, by day of departure.
Best month to fly
24 months, by calendar month.
Holiday travel on SEA to SAT
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 | 26 | ||
| Christmas & New Year (Dec 20 - Jan 3) | 70.2% | -8.4 pts | 0.0% | 57 |
| Summer peak (Jun 15 - Aug 15) | 62.3% | -16.3 pts | 0.8% | 246 |
| All other days | 78.6% | — | 0.6% | 821 |
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).