Best Time to Fly BOS to SAT: On-Time Stats by Hour & Airline
Logan International → San Antonio International
Data through July 2026 · Last updated October 18, 2026
Over the last 12 months, 77.0% of Boston (BOS) to San Antonio (SAT) flights arrived on time (356 scheduled flights). That is 0.6 points below the national average of 77.6%.
Delta Air Lines was the only reporting airline with regular flights on this route.
March has been the best month (93% on time) and Sunday the weakest day of the week (76%).
2.2% of flights were cancelled, versus 1.8% nationally.
BOS 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 |
|---|---|---|---|---|
| Delta Air Lines | 77.0% | 85 min | 2.2% | 356 |
80%+ good 70–79.9% fair <70% poor
Best time of day to fly BOS to SAT
On-time arrival % by scheduled departure hour (local time), 669 flights over 24 months.
Show the numbers
| Departure hour | On time | Cancelled | Flights |
|---|---|---|---|
| 7am–8am | 86.7% | 6.2% | 48 |
| 8am–9am | Limited data | 25 | |
| 9am–10am | 75.2% | 1.5% | 333 |
| 10am–11am | 84.5% | 1.4% | 72 |
| 11am–12pm | 83.7% | 2.8% | 107 |
| 12pm–1pm | 80.3% | 0.0% | 76 |
| 1pm–2pm | Limited data | 8 | |
Best day of the week
24 months, by day of departure.
Best month to fly
24 months, by calendar month.
Holiday travel on BOS 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 | 10 | ||
| Christmas & New Year (Dec 20 - Jan 3) | Limited data | 21 | ||
| Summer peak (Jun 15 - Aug 15) | 71.5% | -10.0 pts | 4.9% | 123 |
| All other days | 81.6% | — | 1.0% | 515 |
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).