Best Time to Fly SAT to BOS: On-Time Stats by Hour & Airline
San Antonio International → Logan International
Data through July 2026 · Last updated October 18, 2026
Over the last 12 months, 60.5% of San Antonio (SAT) to Boston (BOS) flights arrived on time (356 scheduled flights). That is 17.2 points below the national average of 77.6%.
Delta Air Lines was the only reporting airline with regular flights on this route.
Over 24 months, Saturday was the most reliable day (68% on time) and September the worst month (35%).
The cancellation rate was 2.2% (US average 1.8%).
SAT to BOS 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 | 60.5% | 81 min | 2.2% | 356 |
80%+ good 70–79.9% fair <70% poor
Best time of day to fly SAT to BOS
On-time arrival % by scheduled departure hour (local time), 669 flights over 24 months.
Show the numbers
| Departure hour | On time | Cancelled | Flights |
|---|---|---|---|
| 11am–12pm | 53.1% | 2.9% | 34 |
| 12pm–1pm | 73.3% | 1.1% | 175 |
| 1pm–2pm | 55.0% | 2.3% | 133 |
| 2pm–3pm | 59.2% | 0.8% | 237 |
| 3pm–4pm | 64.9% | 3.8% | 80 |
| 4pm–5pm | Limited data | 4 | |
| 5pm–6pm | Limited data | 6 | |
Best day of the week
24 months, by day of departure.
Best month to fly
24 months, by calendar month.
Holiday travel on SAT to BOS
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) | 51.7% | -12.6 pts | 3.2% | 123 |
| All other days | 64.3% | — | 1.2% | 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).