Best Time to Fly SAN to BOS: On-Time Stats by Hour & Airline
San Diego International → Logan International
Data through July 2026 · Last updated October 18, 2026
1,849 flights were scheduled from San Diego (SAN) to Boston (BOS) in the last 12 months, and 77.1% of those that flew arrived on time, 0.5 points below the US average of 77.6%.
Delta Air Lines was the most punctual of the 4 airlines on the route at 79.6%, while Southwest Airlines trailed at 32.8%.
January has been the best month (85% on time) and Thursday the weakest day of the week (71%).
1.6% of flights were cancelled, versus 1.8% nationally.
SAN 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 | 79.6% | 85 min | 1.6% | 364 |
| JetBlue | 78.4% | 98 min | 2.0% | 919 |
| Alaska Airlines | 78.1% | 67 min | 1.2% | 508 |
| Southwest Airlines | 32.8% | 71 min | 0.0% | 58 |
80%+ good 70–79.9% fair <70% poor
Best time of day to fly SAN to BOS
On-time arrival % by scheduled departure hour (local time), 3,458 flights over 24 months.
Show the numbers
| Departure hour | On time | Cancelled | Flights |
|---|---|---|---|
| 7am–8am | 87.3% | 0.0% | 80 |
| 8am–9am | 69.8% | 1.0% | 300 |
| 9am–10am | 73.5% | 0.8% | 265 |
| 10am–11am | 74.2% | 0.8% | 249 |
| 11am–12pm | 70.9% | 1.3% | 318 |
| 12pm–1pm | 74.7% | 0.0% | 83 |
| 1pm–2pm | 71.8% | 2.9% | 242 |
| 2pm–3pm | 54.5% | 0.7% | 146 |
| 3pm–4pm | 83.0% | 3.6% | 111 |
| 8pm–9pm | 79.3% | 0.6% | 632 |
| 9pm–10pm | 87.0% | 1.3% | 390 |
| 10pm–11pm | 78.5% | 1.4% | 642 |
Best day of the week
24 months, by day of departure.
Best month to fly
24 months, by calendar month.
Holiday travel on SAN 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) | 78.6% | +0.4 pts | 0.0% | 56 |
| Christmas & New Year (Dec 20 - Jan 3) | 65.8% | -12.4 pts | 3.2% | 126 |
| Summer peak (Jun 15 - Aug 15) | 71.3% | -6.9 pts | 1.3% | 760 |
| All other days | 78.2% | — | 1.1% | 2,516 |
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).