Route profile
BOS→SAN
Flight reliability, delays and best times to fly from Boston to San Diego, 2,588 miles.
Right now
Aviation weather is not currently a factor.
Aviation weather is not currently a factor.
Route reliability
July 2023 – July 2026
Better than 57% of comparable major US routes (4,598 compared)
Calculated from 5,087 flights. How this is calculated
BOS → SAN arrives on time 76.4% of the time; the return trip, SAN → BOS, arrives on time 75.5% of the time.
BOS → SAN spends 31.0 minutes on the ground on a 2,588-mile trip: 23.5 minutes from pushback to wheels-up at BOS and 7.4 minutes from touchdown to gate at SAN.
Source: US DOT Bureau of Transportation Statistics · Data covering July 2023 – July 2026
What sets this route apart
Where BOS to SAN differs most from similar routes by hour, weekday, month and airline, July 2023 – July 2026.
BOS to SAN is at its best against routes of similar length for flights scheduled at 10 AM: 85.0% arrive on time, 7.7 points ahead of the 77.3% those routes manage at that hour.
Saturday is the day BOS to SAN slips furthest against routes of similar length, 71.5% on time where they average 78.7%, 7.2 points lower. Against all other routes the gap is 7.6 points.
In September, BOS to SAN runs 9.3 points below routes of similar length, 72.3% on time to 81.6%. Against all other routes the gap is 10.1 points.
March is kinder to BOS to SAN than to routes of similar length: 85.0% on time against 79.1%, 5.9 points better. Against all other routes the gap is 7.1 points.
Delta Air Lines’ flights on BOS to SAN arrive on time 71.2% of the time, 9.3 points below the 80.5% it manages on its routes of similar length. Against all other routes the gap is 10.3 points.
BOS to SAN against comparable routes
July 2023 – July 2026| Measure | This route | Compared with | Them | Gap | Flights behind it |
|---|---|---|---|---|---|
| Hour: 10 AM departures | 85.0% | routes of similar length | 77.3% | +7.7 pts | 167 here, 41,181 there |
| Weekday: Saturday | 71.5% | routes of similar length | 78.7% | −7.2 pts | 599 here, 113,951 there |
| Month: September | 72.3% | routes of similar length | 81.6% | −9.3 pts | 365 here, 68,233 there |
| Month: March | 85.0% | routes of similar length | 79.1% | +5.9 pts | 386 here, 66,587 there |
| Airline: Delta Air Lines | 71.2% | routes of similar length | 80.5% | −9.3 pts | 1,102 here, 136,831 there |
Each comparison pools the flights of other routes, with this route’s own left out. Similar length means within 15% of this route’s 2,588 miles, with at least 5 such routes. A bucket is set against the most comparable group that has enough flights: similar length, then the same origin (at least 3 routes), then all other routes. Hours, weekdays and months appear only where both sides have 120 completed flights, and airlines where both have 600. The gap must be at least 2 points and 2 standard errors, and only the largest gap each way is kept per measure. These are differences in the flights counted, not causes.
When it goes wrong
July 2023 – July 2026
41 min late
against a median of 7 min early
Percentiles over 5,087 operations; cancelled and diverted flights are counted separately.
Will your connection be tight enough?
Layovers at SAN after arriving from BOS.
| Connection time | Chance of missing | Reads as |
|---|---|---|
| 30 min | 39% | Likely to miss |
| 45 min | 23% | High risk |
| 60 min | 14% | Some risk |
| 90 min | 6.7% | Some risk |
| 120 min | 3.6% | Low risk |
This is one leg of a connection. Gate changes and the next flight's own schedule matter too. And a connection can fail before delay is even the question — this route cancels 0.90% of the time and diverts 0.63% of the time, which a late arrival never shows up in.
Chance of missing is the share of 5,009 arrivals on this route that landed later than the connection time less 30 minutes to reach the next gate.
The worst tenth of arrivals on this route land at least 41 minutes late (90th-percentile gate arrival delay), over 5,087 operations.
Any other layover length: connection checker.
Best time to fly
BOS → SAN flights departing 9 AM–12 PM arrived on time 83.7% of the time, against 62.0% for 6–9 PM departures, a gap of 21.7 percentage points.
By departure window
By departure hour
- 12 AM to 5 AM: too few flights to score
- 6 AM: 83.7% on time from 410 flights
- 7 AM: 83.6% on time from 499 flights
- 8 AM: 79.2% on time from 418 flights
- 9 AM: 83.1% on time from 299 flights
- 10 AM: 85.0% on time from 169 flights
- 11 AM to 2 PM: too few flights to score
- 3 PM: 78.0% on time from 618 flights
- 4 PM: 75.0% on time from 1,041 flights
- 5 PM: 70.7% on time from 1,442 flights
- 6 PM: 62.0% on time from 180 flights
- 7 PM to 11 PM: too few flights to score
Why BOS → SAN runs late
July 2023 – July 2026
airspace and airport capacity, including weather-driven flow control
crew, maintenance, boarding and fueling, all within the carrier’s control
the inbound aircraft was late, so this flight started late
weather severe enough to stop this flight specifically
screening or terminal security incidents
Share of the delay minutes US DOT attributed to each cause for BOS → SAN. Only delays of 15 minutes or more are attributed.
Airlines on this route
Carriers with at least 200 flights, by the airline that operated each one.
| Carrier | Flights | On time | Cancelled | Median delay | Severe |
|---|---|---|---|---|---|
| JetBlue | 2,514 | 81.3% | 0.80% | -10 min | 6.3% |
| Alaska Airlines | 1,390 | 73.0% | 1.01% | -4 min | 8.3% |
| Delta Air Lines | 1,124 | 71.2% | 0.89% | -2 min | 5.5% |
JetBlue flew 50.0% of the 5,028 flights listed.
JetBlue arrived on time 10.1 percentage points more often than Delta Air Lines on this route.
Flights on this route
Flight numbers with at least 600 operations here and still on the schedule.
B6619 (6:00 AM) arrived on time 82.7% of the time, 11.5 points more often than AS389 (4:36 PM) at 71.2%.
Weekly and seasonal patterns
By day of week
Monday is historically the most reliable day and Saturday the least, a gap of 7.7 percentage points.
By month
- Jan: 81.6%
- Feb: 73.7%
- Mar: 85.0%
- Apr: 76.1%
- May: 80.0%
- Jun: 73.4%
- Jul: 72.8%
- Aug: 72.3%
- Sep: 72.3%
- Oct: 74.1%
- Nov: 79.6%
- Dec: 80.1%
August is historically the weakest month and March the strongest, a spread of 12.7 percentage points.
Reliability over time
July 2023 – July 2026
- July 2023: too few flights to score (119)
- August 2023: 63.1% from 123 flights
- September 2023: 67.5% from 120 flights
- October 2023: 68.5% from 147 flights
- November 2023: 75.2% from 126 flights
- December 2023: too few flights to score (116)
- January 2024: too few flights to score (88)
- February 2024: too few flights to score (95)
- March 2024: too few flights to score (117)
- April 2024: too few flights to score (116)
- May 2024: 74.5% from 158 flights
- June 2024: 72.5% from 149 flights
- July 2024: 69.1% from 155 flights
- August 2024: 69.3% from 142 flights
- September 2024: too few flights to score (116)
- October 2024: 75.4% from 141 flights
- November 2024: too few flights to score (112)
- December 2024: 75.4% from 122 flights
- January 2025: too few flights to score (117)
- February 2025: too few flights to score (104)
- March 2025: 87.5% from 121 flights
- April 2025: too few flights to score (117)
- May 2025: 84.1% from 164 flights
- June 2025: 82.6% from 172 flights
- July 2025: 75.4% from 181 flights
- August 2025: 81.1% from 176 flights
- September 2025: 71.5% from 135 flights
- October 2025: 78.0% from 163 flights
- November 2025: 81.6% from 137 flights
- December 2025: 76.6% from 133 flights
- January 2026: 72.1% from 120 flights
- February 2026: too few flights to score (112)
- March 2026: 82.6% from 151 flights
- April 2026: 77.8% from 144 flights
- May 2026: 81.0% from 163 flights
- June 2026: 66.3% from 203 flights
- July 2026: 78.0% from 212 flights
Over the most recent 12 months (2025-08 to 2026-07), on-time arrivals averaged 76.7% against 78.6% in the 12 months before — declining by 1.9 percentage points.
Data and methodology
Calculated by FlyerIntel from 5,087 BOS → SAN flight records from the US DOT Bureau of Transportation Statistics, covering July 2023 – July 2026. Late means 15 or more minutes past scheduled arrival; cancelled and diverted flights are left out of on-time rates.
Full methodology · Data sources · Report a problem
Related research: How Long a Layover Needs to Be · Two Airlines on One Route · Best Time of Day to Fly From Major US Airports
Analysis last recomputed