About 1 in 3 DL 571 flights from Boston arrived 15+ minutes late, diverted or cancelled over the past year (36%); 1.7% were cancelled. The typical flight landed 1 minutes late.
DL 571: BOS → SAN
Scheduled to leave Boston at 5:10 p.m. local time. Over the past year it arrived on time 64% of the time (364 flights), in line with other DL flights on the route at that hour (64%). Last seen in the data Aug 31, 2026.
Month by month
By day of week
| Day | Flights | On time |
|---|---|---|
| Monday | 53 | 68% |
| Tuesday | 52 | 63% |
| Wednesday | 52 | 62% |
| Thursday | 51 | 67% |
| Friday | 52 | 58% |
| Saturday | 52 | 65% |
| Sunday | 52 | 65% |
Why it was late
All flights BOS → SAN · Connecting off DL 571? Check the risk
DL 571: SAN → BOS
Scheduled to leave San Diego at 9:54 p.m. local time. Over the past year it arrived on time 80% of the time (162 flights), better than other DL flights on the route at that hour (74%). Last seen in the data Aug 31, 2026.
Month by month
By day of week
| Day | Flights | On time |
|---|---|---|
| Monday | 22 | 77% |
| Tuesday | 24 | 83% |
| Wednesday | 24 | 79% |
| Thursday | 22 | 73% |
| Friday | 22 | 91% |
| Saturday | 26 | 85% |
| Sunday | 22 | 73% |
Why it was late
All flights SAN → BOS · Connecting off DL 571? Check the risk
Questions
How often is DL 571 from BOS to SAN late?
Delta Air Lines 571 from Boston, MA to San Diego, CA arrived 15 or more minutes late, was diverted or was cancelled on 36% of 364 scheduled flights between September 2025 and August 2026. 1.7% were cancelled.
How often is DL 571 from SAN to BOS late?
Delta Air Lines 571 from San Diego, CA to Boston, MA arrived 15 or more minutes late, was diverted or was cancelled on 20% of 162 scheduled flights between September 2025 and August 2026. 0.0% were cancelled.
Flight numbers change. Figures cover flights with this airline, number and route only. "Likely range" is the 95% interval for the true on-time rate given the number of flights. This is history, not live status: check Delta Air Lines for today's flight. Method.