About 1 in 11 DL 1421 flights from Los Angeles arrived 15+ minutes late, diverted or cancelled over the past year (9%); 3.4% were cancelled. The typical flight landed 13 minutes early.
DL 1421: LAX → SFO
Scheduled to leave Los Angeles at 7:00 a.m. local time. Over the past year it arrived on time 91% of the time (352 flights), in line with other DL flights on the route at that hour (93%). Last seen in the data Aug 31, 2026.
Month by month
By day of week
| Day | Flights | On time |
|---|---|---|
| Monday | 53 | 94% |
| Tuesday | 52 | 92% |
| Wednesday | 52 | 94% |
| Thursday | 52 | 88% |
| Friday | 50 | 84% |
| Saturday | 43 | 91% |
| Sunday | 50 | 92% |
Why it was late
All flights LAX → SFO · Connecting off DL 1421? Check the risk
DL 1421: SFO → LAX
Scheduled to leave San Francisco at 8:55 a.m. local time. Over the past year it arrived on time 86% of the time (352 flights), in line with other DL flights on the route at that hour (87%). Last seen in the data Aug 31, 2026.
Month by month
By day of week
| Day | Flights | On time |
|---|---|---|
| Monday | 53 | 91% |
| Tuesday | 52 | 90% |
| Wednesday | 52 | 90% |
| Thursday | 52 | 83% |
| Friday | 51 | 78% |
| Saturday | 42 | 88% |
| Sunday | 50 | 84% |
Why it was late
All flights SFO → LAX · Connecting off DL 1421? Check the risk
Questions
How often is DL 1421 from LAX to SFO late?
Delta Air Lines 1421 from Los Angeles, CA to San Francisco, CA arrived 15 or more minutes late, was diverted or was cancelled on 9% of 352 scheduled flights between September 2025 and August 2026. 3.4% were cancelled.
How often is DL 1421 from SFO to LAX late?
Delta Air Lines 1421 from San Francisco, CA to Los Angeles, CA arrived 15 or more minutes late, was diverted or was cancelled on 14% of 352 scheduled flights between September 2025 and August 2026. 3.7% 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.