About 1 in 6 DL 429 flights from Seattle arrived 15+ minutes late, diverted or cancelled over the past year (17%); 4.1% were cancelled. The typical flight landed 10 minutes early.
DL 429: SEA → JFK
Scheduled to leave Seattle at 7:15 a.m. local time. Over the past year it arrived on time 83% of the time (365 flights), in line with other DL flights on the route at that hour (83%). Last seen in the data Aug 31, 2026.
Month by month
By day of week
| Day | Flights | On time |
|---|---|---|
| Monday | 53 | 79% |
| Tuesday | 52 | 85% |
| Wednesday | 52 | 94% |
| Thursday | 52 | 88% |
| Friday | 52 | 81% |
| Saturday | 52 | 79% |
| Sunday | 52 | 77% |
Why it was late
All flights SEA → JFK · Connecting off DL 429? Check the risk
Questions
How often is DL 429 from SEA to JFK late?
Delta Air Lines 429 from Seattle, WA to New York, NY arrived 15 or more minutes late, was diverted or was cancelled on 17% of 365 scheduled flights between September 2025 and August 2026. 4.1% 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.