About 1 in 3 DL 474 flights from Seattle arrived 15+ minutes late, diverted or cancelled over the past year (35%); 1.8% were cancelled. The typical flight landed 4 minutes late.
DL 474: SEA → BOS
Scheduled to leave Seattle at 4:00 p.m. local time. Over the past year it arrived on time 65% of the time (228 flights), in line with other DL flights on the route at that hour (65%). Last seen in the data Aug 30, 2026.
Month by month
By day of week
| Day | Flights | On time |
|---|---|---|
| Monday | 39 | 64% |
| Tuesday | 35 | 71% |
| Wednesday | 34 | 68% |
| Thursday | 38 | 63% |
| Friday | 38 | 68% |
| Saturday | 5 | — |
| Sunday | 39 | 51% |
Why it was late
All flights SEA → BOS · Connecting off DL 474? Check the risk
Questions
How often is DL 474 from SEA to BOS late?
Delta Air Lines 474 from Seattle, WA to Boston, MA arrived 15 or more minutes late, was diverted or was cancelled on 35% of 228 scheduled flights between September 2025 and August 2026. 1.8% 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.