About 6 in 10 B6 398 flights from Seattle arrived 15+ minutes late, diverted or cancelled over the past year (56%); 1.2% were cancelled. The typical flight landed 18 minutes late.
B6 398: SEA → BOS
Scheduled to leave Seattle at 11:45 a.m. local time. Over the past year it arrived on time 44% of the time (165 flights), better than other B6 flights on the route at that hour (38%). Last seen in the data Aug 31, 2026.
Month by month
By day of week
| Day | Flights | On time |
|---|---|---|
| Monday | 24 | 33% |
| Tuesday | 23 | 48% |
| Wednesday | 23 | 39% |
| Thursday | 24 | 42% |
| Friday | 24 | 42% |
| Saturday | 24 | 63% |
| Sunday | 23 | 39% |
Why it was late
All flights SEA → BOS · Connecting off B6 398? Check the risk
Questions
How often is B6 398 from SEA to BOS late?
JetBlue 398 from Seattle, WA to Boston, MA arrived 15 or more minutes late, was diverted or was cancelled on 56% of 165 scheduled flights between September 2025 and August 2026. 1.2% 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 JetBlue for today's flight. Method.