Alaska Airlines SEA to BOS on-time performance
Alaska Airlines nonstop flights from Seattle to Boston · Aug 2025 – Jul 2026
On-time arrivals
75%
arrived < 15 min late
Cancelled
1.0%
12 flights
Avg arrival delay
13 min
49 min when late
Rank on route
#2 of 3
route average 75% on time
Key facts
- Alaska Airlines flights on SEA to BOS arrived on time 75% of the time in Aug 2025 – Jul 2026.
- 1% were cancelled, and 6% arrived an hour or more late.
- That ranks #2 of 3 airlines on this route, which averaged 75% on time overall.
- The largest source of delay minutes was air traffic control & airport congestion (49%).
On-time trend by month
Why this airline's flights were late
- Air traffic control & airport congestion49%
- Late-arriving aircraft23%
- Airline (crew, maintenance, cleaning, fueling)20%
- Extreme weather8%
- Security0%
Other airlines on SEA to BOS
- Delta Air Lines80% on time · 15 min avg delay
- JetBlue53% on time · 42 min avg delay
Full SEA to BOS comparison →
Alaska Airlines on-time record across all routes →
1,221 Alaska Airlines flights tracked on this route; 12 cancelled, 3 diverted.
Data: U.S. DOT Bureau of Transportation Statistics, Aug 2025 – Jul 2026 (12 months). Latest month published by BTS: July 2026. How we calculate this.