Route Reliability
Seattle → Boston
SEA–BOS · 2,496 miles · Seattle–Tacoma International Airport to Boston Logan International Airport
- 75%
- Arrive within 15 minutes
- 9 min
- Average arrival delay
- 1.1%
- Cancelled
- 2,436
- Flights in the data
Data through May 2026.
Who flies it best
Ranked by on-time arrivals. Historical results, not predictions.
- 1.Delta Air Lines83%978 flights
- 2.Alaska Airlines73%1,210 flights
- 3.JetBlue Airways58%248 flights
What the data says
The 6–9 AM departure wins.
SEA–BOS flights departing between 6–9 AM arrived on time 83% of the time, versus 61% between 9 AM–12 PM.
Sunday scaries are real for this one.
SEA–BOS flights arrived on time 80% of the time on Tuesdays. On Sundays: 72%.
Delta Air Lines has a clear lead on this route.
Delta Air Lines arrived on time 83% of the time on this route; JetBlue Airways managed 58%.
Best historical flights
Ranked by on-time arrivals, minimum 100 flights. Past performance, not a promise.
Top flights by on-time rate
More flights on this route
The breakdown
- Mon76%(344 flights)
- Tue80%(337 flights)
- Wed77%(344 flights)
- Thu74%(353 flights)
- Fri74%(353 flights)
- Sat75%(317 flights)
- Sun72%(350 flights)
- 6–9 AM83%(667 flights)
- 9 AM–12 PM61%(389 flights)
- 12–3 PM80%(25 flights)
- 3–6 PM78%(577 flights)
- 9 PM–12 AM75%(740 flights)
Jun 71% → May 83% on time
| Month | On-time percentage | Flights |
|---|---|---|
| June 2025 | 71% | 253 |
| July 2025 | 60% | 269 |
| August 2025 | 66% | 268 |
| September 2025 | 70% | 229 |
| October 2025 | 73% | 225 |
| November 2025 | 83% | 157 |
| December 2025 | 87% | 159 |
| January 2026 | 86% | 121 |
| February 2026 | 82% | 122 |
| March 2026 | 88% | 171 |
| April 2026 | 78% | 171 |
| May 2026 | 83% | 253 |
Keep nerding
Based on 2,436 historical flights, because apparently we checked. Historical flight data: U.S. Bureau of Transportation Statistics, June 2025 – May 2026. Data through May 2026. How we calculate this.