Seattle (SEA) to Boston (BOS) flights
Alaska Airlines, Delta Air Lines, JetBlue fly nonstop from Seattle-Tacoma International Airport to Boston Logan International Airport, with about 69 flights a week in July 2026. The 2,496-mile flight takes about 5h 17m gate to gate.
- Distance
- 2,496 mi · 4,017 km
- Flight time
- 5h 17m
- Airlines
- 3
- Seats filled
- 87%
Airlines flying SEA to BOS
| Airline | Flights a week | Aircraft | Passengers (12 months) | Flight time |
|---|---|---|---|---|
| Alaska Airlines | 31 | Boeing 737-900ER, Boeing 737 MAX 9, Boeing 737-800 | 189,641 | 5h 17m |
| Delta Air Lines | 25 | Airbus A321, Boeing 737-800, Boeing 737-900ER | 166,065 | 5h 17m |
| JetBlue | 13 | Airbus A321, Airbus A320-100/200 | 40,740 | 5h 20m |
Airlines are the operating carrier: regional airlines such as SkyWest or Horizon often fly under a larger airline's brand.
SEA to BOS flight schedule
14 flight numbers flew this route in August 2026, 8 of them almost daily. The first usually leaves at 6:00am and the last at 11:45pm. Times are local and can change; check with the airline before you book.
| Flight | Departs | Arrives | Days flown in August 2026 | On time (12 months) |
|---|---|---|---|---|
| AS 476Alaska Airlines | 6:00am | 2:28pm | 8 | n/a |
| AS 1505Alaska Airlines | 6:03am | 2:23pm | 13 | 97% |
| DL 459Delta Air Lines | 7:38am | 4:10pm | 31 | 88% |
| AS 357Alaska Airlines | 8:00am | 4:38pm | 13 | 100% |
| AS 306Alaska Airlines | 8:23am | 4:53pm | 31 | 76% |
| AS 219Alaska Airlines | 10:13am | 6:41pm | 18 | 62% |
| DL 438Delta Air Lines | 11:15am | 7:43pm | 31 | 56% |
| B6 398JetBlue | 11:40am | 8:09pm | 31 | 44% |
| AS 460Alaska Airlines | 3:36pm | 11:59pm | 31 | 82% |
| DL 474Delta Air Lines | 3:59pm | 12:17am | 25 | 67% |
| AS 214Alaska Airlines | 11:06pm | 7:39am | 13 | 79% |
| DL 473Delta Air Lines | 11:13pm | 7:35am | 31 | 84% |
| AS 536Alaska Airlines | 11:18pm | 7:40am | 14 | 78% |
| B6 198JetBlue | 11:45pm | 8:04am | 31 | 41% |
Is SEA to BOS on time?
From September 2025 to August 2026, 75% of 2,554 flights arrived within 15 minutes of schedule and 1.5% were cancelled. Flights leaving around 7am were the most punctual (89%), those around 11am the least (51%). Most delay time was caused by air traffic control and airport congestion (41%).
| Airline | Flights | On time | Average delay | Cancelled |
|---|---|---|---|---|
| Alaska Airlines | 1,240 | 78% | 13 min | 1.1% |
| Delta Air Lines | 1,067 | 80% | 15 min | 1.7% |
| JetBlue | 247 | 43% | 45 min | 2.4% |
Airlines as sold: flights operated by regional partners count under the airline on the ticket. Average delay is across all completed flights, early arrivals counted as zero.
On-time arrivals by departure time
| Scheduled departure | Flights | On time, relative | On time |
|---|---|---|---|
| 7am to 8am | 443 | 89% | |
| 8am to 9am | 238 | 75% | |
| 9am to 10am | 101 | 75% | |
| 10am to 11am | 128 | 58% | |
| 11am to 12pm | 225 | 51% | |
| 3pm to 4pm | 517 | 77% | |
| 4pm to 5pm | 74 | 70% | |
| 10pm to 11pm | 308 | 80% | |
| 11pm to 12am | 426 | 74% |
Flights by month
| Month | Flights | Flights, relative | Passengers |
|---|---|---|---|
| August 2025 | 268 | 47,697 | |
| September 2025 | 229 | 38,589 | |
| October 2025 | 225 | 35,853 | |
| November 2025 | 158 | 23,413 | |
| December 2025 | 160 | 23,220 | |
| January 2026 | 121 | 19,068 | |
| February 2026 | 122 | 17,698 | |
| March 2026 | 171 | 27,256 | |
| April 2026 | 171 | 27,330 | |
| May 2026 | 253 | 39,869 | |
| June 2026 | 274 | 45,090 | |
| July 2026 | 307 | 51,363 |
Related
Source: US Department of Transportation, T-100 Segment data, August 2025 to July 2026.