Seattle (SEA) to Baltimore (BWI) flights
Alaska Airlines, Southwest Airlines fly nonstop from Seattle-Tacoma International Airport to Baltimore/Washington International Thurgood Marshall Airport, with about 21 flights a week in July 2026. The 2,335-mile flight takes about 4h 54m gate to gate.
- Distance
- 2,335 mi · 3,758 km
- Flight time
- 4h 54m
- Airlines
- 2
- Seats filled
- 88%
Airlines flying SEA to BWI
| Airline | Flights a week | Aircraft | Passengers (12 months) | Flight time |
|---|---|---|---|---|
| Alaska Airlines | 14 | Boeing 737-900ER, Boeing 737 MAX 9, Boeing 737-800 | 91,604 | 4h 55m |
| Southwest Airlines | 7 | Boeing 737-800, Boeing 737 MAX 8 | 19,871 | 4h 52m |
Airlines are the operating carrier: regional airlines such as SkyWest or Horizon often fly under a larger airline's brand.
SEA to BWI flight schedule
3 flight numbers flew this route in August 2026, 3 of them almost daily. The first usually leaves at 9:03am and the last at 10:30pm. 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 378Alaska Airlines | 9:03am | 5:04pm | 31 | 84% |
| AS 781Alaska Airlines | 10:22pm | 6:27am | 31 | 85% |
| WN 3525Southwest Airlines | 10:30pm | 6:30am | 28 | 63% |
Is SEA to BWI on time?
From September 2025 to August 2026, 81% of 719 flights arrived within 15 minutes of schedule and 0.7% were cancelled. Flights leaving around 9am were the most punctual (86%), those around 9pm the least (77%). Most delay time was caused by the airline (crew, maintenance, cleaning, fuelling) (42%).
| Airline | Flights | On time | Average delay | Cancelled |
|---|---|---|---|---|
| Alaska Airlines | 599 | 85% | 7 min | 0.7% |
| Southwest Airlines | 120 | 61% | 17 min | 0.8% |
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 |
|---|---|---|---|
| 9am to 10am | 201 | 86% | |
| 10am to 11am | 164 | 82% | |
| 9pm to 10pm | 237 | 77% | |
| 10pm to 11pm | 117 | 77% |
Flights by month
| Month | Flights | Flights, relative | Passengers |
|---|---|---|---|
| August 2025 | 93 | 15,250 | |
| September 2025 | 90 | 14,350 | |
| October 2025 | 56 | 8,370 | |
| November 2025 | 50 | 7,191 | |
| December 2025 | 60 | 8,707 | |
| January 2026 | 34 | 4,821 | |
| February 2026 | 27 | 3,908 | |
| March 2026 | 31 | 5,048 | |
| April 2026 | 38 | 5,719 | |
| May 2026 | 58 | 8,770 | |
| June 2026 | 88 | 14,036 | |
| July 2026 | 94 | 15,340 |
Related
Source: US Department of Transportation, T-100 Segment data, August 2025 to July 2026.