San Francisco International ⇄ Seattle-Tacoma International SFO–SEA
Airlines flew 13,502 flights between San Francisco International SFO in San Francisco, CA and Seattle-Tacoma International SEA in Seattle, WA in the twelve months to July 2026, both directions together: 1,629,507 passengers in 1,976,288 seats, 82% of them filled, and 2,680,746 pounds of freight. 679 miles, about 98 minutes in the air, on 8 airlines: Alaska Airlines Inc. (5,356), United Air Lines Inc. (4,083), SkyWest Airlines Inc. (2,128), Delta Air Lines Inc. (1,911) and 4 more. Planning to fly it yourself? The weather and winds along this route right now.
Flights by month both directions
By month, as a table
| flights | |
|---|---|
| 1/25 | 1,054 |
| 2/25 | 954 |
| 3/25 | 1,123 |
| 4/25 | 1,080 |
| 5/25 | 1,268 |
| 6/25 | 1,263 |
| 7/25 | 1,260 |
| 8/25 | 1,236 |
| 9/25 | 1,165 |
| 10/25 | 1,158 |
| 11/25 | 1,118 |
| 12/25 | 1,115 |
| 1/26 | 960 |
| 2/26 | 963 |
| 3/26 | 1,029 |
| 4/26 | 993 |
| 5/26 | 1,177 |
| 6/26 | 1,261 |
| 7/26 | 1,327 |
Passengers by month
By month, as a table
| passengers | |
|---|---|
| 1/25 | 112,253 |
| 2/25 | 105,065 |
| 3/25 | 120,030 |
| 4/25 | 125,135 |
| 5/25 | 145,117 |
| 6/25 | 150,456 |
| 7/25 | 160,314 |
| 8/25 | 162,090 |
| 9/25 | 142,153 |
| 10/25 | 135,888 |
| 11/25 | 129,672 |
| 12/25 | 130,770 |
| 1/26 | 111,157 |
| 2/26 | 112,907 |
| 3/26 | 122,433 |
| 4/26 | 121,651 |
| 5/26 | 138,326 |
| 6/26 | 155,162 |
| 7/26 | 167,298 |
The airlines twelve months, both directions
| Airline | Flights | Passengers | Seats filled | Service |
|---|---|---|---|---|
| Alaska Airlines Inc. AS | 5,356 | 776,963 | 84% | scheduled passenger service |
| United Air Lines Inc. UA | 4,083 | 524,284 | 82% | scheduled passenger service |
| SkyWest Airlines Inc. OO | 2,128 | 137,935 | 88% | scheduled passenger service |
| Delta Air Lines Inc. DL | 1,911 | 188,883 | 73% | charter passenger service, scheduled passenger service |
| Horizon Air QX | 14 | 884 | 83% | scheduled passenger service |
| Southwest Airlines Co. WN | 7 | 556 | 45% | scheduled passenger service |
| Scott Aviation, LLC d/b/a Silver Air 3EQ | 2 | 2 | 14% | charter passenger service |
| Air Transport International 8C | 1 | 0 | charter cargo service |
The aircraft as the airlines report their types
| Aircraft | Flights | Seats a flight | Passengers |
|---|---|---|---|
| Boeing 737-900ER | 2,370 | 178 | 344,024 |
| Boeing B737 Max 900 | 2,196 | 178 | 327,277 |
| Embraer ERJ-175 | 2,142 | 74 | 138,819 |
| Boeing 737-800 | 2,131 | 162 | 280,676 |
| Airbus Industrie A320-100/200 | 1,573 | 150 | 193,207 |
| Boeing B737 Max 800 | 847 | 165 | 117,025 |
| A220-300 BD-500-1A11 | 785 | 130 | 79,421 |
| Airbus Industrie A319 | 631 | 126 | 67,801 |
| A200-100 BD-500-1A10 | 561 | 109 | 52,149 |
| Boeing 737-700/700LR/Max 7 | 116 | 124 | 12,677 |
| Airbus Industrie A321Neoxlr | 62 | 189 | 6,658 |
| Airbus Industrie A321-200n | 50 | 198 | 5,946 |
| Boeing 737-900 | 19 | 178 | 3,018 |
| Boeing 757-200 | 14 | 81 | 523 |
| Cessna Citation X Model 650/550B/550XL | 2 | 7 | 2 |
| Boeing 767-300/300ER | 1 | 0 | 0 |
| Boeing 757-300 | 1 | 234 | 71 |
| Boeing 777-300/300ER/333ER | 1 | 350 | 213 |
SFO → SEA this direction alone · flown January 2025 to July 2026
6,747 flights of 6,817 scheduled, 815,385 passengers in 986,051 seats, 827,039 pounds of freight, 159,562 pounds of mail. Alaska Airlines Inc. 2,675; United Air Lines Inc. 2,047; SkyWest Airlines Inc. 1,065; Delta Air Lines Inc. 946; Horizon Air 9; Southwest Airlines Co. 3; Scott Aviation, LLC d/b/a Silver Air 1; Air Transport International 1.
SEA → SFO this direction alone · flown January 2025 to July 2026
6,755 flights of 6,828 scheduled, 814,122 passengers in 990,237 seats, 1,853,707 pounds of freight, 55,935 pounds of mail. Alaska Airlines Inc. 2,681; United Air Lines Inc. 2,036; SkyWest Airlines Inc. 1,063; Delta Air Lines Inc. 965; Horizon Air 5; Southwest Airlines Co. 4; Scott Aviation, LLC d/b/a Silver Air 1.
Source: the Bureau of Transportation Statistics' T-100 Segment table (all carriers). A flight is one departure performed on this segment; seats and passengers are the airlines' own monthly reports; "seats filled" is passengers divided by seats. The miles are the DOT's great-circle distance. Both ends: San Francisco International SFO and Seattle-Tacoma International SEA; all routes.