What airport is SEA?

Why the code is SEA

The first three letters of Seattle.

The airport authority or a contemporaneous record states this directly.

The airport

IATA code

SEA

ICAO code

KSEA

Airport

Seattle-Tacoma International Airport

City

Seattle, United States

Opened

1944

Code origin

Documented

It was built during the war after the military took over Boeing Field, and the Port of Seattle placed it between Seattle and Tacoma so both cities would fund it — hence the hyphenated name that nobody uses. Everyone calls it Sea-Tac, including the city that grew up around it and formally took that name in 1990.

The other code, KSEA

Every airport has two codes. The three-letter IATA code, SEA, is the one on your boarding pass and your luggage tag, and it is assigned for commercial use. The four-letter ICAO code, KSEA, is the one pilots and controllers use, and it is assigned geographically: the first letter or two identify the region, so every airport in the same part of the world shares a prefix. That is why KSEA looks nothing like SEA.