SeaTac is a city in southern King County, Washington, United States. The city is an inner-ring suburb of Seattle and part of the Seattle metropolitan area. The name "SeaTac" is derived from the Seattle–Tacoma International Airport, itself a portmanteau of Seattle and Tacoma.

Horizon Air is a regional airline in the United States headquartered in SeaTac, Washington, within the Seattle metropolitan area. It is a wholly-owned subsidiary of the Alaska Air Group and it is paid by fellow group member Alaska Airlines to staff, operate and maintain aircraft used on flights that are scheduled, marketed and sold by Alaska Airlines. Planes operated by Horizon are co-branded as Alaska HORIZON in order to differentiate Horizon's planes from those operated by Alaska's other regional airline partner, SkyWest Airlines.