Sammamish is a city in King County, Washington, United States. The population was 45,780 at the 2010 census.
The Sammamish Plateau is part of unincorporated King County for most of its recorded history. The first Europeans arrived in the late 19th century and established a trio of resorts by the 1930s. The plateau remained a mostly rural area until suburban homes, shopping centers, and schools were built in the 1970s and 1980s. A vote in 1991 to join neighboring Issaquah failed, as did a vote on incorporation the following year. A renewed movement to become a city, born of frustration with development policies set by the county government, met with voter approval in 1998. Sammamish was officially incorporated on August 31, 1999.