Kirkland is a city in King County, Washington, United States. It is a suburb of Seattle on the Eastside of Lake Washington. The population was 48,787 at the 2010 census, which made it the 9th largest city in King County and the 20th largest city in the state. Effective June 1, 2011, Kirkland added approximately 33,000 residents by annexation, making it the 6th largest city in King County and the 12th largest in the state.
Features of the city include the unique downtown waterfront (the only Eastside downtown frontage along Lake Washington's shoreline), with restaurants, art galleries, a 400 seat performing arts center, public parks, including beaches, and a collection of public art, primarily bronze sculptures.
Kirkland is the former home of the Seattle Seahawks; the NFL team's headquarters and training facility were located in Kirkland for its first 32 seasons. The Seahawks moved to the new 19-acre (77,000 m2) Virginia Mason Athletic Center in Renton on August 18, 2008. Warehouse chain Costco previously had its headquarters in Kirkland (now in Issaquah); the city is the namesake of its "Kirkland Signature" store brand. Google has a development office in Kirkland; see List of companies based in Kirkland, Washington.