Renton is a city in King County, Washington, United States, and an inner-ring suburb of Seattle. Situated 11 miles (18 km) southeast of downtown Seattle, Renton straddles the southeast shore of Lake Washington, at the mouth of the Cedar River. As of the 2020 census, the population of Renton was 106,785, up from 90,927 at the 2010 census. The city is currently the 6th most populous municipality in greater Seattle and the 8th most populous city in Washington.