El Dorado Hills is an unincorporated town and census-designated place in El Dorado County, California. Located in the Greater Sacramento region of Northern California, it had a population of 50,547 at the 2020 census, up from 42,108 at the 2010 census.

El Dorado County, officially the County of El Dorado, is a county located in the U.S. state of California. As of the 2020 census, the population was 191,185. The county seat is Placerville. The county is part of the Sacramento-Roseville-Arden-Arcade, CA Metropolitan Statistical Area. It is located entirely in the Sierra Nevada, from the historic Gold Country in the western foothills to the High Sierra in the east. El Dorado County's population has grown as Greater Sacramento has expanded into the region. Where the county line crosses US 50 at Clarksville, the distance to Sacramento is 15 miles. In the county's high altitude eastern end at Lake Tahoe, environmental awareness and environmental protection initiatives have grown along with the population since the 1960 Winter Olympics, hosted at the former Squaw Valley Ski Resort in neighboring Placer County.