Spring Valley is an unincorporated town and census-designated place in Clark County, Nevada, United States, located 2 miles (3 km) west of the Las Vegas Strip. The population was 215,597 at the 2020 census. Spring Valley was formed in May 1981.

Clark County is a county located in the U.S. state of Nevada. The land area of Clark County is 8,061 square miles (20,880 km2), or roughly the size of New Jersey. As of the 2020 census, the population was 2,265,461. Most of the county population resides in the Las Vegas Census County Divisions, which has 2,196,623 people as of the 2020 Census. It is by far the most populous county in Nevada, and the 11th-most populous county in the United States. It covers 7% of the state's land area but holds 73% of the state's population, making Nevada the most centralized state in the United States.