Nye County is a county in the U.S. state of Nevada. As of the 2020 census, the population was 51,591. Its county seat is Tonopah. At 18,159 square miles, Nye is Nevada's largest county by area and the third-largest county in the contiguous United States, behind Coconino County of Arizona and San Bernardino County of California. Nye County comprises the Pahrump micropolitan statistical area, which is included in the Las Vegas-Henderson combined statistical area.