Tonopah /ˈtoʊnoʊˌpɑː/ is an unincorporated community and census-designated place (CDP) in western Maricopa County, Arizona, United States, 52 miles (84 km) west of downtown Phoenix off Interstate 10.

In 2009, a political action committee named Tonopah United for Our Future (TUFF) filed paperwork with the county, proposing the incorporation of the area into a town.

In 2003, Buckeye had passed a measure approving of any future incorporation effort by Tonopah, but the town council rescinded the measure, citing concerns that the proposal would extend the new town's boundaries east of the Hassayampa River and into area Buckeye intends to annex.

Additionally, a number of residents opposed the plan because they believed large tax increases would be necessary to fund a new government.

At the time, Gates's company announced plans to create a "smart city" called Belmont on the site.