Salt Flat is a ghost town in northeastern Hudspeth County, Texas, United States. It lies along the concurrent U.S. Routes 62 and 180, north of the Census-designated place of Sierra Blanca, the county seat of Hudspeth County. Its elevation is 3,730 feet. Although Salt Flat is unincorporated, it has a ZIP Code of 79847. The headquarters of the nearby Guadalupe Mountains National Park uses this ZIP Code, although it is located closer to Pine Springs, which has no post office.