Rockwall is a city in Rockwall County, Texas, United States, that is part of the Dallas/Fort Worth metroplex. It is the county seat of Rockwall County. The U.S. Census Bureau estimates that as of the 2020 census, Rockwall's population is 47,251, up from 45,888 in 2019. The name Rockwall is derived from a naturally jointed geological formation, which has the appearance of an artificial wall.