Resident Population in Rockwall County, TX was 137.04400 Thous. of Persons in January of 2024, according to the United States Federal Reserve. Historically, Resident Population in Rockwall County, TX reached a record high of 137.04400 in January of 2024 and a record low of 7.04600 in January of 1970. Trading Economics provides the current actual value, an historical data chart and related indicators for Resident Population in Rockwall County, TX - last updated from the United States Federal Reserve on April of 2026.