Resident Population in San Augustine County, TX was 7.76700 Thous. of Persons in January of 2024, according to the United States Federal Reserve. Historically, Resident Population in San Augustine County, TX reached a record high of 8.96100 in January of 1981 and a record low of 7.76700 in January of 2024. Trading Economics provides the current actual value, an historical data chart and related indicators for Resident Population in San Augustine County, TX - last updated from the United States Federal Reserve on April of 2026.