Population Estimate, Total, Hispanic or Latino (5-year estimate) in Williamson County, TX was 154605.00000 Persons in January of 2022, according to the United States Federal Reserve. Historically, Population Estimate, Total, Hispanic or Latino (5-year estimate) in Williamson County, TX reached a record high of 154605.00000 in January of 2022 and a record low of 77631.00000 in January of 2009. Trading Economics provides the current actual value, an historical data chart and related indicators for Population Estimate, Total, Hispanic or Latino (5-year estimate) in Williamson County, TX - last updated from the United States Federal Reserve on May of 2024.