Resident Population in Castro County, TX was 7.22700 Thous. of Persons in January of 2023, according to the United States Federal Reserve. Historically, Resident Population in Castro County, TX reached a record high of 10.55600 in January of 1980 and a record low of 7.11300 in January of 2008. Trading Economics provides the current actual value, an historical data chart and related indicators for Resident Population in Castro County, TX - last updated from the United States Federal Reserve on May of 2024.