Resident Population in Oldham County, TX was 1.82300 Thous. of Persons in January of 2024, according to the United States Federal Reserve. Historically, Resident Population in Oldham County, TX reached a record high of 2.60000 in January of 1971 and a record low of 1.73600 in January of 2021. Trading Economics provides the current actual value, an historical data chart and related indicators for Resident Population in Oldham County, TX - last updated from the United States Federal Reserve on April of 2026.