Resident Population in Jefferson County, OH was 64.02600 Thous. of Persons in January of 2023, according to the United States Federal Reserve. Historically, Resident Population in Jefferson County, OH reached a record high of 97.10000 in January of 1971 and a record low of 64.02600 in January of 2023. Trading Economics provides the current actual value, an historical data chart and related indicators for Resident Population in Jefferson County, OH - last updated from the United States Federal Reserve on May of 2024.