Resident Population in Mason County, MI was 29.15900 Thous. of Persons in January of 2023, according to the United States Federal Reserve. Historically, Resident Population in Mason County, MI reached a record high of 29.40900 in January of 2022 and a record low of 22.61200 in January of 1970. Trading Economics provides the current actual value, an historical data chart and related indicators for Resident Population in Mason County, MI - last updated from the United States Federal Reserve on May of 2024.