Resident Population in Montgomery County, IN was 38.63300 Thous. of Persons in January of 2024, according to the United States Federal Reserve. Historically, Resident Population in Montgomery County, IN reached a record high of 38.63300 in January of 2024 and a record low of 33.93000 in January of 1970. Trading Economics provides the current actual value, an historical data chart and related indicators for Resident Population in Montgomery County, IN - last updated from the United States Federal Reserve on April of 2026.