Resident Population in Smith County, TN was 20.53800 Thous. of Persons in January of 2023, according to the United States Federal Reserve. Historically, Resident Population in Smith County, TN reached a record high of 20.53800 in January of 2023 and a record low of 12.50900 in January of 1970. Trading Economics provides the current actual value, an historical data chart and related indicators for Resident Population in Smith County, TN - last updated from the United States Federal Reserve on May of 2024.