Resident Population in Worcester County, MA was 888.50200 Thous. of Persons in January of 2025, according to the United States Federal Reserve. Historically, Resident Population in Worcester County, MA reached a record high of 888.50200 in January of 2025 and a record low of 637.03700 in January of 1970. Trading Economics provides the current actual value, an historical data chart and related indicators for Resident Population in Worcester County, MA - last updated from the United States Federal Reserve on May of 2026.