Resident Population in Washington County, RI was 129.98200 Thous. of Persons in January of 2023, according to the United States Federal Reserve. Historically, Resident Population in Washington County, RI reached a record high of 130.88000 in January of 2021 and a record low of 83.80000 in January of 1975. Trading Economics provides the current actual value, an historical data chart and related indicators for Resident Population in Washington County, RI - last updated from the United States Federal Reserve on May of 2024.