The population count of Essex County, MA was 757,395 in 2014. The population count of Plymouth County, MA was 500,772 in 2014. The population count of Hillsborough County, NH was 402,776 in 2014. The population count of Rockingham County, NH was 297,702 in 2014.
Population
Population Change
Above charts are based on data from the U.S. Census American Community Survey | ODN Dataset | API -