Jonesport is a town in Washington County, Maine, United States. The population was 1,245 at the 2020 census. Jonesport is a fishing and lobstering town. It contains the villages or hamlets of Jonesport, …Jonesport is a town in Washington County, Maine, United States. The population was 1,245 at the 2020 census. Jonesport is a fishing and lobstering town. It contains the villages or hamlets of Jonesport, Mason Bay, Monsapec, and West Jonesport.