New Liberty is a city in Scott County, Iowa, United States. The population was 138 at the time of the 2020 census. New Liberty is located at 41°…New Liberty is a city in Scott County, Iowa, United States. The population was 138 at the time of the 2020 census. New Liberty is located at 41°43′2″N 90°52′46″W / 41.71722°N 90.87944°W. According to the United States Census Bureau, the city has a total area of 0.10 square miles, all land.