Hanover Township is a township in Morris County, in the U.S. state of New Jersey. As of the 2020 United States census, the township's population was 14,677, its highest decennial count ever and an increase of 965 from the 13,712 recorded at the 2010 census, which in turn reflected an increase of 814 from the 12,898 counted in the 2000 census. The to…Hanover Township is a township in Morris County, in the U.S. state of New Jersey. As of the 2020 United States census, the township's population was 14,677, its highest decennial count ever and an increase of 965 from the 13,712 recorded at the 2010 census, which in turn reflected an increase of 814 from the 12,898 counted in the 2000 census. The township comprises the unincorporated communities of Whippany and Cedar Knolls.