Hartly is a town in Kent County, Delaware, United States. It is part of the Dover, Delaware Metropolitan Statistical Area. The population was 74 at the 2010 census, making it the least populous municipality in Delaware.
Hartly is located at 39°10′07″N 75°42′48″W.
According to the United States Census Bureau, the town has a total area of 0.1 square miles (0.26 km2), all of it land.
Hartly is located at the intersection of Delaware Route 11 and Delaware Route 44. The town is home to about 31 residences, the Hartly Volunteer Fire Company, a post office, Hartly Elementary School, 2 daycares, Hartly Feed and Hardware, and a Family Dollar store. There are several vacant and abandoned buildings along with empty lots in Hartly.
At the 2000 census there were 78 people in 25 households, including 21 families, in the town. The population density was 1,345.9 people per square mile (501.9/km²). There were 31 housing units at an average density of 534.9 per square mile (199.5/km²). The racial makeup of the town was 91.03% White, 3.85% African American, 1.28% from other races, and 3.85% from two or more races. Hispanic or Latino of any race were 2.56%.
Of the 25 households 60.0% had children under the age of 18 living with them, 52.0% were married couples living together, 24.0% had a female householder with no husband present, and 16.0% were non-families.