Gilsum is a town in Cheshire County, New Hampshire, United States. The population was 813 at the 2010 census. Home to the Bear’s Den Natural Area, Gilsum includes Gilsum Lower Village.
According to the United States Census Bureau, the town has a total area of 16.7 square miles (43 km), of which 16.7 sq mi (43 km) is land and 0.04 sq mi (0.10 km) is water, comprising 0.12% of the town. The highest point in Gilsum is an unnamed hill along the town’s eastern boundary, where the elevation reaches 1,657 feet (505 m) above sea level. Gilsum is drained by the Ashuelot River and lies fully within the Connecticut River watershed.
The town is served by New Hampshire Route 10.
As of the census of 2000, there were 777 people, 310 households, and 220 families residing in the town. The population density was 46.6 people per square mile (18.0/km²). There were 343 housing units at an average density of 20.6 per square mile (7.9/km²). The racial makeup of the town was 98.46% White, 0.39% Native American, 0.13% Asian, and 1.03% from two or more races. Hispanic or Latino of any race were 0.51% of the population.
There were 310 households out of which 26.5% had children under the age of 18 living with them, 58.7% were married couples living together, 8.7% had a female householder with no husband present, and 29.0% were non-families. 23.9% of all households were made up of individuals and 6.5% had someone living alone who was 65 years of age or older. The average household size was 2.48 and the average family size was 2.90.
In the town, the population was spread out with 22.3% under the age of 18, 5.0% from 18 to 24, 30.0% from 25 to 44, 31.9% from 45 to 64, and 10.8% who were 65 years of age or older. The median age was 41 years. For every 100 females, there were 98.2 males. For every 100 females age 18 and over, there were 104.1 males.
The median income for a household in the town was $43,359, and the median income for a family was $50,469. Males had a median income of $35,150 versus $24,205 for females. The per capita income for the town was $20,955. About 1.9% of families and 7.0% of the population were below the poverty line, including 1.3% of those under age 18 and 13.7% of those age 65 or over.