Rensselaerville is a town in Albany County, New York, United States. The population was 1,843 at the 2010 census. The town is named after Stephen Van Rensselaer.
According to the United States Census Bureau, the town has a total area of 61.9 square miles (160 km), of which 61.5 square miles (159 km) is land and 0.4 square miles (1.0 km) (0.63%) is water.
The south town line is the border of Greene County, and the west town line is the border of Schoharie County. The town is located in the northern Catskill Mountains.
Catskill Creek and its tributaries, Lake Creek, Fox Creek, Tenmile Creek, Greene Kill and Eightmile Creek, flow through the town.
At the 2000 census, there were 1,915 people, 779 households and 527 families residing in the town. The population density was 31.2 per square mile (12.0/km²). There were 1,187 housing units at an average density of 19.3 per square mile (7.5/km²). The racial makeup of the town was 95.98% White, 1.98% African American, 0.05% Native American, 0.16% Asian, 0.78% from other races, and 1.04% from two or more races. Hispanic or Latino of any race were 1.20% of the population.
There were 779 households of which 29.0% had children under the age of 18 living with them, 55.5% were married couples living together, 7.6% had a female householder with no husband present, and 32.3% were non-families. 25.2% of all households were made up of individuals and 10.7% had someone living alone who was 65 years of age or older. The average household size was 2.43 and the average family size was 2.93.
24.4% of the population were under the age of 18, 5.8% from 18 to 24, 24.0% from 25 to 44, 30.5% from 45 to 64, and 15.2% who were 65 years of age or older. The median age was 42 years. For every 100 females, there were 103.3 males. For every 100 females age 18 and over, there were 99.0 males.
The median household income was $42,391, and the median income for a family was $51,607. Males had a median income of $34,563 and females $30,298. The per capita income was $20,921. About 2.8% of families and 5.3% of the population were below the poverty line, including 6.2% of those under age 18 and 3.4% of those age 65 or over.