The Town of Decatur is a town located on the eastern border of Otsego County, New York, United States. As of the 2010 U.S. census, it had a population of 353. It is named for naval hero Stephen Decatur.
According to the United States Census Bureau, the town has a total area of 20.8 square miles (54 km), of which, 20.6 square miles (53 km) of it is land and 0.2 square miles (0.52 km) of it (0.87%) is water.
The east town line is the border of Schoharie County.
As of the census of 2000, there were 410 people, 158 households, and 117 families residing in the town. The population density was 19.9 people per square mile (7.7/km²). There were 281 housing units at an average density of 13.6 per square mile (5.3/km²). The racial makeup of the town was 98.78% White, 0.24% African American, 0.24% Asian, 0.49% from other races, and 0.24% from two or more races. Hispanic or Latino of any race were 1.46% of the population.
There were 158 households out of which 29.1% had children under the age of 18 living with them, 66.5% were married couples living together, 4.4% had a female householder with no husband present, and 25.9% were non-families. 19.6% of all households were made up of individuals and 10.1% had someone living alone who was 65 years of age or older. The average household size was 2.59 and the average family size was 2.99.
In the town, the population was spread out with 23.9% under the age of 18, 6.1% from 18 to 24, 23.7% from 25 to 44, 29.0% from 45 to 64, and 17.3% who were 65 years of age or older. The median age was 42 years. For every 100 females, there were 115.8 males. For every 100 females age 18 and over, there were 105.3 males.
The median income for a household in the town was $29,896, and the median income for a family was $38,125. Males had a median income of $29,219 versus $21,458 for females. The per capita income for the town was $16,541. About 2.6% of families and 4.4% of the population were below the poverty line, including 7.8% of those under age 18 and none of those age 65 or over.