Chatham /ˈtʃætəm/ is a town in Columbia County, New York, United States. The population was 4,128 at the 2010 census.
According to the United States Census Bureau, the town has a total area of 53.6 square miles (138.7 km), of which 53.2 square miles (137.9 km) is land and 0.31 square miles (0.8 km), or 0.59%, is water.
The north town line is the border of Rensselaer County.
The north end of the Taconic State Parkway is in the town, and Interstate 90 passes through the town.
New York State Route 66 and New York State Route 203 intersect in the town.
As of the census of 2000, there were 4,249 people, 1,762 households, and 1,196 families residing in the town. The population density was 79.8 people per square mile (30.8/km²). There were 2,110 housing units at an average density of 39.6 per square mile (15.3/km²). The racial makeup of the town was 96.00% White, 1.74% Black or African American, 0.21% Native American, 0.71% Asian, 0.16% Pacific Islander, 0.16% from other races, and 1.01% from two or more races. Hispanic or Latino of any race were 0.75% of the population.
There were 1,762 households out of which 29.4% had children under the age of 18 living with them, 56.1% were married couples living together, 8.3% had a female householder with no husband present, and 32.1% were non-families. 25.1% of all households were made up of individuals and 8.3% had someone living alone who was 65 years of age or older. The average household size was 2.41 and the average family size was 2.87.
In the town, the population was spread out with 23.5% under the age of 18, 5.7% from 18 to 24, 24.6% from 25 to 44, 33.0% from 45 to 64, and 13.2% who were 65 years of age or older. The median age was 43 years. For every 100 females, there were 96.0 males. For every 100 females age 18 and over, there were 93.1 males.
The median income for a household in the town was $49,234, and the median income for a family was $60,097. Males had a median income of $40,067 versus $26,452 for females. The per capita income for the town was $28,599. About 4.8% of families and 6.6% of the population were below the poverty line, including 6.6% of those under age 18 and 4.6% of those age 65 or over.
Chatham New York neighborhoods include: Chatham, Pond Hill/Kinderhook, Spencertown, Red Rock