Onondaga is a town located in Onondaga County, New York, United States. As of the 2010 U.S. Census, the town had a population of 23,103. The town is named after the native Onondaga tribe, part of the Iroquois Confederacy. Onondaga is located southwest of the city of Syracuse, which it borders.
According to the United States Census Bureau, the town has a total area of 57.8 square miles (150 km), of which, 57.7 square miles (149 km) of it is land and 0.1 square miles (0.26 km) of it (0.16%) is water.
Interstate 81 passes along the east side of the town. U.S. Route 11 is a north-south highway in the eastern part of Onondaga, paralleling the interstate. U.S. Route 20 is an east-west highway in the south of the town. New York State Route 173 is an east-west highway through the middle of Onondaga. New York State Route 11A diverges westward from US-11. New York State Route 80 cuts through the south part of the town.
As of the census of 2000, there were 21,063 people, 7,679 households, and 5,513 families residing in the town. The population density was 364.9 people per square mile (140.9/km²). There were 7,964 housing units at an average density of 138.0 per square mile (53.3/km²). The racial makeup of the town was 94.29% White, 1.96% African American, 1.07% Native American, 1.16% Asian, 0.04% Pacific Islander, 0.16% from other races, and 1.32% from two or more races. Hispanic or Latino of any race were 1.05% of the population.
There were 7,679 households out of which 35.1% had children under the age of 18 living with them, 60.4% were married couples living together, 8.1% had a female householder with no husband present, and 28.2% were non-families. 23.5% of all households were made up of individuals and 11.2% had someone living alone who was 65 years of age or older. The average household size was 2.64 and the average family size was 3.15.
In the town, the population was spread out with 26.5% under the age of 18, 5.4% from 18 to 24, 27.2% from 25 to 44, 23.7% from 45 to 64, and 17.2% who were 65 years of age or older. The median age was 40 years. For every 100 females, there were 92.0 males. For every 100 females age 18 and over, there were 86.7 males.
The median income for a household in the town was $53,421, and the median income for a family was $63,674. Males had a median income of $42,495 versus $31,160 for females. The per capita income for the town was $25,522. About 2.6% of families and 4.2% of the population were below the poverty line, including 3.8% of those under age 18 and 6.7% of those age 65 or over.