Jackson Township is a township in Northumberland County, Pennsylvania, United States. The population at the time of the 2010 Census was 875, which documented a decline in population from the figure of 928 that was tabulated in 2000.
According to the United States Census Bureau, the township has a total area of , of which is land and (10.27%) is water.
As of the census of 2000, there were 928 people, 348 households, and 261 families residing in the township.
The population density was . There were 373 housing units at an average density of .
The racial makeup of the township was 98.38% White, 0.11% African American, 0.11% Native American, 0.54% Asian, 0.11% from other races, and 0.75% from two or more races. Hispanic or Latino of any race were 0.54% of the population.
There were 348 households, out of which 32.8% had children under the age of eighteen living with them; 67.5% were married couples living together, 4.6% had a female householder with no husband present, and 25.0% were non-families. 22.7% of all households were made up of individuals, and 13.5% had someone living alone who was sixty-five years of age or older.
The average household size was 2.58 and the average family size was 3.06.
Within the township, the population was spread out, with 26.6% who were under the age of eighteen, 5.2% who were aged eighteen to twenty-four, 28.2% who were aged twenty-five to forty-four, 24.8% who were aged forty-five to sixty-four, and 15.2% who were sixty-five years of age or older. The median age was thirty-nine years.
For every one hundred females, there were 100.4 males. For every one hundred females who were aged eighteen or older, there were 96.3 males.
The median income for a household in the township was $36,528, and the median income for a family was $44,091. Males had a median income of $32,014 compared with that of $21,944 for females.
The per capita income for the township was $16,039.
Approximately 8.3% of families and 15.4% of the population were living below the poverty line, including 16.8% of those who were under the age of eighteen and 8.2% of those who were aged sixty-five or older.