Lewis Township is a township that is located in Northumberland County, Pennsylvania, United States. The population at the time of the 2010 Census was 1,915,[3] an increase over the figure of 1,862 that was tabulated in 2000.
There were 636 households, out of which 36.5% had children under the age of eighteen living with them; 79.1% were married couples living together, 3.6% had a female householder with no husband present, and 13.4% were non-families. 11.6% of all households were made up of individuals, and 6.0% had someone living alone who was sixty-five years of age or older.
The average household size was 2.89, and the average family size was 3.11.
Within the township, the population was spread out, with 25.7% of residents who were under the age of eighteen, 7.9% who were aged eighteen to twenty-four, 26.0% who were aged twenty-five to forty-four, 28.3% who were aged forty-five to sixty-four, and 12.0% who were sixty-five years of age or older. The median age was thirty-nine years.
For every one hundred females, there were 103.9 males. For every one hundred females who were aged eighteen or older, there were 101.0 males.
The median income for a household in the township was $41,406, and the median income for a family was $44,922. Males had a median income of $32,101 compared with that of $21,767 for females.
Approximately 3.9% of families and 7.6% of the population were living below the poverty line, including 14.4% of those who were under the age of eighteen and 5.6% of those who were aged sixty-five or older.