Lancaster Township, Butler County, Pennsylvania  Lancaster Township is a township in Butler County, Pennsylvania, in the United States. As of the 2010 census, the township population was 2,532. Lancaster Township is located along the western border of Butler County, with Beaver and Lawrence counties to the west. The township includes the unincorporated community of Middle Lancaster. Interstate 79 passes through the township with no exits. The nearest access points from I-79 are Exit 88 to the south in Jackson Township and Exit 96 to the north in Muddy Creek Township. U.S. Route 19, the Perry Highway, is a parallel local road that passes through the center of Middle Lancaster. According to the United States Census Bureau, the township has a total area of , of which , or 0.03%, is water. At the 2000 census there were 2,511 people in 906 households, including 755 families, in the township. The population density was 107.4 people per square mile (41.5/km²). There were 932 housing units at an average density of 39.9/sq mi (15.4/km²). The racial makeup of the township was 99.00% White, 0.24% African American, 0.24% Asian, 0.04% Pacific Islander, 0.08% from other races, and 0.40% from two or more races. Hispanic or Latino of any race were 0.44%. There were 906 households, 36.4% had children under the age of 18 living with them, 73.0% were married couples living together, 6.1% had a female householder with no husband present, and 16.6% were non-families. 13.8% of households were made up of individuals, and 3.2% were one person aged 65 or older. The average household size was 2.77 and the average family size was 3.04. The age distribution was 25.9% under the age of 18, 6.2% from 18 to 24, 31.0% from 25 to 44, 27.4% from 45 to 64, and 9.6% 65 or older. The median age was 39 years. For every 100 females, there were 107.0 males. For every 100 females age 18 and over, there were 101.3 males. The median household income was $49,524 and the median family income was $53,621. Males had a median income of $39,286 versus $25,962 for females.