Shillington is a small suburban area nestled amongst other suburbs outside of Reading. More than 2000 students attend the Governor Mifflin High School, Middle School, and Cumru Elementary School (all part of the Governor Mifflin School District) located in Shillington. Governor Mifflin School District serves the borough and is its largest employer. Governor Mifflin Senior High School was formerly known as Shillington High School until 1953.
As of the census of 2000, there were 5,059 people, 2,238 households, and 1,405 families residing in the borough. The population density was 4,964.4 people per square mile (1,915.0/km²). There were 2,321 housing units at an average density of 2,277.6/sq mi (878.6/km²). The racial makeup of the borough was 97.11% White, 0.49% African American, 0.10% Native American, 0.53% Asian, 0.75% from other races, and 1.01% from two or more races. Hispanic or Latino of any race were 2.10% of the population.
There were 2,238 households out of which 26.5% had children under the age of 18 living with them, 50.0% were married couples living together, 9.6% had a female householder with no husband present, and 37.2% were non-families. 31.7% of all households were made up of individuals and 14.4% had someone living alone who was 65 years of age or older. The average household size was 2.26 and the average family size was 2.84.
In the borough the population was spread out with 21.5% under the age of 18, 6.6% from 18 to 24, 29.3% from 25 to 44, 21.1% from 45 to 64, and 21.5% who were 65 years of age or older. The median age was 40 years. For every 100 females there were 89.8 males. For every 100 females age 18 and over, there were 84.4 males.
The median income for a household in the borough was $43,833, and the median income for a family was $52,500. Males had a median income of $35,318 versus $27,179 for females. The per capita income for the borough was $22,322. About 2.2% of families and 3.7% of the population were below the poverty line, including 2.4% of those under age 18 and 5.3% of those age 65 or over.