Wellsville is a borough in York County, Pennsylvania, United States. The population was 242 at the 2010 census.
Wellsville changed very little visually during the twentieth century; the borough's appearance has remained that of a nineteenth-century community, complete with brick sidewalks and Gothic Revival and Greek Revival houses.
Because of its unusually high quality of preservation, nearly all of the community was placed on the National Register of Historic Places in 1977 as the "Wellsville Historic District". Among the district's 48 contributing properties are an 1850s Methodist church, a small group of nineteenth-century commercial buildings, and the Wellsville House, an 1870s structure that has been used as a factory, museum, and restaurant.
Wellsville is located at 40°3′1″N 76°56′26″W (40.050335, -76.940533).
According to the United States Census Bureau, the borough has a total area of 0.1 square miles (0.26 km2), all of it land.
As of the census of 2000, there were 279 people, 118 households, and 78 families residing in the borough. The population density was 2,004.1 people per square mile (769.4/km²). There were 124 housing units at an average density of 890.7 per square mile (342.0/km²). The racial makeup of the borough was 97.13% White, 1.43% African American, 1.08% Asian, and 0.36% from two or more races.
There were 118 households out of which 34.7% had children under the age of 18 living with them, 52.5% were married couples living together, 8.5% had a female householder with no husband present, and 33.1% were non-families. 27.1% of all households were made up of individuals and 11.0% had someone living alone who was 65 years of age or older. The average household size was 2.36 and the average family size was 2.85.