Green Hills is a borough in Washington County, Pennsylvania, United States.

The borough was formed in 1978 when a local businessman worked to secede from the dry township of South Franklin after voters there defeated a referendum that would allow alcohol sales at his country club.^[3] The population was twenty at the time of the 2020 census,^[4] making it the third least populous borough in the state; only S.N.P.J. and Centralia had fewer residents.^[5]

Pennsylvania law has since been changed to require at least five hundred residents in a newly formed borough.^[5]

Green Hills is located at 40°6′48″N 80°17′58″W / 40.11333°N 80.29944°W / 40.11333; -80.29944 (40.113382, -80.299368).^[6]

According to the United States Census Bureau, the borough has a total area of 0.9 square miles (2.3 km²), of which 0.9 square miles (2.3 km²) is land and 1.08% is water.

Green Hills is mostly bordered by South Franklin Township; its only other border is with Buffalo Township to the northwest.

As of the census^[8] of 2000, there were eighteen people, seven households, and four families residing in the borough. The population density was 19.5 people per square mile (7.5 people/km²).

There were eight housing units at an average density of 8.7 per square mile (3.4/km²). The racial makeup of the borough was 100.00% White.

There were seven households, out of which three had children under the age of eighteen living with them. Five were married couples living together, and two were non-families.

Two households were made up of individuals, and none had someone living alone who was sixty-five years of age or older. The average household size was 2.57 and the average family size was 3.20.

The median age in the borough was thirty-six years. Among the eighteen residents, there were six children — four girls and two boys — six men, and six women. Of the adults, two were between the ages of eighteen and twenty-four, four were aged twenty-five to forty-four, three were aged forty-five to sixty-four, and three were sixty-five years of age or older.

The median income for a household in the borough was $94,239, and the median income for a family was $116,250. Males had a median income of $24,583 compared with $0 for females. The per capita income for the borough was $124,279.

No individuals or families were documented as falling below the poverty line.

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  A house in the borough