Upper St. Clair is a township with home rule status in southern Allegheny County, Pennsylvania, United States, located approximately 8 miles (13 km) south of Downtown Pittsburgh.

Lebanon to the north, Bethel Park to the east, and Peters Township in Washington County to the south.

Under his administration as president from February 2, 1787, to October 29, 1787, the Northwest Ordinance and United States Constitution of 1787 were passed.

[3] The first European settler in present-day Upper St. Clair was John Fife, who settled near what is now the intersection of Washington and McLaughlin Run roads in 1762.

Freehold Real Estate Co. built the first major residential development in March 1913 along Washington Road, which at the time was conveniently close to streetcar service.

During the 1930s, Upper St. Clair was recorded as a community within the city which had a school district providing regular nursing services.

[8][9][10] According to the United States Census Bureau, the township has a total area of 9.8 square miles (25 km2), of which 0.10% is water.

In addition, a church named for St. Louise de Marillac hosts a private Catholic-affiliated school serving from Pre-K to 8th grade.