Piney Flats is an unincorporated community in Sullivan County in the U.S. state of Tennessee. It is part of the Kingsport–Bristol (TN)–Bristol (VA) Metropolitan Statistical Area, which is a component of the Johnson City–Kingsport–Bristol, TN-VA Combined Statistical Area – commonly known as the "Tri-Cities" region. Some areas of Piney Flats along U.S. Route 11E have been annexed by Johnson City (south of the Allison Road and Piney Flats Road intersection) and Bluff City north of the intersection and areas along Allison Road & Piney Flats Road.
Piney Flats is located at 36°25′10″N 82°18′14″W / 36.41944°N 82.30389°W.
Piney Flats has an elementary and middle school named "Mary Hughes School." The school operates under the Sullivan County Board of Education and educates students from kindergarten to eighth grade. Upon completion at Mary Hughes, students will enter high school at Sullivan East High School.