Lake Wylie is a census-designated place (CDP) in York County, South Carolina, United States. The population was 8,841 at the 2010 census. Lake Wylie is located on a peninsula along the shore of Lake Wylie, a reservoir that was named for Dr. W. Gil Wylie in 1960. It is a suburb of Charlotte, North Carolina.
Lake Wylie is located on a peninsula along the shore of Lake Wylie in the Piedmont of both North and South Carolina, at 35°6′22″N 81°3′25″W (35.105973, -81.056978). According to the United States Census Bureau, the CDP has a total area of 4.7 square miles (12 km2), of which 3.5 square miles (9.1 km2) is land and 1.3 square miles (3.4 km2) (26.58%) is water. The average elevation of the town was 512 feet.
As a result of the community's proximity to the state line between North and South Carolina, it has been significantly affected by recent efforts to resurvey the state line using modern global positioning system technology. The process shifted the state line approximately 150 feet (46 m) southward in the Lake Wylie area, resulting in several properties in the community now being located in South Point Township in North Carolina — including one property where the new state line falls between the owner's house and his back deck, and a gas station and convenience store whose owner has noted that differences in gas prices and retail regulations between the two states will likely force him out of business.
Lake Wylie has a humid subtropical climate, characterized by humid summers and cool dry winters.