Seabrook Island is a town in Charleston County, South Carolina, United States. The population was 1,250 at the 2000 census. As defined by the U.S. Office of Management and Budget, and used by the U.S. Census Bureau for statistical purposes only, Seabrook Island is included within the Charleston-North Charleston-Summerville metropolitan area.

In 1666, British subject Lt. Col. Robert Sanford arrived on Seabrook as an explorer in royal service to King Charles II. By 1684, the local Stono Indians were persuaded to cede their lands to the proprietary government, which in turn sold the property to English settlers.

During the American Revolutionary years, the island was used as a staging area for Hessian and British troops. In 1816, the island was sold to William Seabrook of nearby Edisto Island, hence the present name. Under Seabrook’s ownership, the island was used for growing cotton. At the height of the Civil War, Seabrook sold the island to William Gregg who rented the land to Charles Andell.

After the turn of the century, the island was sold to sportsmen for hunting, fishing, and recreation. In 1939, the Episcopal Diocese of South Carolina rented land on Seabrook to establish a summer camp for underprivileged children. In 1951, about 1,408 acres of land were given to the church.

In 1970, the diocese sold about 1,100 acres to private developers who planned the private, residential community that Seabrook Island is today. Eighteen years later, the town of Seabrook was incorporated, and it celebrated a decade of private ownership and self-government in 1997.