Hamer is an unincorporated community and census-designated place in Dillon County, South Carolina, United States. It was first listed as a CDP in the 2020 census with a population of 820.Hamer is home to Hamer Hall, a residence from 1890 listed on the National Register of Historic Places. It is also the location of South of the Border, a famed tourist trap just before the state line with North Carolina; and it is the home of Blenheim Ginger Ale.