The listed states below are reciprocal with South Carolina. Out of state residents from these states may care a concealed firearm in South Carolina. All out of state residents must abide by the restrictions set in South Carolina law regarding concealed firearms.
Alaska - Arizona - Arkansas - Florida - Georgia - Idaho (Enhanced Only) - Kansas - Kentucky - Louisiana - Michigan - Mississippi (Enhanced Only) - Missouri - New Mexico - North Carolina- North Dakota (Enhanced Only) - Ohio - Oklahoma - South Dakota (Enhanced Only) - Texas - Tennessee - Virginia - West Virginia (21 years or older) - Wyoming
For reference see the Reciprocity page on SLED's website
http://www.sled.sc.gov/Reciprocity1.aspx?MenuID=CWP