S.C. Code Ann. § 63-1-45

For purposes of developing an accurate statewide count of homeless children and youth in this State, the following statewide definitions shall be used: (1) "Unaccompanied homeless youth" means an unaccompanied individual twenty-four years of age or younger who is not in the physical custody of a parent or guardian and lacks a fixed, regular, and adequate nighttime residence and includes: (a) children and youth who are sharing the housing of other persons due to loss of housing, economic hardship, or a similar reason; are living in motels, hotels, or camping grounds due to the lack of alternative adequate accommodations; are living in emergency or transitional shelters; or are abandoned in hospitals; (b) children and youth who have a primary nighttime residence that is a public or private place not designed for or ordinarily used as a regular sleeping accommodation for human beings, such as a car, a park, public spaces, an abandoned building, a bus or train station, or similar settings; or (c) children and youth who live in a supervised publicly or privately owned shelter designated to provide temporary living arrangements or in a transitional housing program or other time-limited housing. "Unaccompanied homeless youth" does not include any individual imprisoned or otherwise detained pursuant to a federal or state law except when a youth is exiting an institution having resided there for ninety days or fewer and meets the criteria in subitems (a), (b), or (c) immediately prior to entering the institution. (2) "Homeless child or youth" means children and youth from birth through twenty-four years of age who lack a fixed, regular, and adequate nighttime residence and includes: (a) children and youth who are sharing the housing of other persons due to loss of housing, economic hardship, or a similar reason; are living in motels, hotels, or camping grounds due to the lack of alternative adequate accommodations; are living in emergency or transitional shelters; or are abandoned in hospitals; (b) children and youth who have a primary nighttime residence that is a public or private place not designed for or ordinarily used as a regular sleeping accommodation for human beings, such as a car, a park, public spaces, an abandoned building, a bus or train station, or similar settings; (c) children and youth who live in a supervised publicly or privately owned shelter designated to provide temporary living arrangements or in a transitional housing program or other time-limited housing; or (d) migratory children as defined in 20 U.S.C. Section 6399, who are legally in the United States, and who qualify as homeless because they are living in circumstances described in subsections (a) through (c). "Homeless youth" does not include any individual imprisoned or otherwise detained pursuant to a federal or state law except when a youth is exiting an institution having resided there for ninety days or less and met the criteria in subitems (a), (b), or (c) immediately prior to entering the institution. (3) "Youth at risk of homelessness" means an individual twenty-four years of age or younger whose status or circumstances indicate a significant danger of experiencing homelessness in the near future and includes: (a) children and youth exiting a publicly funded institution or system of care; (b) children and youth who have previously experienced homelessness; (c) children and youth whose primary caregivers are currently homeless or have previously been homeless; or (d) children and youth who experience serious or sustained conflict with the individual's caregivers that is likely to result in family separation.