South Hill is a census-designated place in Pierce County, Washington, immediately south of Puyallup. The population was 64,708 at time of the 2020 census, up from 52,431 in 2010. The area primarily consists of suburban housing and shopping with several retail shopping centers, residential neighborhoods, and apartment/condo complexes through…South Hill is a census-designated place in Pierce County, Washington, immediately south of Puyallup. The population was 64,708 at time of the 2020 census, up from 52,431 in 2010. The area primarily consists of suburban housing and shopping with several retail shopping centers, residential neighborhoods, and apartment/condo complexes throughout. Because South Hill is unincorporated, its addresses are part of the Puyallup "postal city" or ZCTA.