S.D. Codified Laws § 10-13-39
Each owner-occupied single-family dwelling in this state is specifically classified for the purpose of taxation. For the purposes of this section, an owner-occupied single-family dwelling is a house, condominium apartment, residential housing consisting of four or less family units, town house, town home, housing cooperatives where membership in the cooperative is strictly limited to stockholder occupants of the building, dwelling as classified in § 10-13-39.1, and manufactured or mobile home as defined in § 32-3-1, which is assessed and taxed as a separate unit, including an attached or unattached garage and the parcel of land upon which the structure is situated as recorded in the records of the director of equalization. A person may only have one dwelling, which is the person's principal place of residence as defined in § 12-1-4, classified as an owner-occupied single-family dwelling. If the owner occupies fifty percent or more of the living space within the dwelling, the entire dwelling is classified as an owner-occupied single- family dwelling. If the owner occupies a duplex, triplex, or fourplex, or less than fifty percent of the living space within the dwelling, the portion of the dwelling so occupied shall be classified as an owner-occupied single-family dwelling.
SDCL 10-13-39