S.D. Codified Laws § 12-6-26
Current with legislation signed by the governor on or before 3/6/2024
No person may vote a party ballot at any primary election unless the person is registered as a member of that political party in the precinct in which the person seeks to vote. Any political party in its constitution or bylaws may allow for participation in the party's primary elections by any person who is registered to vote with no party affiliation. Any such change to the constitution or bylaws of a political party shall be filed pursuant to § 12-5-1.1 by January first of the year in the which the primary is conducted.
SDCL 12-6-26