S.D. Codified Laws § 8-3-7
No person may vote at any township meeting unless the person is registered to vote in the township pursuant to chapter 12-4 and resides in that township. For the purposes of this section, a person resides in the township if the person actually lives in the township for at least thirty consecutive days each year, is a full-time postsecondary education student who resided in the township immediately prior to leaving for the postsecondary education, or is on active duty as a member of the armed forces whose home of record is within the township. A voter's qualification as a resident may be challenged in the manner provided in § 12-18-10. No election may be contested on the grounds that any nonresident was allowed to vote if the nonresident was not challenged in the manner provided in § 12-18-10.
SDCL 8-3-7