Deadline to register in the 2016 Elections in October 24. https://sdsos.gov/elections-voting/voting/register-to-vote/.
Title 12 of South Dakota Codified Laws covers state and local elections:
12-1-1. Elections to which title applies. The provisions of this title shall apply to all elections for state, district, and county officers and other officers except in cases where from the context of any statute a different intention plainly appears.
Source: PolC 1877, ch 27, § 1; CL 1887, § 1440; RPolC 1903, § 1863; RC 1919, § 7210; SDC 1939, § 16.0101.
The South Dakota Secretary of State Voter Information Portal is provided as a public service by the Secretary of State in cooperation with the County Auditors in each of South Dakota’s 66 counties. Individuals may search for their personal voter registration information, polling place location and your sample ballot for elections utilizing this system. Absentee voters can track information regarding the date the absentee ballot application the date the absentee ballot was sent to the voter and the date the absentee ballot was received.