S.D. Codified Laws § 12-27-28
If any political committee required to file a campaign finance disclosure report pursuant to this chapter receives a contribution of five hundred dollars or more within the twenty days immediately prior to an election for which a campaign finance disclosure report may be filed, a supplemental report shall be filed. The report shall state the name and mailing address of the contributor and the amount and date of the contribution, and information contained in any report provided under § 12-27-19, if applicable. The report shall be filed by the treasurer within forty-eight hours of the receipt of the contribution. A violation of this section is a Class 2 misdemeanor. A subsequent offense within a calendar year is a Class 1 misdemeanor.
SDCL 12-27-28