S.D. Codified Laws § 21-48-6.1
Current with legislation signed by the governor on or before 3/6/2024
At least twenty-one days prior to the date set for sale, the foreclosing creditor shall serve a written copy of the notice of foreclosure sale on the mortgagor and any lien holder or encumbrancer whose interest in the property being foreclosed would be affected by the foreclosure.
SDCL 21-48-6.1