S.D. Codified Laws § 2-14-14
Current with legislation signed by the governor on or before 3/6/2024
The time in which any act provided by law is to be done is computed by excluding the first day and including the last, unless the last is a holiday and then it also is excluded.
Fractions of a day are to be disregarded in computations which include more than one day, and involve no questions of priority.
SDCL 2-14-14