S.D. Codified Laws § 54-11-9
Current with legislation signed by the governor on or before 3/6/2024
The use of an accepted credit card or the issuance of a credit card agreement and the expiration of thirty days from the date of issuance without written notice from a card holder to cancel the account creates a binding contract between the card holder and the card issuer with reference to any accepted credit card, and any charges made with the authorization of the primary card holder.
SDCL 54-11-9