S.D. Codified Laws § 25-3-4
A marriage may be annulled by an action in the circuit court to obtain a decree of nullity if the party in whose behalf it is sought to have the marriage annulled was under the age of legal consent at the time of the marriage, and such marriage was contracted without the consent of his or her parents or guardian or person having charge of him or her, unless, after attaining the age of consent, such party for any time freely cohabitated with the other as husband or wife. An action to obtain a decree of nullity of marriage for causes mentioned in this section must be commenced by the party to the marriage who was married under the age of legal consent, within four years after arriving at the age of consent, or by a parent, guardian, or other person having charge of such nonaged male or female, at any time before such married minor has arrived at the age of legal consent.
SDCL 25-3-4