S.D. Codified Laws § 21-51-1
An action upon a contract or bond for the purchase or sale of real property, or for the recovery of the consideration payable thereunder must be commenced within fifteen years after the cause of action shall have accrued, or within fifteen years after the last payment thereunder shall have become due and payable, and, if not so commenced, such action shall be forever barred, and such contract or bond shall become null and void and if there be no conveyance of record from the vendor or his successor in interest to the purchaser or his successor in interest, such contract or bond shall be conclusively presumed to have been terminated, and such contract or bond shall cease to be notice of any rights of the purchaser and said period of fifteen years shall not be extended by nonresidence, legal disability or partial payment. This section shall apply to all such contracts or bonds affecting real estate in this state, both those heretofore executed and those hereafter executed.
SDCL 21-51-1