SDCL § 10-62-7 — Books and records--Inspection--Retention period

Each person subject to tax under this chapter shall keep records and books of all receipts, together with invoices, and other pertinent papers and documents. The books and records and other papers and documents are, at all times during business hours of the day, subject to inspection by the secretary of revenue or the secretary's agents and employees to determine the amount of tax due. The books and records shall be preserved for a period of three years unless the secretary of revenue, in writing, authorized their destruction or disposal at an earlier date.