SDCL § 10-39-67: Filing verified estimates--Payment due.

Effective January 1, 1993, persons required to report net profits tax shall file verified estimates of the tax due and pay one-fourth of the tax on the last day of April for the quarter ending on March thirty-first, on the last day of July for the quarter ending June thirtieth, on the last day of October for the quarter ending September thirtieth, and on the last day of January for the quarter ending December thirty-first. The final return and final payment of any additional tax due for the preceding calendar year is due June first of the year following the year for which the report is due.