(1) All taxpayers shall compute the amount of tax payable under this chapter and shall remit the amount to the department of revenue on or before the 15th day of the 5th month following the close of the tax period.
(2) (a) A corporation shall make estimated tax payments if its annual estimated tax is $5,000 or more. Subject to the due date provision in 15-31-111 (2)(b), the estimated payments must be made in installments, as follows, if the $5,000 threshold is met or exceeded:
(i) For a corporation taxed on a calendar-year basis: For the following required installments the due date is: