(a) The total tax imposed by this chapter is due and payable not later than March 1 after the end of the calendar year for which the tax is due.
(b) A captive insurance company that had a net tax liability for the previous calendar year of more than $1,000 shall make semiannual prepayments of tax on March 1 and August 1. The tax paid on each date must be equal to 50 percent of the total amount of tax the company paid under this chapter for the previous calendar year. If the company did not pay a tax under this chapter during the previous calendar year, the tax paid on each date must be equal to the tax that would be owed on the aggregate of the gross premiums for the two previous calendar quarters.
(c) The comptroller may refund any overpayment of taxes that results from the semiannual prepayment system prescribed by this section.