The tax imposed by this chapter shall be payable as follows:

1. (1) Calendar year corporations. — Twenty-five percent of the estimated tax liability for the current taxable year shall each be paid with the tentative return required to be filed on or before April 1 of the current taxable year, June 15 of the current taxable year, September 15 of the current taxable year and January 15 of the immediately following taxable year.
2. (2) Fiscal year corporations. — Twenty-five percent of the estimated tax liability for the current taxable year shall each be paid with the tentative return required to be filed on or before the April 1 of the current taxable year, June 15 of the current taxable year, September 9 of the current taxable year and January 1 of the immediately following taxable year.
3. (3) Additional taxes due on final return. — Any additional tax due as computed in the final return required to be filed pursuant to § 6404 of this title shall be paid with such final return.
4. (4) Tentative tax declarations and payments are not required for returns for taxable periods of less than 92 calendar days.

74 Del. Laws, c. 256, § 1