8 Del. C. § 504

(a) The franchise tax shall be due and payable on March 1 following the close of the calendar year, except that with respect to a corporation whose franchise tax liability for the current calendar year is estimated to be $5,000 or more, a tentative return and tax shall be due and payable as follows:

(1) Forty percent of the estimated tax on June 1 of the current year;

(2) Twenty percent of the estimated tax on September 1 of the current year;

(3) Twenty percent of the estimated tax on December 1 of the current year; and

(4) The remainder of the tax as finally determined together with the annual franchise tax report on March 1 following the close of the calendar year.

(b) The Department of State shall receive the franchise tax and pay over all taxes collected to the Department of Finance, except as provided in § 506 of this title.

(c) If the tax of any corporation remains unpaid after the due dates established by this section, the tax shall bear interest at the rate of 11/2 percent for each month or portion thereof until fully paid.

(d) The Secretary of State has power to inquire into the truth or falsity or accuracy of every report required to be filed to carry out this chapter. The Secretary of State may require the production of the books of any corporation referred to in this chapter and may swear or affirm and examine witnesses in relation thereto. Where the Secretary of State shall determine the amount of franchise tax which has been paid is less than the franchise tax due, the Secretary of State shall notify the taxpayer of the additional tax and any interest thereon which is due. Such additional tax and interest thereon shall be paid, or a petition for review thereof shall be filed, within 60 days after the notification to the taxpayer.

(e) The tentative return and tax paid thereon under subsection (a) of this section shall be based on the annual franchise tax of the preceding year.

(f) The penalties for nonpayment of the tentative franchise tax as set forth in subsection (a) of this section shall be the same as those applied for any nonpayment of franchise tax in this title.

(g) The Secretary of State may in the Secretary of State’s discretion charge a fee of $60 for each check received for payment of franchise taxes, penalties or interest thereon that is returned due to insufficient funds or as the result of a stop payment order to be recovered by adding the amount of that fee to the franchise tax, and such sum shall become a part of the franchise tax and shall be collected in the same manner and subject to the same penalties.