56.1.1. Installment Dates. - In the case of a declaration of estimated income tax for a calendar year, the initial payment date and the subsequent payment dates are set forth in the following table: Date Of Dates Of
Filing Installment
Declaration Payments
(1) On or before April 15th . . . In four (4) equal installments - one (1) at time of filing declaration (on or before April 15), one (1) on or before June 15, one (1) on or before September 15, and one (1) on or before January 15 of the succeeding taxable year.
(2) After April 15 and before June 16,
if not required to be filed on or before
April 15 . . . In three (3) equal installments - one (1) at time of filing declaration (on or before June 15), one (1) on or before September 15, and one (1) on or before January 15 of the succeeding taxable year.
(3) After June 15 and before September
16, if not required to be filed on or before June 15 or... In two (2) equal installments one (1) at time of filing declaration (on or before September 15), and the other succeeding on or before January 15 of the succeeding taxable year.
(4) After September 15, if not required to be filed on or before September 15... In full at time of filing declaration.
56.1.1.1. Filing After The Prescribed Time. - If a declaration is filed after the time prescribed in Section 55 of these regulations, or after the expiration of any extension of time, items (2), (3) and (4) of the table set forth under Subsection 56.1.1 shall not apply, and there shall be paid at the time of filing the declaration of estimated tax all installments of the estimated tax which would have been payable on or before such date of filing if the declaration had been filed on or before its due date, determined without regard to any extension of time. The remaining installments shall be paid at the time and in the amounts in which they would have been payable if the declaration had been filed when originally due. 56.1.1.1.a. Example. - A taxpayer who was required to file a declaration of estimated income tax on or before April 15, 1989, files his declaration for 1989 on September 15, 1989. Under this example, at the time of filing his declaration, this taxpayer was delinquent in the payment of two (2) installments of his estimated income tax for the taxable year of 1989 and therefore three-fourths (3/4) of the estimated tax shown on his declaration must be paid.