(a) Due date for payment of estimated tax.— The estimated tax shall be paid as follows:(1) The due date of the first installment of the estimated tax required under § 30260 of this title is the fifteenth (15th) day of the fourth (4th) month of the taxable year, except as provided in clause (2) of this subsection. In this case, the estimated tax shall be paid in four (4) equal installments. The second (2nd) installment shall be paid the fifteenth (15th) day of the sixth (6th) month of the taxable year. The third (3rd) installment shall be paid the fifteenth (15th) day of the ninth (9th) month of the taxable year. The fourth (4th) installment shall be paid the fifteenth (15th) day of the first (1st) month of the following taxable year. Provided, That the first year in which the special tax on gross income takes effect, such payments shall be made on the remaining installments.(2) Exceptions.— If the requirements of § 30260(a) of this title are satisfied for the first time:(A) After the last day of the third (3rd) month and before the first day of the sixth (6th) month of the taxable year, the due date of the first installment shall be the fifteenth (15th) day of the sixth (6th)

the last day of the third (3rd) month and before the first day of the sixth (6th) month of the taxable year, the due date of the first installment shall be the fifteenth (15th) day of the sixth (6th) month of the taxable year. In this case, the estimated tax shall be paid in three (3) equal installments. The second installment shall be paid the fifteenth (15th) day of the ninth (9th) month of the taxable year, and the third installment shall be paid the fifteenth (15th) day of the first (1st) month of the following taxable year; or(B) after the last day of the fifth (5th) month and before the first (1st) day of the ninth (9th) month of the taxable year, the due date of the first installment shall be the fifteenth (15th) day of the ninth (9th) month of the taxable year. In this case, the estimated tax shall be paid in two (2) equal installments. The second installment shall be paid the fifteenth (15th) day of the first (1st) month of the following taxable year, or(C) after the last day of the eighth (8th) month of the taxable year, the due date of the first and only payment shall be the fifteenth (15th) day of the first (1st) month of the following taxable year.(b) Changes in the

y of the eighth (8th) month of the taxable year, the due date of the first and only payment shall be the fifteenth (15th) day of the first (1st) month of the following taxable year.(b) Changes in the computation of the estimated tax.— If any change in the computation of the estimated tax should arise, the remaining installments, if any, shall be ratably increased or reduced, as the case may be, to show the increase or reduction, as the case may be, in the estimated tax due to such change in the estimate.(c) Installments paid in advance.— At the election of the individual, any installment of the estimated tax may be paid prior to the date prescribed for its payment.(d) Payment as part of tax for taxable year.— Payment of the estimated tax, or any installment thereof, shall be considered payment on account of the tax for the taxable year. Assessment in respect of the estimated tax shall be limited to the amount paid. History —Jan. 31, 2011, No. 1, § 1061.21, retroactive to Jan. 1, 2011; June 30, 2013, No. 40, § 25.