Joint estimated tax of husband and wife.

(1) General. A husband and wife may make the required annual payment determined under subparagraph (ii) of paragraph (4) of subdivision (a) of this section as if they were one taxpayer. If joint installments of estimated tax are made by such husband and wife, the liability determined under paragraph (1) of subdivision (a) of this section is joint and several. While joint installments may be made by a husband and wife, even though they are not living together, no such installments may be made if such husband and wife are separated under a decree of divorce or separate maintenance, or if they have different taxable years. If joint installments are made, the tax, as defined in subdivision (b) of this section, must be estimated as if a joint New York State personal income tax return will be filed for the taxable year.

(2) Application to separate New York State personal income tax returns. The fact that joint installments of estimated tax are made by a husband and wife will not preclude them from filing separate New York State personal income tax returns. Where joint installments of estimated tax are made but joint New York State personal income tax returns are not filed for the same taxable year, the estimated tax installments for such year may be treated as installments on account of the tax (as defined in subdivision (b) of this section) liability of either the husband or wife for the taxable year or may be divided between them in such manner as they may agree. In the event the husband and wife fail to agree to a division, the portion of such installments allocated to a spouse will be that portion of the aggregate of all such installments of estimated tax made, as the amount of tax (as defined in subdivision (b) of this section) shown on the separate New York State personal income tax return of the taxpayer bears to the sum of the taxes (as defined in subdivision (b) of this section) shown on the separate New York State personal income tax returns of the taxpayer and such taxpayer's spouse.

(3) Death of a spouse.

(i) If joint installments of estimated tax are made by a husband and wife and thereafter one spouse dies, no further installments of estimated tax are required from the estate of the decedent. (An estate is not required, in order to avoid the addition to tax referred to in subdivision (a) of this section, to make estimated tax payments for the first two taxable years after the date of the death of the decedent. See subdivision (h) of this section.) The surviving spouse, however, may either continue to make joint installments of estimated tax or such spouse may make separate installments of estimated tax. If a surviving spouse elects to make separate installments of estimated tax and in the event a joint New York State personal income tax return is not filed, the joint installments previously made, may be divided between the decedent and the surviving spouse in such proportion as the surviving spouse and the legal representative of the decedent may agree.

(ii) In the absence of such agreement, if separate New York State personal income tax returns are filed by or on behalf of both the decedent and surviving spouse, the joint installments of estimated tax made up to the date of death will be allocated to each New York State personal income tax return in the proportion that the amount of the tax (as defined in subdivision (b) of this section) shown on the separate New York State personal income tax return bears to the tax (as defined in subdivision (b) of this section) shown the on such separate New York State personal income tax returns of the surviving spouse and of the decedent. If such separate New York State personal income tax returns are filed by or on behalf of each spouse and both New York State personal income tax returns disclose no tax (as defined in subdivision (b) of this section) liability or if a separate New York State personal income tax return is not filed by or on behalf of either spouse, the aggregate amount of such installments will be equally divided.