N.Y. Tax Law § 1516
(a) To the extent the tax imposed by this article shall not have been previously paid pursuant to section fifteen hundred fourteen,
(b) If the taxpayer, within the time prescribed by subdivision (c) of section fifteen hundred fifteen, shall have applied for an automatic extension of time to file its annual return and shall have paid to the commissioner of taxation and finance on or before the date such application is filed an amount properly estimated as provided by said subdivision, the only amount payable in addition to the tax shall be interest at the underpayment rate set by the commissioner pursuant to subsection (e) of section one thousand ninety-six or, if no rate is set, at the rate of six percent per annum upon the amount by which the tax, or portion thereof payable on or before the date the return was required to be filed, exceeds the amount so paid. For the purposes of the preceding sentence,