N.Y. GCM Law § 130

§ 130. Assessment. (a) Assessment date.--The amount of tax which a\nreturn shows to be due, or the amount of tax which a return would have\nshown to be due but for a mathematical error, shall be deemed to be\nassessed on the date of filing of the return (including any amended\nreturn showing an increase of tax). In the case of a return properly\nfiled without computation of tax, the tax computed by the director of\nfinance shall be deemed to be assessed on the date on which payment is\ndue. If a notice of deficiency has been mailed, the amount of the\ndeficiency shall be deemed to be assessed on the date specified in\nsubdivision (b) of section one hundred twenty-nine if no petition to the\ndirector of finance is filed, or if a petition is filed, then upon the\ndate when a decision of the director of finance establishing the amount\nof the deficiency becomes final. If an amended return or report filed\npursuant to section one hundred twenty-seven concedes the accuracy of a\nfederal adjustment, change or correction, any deficiency in tax under\nthis title resulting therefrom shall be deemed to be assessed on the\ndate of filing such report or amended return, and such assessment shall\nbe timely notwithstanding section one hundred thirty-one. If a report\nfiled pursuant to section one hundred twenty-seven-A concedes the\naccuracy of a state change or correction of sales and compensating use\ntax liability, any deficiency in tax under this title resulting\ntherefrom shall be deemed assessed on the date of filing such report,\nand such assessment shall be timely notwithstanding section one hundred\nthirty-one. If a notice of additional tax due, as prescribed in\nsubdivision (e) of section one hundred twenty-nine, has been mailed, the\namount of the deficiency shall be deemed to be assessed on the date\nspecified in such subdivision unless within thirty days after the\nmailing of such notice a report of the federal change or correction or\nan amended return, where such return was required by section one hundred\ntwenty-seven, is filed accompanied by a statement showing where in such\nfederal determination and such notice of additional tax due are\nerroneous. If a notice of additional tax due, as prescribed in\nsubdivision (h) of section one hundred twenty-nine, has been mailed, the\namount of the deficiency shall be deemed to be assessed on the date\nspecified in such subdivision unless within thirty days after the\nmailing of such notice a report of the state change or correction, or a\ncopy of an amended return or report, where such copy was required by\nsection one hundred twenty-seven-A, is filed accompanied by a statement\nshowing wherein such state determination and such notice of additional\ntax due are erroneous. Any amount paid as a tax or in respect of a tax,\nother than amounts paid as estimated income tax, shall be deemed to be\nassessed upon the date of receipt of payment, notwithstanding any other\nprovisions.\n (b) Other assessment powers.--If the mode or time for the assessment\nof any tax under this title (including interest, additions to tax and\nassessable penalties) is not otherwise provided for, the director of\nfinance may establish the same by regulations.\n (c) Estimated income tax.--No unpaid amount of estimated tax under\nsection one hundred sixteen shall be assessed.\n (d) Supplemental assessment.--The director of finance may, at any time\nwithin the period prescribed for assessment, make a supplemental\nassessment, subject to the provisions of section one hundred twenty-nine\nwhere applicable, whenever it is ascertained that any assessment is\nimperfect or incomplete in any material respect.\n (e) Cross reference.--For assessment in case of jeopardy, see section\none hundred forty-two.\n