Section 682. Assessment

-- (a) Assessment date.--The amount of tax which a
  return shows to be due, or the amount of tax which a return  would  have
  shown  to  be  due  but  for  a mathematical or clerical error, shall be
  deemed to be assessed on the date of filing of the return (including any
  amended return showing an increase of tax). In  the  case  of  a  return
  properly  filed  without  computation  of  tax,  the tax computed by the
  commissioner shall be deemed to be assessed on the date on which payment
  is due. If a notice of deficiency has been mailed,  the  amount  of  the
  deficiency  shall  be  deemed  to  be  assessed on the date specified in
  subsection (b) of section six hundred eighty-one if no petition  to  the
  division  of  tax appeals is filed, or if a petition is filed, then upon
  the date when a determination or decision rendered in  the  division  of
  tax  appeals establishing the amount of the deficiency becomes final. If
  an amended return or  report  filed  pursuant  to  section  six  hundred
  fifty-nine  concedes the accuracy of a federal change or correction, any
  deficiency in tax under this article resulting therefrom shall be deemed
  to be assessed on the date of filing such report or amended return,  and
  such  assessment  shall  be  timely  notwithstanding section six hundred
  eighty-three. If a notice  of  additional  tax  due,  as  prescribed  in
  subsection  (e)  of section six hundred eighty-one, has been mailed, the
  amount of the deficiency shall be deemed to  be  assessed  on  the  date
  specified in such subsection unless within thirty days after the mailing
  of  such  notice  a  report  of  the  federal change or correction or an
  amended return, where such return was required by  section  six  hundred
  fifty-nine,  is  filed  accompanied  by a statement showing wherein such
  federal  determination  and  such  notice  of  additional  tax  due  are
  erroneous.  Any  amount paid as a tax or in respect of a tax, other than
  amounts withheld at the source or paid as estimated income tax, shall be
  deemed  to  be  assessed  upon  the  date   of   receipt   of   payment,
  notwithstanding any other provisions.
    (b)  Other  assessment powers.--If the mode or time for the assessment
  of any tax under this article (including interest, additions to tax  and
  assessable  penalties) is not otherwise provided for, the tax commission
  may establish the same by regulations.
    (c) Estimated income tax.--No unpaid amount of estimated tax shall  be
  assessed.
    (d)  Supplemental  assessment.--The  tax  commission  may, at any time
  within  the  period  prescribed  for  assessment,  make  a  supplemental
  assessment,  subject to the provisions of section six hundred eighty-one
  where applicable, whenever it is  ascertained  that  any  assessment  is
  imperfect or incomplete in any material respect.
    (e)  Cross reference.--For assessment in case of jeopardy, see section
  six hundred ninety-four.