§ 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 or six hundred fifty-nine-a 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 or six hundred fifty-nine-a,
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.