§ 513. Refunds. Whenever the commissioner shall determine that any
monies received under the provisions of this article were paid in error,
he may cause the same to be refunded or credited, with interest, in
accordance with such rules and regulations as he may prescribe, except
that no interest shall be allowed or paid if the amount thereof would be
less than one dollar. Such interest shall be at the overpayment rate set
by the commissioner pursuant to subdivision twenty-sixth of section one
hundred seventy-one of this chapter, or if no rate is set, at the rate
of six percent per annum, from the date when the tax, penalty or
interest to be refunded or credited was paid to a date preceding the
date of the refund check by not more than thirty days. Provided,
however, that for the purposes of this section, any tax paid before the
last day prescribed for its payment shall be deemed to have been paid on
such last day. Such moneys received under the provisions of this article
which the commissioner shall determine were paid in error, may be
refunded or credited out of funds in the custody of the comptroller to
the credit of such taxes provided an application therefor is filed with
the commissioner within four years from the time the erroneous payment
was made, except if an agreement under the provisions of section five
hundred ten (extending the period for determination of tax imposed by
this article) is made within the four-year period for the filing of an
application for refund provided for in this section, the period for
filing an application for refund shall not expire prior to six months
after the expiration of the period within which a determination may be
made pursuant to the agreement or any extension thereof.