Section 11-524. Interest on underpayment

(a) General. If any amount of tax
  is not paid on or before the last date prescribed in  this  chapter  for
  payment,  interest  on  such  amount at the underpayment rate set by the
  commissioner of finance pursuant to section 11-537 of this chapter,  or,
  if  no  rate is set, at the rate of seven and one-half percent per annum
  shall be paid for the period from such  last  date  to  the  date  paid,
  whether  or  not any extension of time for payment was granted. Interest
  under this subdivision shall not be paid if the amount thereof  is  less
  than one dollar.
    (b) Exception as to estimated tax. This section shall not apply to any
  failure to pay estimated tax under section 11-512 of this chapter.
    (c)  Exception for mathematical error. No interest shall be imposed on
  any underpayment of tax due solely to mathematical error if the taxpayer
  files a return within the time prescribed in this chapter (including any
  extension of time) and pays the  amount  of  underpayment  within  three
  months after the due date of such return, as it may be extended.
    (d)   Suspension   of   interest  on  deficiencies.  If  a  waiver  of
  restrictions on assessment  of  a  deficiency  has  been  filed  by  the
  taxpayer,  and  if  notice and demand by the commissioner of finance for
  payment of such deficiency is not made  within  thirty  days  after  the
  filing  of such waiver, interest shall not be imposed on such deficiency
  for the period beginning immediately after such thirtieth day and ending
  with the date of notice and demand.
    (e) Tax reduced by carryback. If the the amount of tax for any taxable
  year is reduced by reason of a carryback of a net operating  loss,  such
  reduction in tax shall not affect the computation of interest under this
  section  for the period ending with the filing date for the taxable year
  in which the net operating  loss  arises.  Such  filing  date  shall  be
  determined without regard to extensions of time to file.
    (f) Interest treated as tax. Interest under this section shall be paid
  upon  notice and demand and shall be assessed, collected and paid in the
  same manner as tax. Any reference in this chapter to the tax imposed  by
  this  chapter  shall be deemed also to refer to interest imposed by this
  section on such tax.
    (g) Interest on penalties or  additions  to  tax.  Interest  shall  be
  imposed  under  subdivision  (a)  of  this  section  in  respect  of any
  assessable penalty or addition to tax only if such assessable penalty or
  addition to tax is not paid within ten days from the date of the  notice
  and  demand  therefor  under  subdivision  (b) of section 11-532 of this
  chapter, and in such case interest shall be imposed only for the  period
  from such date of the notice and demand to the date of payment.
    (h)  Payment  within  ten  days after notice and demand. If notice and
  demand is made for payment  of  any  amount  under  subdivision  (b)  of
  section  11-532  of  this chapter, and if such amount is paid within ten
  days after the date of such  notice  and  demand,  interest  under  this
  section  on the amount so paid shall not be imposed for the period after
  the date of such notice and demand.
    (i) Limitation on assessment and collection. Interest prescribed under
  this section may be assessed and collected at any time during the period
  within which the tax or other amount to which such interest relates  may
  be assessed and collected, respectively.
    (j)  Interest  on erroneous refund. Any portion of tax or other amount
  which has been erroneously refunded, and which  is  recoverable  by  the
  commissioner  of  finance,  shall bear interest at the underpayment rate
  set by the commissioner of finance pursuant to section  11-537  of  this
  chapter,  or,  if  no  rate  is  set,  at the rate of seven and one-half
  percent per annum from the date of the payment of the refund,  but  only

  if  it  appears  that  any  part of the refund was induced by fraud or a
  misrepresentation of a material fact.
    (k)  Satisfaction  by credits. If any portion of a tax is satisfied by
  credit of an overpayment, then no interest shall be imposed  under  this
  section  on  the  portion  of the tax so satisfied for any period during
  which, if the credit  had  not  been  made,  interest  would  have  been
  allowable with respect to such overpayment.