Section 11-675. Interest on underpayment

1. General. If any amount of tax is
  not paid on or before the last date prescribed in whichever of the named
  subchapters  is  applicable  for payment, interest on such amount at the
  underpayment rate set by the commissioner of finance pursuant to section
  11-687 of this subchapter, 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.
    2. Exception as to estimated tax. This section shall not apply to  any
  failure to pay estimated tax under subchapter two or subchapter three of
  this chapter.
    3.  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  whichever  of  the  named
  subchapters is applicable (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.
    4. 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.
    5.  Tax  reduced  by carry back. If the amount of tax under subchapter
  two for any taxable year is reduced by reason of a carryback  of  a  net
  operating loss or a capital 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  or  capital  loss  arises.  Such  filing  date shall be determined
  without regard to extensions of time to file.
    6. 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 the taxes under the named subchapters. Any  reference  in
  this  subchapter  to the tax imposed by the named subchapters, or any of
  them, shall be deemed also to refer to interest imposed by this  section
  on such tax.
    7. Interest on penalties or addition to tax. Interest shall be imposed
  under  subdivision  one in respect to 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 two of section  11-683  of  this  subchapter  in  such  case
  interest  shall  be  imposed  only  for the period from such date of the
  notice and demand to the date of payment.
    8. Payment within ten days after notice  and  demand.  If  notice  and
  demand  is  made  for  payment  of  any  amount under subdivision two of
  section 11-683 of this subchapter, 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.
    9. 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.
    10. 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 11-687 of this
  subchapter, 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.
    11. 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.