Maryland Tax - General Section 13-603

      (a)      Except as otherwise provided in this section, if a claim for refund under § 13-901(a)(1) or (2) or (d)(1)(i) or (2) of this title is approved, the tax collector shall pay interest on the refund from the 45th day after the claim is filed in the manner required in Subtitle 9 of this title to the date on which the refund is paid.

      (b)      A tax collector may not pay interest on a refund if the claim for refund is:

            (1)      made under any provision other than § 13-901(a)(1) or (2) or (d)(1)(i) or (2) of this title;

            (2)      based on:

                  (i)      an error or mistake of the claimant not attributable to the State or a unit of the State government;

                  (ii)      withholding excess income tax;

                  (iii)      an overpayment of estimated financial institution franchise tax or estimated income tax; or

                  (iv)      an overpayment of Maryland estate tax based on an inheritance tax payment made after payment of Maryland estate tax; or

            (3)      made for Maryland estate tax or Maryland generation-skipping transfer tax more than 1 year after the event on which the claim is based.