CT Gen Stat § 12-227 (2020)
2020 Connecticut General Statutes|Title 12 - Taxation|Chapter 208 - Corporation Business Tax|Section 12-227 - Interest on refunds.

 (a) To any refunds granted as a result of overpayment of any tax imposed under this chapter or chapter 209, there shall, except as otherwise provided in subsection (b) or (c) of this section, be added interest at the rate of two-thirds of one per cent for each month and fraction of a month from the date of making such overpayment to a date, to be determined by the Commissioner of Revenue Services, preceding the date of the refund check by not more than thirty days.(b) (1) Notwithstanding any provision of subsection (a) of this section, in the case of an overpayment of tax reported on a tax return, no interest shall be allowed or paid under this section on such overpayment for any month or fraction thereof before (A) the ninety-first day after the last day prescribed for filing the tax return on which such overpayment was reported, determined without regard to any extension of time for filing, or (B) the ninety-first day after the date such return was filed, whichever is later.(2) Notwithstanding any provision of subsection (a) of this section, in the case of an overpayment of tax reported on an amended tax return, no interest shall be allowed or paid under this section on such overpayment for any month or fraction thereof before the ninety-first day after the date such amended tax return was filed. For purposes of this subsection, any amended return filed before the last day prescribed for filing the tax return for such year, determined without regard to any extension of time for filing, shall be considered as filed on such last day.(c) For purposes of this section, a tax return or amended tax return shall not be treated as filed until it is filed in processible form. A tax return or amended tax return is in a processible form if such return is filed on a permitted form, and such return contains the taxpayer's name, address and identifying number and the required signatures, and sufficient required information, whether on the return or on required attachments, to permit the mathematical verification of tax liability shown on the return.(1953, S. 1104d; 1957, P.A. 489, S. 2; 1959, P.A. 161, S. 1; 1963, P.A. 651, S. 15; P.A. 77-614, S. 139, 610; P.A. 89-343, S. 2, 17; May Sp. Sess. P.A. 94-4, S. 32, 85; P.A. 95-160, S. 64, 69; May 9 Sp. Sess. P.A. 02-1, S. 63.)History: 1959 act added exception for refunds due on estimated payments with tentative returns; 1963 act added exception for refunds due on payments on account of estimated tax; P.A. 77-614 substituted commissioner of revenue services for tax commissioner, effective January 1, 1979; P.A. 89-343 increased the rate of interest from 0.5% to 0.75% per month or fraction thereof; May Sp. Sess. P.A. 94-4 reduced interest rate from 0.75% to 0.66%, effective July 1, 1995, and applicable to taxes due and owing on or after said date; (Revisor's note: In 1997 a reference to Sec. 12-242c, repealed by P.A. 95-327, was deleted editorially by the Revisors); P.A. 95-160 revised effective date of May Sp. Sess. P.A. 94-4 but without affecting this section; May 9 Sp. Sess. P.A. 02-1 designated existing provisions as Subsec. (a) and amended same to delete exception re refunds due on certain estimated payments, modify time period for which interest is calculated, delete reference to years commencing on or after May 19, 1959, and make technical changes, added Subsec. (b) re limits on interest periods for overpayments of tax reported on returns and added Subsec. (c) re the form of returns, effective July 1, 2002, and applicable to tax returns and amended tax returns filed on or after July 1, 2001, and not allowed and paid before July 1, 2002 (Revisor's note: Sec. 64 of May 9 Sp. Sess. P.A. 02-1 provided as follows: “The intent of subsection (b) of section 12-227 of the general statutes, as amended by this act, is to properly indicate that current law does not authorize the Department of Revenue Services to allow or pay interest on an overpayment that is reported on a late tax return or on an amended return for any month or fraction thereof that is before the date on which such late return or such amended return is filed with the Department of Revenue Services.”).Cited. 31 CS 134.