Conn. Gen. Stat. § 12-589
(a)(1) Any company believing that it has overpaid any taxes imposed under section 12-587 may file a claim for refund in writing with the commissioner within three years from the due date for which such overpayment was made, stating the specific grounds upon which the claim is founded. Failure to file a claim within the time prescribed in this section constitutes a waiver of any demand against the state on account of overpayment. Not later than ninety days following receipt of such claim for refund the commissioner shall determine whether such claim is valid and if so, said commissioner shall notify the State Comptroller of the amount of such refund and the State Comptroller shall draw an order on the State Treasurer in the amount thereof for payment to such company. If the commissioner determines that such claim is not valid, either in whole or in part, he shall mail notice of the proposed disallowance to the claimant, which notice shall set forth briefly the commissioner's findings of fact and the basis of disallowance in each case decided in whole or in part adversely to the claimant. Sixty days after the date on which it is mailed, a notice of proposed disallowance shall constitute a final disallowance except only for such amounts as to which the claimant has filed, as provided in subdivision (2) of this subsection, a written protest with the commissioner.
(b)
(P.A. 80-71, S. 3, 30; P.A. 89-343, S. 4, 17; P.A. 93-361, S. 6; P.A. 95-26, S. 29, 52; P.A. 97-243, S. 61, 67; P.A. 13-232, S. 5.)
History: P.A. 80-71 effective July 1, 1980, and applicable to calendar quarters commencing on or after that date; P.A. 89-343 increased the rate of interest from 0.5% to 0.75% per month or fraction thereof; P.A. 93-361 made existing section Subsec. (b) and inserted a new Subsec. (a) providing for claims for refund of taxes upon overpayment; P.A. 95-26 amended Subsec. (b) to lower interest rate from 0.75% to 0.66%, effective July 1, 1995, and applicable to taxes due and owing on or after July 1, 1995, whether or not those taxes first became due before said date; P.A. 97-243 amended Subsec. (a) to provide for an administrative hearing with the department before taking an appeal to the Superior Court, establish the time for filing a claim and that failure to file within the time prescribed constitutes a waiver of any demand against the state on account of overpayment and made technical changes, effective July 1, 1997, and applicable to claims for refund filed on or after said date; P.A. 13-232 amended Subsec. (b) to designate existing provisions re interest on overpayments as new Subdiv. (1), delete former Subdivs. (1) and (2) re time period which elapses and add new Subdivs. (2) and (3) re timing of interest payment, effective July 1, 2013, and applicable to refunds issued on or after that date.