R.I. Gen. Laws § 31-36-11.1: Interest on overpayments.

If it shall be determined that an overpayment has been made with respect to the tax provided for in this chapter, the amount of the overpayment shall bear interest at the annual rate established by § 44-1-7.1. The acceptance of the check shall be without prejudice to any right of the taxpayer to claim any additional overpayment and interest.