I do not know of any CT DOB reg but here is what the NCUA has as to max rates
The Federal Credit Union Act and the NCUA Rules and Regulations set the maximum interest rate
federal credit unions can charge on loans and lines of credit at 15 percent per annum inclusive of all
finance charges. The Act permits NCUA to increase the interest rate above 15 percent for periods of up to
eighteen months. The current maximum interest rate is set at 18 percent. In determining whether a
particular charge constitutes a finance charge for purposes of compliance with the interest rate ceiling, we
generally follow the Reg Z interpretation of that term. If the credit union charges a fee only to those
borrowers who receive the loan, the fee is included as a finance charge and must be included in the APR
calculation.