Conn. Gen. Stat. § 12-665

A surcharge is hereby imposed on the rental or leasing, for a period of thirty consecutive calendar days or less, of a passenger motor vehicle by any person licensed pursuant to section 14-15 . Said surcharge shall be in addition to any tax otherwise applicable to any such transaction. No surcharge shall be imposed under this section for the rental or leasing of a motor vehicle pursuant to a written agreement having a term of more than thirty days.