Section 346.102 - Permissible Interest Rate for Billing Cycle(a) A revolving credit account that provides for equal billing cycles may provide for interest for a billing cycle at the rate equal to one-twelfth of the applicable annual interest rate on the average daily balance of the account during that billing cycle.(b) In any 12-month period, billing cycles are considered to be equal if: (1) the number of billing cycles in the period does not exceed 12; and(2) the difference between the length of the longest and the shortest billing cycles in the period does not exceed eight days. Acts 1997, 75th Leg., ch. 1008, Sec. 1, eff. 9/1/1997.