La. R.S. 45:846

No person engaged in furnishing gas, water or electricity to consumers, to be paid for by meter measure, shall charge or receive, from any patron or consumer, payment for more gas, electricity or water than the meter indicates has been used by the consumer at the time for which payment is made and received; provided, however, that estimated bills may be rendered to and payment thereof collected from consumers for such periods and on such basis as may be approved or prescribed by the Louisiana Public Service Commission or other regulatory authority having jurisdiction over the person furnishing such service. The minimum charge contracted for with the municipalities shall not be affected.