A public utility shall not apply delayed payment charges on a customer's account if the scheduled payment was made by the customer within twenty days from the date the billing was sent to the customer. Delayed payment charges on a customer's account shall not exceed one and one-half percent per month of the past-due amount. This section shall not apply to telecommunications service providers registered pursuant to section 476.95A.
Iowa Code § 476.54
83 Acts, ch 127, §37; 2018 Acts, ch 1160, §16