(1)  An electricity retailer may, on a basis approved by the Regulator –

(a) impose charges on a tariff customer for late payment of an electricity account if the customer has not paid the amount due by the due date for payment fixed in the relevant electricity account; and

(b) charge the tariff customer interest on that amount from the due date until the date of payment.

(2)  Subregulation (1) does not apply if –

(a) the electricity retailer and the tariff customer have entered into a payment plan under regulation 19 in respect of the amount due; and

(b) the amount due relates to electricity supplied to premises that are used wholly for residential purposes.