Section R. 460.126a - Billing errorRule 26a.
(1) If a utility overcharges a customer due to a billing error, then the utility shall refund or credit the amount of the paid overcharge to the customer. Paid overcharges shall be credited to a customer with 5% APR interest, commencing on the sixtieth day following payment. A utility is not required to adjust, refund, or credit an overcharge plus 5% APR interest for more than the 3 years immediately preceding discovery of the billing error, unless the customer is able to establish an earlier date for commencement of the error.(2) Upon customer request, paid overcharges for billing errors greater than $10.00 shall be refunded within 30 days of the request.(3) If a utility undercharges a customer, in cases that do not involve unauthorized use of utility service, the utility may back bill the customer for the amount of the undercharge during the 12-month period immediately preceding discovery of the error, and the utility shall offer the customer reasonable payment arrangements for the amount of the back bill, which shall allow the customer to make installment payments over a period at least as long as the period of the undercharge. The utility shall take into account the customers financial circumstances when setting payment amounts.Mich. Admin. Code R. 460.126a
2017 MR 22, Eff. 12/11/2017