Missouri Code of State Regulations
Title 20 - DEPARTMENT OF COMMERCE AND INSURANCE
Division 4240 - Public Service Commission
Chapter 13 - Service and Billing Practices for Residential Customers of Electric, Gas, Sewer, and Water Utilities
Section 20 CSR 4240-13.025 - Billing Adjustments

(A) In the event of an overcharge, an adjustment shall be made for the entire period that the overcharge can be shown to have existed not to exceed sixty (60) consecutive monthly billing periods, or twenty (20) consecutive quarterly billing periods, calculated from the date of discovery, inquiry, or actual notification of the utility, whichever comes first;

(B) In the event of an undercharge, an adjustment shall be made for the entire period that the undercharge can be shown to have existed not to exceed twelve (12) monthly billing periods or four (4) quarterly billing periods, calculated from the date of discovery, inquiry, or actual notification of the utility, whichever was first;

(C) In the event of an undercharge, the utility shall offer the customer the option to pay the adjusted bill over a period at least double the period covered by the adjusted bill;

(D) No utility is required to issue a billing adjustment if the full amount of the adjustment is less than one dollar ($1);

(E) No billing adjustment shall be made if, upon test, an error in measurement is found to be within the limits prescribed by commission rules; and

(F) If evidence of tampering is found, or if the customer has made misrepresentations of the use of service, the utility shall calculate the billing adjustment period in accordance with the applicable statute of limitations for the prosecution of such claim after determining the probable period during which such condition existed from all related and available information.