Since electric service is used prior to meter reading and billing, MEC may require a deposit prior to connection on standard billing as a guarantee of payment. The security deposit will be applied to your final billing and any net balance refunded, or if 12 consecutive billings have been paid on time, your deposit will, likewise, be refunded. Interest will be paid on deposits equal to the rate paid on the United States National Bank's Passbook Savings Account at the end of the previous month. If a deposit is held for one year, accrued interest will be paid by a credit to the customer’s account. If held less than one year, interest will be prorated.