摘要:For companies whose activities are selling of goods, profits depend on salesvolume. To increase the volume of sales, the company can sell its products inthe form of installment sale. This installment sales are at risk for decline inability of sellers is the buyer could not complete the remaining installmentpayments in accordance with the contract agreement. To reduce the risk borneby the company on the sale of the company can determine the amount of downpayment, length of term of repayment of installments and the amount of interestthat must be borne by the buyer. In determining the amount of interest that mustbe borne by the buyer, the employer must be able to determine the exact interestcalculation method. There are four methods used in calculating the installmentof interest, but in scientific writing, the writer tries to analyze the method andFlat Flat Annuitas theory in calculating interest installment sales.. PARAMULTI FINANCE annuitas falat method in the calculation of the installmentsale interest. Flowers large, ie Rp. 1,602,709.41 annuitas flat method, whereaswith the flat theory Rp. 2,830,762.00. And if the rest of the installments paid inmonth 5 the interest earned is Rp. 264,520.21