When interest payable on a personal loan is calculated using flat rate or flat balance method of interest calculation, it involves calculating interest on the entire loan principal amount throughout the loan tenure without taking into account the portion of the principal that has already been paid. The fact that the outstanding loan principal amount gradually decreases as monthly EMIs are paid is not taken into consideration by this method.
Contrary to this, the reducing balance method involves calculating interest only on the outstanding loan principal amount every month. Thus, as the outstanding loan amount decreases every month, the interest payable also decreases. Therefore, you will save on the total interest payout of the loan when interest is computed using reducing balance interest rates. LIC makes use of the reducing balance method to calculate the interest payable on its personal loans.