The monthly average daily balance (MADB) is the money you must maintain in your savings account to avoid a penalty fee. To understand it clearly, emphasis should be given to “average.” Therefore, if the MADB of a savings account is Php 2,000 (as in the case of BDO ATM Savings), it doesn’t mean you should maintain a balance of Php 2,000 in your account every day of the month. Again, we’re talking about the average. In this case, MADB can be computed by adding the remaining balance in your account for each day in the month and dividing the total by the number of days in the month. For example, from November 1 to 15, your ATM Savings had a Php 2,000 balance left untouched throughout that time frame. Then, come November 16, you withdrew Php 300 from your account and failed to make any deposit throughout the month (i.e., 15 days–from November 16 to November 30). At the end of November, your monthly average daily balance would be: (Php 2,000 x 15) + (Php 1,700 x 15) = 55,000 55,000/ 30 = Php 1,850 As the table below suggests, you fall short of the required minimum average daily balance (i.e., Php 2,000) for ATM Savings. However, failing to meet the MADB once is insufficient for you to incur fees. Only if you don’t meet the required MADB for two consecutive months will you be charged Php 300, also known as the “Falling Below Minimum Balance Fee.” In the case of BDO Passbook Savings, where the MADB is twice the minimum initial deposit (see table above), account holders must deposit an additional Php 5,000 within the month of opening the account to meet the required MADB of Php 10,000.