The Full Form of QAB is Quarterly Average Balance. QAB is the average of all the closing day balances of a bank account in a given quarter. It can be calculated by adding all closing day balances in a quarter and then dividing by the number of days in the quarter. Keeping Rs 90,000 in a bank account for 1 whole month is same as keeping Rs 30,000 for full 3 months i.e. 90,000 x 30 days = 30,000 x 90 days. Savings account holders are generally required to maintain a minimum QAB in their bank account and most banks levy penalty charges if the account holder does not maintain this balance. The QAB requirement varies from bank to bank, and is sometimes based on the account holder's location (urban, semi-urban and rural) and/or the account category (General, Privilege, Platinum, etc.). f. If the account holder fails to maintain QAB and the balance falls below the prescribed amount, the bank levies penalty or non-maintenance charges. Fees may vary from bank to bank. Account holders should be aware of QAB. They can either find it in the information brochure or ask the banker.