CBA makes $2.1b in three months The Commonwealth Bank of Australia made a net profit of $2.1 billion during the September quarter. THE Commonwealth Bank of Australian made a $2.1 billion cash profit in the three months to the end of September after lifting revenues and keeping costs under control. The result follows a cash profit of $7.8 billion for the 12 months to June 30 this year. CBA on Wednesday also reported an unaudited $2.1 billion net profit for the quarter. The Commonwealth said a combination of solid revenue growth and cost discipline contributed to the quarterly result. But the bank's group net interest margin fell during the quarter as a result of the lower interest rate environment. Lower interest rates helped spur growth in business activity compared to a year ago, though total credit growth was modest due to higher levels of loan repayments. The Commonwealth said household deposit growth was strong during the quarter while stock market gains had provided a boost for the bank's wealth management business. Meanwhile, insurance premiums increased two per cent during the quarter. ASB, the bank's New Zealand subsidiary, recorded solid growth in customer deposits and advances thanks to an improving economy, although lending margins remained under pressure.