The amount of assets held by major local lenders totaled 2,031.3 trillion won (US$1.82 trillion) at the end of December last year, up 62.3 trillion won from 1,969.0 trillion won the previous year, according to the data by the Financial Supervisory Service (FSS).
KB Kookmin Bank, the flagship unit of the country's No. 2 banking firm KB Financial Group Inc., held the largest 280.3 trillion won, followed by Woori Bank with 265.6 trillion won and Shinhan Bank with 254 trillion won, the data showed.
The Industrial Bank of Korea and Korea Development Bank, two major state-run policy lenders, saw their assets come in at 205.7 trillion won and 167.1 trillion won, respectively.
The on-year increase in banks' assets came as the industry competition among local lenders has become fiercer amid the launching of new players, market watchers said.
Last year, NongHyup Financial Group Inc. was launched in March with seven affiliates, including the banking unit NongHyup, which is short for the National Agricultural Cooperatives Federation. In the following month, Hana Financial Group Inc., the No. 4 banking firm, completed buying the fifth-largest lender Korea Exchange Bank.
The tougher market has led banks to competitively increase lending. The total amount of bank loans reached 1,390 trillion won as of end-2012, up 3.3 trillion won from a year earlier, the data showed.
But banks' bad loans shrank sharply, as the regulator has ramped up efforts to stem potential defaults the banks might incur on soured debts, especially when the country's been facing a record high household debt worth 959.4 trillion won as of December.
In separate data, meanwhile, the combined assets held by local insurance companies also hiked to 699.6 trillion won, compared with 566.1 trillion won over the cited period, the FSS said.