Outstanding household loans from lenders came to 776.3 trillion won ($728.6 billion) as of the end of March, according to the data by the Bank of Korea.
The total marked a 4.3 trillion won increase from a month earlier, the largest on-month growth since November last year, when it posted a 6.7 trillion won gain.
Mortgages climbed by 2.8 trillion won on-month to a four-month high of 576 trillion won last month due to a steady rise in home transactions, especially in the capital city.
The BOK said other bank loans, including lending through an overdraft line of credit, gained 1.5 trillion won on-month to 199.4 trillion won.
The central bank said a growing number of people borrowed money to buy houses last month before the new debt service ratio rules went into effect for a trial run on March 26.
As a result, transactions of apartments in the capital city of Seoul reached 14,000 in March, up sharply from 7,000 deals a year ago.
Under the tightened DSR guidelines, lenders will check borrower's monthly debt obligations, which include overdraft bank accounts and credit card loans, making it harder for people to take out fresh loans.
The South Korean government has churned out a series of measures to tighten mortgage rules for owners of multiple homes as part of efforts to ensure mounting household debt does not hurt the nation's economy.(Yonhap)