Foreign currency deposits at banks in South Korea dipped for a fifth consecutive month in September, hitting the lowest level in 15 months, central bank data showed Thursday.

Outstanding foreign currency deposits held by local residents came to $59.19 billion as of the end of last month, down $500 million from the previous month, according to the data from the Bank of Korea.

Local residents include firms and foreign nationals who have stayed in the country for more than six months. The figure excludes inter-bank foreign currency deposits.

The on-month drop was largely attributed to a sharp fall in Chinese yuan deposits, which tumbled $1.2 billion on-month to $9.43 billion.

The figure also marks the lowest level since $9.91 billion in April 2014, according to the BOK.

"Yuan deposits dropped as deposits withdrawn following maturity were not redeposited," it said in a press release.

Deposits in the U.S. greenback, on the other hand, gained $760 million to $43.47 billion as of end-September.

Foreign currency deposits held by local branches of South Korean banks gained $1.29 billion on-month to $42.97 billion while those held by overseas branches tumbled $1.79 billion with South Korean bank branches in China alone losing $1.19 billion. (Yonhap)