BEIJING-- China's foreign exchange regulator said Monday that the total surplus of Chinese banks' foreign exchange from bank-to-client transactions reached $26 billion in September.

In September, institutional and individual clients sold $142.6 billion in foreign currencies to banks while purchasing $116.6 billion, the State Administration of Foreign Exchange (SAFE) said in an online statement.

From January to September, more foreign currencies were sold than purchased through Chinese banks, resulting in $380.7 billion of foreign exchange surplus during the period, the statement said.

Foreign exchange surplus, which makes up part of China's foreign exchange reserves along with current account surplus and foreign direct investment inflow, does not include banks' own foreign exchange transactions or interbank transactions, according to the SAFE.

Last year, foreign exchange surplus made through Chinese banks' transactions with domestic clients increased 51 percent year-on-year to reach $397.7 billion, SAFE data showed.