China's current-account surplus doubled in the third quarter from a year earlier to $102.3 billion, the State Administration of Foreign Exchange said on Thursday.

The nation's capital and financial account surplus was $5.7 billion for the quarter, according to the regulator. China's foreign exchange reserves increased by $107.3 billion in the period, excluding valuation changes.

The country's current-account surplus increased 30 percent to $204 billion in the first nine months of the year.