More South Koreans reported having overseas financial accounts worth more than 1 billion won ($899,000) in 2013 amid the government’s move to root out tax evasion, the tax agency said Tuesday.

The National Tax Service said 678 individuals and institutions reported holding a combined 22.8 trillion won in 6,718 overseas accounts as of July this year, up 22.8 percent from end-December 2012.

Market watchers said the rise came as the government has been making efforts to impose a tougher surveillance on overseas accounts to root out tax evasion and raise tax revenue for its costly welfare programs.

The NTS said individuals had 1,124 accounts worth 2.5 trillion won, which translates into an average of 8 billion won per account.

Institutions held a comparable figure of 5,594 accounts worth 20.3 trillion won.

Of such accounts, 25 percent contained assets worth more than 5 billion won, while 44 percent contained assets smaller than 2 billion won.

The report was made from 123 countries, compared to 115 countries tallied a year earlier. Of them, 13 were designated as tax havens by the Organization for Economic Cooperation and Development.

Singapore-based accounts held the biggest amount of assets, followed by those in Bahrain, Switzerland, the Philippines and Belgium.

The NTS added it is also investigating 47 individuals for alleged tax evasion through overseas accounts, adding it will impose a 10-percent fine on the assets if their illegal deeds are revealed.

All South Koreans with overseas financial accounts worth more than 1 billion won, meanwhile, will be obligated to report their overseas assets and their sources starting next year, the Ministry of Strategy and Finance said Monday. (Yonhap News)