The accumulated balance of China's social security fund will stand at 4.09 trillion yuan ($665 billion) by the end of 2013, according to the budget plan released by the Ministry of Finance on Tuesday.

The social security fund will receive revenue of 3.28 trillion yuan this year, 9.9 percent more than that of last year, which consists of insurance premiums of 2.47 trillion yuan and fiscal subsidies of 718 billion yuan.

In the meantime, there will be 2.79 trillion yuan of expenditure in 2013, up 16.8 percent on last year.

The fund will see a net increment of 491.5 billion yuan, adding its total balance to 4.09 trillion yuan by the end of this year, among which 2.4 trillion yuan will be the pension fund for enterprise employees.