Li said ICBC targets a higher contribution to its individual credit revenue by adding 2 to 3 percentage points each year from last year's 10 percent.

Wu from CCB said 10 million active credit card users, or people who frequently use the card rather than leave them at home, can help CCB turn the business into a profitable one and the bank is just one step away from that.

"We expect to break even and make a profit next year based on our current card user numbers," Wu told Shanghai Daily.

CCB targets card numbers at 20 million at the end of this year, from 16 million at the moment.

Bank of Communications had planned to break even within three years when it launched its co-branded credit card with HSBC in 2005. But gaining market share takes priority now.

"If we stop promoting products and sit on the current card circulation scale, we are already making money," said a BoCom credit card manager. "We'd rather grow market share and boost the number of active card clients."

It seems obvious that most banks prefer to target economies of scale for their credit card business before profitability.

Guo Tianyong, a Central Univerity of Finance and Economics professor, said expanding card scale is one solution for banks to try to make profit in the sector and banks should diversify into other areas from the traditional channels.

He mentioned that banks should tap the growing power of the Internet such as online payments when promoting their credit cards.

A recent survey by qq.com showed that 33 percent of its users use credit cards, with white-collar workers among the most active users. This group has a monthly card-based consumption of 1,743 yuan (US$255), the survey found.

Amount rolled over

Banks make money from interest levied on cardholders who don't pay in full the outstanding amount, commission from merchants and annual fee.

CCB's Wu said clients aged between 30 and 45 years old with an annual salary of 100,000 yuan to 150,000 yuan are the main profit contributors to the bank. This group is willing to roll over the outstanding amount and pay interest on it.

Card users can just pay 10 percent of the bill before the due date. The bank will charge interest of 0.05 percent daily on the remaining 90 percent of the amount that is rolled over to the next due date.

When the stock market is booming, more card holders are likely to pay the minimum amount due so that they will have more cash to play in the stock market.

If card holders do not pay the minimum amount by the due date, banks will also charge a 10-percent penalty on the unpaid bill, besides the 0.05 percent daily interest.

But the issue of rollover debt triggered the question of risk control for the banks which can access the central bank's nationwide credit database on individuals, which was set up in January 2006.

The database covers 600 million individuals and more than 100 million of them have bank loan records at the end of 2007.