Consumers could save themselves hundreds of euro in interest payments by shopping around before signing up for a new credit card, the Irish Financial Services Regulatory Authority (Ifsra) warned yesterday.

The interest charged on new purchases by different cards ranges from 9.9 per cent with Permanent TSB's Ice card to 18.9 per cent with AIB's Classic account and American Express's Blue card, according to a survey by the regulator. With cash withdrawals, the interest charges, known as APR, range from 11.6 per cent to 20.68 per cent .

"Credit cards are convenient if you use them wisely," says Ifsra spokeswoman Jill Forde. "They are an expensive way of borrowing but for short-term needs they are useful."

The first thing to do when choosing a credit card is to assess which type of user you are, says Ms Forde.

If you tend to pay off your bill in full at the end of every month, you should look for a card that offers low fees and charges. National Irish Bank's standard and gold cards currently have no extra charges. The interest rate isn't as important, although you may want to consider the length of the interest-free period, she says.

However, if you usually carry your balance over, it is important to look for a card that offers a low interest rate. According to the survey, the lowest APR is currently being offered on Permanent TSB's Ice card, with a charge of 9.9 per cent on purchases.

For people who have built up a large backlog of credit card debt, Ms Forde has three suggestions: "Ideally, they should stop using their card and pay off the outstanding balance," she says. "Alternatively, they can either take out a personal loan or transfer the balance to another card, which is offering interest-free balance transfers."

Ulster Bank currently offers 0 per cent APR for nine months through its standard card, while Tesco Personal Finance's Classic card won't charge any interest for six months.

However, when doing this, it is important to note that the interest-free period is only for a limited time and, after that, the charge may rise to a level above that charged by other cards, says Ms Forde.

It is also important to consider the extra charges you may have to pay if you exceed your credit limit or are late making a payment. Late payment fees range from zero to €15.24, while the charge for exceeding your credit limit can be as much as €12.70.

The survey compared 19 credit cards supplied by 11 different financial institutions.