A consumer group has warned that the costs associated with using a credit card have increased because providers are using a raft of new charges to make money from customers.

Last year, credit card companies were told by the Office of Fair Trading that the highest penalty fee they could charge people in the future would be £12.

However, Which? said that since the ruling, other fees and charges levied on customers have "notably increased".

The organisation said that some credit card providers have introduced annual fees of up to £24 a year, while the amount charged to people transferring a balance from one card to another has risen from a typical 2% to 3% in some cases.

The group claims that some firms have also reduced the minimum repayments people have to make, so that those who only repay the minimum amount each month pay more interest before they clear their balance.

It also said that some companies have changed the order in which repayments are made, so that people pay off debt that they are paying the lowest interest rate on first, before debt on which they are being charged higher rates is reduced.

And Which? said some providers have now introduced low usage fees, charging people who do not use their card regularly penalties of up to £35, while others have started fining consumers up to £12 if they fail to inform them that they have changed their address.

The group added that some cards now charge higher interest rates and fees for cash withdrawals, and some providers even treat the purchase of vouchers as if they are cash withdrawals, on which interest rates are higher.

Martyn Hocking, editor of Which? Money, said: "Credit card providers seem to be resorting to a raft of ingenious methods to recoup lost revenue following the OFT crackdown on penalty fees."

He urged people to check the small print of their agreements and to make sure they know which charges apply to them if they fall foul of the rules.

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