Christmas shoppers could receive higher than usual credit card bills as firms are accused of increasing rates to an 18-month high to take advantage of the festive period.

Firms are charging an average of 19.1%, which is calculated as 38 times higher than the 0.5% interest base rate set by the Bank of England. It is even higher than the increase credit card companies added on prior to Christmas last year when it hit 18.1%.

Credit card companies are taking advantage of families expected to fund Christmas with their cards due to the difficult economic environment, the Daily Mail said.

Observers will be suspicious that the firms want to raise money to fund the 0% interest deals available to customers and put back money lost through refunds to customers who were mis-sold payment protection insurance.

IMRG forecasts card spending online during the two weeks beginning December 3 will top £4.6bn.

Just under a billion of that figure, £920m, is expected to go through mobile devices, such as smartphones and tablets.

Money Facts finance expert Rachel Springall said: “Shoppers may be relying on their credit cards to cover Christmas this year; while this method may seem secure and straightforward, customers should be aware that the interest they are being charged is rising.

“Borrowers with a £5,000 debt on their card, who repay the minimum each month, will now repay an additional £692 over the life of the debt compared to a year ago.”