There’s no such thing as a free bank, according to Which?.

It cites low credit interest, high overdraft charges and big fees on spending abroad as examples of why, despite not paying a monthly sum for our current accounts, banking is not free.

Which? claims that consumers could be spending as much as £1,140 a year on unauthorised overdraft charges if they bank with Santander.

It also found First Trust charges customers £185 a year for using a £200 authorised overdraft six days a month, while Coventry BS has no charge for a £250 authorised overdraft.

Which? also says each bank has different ways of charging for overdrafts, making it difficult for consumers to compare accounts.

Which? looked at the typical cost of a current account for customers who have an average balance of £1,500, and who make one short trip overseas each year. It found that lost interest and fees for using their card abroad could be costing consumers as much as £57 a year and much more for those who travel overseas regularly.

Which? chief executive, Peter Vicary-Smith, said: “Contrary to popular belief