If consumers shopped around for personal loans rather than going to a high street bank they could save £389 over the course of a loan - equivalent to £1.1 billion saved on loans taken out this year alone.
A personal loan from a high street provider costs an average 7.6 per cent APR, according to Sainsbury's Bank, while Sainsbury's Bank loan rates start from 6.1 per cent online.
"Consumer apathy and confusion are rife within the personal loan market. We estimate that over the next 12 months, around 3.3 million people will only contact one company when taking out their personal loan," said Steven Baillie, loans product manager at Sainsbury's Bank.
"And some people believe they have to take out a personal loan with the provider they have a current account with.
"This helps explain why high street banks, despite offering some of the most expensive unsecured personal loan rates, have approximately 50 per cent of the market."
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