The director of research at the Prudential has urged the public to make their money work harder.
Darragh Leeson said that large numbers of people are "clingers" who simply leave their money in cash accounts.
As such they are not managing their money effectively, something he said was down to unfamiliarity with savings products.
Mr Leeson told the BBC: "Basically people are keeping it on deposit as a comfort blanket and that is in excess of the money you need for day to day living expenses and that rainy day money."
He added: "This is money that could be working harder rather than just languishing on the high street."
Mr Leeson estimated that around £107 billion was left in bank accounts with a poor rate of interest.
He concluded by saying: "These individuals are clingers, they are cash loving individuals not earning extra returns. They are worried about risk and many times they are too busy to get their spare cash out of poor performing savings accounts and they tend to find managing their accounts all too confusing."
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