Savers are throwing away more than £15bn in interest a year, according to new data.

The latest Bank of England figures, published on Friday, revealed £303.83bn is kept in accounts making no interest at all, including current accounts.

Analysis by Hargreaves Lansdown calculated that figure could mean savers are missing out on a collective £15.07bn in interest.

The company’s research revealed that 22% of people have never switched savings accounts, 44% don’t know what they’re making on all their savings, and 40% have no plans to ever switch. More than half of savers (52%) haven’t switched their savings in a year.

Sarah Coles, head of personal finance, Hargreaves Lansdown, said: “If everyone switched their savings into the leading easy access savings account (excluding bonuses), they could earn £15.07bn in interest over the next year. It’s an eye-watering sum to be binning without a second thought.”

Part of the problem is that savings rates are much higher than they used to be meaning those with poor accounts - such as easy access savings accounts and ISAs with high street banks - are missing out more than ever.

Savers who tracked down a decent deal when they first opened an account, will have ended up being penalized as the interest paid out shrank or dwindled to nothing.

Ms Coles said: “The penalty for leaving savings languishing rose rapidly with savings interest rates, and although rates have fallen from the peak, the penalty has continued to climb, because the money gathering dust in these accounts has been gradually building. It’s up an eye-watering £49.78 billion since December 2023.”

Another huge chunk of cash is sitting in current accounts earning no interest at all from day one. The average (median) household has £3,328 languishing in current accounts, and the highest-earning 20% have an average of £9,864.

• Research figures based on Opinium survey conducted for HL, September 2024.