Savings alert as Britons could be missing out on average £450 because they don't know about it - how to claim yours

Many bank accounts have been closed to new savers for over a decade but still hold people's cash, such as Northern Rock or Egg.

The money in a dormant savings account is simply left there. It will earn interest at whatever rate the bank has set.

As the Bank of England base rate remains at 5.25 per cent, savers are urged to secure a similar rate on their savings to make the most out of their money.

A number of fixed-rate savings bonds currently pay five per cent-plus – on these accounts their return is guaranteed and people will be earning more than twice the current rate of inflation.

An estimated 20 million people have a lost bank account in the UK, according to research by Which?

There are various reasons as to how someone may lose a savings account.

Sarah Coles, personal finance expert at Hargreaves Lansdown said: "Plenty of people can end up opening multiple accounts. We might have several savings accounts, possibly because we want to fix our savings for different periods, or to have separate pots for different goals.

“If you have a holiday fund in a specific account, take the holiday, and leave a couple of quid in the account, it’s easy to forget all about it.”

Another common reason for forgotten accounts is savings accounts opened for children by family members that – by the time the child turns 18 and wants the money – have been completely lost.

Coles continued: "It’s then surprisingly easy to lose track over the years if we’re not completely on the ball with filing the paperwork, or updating our address with every single provider when we move.

“It means we can end up trailing multiple accounts in our wake that we’ve forgotten about entirely."

How to find a lost account

Savers can trace lost or dormant bank and savings accounts using the My Lost Account service, which is run by the British Bankers' Association, Building Societies Association and National Savings and Investments (NS&I).

All people need to do is complete one online form free of charge.

They could also try Gretel to find old bank accounts.

They will need to enter their name, current address, and date of birth to make a search - and be able to verify past addresses.

According to Moneyfacts, these are a list of dormant accounts: