Households could be sitting on hundreds of pounds in forgotten bank accounts and savings deals.
In fact Brits have around £4.5billion unclaimed, according to lost assets firm Gretel.
The average person with a lost account has £450 to claim, but some have up to £1,500, The Sun reports.
Up to 10million of us have this unclaimed cash.
If you're lucky the money could even be earning interest.
The Mirror reported last month that one woman was stunned to learn the £2.50 she had in a 60-year-old account she had as a girl had accrued 100 per cent interest and is now worth £250.
How to track down a lost account
If you know the name of a bank, building society or savings firm you might have money in, contact them first.
The website Accountdetective.co.uk can tell you if any of these firms have rebranded, and provide their contact details
If you cannot remember the details of an old account, or your bank or building society cannot find it, you can use a service called My Lost Account.
The more details you have the better.
Gretel has its own free online service that tries to track down forgotten accounts for consumers.
Tens of thousands of young people are unaware they could have £1,000 sitting in a Child Trust Fund (CTF) dating as far back as 2002.
You can use this online tool to check if you have a forgotten account.
The Share Foundation charity also runs a free finding service.
If your claim is not successful you can complain to the Financial Ombudsman Service if you still believe you are owed money.
You can also see if you have been left anything by a relative by going online.
The government keeps a list of deceased people with money still left to be claimed – stretching back up to 30 years.
You can track down a lost pension by using tools such as the Pension Tracing Service.
One of the biggest pots of unclaimed cash is with National Savings & Investments (NS&I), Britain's biggest savings firm.
In fact there is more than £600million sitting in old NS&I accounts ready to be claimed.
The cash ends up being put into NS&I's 'residual account'.
This is a sort of graveyard account where NS&I puts your money when savings deals expire and you don't claim them.
If NS&I can't work out how to contact you, perhaps because you've moved house and not said, it sweeps all the cash into one big account. Then it waits for you to claim it.
To put it in context, £672million is roughly the same as the annual GDP of Thailand - or more than two New Zealands.
If you think you might have an old NS&I savings deal you never claimed, the first thing to do is see if you can locate any paperwork with details on it.
If you can't, then you can use NS&I's tracing service.
To do this, you'll need to print out and complete an account tracing form and post it to Tracing Service, NS&I, Sunderland SR43 2SB.
