By Paul Lewis
Presenter, Radio 4's Money Box
You can only pay for 20p worth of goods with copper coins
Many of us put our small change into an old jam jar or pot to stop it making holes in our pockets or bursting out of our purses.
But when the containers are all full how do you turn several kilograms of steel and cupro-nickel coins into currency you can spend easily?
One way is to use the coin changing machines that are spreading through our supermarkets.
Coinstar claims its customers make 200,000 visits a week to its 1,500 machines. It says, at each visit, they tip small change worth an average £28 into the hopper.
Changed at a charge
But the service is not free. At the moment the machine will charge a 'processing fee' of 7.9%. So £10 of small change will be converted to a voucher for £9.21.
There are 1,500 of these machines in supermarkets around the UK
And Coinstar told Radio 4's Money Box that it is in the process of raising its charges from 7.9% to 8.9% - an extra penny off each pound changed.
A spokesman said: "The fee covers the costs of processing the money, collecting it, a field team of engineers, and a small profit for Coinstar and the supermarkets.
"The costs of processing and security have gone up."
Paying for convenience
Nick Harris, Coinstar's operations manager, told the programme that customers were happy to pay the new fee.
"The fee's never been an issue. Our customers don't object to it. The supermarkets receive a portion of the fee and they also benefit from the sales.
"People tend to buy treats. It's found money and people are happy to spend it."
The voucher can be used to pay in the supermarket or cashed at the customer service till.
Taking cash to the bank
Coinstar is cashing in on the growing reluctance of banks to take change.
LEGAL TENDER GUIDELINES
£5 (Crown) - for any amount
£2 - for any amount
£1 - for any amount
50p - for £10 or less
25p (Crown) - for £10 or less
20p - for £10 or less
10p - for £5 or less
5p - for £5 or less
2p - for 20p or less
1p - for 20p or less
Source: Royal Mint
They will only do it for their own customers and insist it has to be sorted into different denominations and put in their own bags in set amounts - £1 for coppers, £5 for silver, and so on.
Some banks limit the number of bags they will take per day, others will refuse to take bags of change at busy times and Royal Bank of Scotland told Money Box it may charge regular coin changers £2.
HSBC takes a different view. It has free coin changing machines in 200 of its branches and Barclays says it now has 15. They count coins and credit accounts immediately.
Another option is to try to spend it. But there are legal rules on how much shops have to accept - though many will accept more.
What is in your piggy bank?
But there may be an easier way.
Blogger James Watson collects the items rejected by coin machines
James Watson studies Coinstar machines and collects the items people try to put into them which are rejected - a lot of foreign coins, a farthing a century old, washers, and a shelf support. Photographs of his found items appear on his blog.
"These things I find are almost like time capsules. They hark back to a story. It's almost a modern form of archaeology," he told Money Box.
"You're looking at people's rubbish. You are picking up these coins and washers, tablets and ringpulls, and to me it's just fascinating. I want to know more about the people behind them. I want to know their story."
But Mr Watson has his own way of getting rid of small change free.
"I'm not paying 7.9%! I use what I call the clever man's way," he said. "Get what you want, then use the self-scan tills, feed in a handful of coins, as much as you can. Then pay the rest by card."
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