It has been nine months since the old £1 coin stopped being legal tender, but the Royal Mint reported that around 169 million of them have not yet been returned.
The round £1 coin was replaced by the 12-sided version in October 2017, with approximately 138 million of them being melted down to help create some of the 1.5 billion new ones at the Royal Mint, according to figures obtained by BBC Wales.
However, whilst the old coin cannot be spent, it can still be taken to your bank and credited to your bank account.
The new £1 coin was introduced on 28 March 2017 to help crack down on counterfeiting, with about one in 30 of the old version estimated to be fake, the Royal Mint estimated.
The Mint has described the new coin as the most “secure coin in the world” and has a series of anti-counterfeiting details, which include a hologram and micro-sized lettering inside both rims. It is also the first coin to feature material inside, which can be detected when electronically scanned by coin-counting or payment machines.
A spokesperson for the Royal Mint said that they expected about 85 per cent of the 1.7bn round £1 coins to be returned during the transition period, based on the number of coins returned when the 50p coin was replaced in 1997-98.
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