The Consumer Council is encouraging consumers to check their homes for old round £1 coins, following the announcement that 169 million of the coins remain unreturned.
Round £1 coins were replaced by the 12-sided, two-tone version in March last year, and round coins ceased being legal tender from October 2017.
However, round coins can still be swapped at banks.
The Royal Mint has confirmed that some 169 million coins have not been returned.
Philippa McKeown-Brown, Head of Consumer Empowerment and Protection at The Consumer Council, said: “Check your piggy-banks and money jars for round £1 coins.
“Although no longer legal tender, these coins can still be exchanged at your bank for the new version.”
Specific arrangements may vary from bank to bank, including deposit limits. Customers should consult with their bank direct. Round £1 coins can also be donated to a charity. Anyone would needs more information can visit www.thenewpoundcoin.com