Concern is growing that many places may not yet be ready for the Royal Mint's new 12-sided pound coin, which comes into circulation tomorrow.
Commuters and travellers are likely to experience some of the biggest problems, with at least 11 transport operators including Transport for London admitting they have not yet changed all their ticket machines to accept the new coin, meaning it will be rejected when customers try to use it.
Other types of vending machines may also not be ready, with Jonathan Hart, chief executive of the Automatic Vending Association, saying that converting all 500,000 vending machines across the UK is not achievable before the new pound is released.
Shoppers will be able to use both the old and new coins in most supermarket trolleys. But Tesco announced at the end of last week that it would have to unlock the ten per cent of its trolleys which have not yet been converted to accept the coin while awaiting the installation of new locks.
The old pound coin does not cease to be legal tender until 15 October this year, so retailers and consumers alike are being given a grace period in which to make the transition.
However, a Mastercard survey conducted last year found that 87 per cent of consumers were unaware of the deadline for spending their old coins.
The treasury also released a statement last month urging UK citizens to check the back of sofas and coat pockets to retrieve the old coins before 443m of them become worthless.