It's all-change in UK currency at the moment, what with the (non-vegan) £5 note introduced late last year and the upcoming Jane Austen £10 note. Now, our loose change is getting a makeover, too. A new-look 12-sided £1 coin will come into circulation across the country next month and we don't have much time left to spend our old ones. The old coin will still be valid when the new one is introduced on the 28th March, but will become worthless on the 15th October when it's officially phased out, The Independent reported . Shops have been told to stop accepting it from this date. The government has warned the public to ensure they spend their old pound coins or put them in the bank before they lose their status as legal tender. “Our message is clear: if you have a round one pound coin sitting at home or in your wallet, you need to spend it or return it to your bank before 15 October,” said Baroness Neville-Rolfe, commercial secretary to the Treasury. The current £1 coins could make up a third of the £1.3 billion worth of coins languishing in the nation's piggy banks and savings jars, according to a government estimate. You can exchange the old coins for notes at the bank, as long as they're in bags of 20. If you don't have enough to do this, it's worth paying them into your bank or savings account. The new coin was announced in the 2014 budget and has been described as "the most secure coin in the world" by the Royal Mint. It's supposedly more difficult for fraudsters to counterfeit because of its distinctive shape, the fact that it's made from two metals, its hologram-like image, micro-lettering and milled edges, the BBC reported . The coin even has a secret "high security feature" built into it for extra protection, the details of which haven't been revealed. Not everyone believes the new coin is worth the aggravation it'll cause for many businesses, however. "It sends a bad message about saving to the many children that will be left disappointed when they find the £1 coins they’ve squirrelled away in their piggy bank are worthless," Hannah Maundrell, editor in chief at Money.co.uk , told The Independent. "With more of us using cards and contactless payments to pay, the worth of going to all of this effort to replace what soon could be a redundant medium is questionable."