The Royal Mint announced in early 2014 that it was introducing the new coin with security features that would help stamp out fraud and counterfeiting. In 2005 notes and coins made up 64% of all payments in the United Kingdom; ten years later this had fallen to just 45%.
The round pound will still be accepted as legal tender alongside the new coin for just over six months, until October 15.
With the old pound coin set to stop being legal tender until 15 October, some businesses are struggling to adapt in time for the deadline.
Retailers are being urged to prepare for the introduction of the new £1 coin entering circulation tomorrow (28 March).
However, some older parking machines will not be able to upgrade.
Every supermarket trolley at Tesco - estimated to number hundreds of thousands - are to be unlocked after the grocery giant revealed it has not converted them all in time for the launch of the 12-sided £1 coin on Tuesday.
The coin's reverse side ("tails") features a new motif that marries symbols from the four countries comprising the United Kingdom: the English rose, the Welsh daffodil, the Scottish thistle, and the Northern Irish shamrock.
Moving onto the various security features of the new £1 coin, around the rim of the coin is an inscription that's crafted with an expensive, special laser that counterfeiters are unlikely to have access to.
However, after nearly 34 years in circulation, the current £1 coin has become increasingly vulnerable to sophisticated counterfeiters.
Until the new machines are in place auto parks will still take old £1 coins and people short of cash can pay by phone.
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They have a gold-coloured outer ring and a silver-coloured inner ring and are based on the design of the old 12-sided threepenny bit, which went out of circulation in 1971.
They're said to be the most secure coins in the world.
It will edge out the old "round pound" after more than 30 years.
There have been concerns that the new coin could present a number of teething problems for British businesses.
The UK government has reported that around £1.3 billion worth of coins are stored in savings jars across the country, and the current £1 coin accounts for almost a third of these.
What Britain's new coin bears a sparkling resemblance to as well is Singapore's own $1 coin - a similar bi-metallic version that was launched in 2013.
Joshua Best, 25, a producer from Hendon, north west London, said: "I saw the way the £5 notes got sold on eBay before so I thought "let's get this £1 coin and see what happens".
But not everyone will experience the benefits of the new £1 coin straight away as some ticket and vending machines will not immediately accept it.
About one in 30 £1 coins in circulation is a counterfeit, meaning that there are 30 million fakes out there, which if you piled up on top of each other would be 94,500 meters tall.