The Royal Australian Mint in Canberra has unveiled the new effigy of King Charles III that will appear on $1 coins before Christmas.

Since 1953, every Australian coin has featured Queen Elizabeth II, with the late monarch's coins remaining in circulation as legal currency.

From the end of this year, coins will begin bearing the image of King Charles III, and will feature some slight differences.

As is tradition, His Majesty will be facing left — the opposite direction to his mother.

The effigy, which was designed by the Royal Mint in London and approved by Buckingham Palace, will also see the king without a crown.

This is in keeping with the first depiction of Queen Elizabeth II on Australian currency.

The mint plans to introduce 10 million King Charles III $1 coins through the banks this year before minting other coin denominations in 2024.

"The best way for you to access one of those coins … is to use cash. If you use cash, and you get change, you increase your chance of getting a coin," Royal Australian Mint chief executive Leigh Gordon said.

Queen Elizabeth II coins (and cash) to endure

The Royal Australian Mint said it would not produce commemorative coins with the image of Queen Elizabeth II from June next year.

But with a total of 15.5 billion coins featuring the longest-serving monarch minted over the course of decimal currency, Queen Elizabeth II's familiar face will endure.

"Coins have a life of 30 years, and they pop up from time to time — you can still find a 1966 coin occasionally in your change," Mr Gordon said.

Assistant Minister for Treasury Andrew Leigh was asked about the future of coins as Australians became less reliant on cash. 

"No country in the world has phased out cash, certainly its use is declining, but there are still many moments when Australians like to make use of coins," he said.

And he said there were no plans to phase out five-cent coins.

The mint confirmed it would produce five-cent coins with the king's image next year.