With the passing of Queen Elizabeth II, many people wonder what will happen to Commonwealth banknotes and coins, which have bared the monarch's likeness for much of her 70-year reign.

The Queen's image can be found on the currency of more than 15 countries, the most populated being the United Kingdom, Australia, Canada and New Zealand. This list includes Bermuda, St. Lucia and Montserrat, along with other Caribbean nations that use the Eastern Caribbean dollar. Currency in many Oceania countries also bears the Queen's portrait.

Tradition suggests that King Charles III will replace the Queen's effigy on these countries' currencies, although it has not been announced in most countries yet.

In some cases, images of the monarch could be replaced by something else, as some Commonwealth countries have done in recent years, like Jamaica and the small African nation of Seychelles.

Here's a look at known changes in the four biggest countries with British monarchs on their currency.

United Kingdom

The Queen's image has been on Commonwealth currency so long that there was apparently some confusion as to whether the money was still valid after her death. 

A statement from the Bank of England this week clarified that the "Queen will continue to be legal tender" in the United Kingdom, as is the case with other nations.

A portrait of King Charles III is expected to replace the Queen on U.K. currency, with more details to be provided after the Queen's funeral, according to the central bank's press release.

There are 4.5 billion sterling bank notes in circulation, so replacing them with updated King Charles III currency will likely take about two years, according to The Guardian.

Australia

The Royal Australian Mint confirmed Tuesday that it will start minting coins with the effigy of King Charles III next year.

Currently, the country's $5 bill features the Queen's portrait and remains legal tender. The image will change, although there's no guarantee that the portrait of King Charles III will be used, according to Australia's Assistant Minister for Treasury Andrew Leigh.

When asked about replacing monarchs on $5 banknote with First Nation activists like Eddie Mabo or Vincent Lingiari, Leigh acknowledged that it was a possibility. But either way, the current $5 bill will not be withdrawn and stay in circulation "for years to come," according to a Reserve Bank of Australia statement.

Canada

In Canada, the Queen's image is featured on its coins and plastic $20 banknotes. The Department of Finance, which has final say on design changes, hasn't announced any plans for what will replace the Queen's image.

The Royal Canadian Mint has issued a statement noting that "a change in Monarch does not require the replacement of circulation coins."   

There has been some social media chatter about replacing portraits of monarchs with new designs. An opinion poll conducted days after the Queen's death by Pollara Strategic Insights found that 56% of Canadians would oppose using the face of King Charles III on currency.

New Zealand

King Charles III will replace the Queen's image on all of New Zealand's coins, as well as its $20 banknotes.

However, for cost reasons, there are no immediate changes planned as any new design is "a few years away," according to a Reserve Bank of New Zealand statement. 

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