Queen Elizabeth: How much is the royal family actually worth?

Queen Elizabeth II

A new book has revealed just how murky the Windsor family's finances are.

Every day, The Times publishes the Court Circular, a document dating back to 1997 that lists in excruciatingly dull detail the royal family's working days.

That's how we know that on September 16 this year Princess Anne spent her day inspecting a button makers or that the Duke of Kent spent October 2 opening new school classrooms. It is an exercise in transparency that is commendable, laying bare the inner workings of the world's most famous family in all of its banal glory.

All of which stands in intriguing, glaring contrast to their approach towards money. When it comes to the Windsor clan and their finances, hard facts are hard to come by.

The Queen and her family's personal bank balances are shrouded in mystery.

In fact, answering the simple question of how much the monarch is actually worth is very, very complicated because normal rules of disclosure don't apply to the sovereign.

Now, a new book by British politician and member of the Privy Council, Norman Baker, highlights just how little is known about how the royal family achieved, and maintain, their vast personal wealth.

Princess Eugenie wore this impressive emerald tiara from the Greville haul to her wedding. Photo / Getty Images

A HUGE WINDFALL

The Queen might have had a very challenging year on a personal front, with renewed focus on Prince Andrew's connection to convicted sex offender Jeffrey Epstein and her grandchildren allegedly feuding, however 2019 will go down as a big winner financially.

Catherine, Duchess of Cambridge with Prince William, Duke of Cambridge. Photo / Getty Images

The Crown Estate owns vast tracts of the UK seabed, which are being auctioned off to create the world's biggest wind power development. The Queen and Co. are set to reap a huge windfall and by 2030 could make up to $161 million each year from this project alone, The Guardian reports.

This bonanza highlights just how extensive and varied the Windsors' investments, holdings and property are.

Which begs the question …

Prince Harry, Duke of Sussex and Meghan, Duchess of Sussex. Photo / Getty Images

THE MURKY BOTTOM LINE

Just how much money does the Queen have? Estimates vary significantly — in 2001, the Daily Mail pegged Her Majesty's fortune at about $2.3billion, excluding things owned by the Crown such as Buckingham Palace. However this year, The Times put her net worth at $708 million, making her only the 356th wealthiest person in the UK.

Don't worry, Prince George won't have to get a part-time job just yet.

Reports have suggested that the Queen also holds an investment portfolio worth up to about $1 billion. She is alleged to have one of the world's greatest stamp collections that is said to be valued at $203 million. Then there is the property — including Balmoral and Sandringham — that is owned by the Windsor family as opposed to the Crown. Those two properties alone are worth about $417 million.

MYSTERY MILLIONS

Other members of the royal family are stupendously wealthy, but Baker poses the question in his book, just how did the Queen Mother end up with a $142 million legacy? And quite how did Princess Margaret manage to build a $142 million estate when she loved to spend money?

The answer, to some degree, lies in very, very extravagant gifts.

A large part of the Queen Mother's fortune was given to her in the form of the "Greville Inheritance", a vast jewellery collection owned by Margaret Greville in 1942. When the wealthy socialite passed away, a black tin box was given to the Queen Mother containing jewellery. According to the National Trust, to this day, no one publicly knows how much jewellery was in that black box.

Princess Margaret was the recipient of a range of lavish gifts she paid no tax on. Photo / Getty Images

However, we do know the haul included a necklace that belonged to Marie Antoinette and the enormous Greville tiara that the Duchess of Cornwall regularly wears. The Duchess of Cambridge has worn the Greville ruby and diamond necklace.

Princess Margaret was also the recipient of incredibly lavish gifts. In the late 1960s Colin Tennant, Lord Glenconner, gave the royal a chunk of land on Mustique, his privately owned Caribbean island. There, she built her estate Les Jolies Eaux that her son, David Linley, sold in the late '90s for $4.9 million.

ROYAL WILL RIDDLE

When members of the royal family die, their wills are rarely if ever made public. Since 1911, a law has existed that means a will can be sealed, meaning quite how wealth is distributed in the family is a secret. Baker writes that he asked then-Prime Minister Tony Blair to make the Queen Mother's will public. He denied the request.

You will never see the Queen happier than when she is trackside. Photo / AP

What is known is that both the Queen Mother and Margaret gave away a lot of the money, jewellery, horses and art while they were still alive to escape death duties. Nearly a decade before she died, the Queen Mother had already put two thirds of her money into a trust for her grandchildren. Princes William and Harry were left a combined $28.4 million, however the majority went to Harry given Wills will inherit the $2 billion estate of the Duchy of Cornwall when he becomes the Prince of Wales.

In 1993, then-Prime Minister John Major allowed "bequests from a sovereign's consort to a sovereign and vice versa" to be exempt from inheritance taxes, according to the (UK) Telegraph, meaning that when the Queen Mother left much of her estate to her daughter, she paid no tax.

It is reported that the UK Treasury missed on making between $39 and $50 million in taxes under this arrangement.

None of this really shows the full monetary picture.

Baker reports that at the UK's National Archives in Kew, he found 3629 closed files relating to the Windsor family. Quite what these reams of documents might reveal about the finances of the Windsor family is an enigma — royal documents are excluded from Freedom of Information requests.

Kate wearing the extravagant Greville ruby and diamond necklace at a state banquet at Buckingham Palace. Photo / KensingtonRoyal, Twitter

BILLIONAIRE WILLS?

Prince Charles pulls in more than $41 million every year from the Duchy of Cornwall. That money goes to pay for his and his sons' families, including clothing and other personal expenses not covered by the Sovereign Grant.

What this means as that when Wills ascends to the title of the Prince of Wales, when Charles is crowned King, he will become stupendously wealthy. Technically, at this stage, Prince Harry will stop receiving financial support from the Duchy, leaving him to subsist on the approximately $40 million that is estimated he and wife Meghan, Duchess of Sussex, have between them.

QUEEN'S PRIVATE EMPIRE

The Duchy of Lancaster is owned by the sovereign and includes vast tracts of some of London's most valuable real estate. Currently, the Queen rakes in about $40 million in money from the Duchy that is her own money — that is, it does not have to be used to fund official travel or upkeep on Crown properties (such as Buckingham Palace).

DOES THE QUEEN EVER SPLURGE?

Yes, on something she adores — horses. It is believed that she spends millions of dollars of her own dosh on the 20 or so thoroughbred racehorses she owns.

Queen Elizabeth II with Prince Charles, Prince of Wales. Photo / Getty Images

Go on Ma'am, buy another one, you can afford it.

Daniela Elser is a royal expert and writer with more than 15 years' experience working for some of Australia' biggest media companies.