It added that the move was “part of the adaptations carried across” since Charles acceded to the throne in 2022.
“Our aim is to explain all elements of royal finances in a way that further enhances clarity and accessibility, while also placing it in its historical and constitutional context.
“To put it simply: we continue to modernise and evolve.”
Charles’ tax information will be shared on Thursday local time as part of the release of annual royal financial accounts, the BBC reported.
Varied income
Anti-monarchy campaign group Republic called for independent authorities to audit and disclose royal tax and income, saying Charles’ voluntary disclosure decision “leaves many unanswered questions”.
“The royals can’t be allowed to self-declare their tax,” its head Graham Smith said in a statement. “They’ll spin this as Charles being a huge taxpayer, but the question is why is his income so high?”
The head of the royal family gets money from various sources, including the publicly funded Sovereign Grant as well as private duchy income worth tens of millions of pounds more.
The grant – an annual government payment to cover the costs of official duties by working royals – has increased markedly in 2025-2026, to £132.1 million ($230.1m), compared with £86.3m the previous financial year.
Charles received £26.8m in private income from the Duchy of Lancaster in 2024-25.
Profits from the historic duchy – a large, diversified portfolio of land, property, and investments managed like a modern business – funds personal expenses and some official duties.
It is the main source of private income for the head of the monarchy, with the heir – William, Prince of Wales – benefiting from a similar arrangement with his Duchy of Cornwall.
Under United Kingdom law, monarchs do not have to pay income, capital gains or inheritance taxes.
However, since 1993 they have voluntarily paid the first two, following public pressure and scrutiny of royal finances, including questions over who would pay for repairs following a fire at Windsor Castle.
Like his father, William voluntarily pays income and capital gains taxes on his duchy’s profits.
The upcoming tax disclosures will illuminate Charles’ other personal income.
The King owns both Balmoral and Sandringham Estates, which were inherited from his mother, the late Queen Elizabeth II. They were exempt from inheritance tax under a long-standing government agreement.
Other private sources of income could include money from investments or trading profits.
The royal family has sought to repair its image since damaging revelations around Andrew, Charles’ younger brother, and his ties to the late United States sex offender Jeffrey Epstein.
It has also emerged that the disgraced ex-prince earned a private income from subletting cottages while paying a symbolic “peppercorn rent” for a mansion for more than two decades.
The UK Parliament’s watchdog Public Accounts Committee has launched an inquiry into residential property arrangements provided to royals after the revelations.
– AFP