King Charles will become the first head of state to reveal their personal tax bill in what the palace said was an attempt to enhance the transparency of royal finances.

Charles, 77, will publish his financial details as part of the royal household increasing the “clarity and accessibility” of the monarchy’s finances by producing a new report on the subject.

The king’s total personal tax information for the 2024-25 financial year will be published next week alongside other financial reports. His 2025-26 tax details will be released next year when the audit has been completed.

The decision by the king, who has spent the week at Royal Ascot in Berkshire, is in contrast to his son, the Prince of Wales, 43, who has not disclosed the tax he has paid since becoming heir to the throne.

A Buckingham Palace spokesperson said: “While this is the first time a monarch has shared this personal tax information, you may recall it was similarly released by His Majesty when he was Prince of Wales.

“The decision to do so as sovereign has come at the express wish of the king himself, as part of the adaptations carried across since accession.”

The king’s private sources of income could include money from investments or trading profits, funds generated by his private estates of Balmoral and Sandringham and private savings.

The Duchy of Lancaster estate, a private portfolio of land, investments and office, retail and industrial property, also provides the king with an annual income which in 2024-25 was £26.8m.

Charles voluntarily pays income tax on all his private income, and capital gains tax on relevant elements of his assets, as laid out in the Memorandum of Understanding on Royal Taxation 2023, agreed by the government.

William receives an income from the Duchy of Cornwall, a billion-pound hereditary estate featuring The Oval cricket ground and Dartmoor prison, providing the heir to the throne with funds independent of the monarch.

The prince received nearly £23m in the last financial year from the duchy and voluntarily pays the highest rate of income tax, once official costs have been deducted but the amount he pays in tax is not disclosed.

Accounts detailing the sovereign grant, which funds the official duties of the royal family, will be published at a press briefing next week alongside a separate extensive new royal household report on the monarch’s finances.

A Buckingham Palace spokesperson said: “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.”

Alongside the new publication and the sovereign grant report, the Duchy of Lancaster’s accounts will also be published at another press briefing.

A Buckingham Palace spokesperson said about the changes: “In order to constantly improve, and to encourage wider understanding of our accountability, the royal household has been considering options to enhance this transparency still further – and can today announce additional measures in keeping with our public service priorities.

“To put it simply: we continue to modernise and evolve.”