Which source of income does the British monarch receive in addition to the Sovereign Grant?

The British monarch receives income from the Duchy of Lancaster in addition to the Sovereign Grant. The Duchy of Lancaster is a private estate owned by the reigning sovereign, which generates income through various assets, including land, property, and investments. The revenues from the Duchy are not public funds and are separate from the Sovereign Grant system, which is funded by taxpayer money and allocated to support the official duties of the monarchy.

This income plays a significant role in the financial resources available to the monarch, allowing for a level of independence from the public purse. Unlike inheritance tax revenues or private investments, which are not guaranteed sources of income for the royal family, the Duchy of Lancaster provides a steady stream of revenue, reflecting the monarch's personal estate's role in their financial matters. Other potential sources, like business profits from royal estates, do not account for the specific and well-structured income model represented by the Duchy of Lancaster, which has established precedents and legal frameworks governing its use.