King Charles faces growing calls to refund millions to the NHS following revelations that his private estate, the Duchy of Lancaster, is charging one London NHS trust £11.4 million in rent over a 15-year lease to store a fleet of electric ambulances.

An investigation revealed that the private estates of King Charles and Prince William generate substantial income from the NHS, the Armed Forces, and various charities.

Land and property owned by the Duchies of Lancaster and Cornwall are also leased to schools, mining companies, and major corporations, among others.

The inquiry uncovered that the Duchy of Lancaster, acting on behalf of the King, has entered into an agreement with a London trust that will require the NHS to pay over £11 million over 15 years for the privilege of parking ambulances in one of its warehouses.

Mail Online reports that documents reveal the Duchy of Cornwall earns £830,000 annually from leasing a two-storey warehouse to Guy’s and St Thomas’ NHS Foundation Trust in London.

Dennis Reed of the elderly advocacy group Silver Voices, criticised the arrangement, saying, “It is disgraceful, especially considering the pressure on the NHS, for the Royal Family to charge fees for ambulance parking and other NHS uses.”

An investigation by Channel 4’s Dispatches and The Sunday Times explored land and property assets owned by senior royals through the duchies.

The investigation identified 5,410 assets—including landholdings, mineral rights, and properties—held by the Duchy of Lancaster on behalf of the King, and the Duchy of Cornwall for the Prince of Wales.

It found that the duchies charge for a range of activities on these lands, including crossing rivers, dumping waste, unloading cargo, running cables, operating lifeboats, and even digging graves.

The Duchy of Cornwall also collects rent from Dartmoor Prison, with the Ministry of Justice paying £37.5 million. Charities, including Macmillan Cancer Support and Marie Curie Cancer Care—both of which have Charles as a patron—have reportedly paid millions to rent a 1960s office building in London.

However, the investigation noted that some private residential properties leased by both duchies fail to meet minimum energy efficiency standards.

A spokesman for the Duchy of Lancaster stated that the portfolio’s day-to-day management is handled by the Council and executive team.