The Sovereign Grant increase was sanctioned by the Royal Trustees
Royal engagements have fallen by nearly half since 2012 amid a smaller working royal team and changing priorities, even as public funding for the monarchy has more than tripled over the same period, according to official records.
Working members of the royal household carried out 2,273 duties last year, a fall from the 4,127 recorded in 2012 - the busiest year of Queen Elizabeth II's reign.
Yet the core Sovereign Grant is set to reach £100million from next year, up from £31million in 2012, equivalent to £45.8million when adjusted for inflation.
Several factors account for the diminished workload. The pool of working royals has shrunk from 15 to 11 members.
Age and health issues have also played a role, with the King having scaled back his schedule during cancer treatment.
The Prince and Princess of Wales have adopted a different approach to their duties, prioritising campaign-focused initiatives over conventional ribbon-cutting ceremonies.
William and Catherine spend around 16 weeks each year away from official duties during school holidays to be with their children, according to the Observer, contributing to fewer overall engagements.
The combination of a smaller team and changing priorities has fundamentally altered how the institution operates compared to the early 2010s.
Palace aides have previously suggested that Charles and Camilla compare favourably with the late Queen and Prince Philip at similar stages of life.
However, the King, 77, and Queen Camilla, 78, completed 708 official engagements last year.
By contrast, Queen Elizabeth II and Prince Philip managed 808 duties in 2003, when she was also 77, and he turned 82.
The late Queen and her husband were still jointly undertaking around 800 engagements as recently as 2010.
The Sovereign Grant increase was sanctioned by the Royal Trustees, comprising Prime Minister Sir Keir Starmer, Chancellor Rachel Reeves and the King's Keeper of the Privy Purse James Chalmers.
From 2027, the King plans to allocate £25million annually from public funds towards repairs and renovations across royal residences.
The spending will cover properties across the occupied royal palaces estate, which comprises 255 buildings, including eight currently vacant homes.
Royal household officials are hoping to generate additional revenue by letting out more of these properties, supplementing the £3.9million the monarch already receives in rental income each year.
The rental income would supplement the Sovereign Grant as the Royal Household seeks new ways to fund the upkeep of its extensive property portfolio.