https://en.wikipedia.org/wiki/Civil_list
The abolition of the Civil List was announced in the spending review statement to the House of Commons on 20 October 2010 by the Chancellor of the Exchequer, George Osborne. In its place, he said, "the Royal Household will receive a new Sovereign Support Grant linked to a portion of the revenue of the Crown Estate". The Crown Estate is a statutory corporation, run on commercial lines by the Crown Estate Commissioners and generates revenue for HM Treasury every year (an income surplus of £210.7 million for the year ended 31 March 2010).[9] This income is received by the Crown and given to the state as a result of the agreement reached in 1760 that has been renewed at the beginning of each subsequent reign. The Sovereign Grant Act 2011 received royal assent on 18 October 2011. Under this Act, the Sovereign Grant now funds all of the official expenditure of the monarchy, not just the expenditure previously borne by the Civil List.
It appears though that this Tory change because of an inbuilt ratchet effect and its ties to the profits of the Crown Estate has become so profitable that an embarrassed King Charles has turned down a potential £250m pay rise.
https://www.theguardian.com/uk-news/2023/apr/05/how-tory-royal-funding-deal-gave-rise-to-king-charless-potential-cash-windfall
Monarch rejects £250m pay rise resulting from David Cameron’s ‘generous’ shake-up of royal funding
King Charles III’s public rejection of a pay rise potentially worth as much as £250m a year in extra taxpayer money has laid bare the extraordinarily generous funding arrangement introduced by the former prime minister David Cameron.
The sovereign grant deal, ushered in by Cameron and his chancellor, George Osborne, in 2011, has already resulted in a sharp rise in public money going to the monarchy over the last decade.
In the first financial year of the deal – 2012-13 – the budget to fund the monarchy was set at £31m. Last year, the monarch received £86.3m, including a substantial amount to refurbish Buckingham Palace. According to the terms of the sovereign grant prescribed in legislation, Charles would potentially be in line for future payments in excess of £330m a year.