That title belongs to King Felipe VI of Spain. Last year, he revealed a full breakdown of all his wealth as a way of being transparent with the public.
From this report, it was revealed that his net worth amounted to €2.57 million (~$2.8 million), which is quite low for a reigning monarch. In fact, it's not even enough to break through the top 100 wealthiest in Spain. Most of this wealth comes from bank deposits and investment funds along with jewellery, antiques, and works of art, since the Spanish monarch has no land or properties to his name.
Apparently, his bank accounts, amounting to €2.26 million, make up almost 90% of his wealth, with the remaining €300,000 from collectors' items and jewellery. Sadly, Felipe VI has no pension plan either.
In comparison, the late Queen Elizabeth II in 2022 had a net worth of about €444 million (~$490 million). But the former British monarch was not even the richest among the European royals. That would be the grand duke of Luxembourg, Henri, whose family's estate was roughly €3.75 billion (~$4.1 billion). Closely following him is Prince Hans Adam II of Liechtenstein, with an estimated net worth of €3.3 billion (~$3.6 billion).
Around the world, the title of the richest royal belongs to King Rama X, the Thai king with a net worth valued at €27 billion (~$29.8 billion). After him is Sultan Hassanal Bolkiah of Brunei with €18 billion (~$19.8 billion), then King Salman bin Abdulaziz Al-Saud of Saudi Arabia with €16 billion (~$17.6 billion).
Note: Figures were from 2022.
(Image credit: Vox Congreso/Wikimedia Commons)