Richest monarch
Who
King Maha Vajiralongkorn
What
30,000,000,000 US dollar(s)
Where
Thailand ()
When
2018

The richest individual monarch is King Maha Vajiralongkorn (Rama X) of Thailand with an estimated personal wealth of at least $30 billion (£22.4 billion). His asset portfolio had been the property of the crown (as an institution, rather than the sovereign), but Vajiralongkorn was given control of the privy purse in 2018.