What's more, the Duke of Cambridge will inherit Prince Charles' $1.8 billion Duchy of Cornwall estate with the new role.
The Court Circular (the official diary of the royal family) shows that Prince William has been in special meetings about the estate.
The diary reads on September 12:
"The Duke of Cambridge this morning attended a Duchy of Cornwall Meeting at 10 Buckingham Gate, London SW1."
The father-of-three has reportedly already attended three of these meetings this year.
"In the not-too-distant future we will witness the dawn of a new sovereignty and the newly crowned King Charles III will be flanked by sons who love and respect him," Victoria Arbiter wrote for 9Honey.
"I dare say there's no-one he would rather be supported by as he prepares to embark on his most challenging role to date."
According to Cornwall Live, the Duchy of Cornwall estate includes the Isles of Schilly, the Truro Eastern District Centre, the Duchy of Cornwall Nursery, 900 hectares of woodland (including Greenscombe Wood in the Tamar Valley) and stretches of water such as the Looe, Helford, and Camel estuaries.
9 Honey reports that the money generated from the estate will fund the Duke and Duchess of Cambridge's expenses, as well as the expenses of other members of the royal family.
Presently, Prince Charles uses the money from the Cornwall Estate to fund Prince William and Kate Middleton (and their children, Prince George, Princess Charlotte, Prince Louis), Prince Harry and Meghan Markle (and their son, Archie-Harrison).