What will Princess Kate be called when Prince William is King?

Kate Middleton and Prince William at National Service of Thanksgiving

When the Prince of Wales takes over the throne from his father King Charles, he will likely be styled as King William V. But there has been confusion as to how his wife Kate will be known, with some reporting that she will be Queen Catherine VI.

When HELLO! spoke to royal historian Marlene Koenig, the founder of Royal Musings blog, she confirmed that Kate will simply be styled as Queen Catherine. Kate will indeed be the sixth woman with a variant of the name Catherine to be a consort but she will not have a regnal number; only the sovereign and not his or her consort has a number after their name.

Here's all you need to know about the Princess of Wales' future royal title...

How Kate's title has changed since the late Queen's death

Kate Middleton with a group of Welsh schoolchildren
Kate is currently the Princess of Wales (Karwai Tang)

When King Charles ascended to the throne, William was granted many of his old titles including the Duke of Cornwall and the Prince of Wales. Kate also picked up these titles as well and is known as the Princess of Wales and Duchess of Cornwall. When the royal mum-of-three is in Scotland, she is known as the Duchess of Rothesay.

What will happen when William becomes King?

As we explained, when William becomes King, Kate will become his Queen Consort and will be known as Queen Catherine. As she is not a regnant, Kate will not have a number after her name.

More on the Princess of Wales

Despitethe late Queen's husband, Prince Philip being known as the Queen's consort, Kate will not be a Princess consort. "The wife of the king is by tradition a queen," said Marlene.

Kate Middleton and Prince William on the Buckingham Palace balcony
Kate's title will change when William becomes King (Pool)

But then why is Prince Philip, the Queen's consort, known as a Prince and not a King? Marlene explained: "The husband of a queen, in most monarchies, has to be created a title. A husband does not share a wife's rank and the same goes for the husbands of Princesses." This explains why Princess Eugenie's husband Jack Brooksbank wasn't given a new title upon their marriage.

Marlene added: "Philip was not created a Prince of the UK until 1957. He was given the UK HRH and the titles Duke of Edinburgh, Earl of Merioneth and Baron Greenwich by George VI before the wedding, but was not created a British Prince until nearly ten years later." Historian Tim Heald's view is that Philip was given the title Prince as a reward for ten years of marriage.

What will happen when William dies?

Kate Middleton at the late Queen's funeral
Kate will likely become the Queen Mother if William dies before her (Samir Hussein)

Kate's title is due to change again if she outlives her husband. If William dies before his wife, then Kate will likely become known as the Queen Mother, provided that one of their children, Prince George, Princess Charlotte or Prince Louis succeeds their father to the throne. In the unlikely event a different royal accedes to the throne, then Kate will be the 'queen dowager', otherwise known as the widow of a King.

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