
Since becoming part of the royal family 14 years ago, Kate Middleton has taken on a range of titles — but one change in particular marked a historic shift for the monarchy.
On her wedding day, Kate was officially given the title Duchess of Cambridge. It was a wedding gift from Queen Elizabeth II to both her and Prince William, who became the Duke of Cambridge. Along with the duchess title, Kate was also named Countess of Strathearn and Baroness Carrickfergus, and gained the honorific style of Her Royal Highness.
Although she technically became a princess through her marriage to Prince William and could have gone by “Princess William,” she chose to use the duchess title instead.

Becoming the Princess of Wales
When King Charles III ascended the throne following the death of Queen Elizabeth II, William inherited the title Prince of Wales. This meant Kate’s title changed from Duchess of Cambridge to Princess of Wales — the same title once held by William’s late mother, Princess Diana.
Looking ahead, when William becomes king, he could choose to reign under the name King William, and Kate would then be known as Queen Catherine.
Because Kate doesn’t have royal blood, she won’t be known as a reigning queen. Instead, she will hold the title of Queen Consort — much like Queen Camilla. However, in everyday use, it’s likely she’ll simply be called Queen Catherine, following the informal precedent set with Camilla.

Additional Titles Across the UK
Kate has also gained other titles depending on her location within the UK. She is:
Duchess of Cornwall (a title formerly held by Camilla)
Countess of Chester
Duchess of Rothesay when in Scotland
Countess of Carrick and Baroness of Renfrew when in Northern Ireland
And Lady of the Isles
Military Titles and Patronages
In addition to her royal titles, Kate holds several honorary positions in the military, including: