Why do Royal Family members like Princess Beatrice and Princess Eugenie not hold the title of duchess? The answer has to do with British tradition.
Royal tradition determines titles like duke and duchess
A duchy — which is held by a duke or duchess — is traditionally only given by the ruling monarch to a male successor. That is why only sons and male grandsons of the monarch are typically entitled to inherit a dukedom. A non-royal woman can share in a duchy by marrying a prince.
Queen Elizabeth II's father King George VI also bestowed the Dukedom of Edinburgh on her husband, Prince Philip, on the eve of the wedding of their 1947 wedding. Meghan Markle also became the Duchess of Sussex at her wedding to Prince Harry, Duke of Sussex, while Prince William's title—from Cambridge—was also given to Kate Middleton.
Why Eugenie and Beatrice won't become duchesses
For royals like Eugenie and Beatrice, the situation is more complicated because of this royal tradition. As women, they won't automatically inherit the Dukedom of York from their father Prince Andrew one day.
The Queen could make an exception in the case of Princess Eugenie and her sister. However, since neither of them work full-time in royal service, this is unlikely. Even after the wedding of Princess Eugenie to Jack Brooksbank in 2018, she was not made a duchess like her cousins William and Harry were made dukes for their weddings.
It was exactly the same when Princess Beatrice married Edoardo Mapelli Mozzi in 2020. Edoardo's father, however, is an Italian count, and he had confirmed to MailOnline that the princess will be entitled to the title of countess at the time of marriage. So she is also a contessa.
For more on royal titles, see how Duchess Camilla's could change when Prince Charles becomes king.