Starting March 31, or next week, Meghan Markle and Prince Harry will no longer be senior members of the royal family (open in new tab). Although they will retain their Sussex royal titles, they will lose their HRH (Her/His Royal Highness) title, and the absence of the HRH title means that Harry will take his official last name for the first time in his life. Although he took "Harry Wales" as a student, HRH title holders are not legally required to have a last name (opens in new tab) (although modern royals often use Mountbatten Windsor, a combination of the Queen and Prince Philip's name). As for Princess Meghan, she is referred to by both her maiden name (obviously Markle) and the title of Duchess of Sussex, and she can continue to use both, but would she choose to do so, especially since Archie has neither name?

The most obvious choice for the family is to collectively adopt the Mountbatten-Windsor surname, which has been in use since the 1970s. The Queen is, of course, a member of the Windsor royal family, and Prince Philip's naturalized surname (remember, he initially held both Greek and Danish royal titles) is Mountbatten. According to the Royal Family website (opens in new tab): "In most cases, members of the Royal Family with the style and dignity of the Crown Prince or Crown Princess do not require a family name, but when they do (such as at marriage), their family name is Mountbatten-Windsor."

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However, somewhat confusingly, both William and Harry took the name "Wales" in school." They were "William Wales" and "Harry Wales. (Open in new tab) Prince Charles' title is Prince of Wales, because the alternate surname for members of the royal family is often that of their parents. That tradition continues in William's family: at school, Prince George is called "George Cambridge" (open in new tab). In other words, their last name is technically Mountbatten-Windsor, and their unofficial last name is Cambridge, even though it is not strictly necessary. (Mountbatten-Windsor is quite a mouthful.)

But the plot gets complicated. When Harry and Meghan's son, Archie, was born, they did not give him a royal title-perhaps in consideration of what was about to happen (leaving the senior royal family). Mountbatten-Windsor is officially and unofficially Archie Harrison's family name. If Harry had followed in William's footsteps and strictly followed royal tradition, Archie would have assumed his title (Earl of Dumbarton) and would have been known as Archie Dumbarton. [Harry, Princess Meghan, and Archie essentially quit being senior royals and thus needed a surname. (Which means they will need a lot of paperwork for the non-profit they plan to set up. () Archie has already been decided, with Mountbatten-Windsor, after his great-grandparents. But Princess Meghan, known by her maiden name, Markle (although she has stopped calling herself "Markle (open in new tab)" since marrying Harry), is also the Duchess of Sussex (a title she will retain), so she does not have one fixed last name. She may choose to take Mountbatten, Windsor, Sussex, Markle, or a different surname altogether (which would be a break from tradition, but if she has already stepped away from the entire organization, it would not be a big problem).

In any case, "Markle" is currently different from Harry and Archie's last names, and Meghan may want to take the same last name as her family. Harry does not actually have a distinct last name right now. Technically, he is Mountbatten-Windsor, but throughout his life he has used "Wales" when he has had to use his last name. Princess Meghan could take the same surname. Sussex or Mountbatten-Windsor are the most likely options (the latter, of course, leading to Archie), but she could also choose Markle or another name entirely. After all, they are Harry and Megan.

As well as being Sussexites, the couple are also the Earl and Countess of Dumbarton and Baron and Baroness Kilkeel. They may have considered breaking away from the royal bloodline by giving their new family a new surname, but Archie's surname is already Mountbatten-Windsor, so the May choice may have been an accidental decision on their part.

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