It is currently unknown whether the couple will take a last name after giving up their HRH titles. There is a case to be made for taking the name Wales , as Prince Harry was called Captain Harry Wales in the British Army. They may be known as the Sussexes, given that the Queen referred to them in her statement as “Harry and Meghan” and Buckingham Palace’s official statement referred to them as the Sussexes. The Sussex name is also prominent on baby Archie’s birth certificate , where Prince Harry’s full name is listed as His Royal Highness Henry Charles Albert David Duke of Sussex. The couple could also take the surname Mountbatten-Windsor , as Windsor was officially adopted as the surname for the family in 1917 and Mountbatten-Windsor given as the specific distinction for direct descendants of the Queen and Prince Phillip, Duke of Edinburgh. They could also come up with something completely different, like when Princess Eugenie took on the title Mrs. Jack Brooksbank after her wedding. Prince Harry, Mr. Meghan Markle, anyone? If in doubt, however, you can still call them Prince Harry and Meghan, the Duke and Duchess of Sussex.