Meghan (38) and Harry (35) are still known as the Duke and Duchess of Sussex. Even after their royal exit, these titles remain with them.
In addition, the couple carry two further titles, as is customary in the British Royal Family. In Scotland they are known as Earl and Countess of Dumbarton and in Ireland they bear the names Baron and Baroness Kilkeel.
Archie Harrison can use one of his Father's Titles
Archie Harrison, however, was not given a title at birth. Although as the eldest son of the Duke of Sussex he is officially entitled to the second title of his father, Earl of Dumbarton, however at his birth Harry and Meghan let it be known that he will not use it.
He'll simply go through life as Archie Harrison Mountbatten-Windsor. Since his father officially uses the title Earl of Dumbarton in Scotland, it could theoretically be that Archie will later want to be known as Lord Kilkeel, his father's third name.
Both his parents and Archie himself will be free to choose in the future whether he will still hold the title he is entitled to. A spokesperson for Debrett's, a British professional coaching company, told the Evening Standard, "There is no reason why Archie would not inherit all his father's titles after Harry's death, but as the Sussexes have shown a degree of informality when it comes to titles, whether or not he decides to use them is to be seen."
"However, this does not stop Charles or William (once either man is king) giving Archie a title of his own when he is older, should he decide to 'work for the family firm,'" the spokesperson continued.
This is What Happens When Charles Becomes King
Archie automatically becomes the Prince of Great Britain and Northern Ireland and a Royal Highness as soon as his grandfather Prince Charles (71) becomes King. Only children and grandchildren of a monarch can hold these titles, unless the monarch awards the title personally, as was the case with the children of Prince William (37) and Duchess Kate (38).
When Prince Harry dies, Archie will inherit his three titles, as Harry received hereditary titles when he married Meghan in May 2018. However, these can only be passed on in the male line, so if Meghan and Harry have a daughter, she could not inherit any of the titles.
The Duke of Sussex Does Not Remain in the Royal House Forever
Once Prince William ascends the throne, "Duke of Sussex" will no longer be a royal title. For royal dukes, titles can only be held by direct descendants, i.e. children or grandchildren of a monarch. From then on it will be a common British title of nobility.
Should Meghan and Harry have any more children, they will not have the right to use any of the titles later, as they will only be passed on to the eldest son. Archie on the other hand may even bequeath his title later, but only to his male first-born.