Meghan Markle and Prince Harry Are Using Sussex as Prince Archie and Princess Lilibet's Last Names

Meghan Markle and Prince Harry have adopted their titles as the Duke and Duchess of Sussex as the last name for their two children.

While their 4-year-old son, Prince Archie, and 2-year-old daughter, Princess Lilibet, were previously known as "Master Archie Mountbatten-Windsor" and "Miss Lilibet Mountbatten-Windsor," the children were afforded the titles of prince and princess when their grandfather King Charles became monarch in Sept. 2022.

Meghan, 42, and Prince Harry, 39, used their children's royal titles for the first time in March 2023 when they announced Lili's christening, and their names have been updated to "Prince Archie of Sussex" and "Princess Lilibet of Sussex" on the royal family's official website.

PEOPLE understands that Sussex is their family surname. Using their titles as their children's last names follows the tradition used by members of the royal family. 

Prince William and Kate Middleton's three children are officially Prince George of Wales, Princess Charlotte of Wales and Prince Louis of Wales, following their parents' titles as the Prince and Princess of Wales. However, they use a less formal version of this title at school, where they are known to their friends and teachers as George Wales, Charlotte Wales and Louis Wales.

Prince William and Prince Harry also followed this move when it came to their last name while serving in the armed forces. Instead of their royal titles, they went by "William Wales" and "Harry Wales," using their father's title at the time as the Prince of Wales for their surname.

Can't get enough of PEOPLE's Royals coverage? Sign up for our free Royals newsletter to get the latest updates on Kate Middleton, Meghan Markle and more!

Technically, the royal family’s last name is Mountbatten-Windsor. They became the House of Windsor in 1917 — previously the House of Saxe-Coburg and Gotha. The switch was prompted by anti-German feelings in the United Kingdom following World War I, so they changed the name to the more English Windsor. 

The addition of Prince Philip to the family brought about another name change, this one, the addition of Mountbatten, the last name he adopted after giving up his title of Prince of Greece and Denmark. The family explains on their website that the name Mountbatten-Windsor was officially declared in 1960, 13 years after Prince Philip married Queen Elizabeth.

"The effect of the declaration was that all The Queen's children, on occasions when they needed a surname, would have the surname Mountbatten-Windsor," they said. "For the most part, members of the Royal Family who are entitled to the style and dignity of HRH Prince or Princess do not need a surname, but if at any time any of them do need a surname (such as upon marriage), that surname is Mountbatten-Windsor."

The reignited talk about Meghan and Prince Harry's royal titles came amid the launch of their new website, Sussex.com, earlier this week.

After the couple stepped back from their roles as working members of the royal family in 2020, Buckingham Palace revealed that they would no longer use their His/Her Royal Highness titles. However, Harry and Meghan would still be referred to formally as the Duke and Duchess of Sussex and called Harry, the Duke of Sussex and Meghan, the Duchess of Sussex. Prince Harry retained his place in the line of succession to the throne. Following Queen Elizabeth's death, he holds the fifth spot after brother Prince William's three children with Princess Kate: Prince George, 10, Princess Charlotte, 8, and Prince Louis, 5.

Prince Harry and Meghan are in Canada this week for the Invictus Games Vancouver Whistler 2025's One Year to Go celebrations. The couple bundled up in winter gear for the below-freezing temperatures, holding hands as they made their way onto the snowy mountain to speak with athletes in adaptive skis and their guides.

At one point, Prince Harry got into an adaptive ski to try a run for himself.

Capturing the moment, Meghan borrowed someone's phone to snap a picture of her husband. She said she wanted to "show the kids," according to Hello! magazine reporter Rebecca Lewis.