The title Princess Royal is also for life, so Charlotte could only inherit it once Princess Anne has passed away, even if William becomes King before that happens.
Royal expert and author of Prince Harry: The Inside Story, Duncan Larcombe, told Town and Country: “The title of Princess Royal is traditionally bestowed on the eldest daughter of the monarch.
“It is a title that remains for life, so Princess Charlotte will have to wait at least until the death of the current Princess Royal.”
However, questions have been raised over whether Charlotte could dispense with a royal title altogether and become a “working woman” to reflect a more modern monarchy.
Former BBC royal correspondent Jennie Bond told OK! magazine: “I think we will be in a very modern era when the time comes. I question whether Charlotte will want to be burdened with more titles. She might be a working woman by then. Things could change so much in the next generation.
“The natural option it would seem to me is that she might become Princess Royal. That’s the much more traditional route that the eldest daughter becomes Princess Royal so if I was going to put money on it, it would probably be that. But I also think that she might just feel she wants to remain as just Princess Charlotte.”
Currently Charlotte’s title is HRH Princess Charlotte of Wales, and she is third in line to the throne behind William and her older brother Prince George.
As she was born after the Succession to the Crown Act 2011 came into effect, her younger brother Prince Louis did not overtake her in the line of succession, despite him being a boy.
Previously male heirs would always overtake female ones regardless of age, with Princess Anne being bumped down the line of succession after her younger brothers Prince Andrew and Prince Edward were born.