Prince Harry and his wife Meghan are closing their Buckingham Palace office and will make their final appearances as full members of the Royal family at the end of March.
A spokesperson for the couple said that from April 1 the Duke and Duchess of Sussex would only be represented in the UK through their charity.
The pair sent shockwaves through the monarchy last month when they abruptly announced they would be quitting their roles as senior Royals.
Currently in North America, they will return to the UK at the end of February for a series of engagements including a music festival at Royal Albert Hall and a Commonwealth Day service at Westminster Abbey on March 9.
After the Queen gave her blessing to the couple's wish for a more independent future, the Royal family is reviewing their use of the label "Sussex Royal", the AP news agency reported.
British branding expert David Knight said the couple were becoming "just like any other members of the public" and may not be successful in their bid to own the trademark for the "Sussex Royal" name.
"They don't want to be Royal but they want to trade on the Royal name. That is a bit of an hypocrisy there, perhaps," Mr Knight told AP.
"There are clear provisions in our trademarks' law which say if it has got Royal in it, and it creates an association with the Queen and the Crown, then it's a no. You can't have that trademark unless you get the consent of the Queen or a member of the Royal family to use it."
The couple will retain their Royal Highness (HRH) titles, but they will not be used.
They will be at the Endeavour Fund awards on March 5, while Harry will visit the Silverstone motor racing circuit with Britain's Formula 1 world champion Lewis Hamilton on March 6.
Both Harry and Meghan will attend the Mountbatten Festival of Music on March 7, and Meghan will mark International Women's Day on March 8.
The following day, the couple will join the Queen and the Royal Family for the Commonwealth Service at Westminster Abbey.
Harry is also expected to be at the London Marathon in April, where he is a patron, as well as being joined by Meghan at the Invictus Games in the Netherlands in May.
After that the duke and duchess will split their time between the UK and North America, and their spokesperson said they would be in the UK "regularly".
A 12-month review undertaken following their decision to quit Royal duties is still underway, and Harry's roles will not be filled by anyone else during that time.
His honorary military positions will be suspended but he will retain his ranks of Major, Lieutenant Commander and Squadron Leader.
More details about the couple's new charitable organisation will be released later this year.
But the spokesperson said the causes they supported, including the Commonwealth, community, youth empowerment and mental health, would remain the same.
ABC/wires
