Duke and Duchess of Sussex have named date they will end their official duties

The Duke and Duchess of Sussex’s lives as working royals will end on 31 March when they stop representing the Queen and become financially independent, a spokeswoman for the couple has said.

Harry and Meghan will embark on a new chapter in North America, but sources have stressed they “will be in the United Kingdom regularly” and retain the same charitable goals supporting causes ranging from the Commonwealth to mental health.

The couple will attend the Commonwealth Day service at Westminster Abbey on 9 March, likely to be their last official appearance as working members of the monarchy, with the Queen and other senior royals.

The event is normally attended by the Prince of Wales, Duchess of Cornwall and Duke and Duchess of Cambridge and is a major engagement in the Queen’s calendar.

In the run-up to the service the couple will carry out a string of royal engagements before their new life in Canada begins.

Harry and Meghan will join spectators at Harry’s flagship charitable event, the Invictus Games, being staged in The Hague in the Netherlands in May, and Harry is expected to attend the London Marathon in April, in his role as patron.

The departure begins on the day the financial year traditionally ends and appears to neatly tie up their affairs, although there will be a review of arrangements after 12 months.

As they will not be working royals, their Buckingham Palace office will no longer be needed, and from 1 April they will be represented through their UK foundation team.

A source said the duke and duchess had been undertaking meetings “as part of their ongoing work to establish a new non-profit organisation. The details of this new organisation will be shared later in the year.”

Facebook Twitter Pinterest The Queen called a meeting of senior royals in the wake of Harry and Meghan’s announcement earlier in the year. Photograph: Max Mumby/Indigo/Getty Images

Harry and Meghan’s use of the word royal, as in their “Sussex Royal” branding, is being reviewed. Talks involving senior officials are ongoing about the issue and a change will be announced alongside the launch of their new organisation, said the spokeswoman.

The couple will continue to be known as the Duke and Duchess of Sussex, as well as by their titles – the Earl and Countess of Dumbarton and the Baron and Baroness Kilkeel. The spokeswoman stressed that as a grandson of the Queen and the second son of the heir to the throne, Harry remains sixth in line to the throne and the Sussexes’ status in the order of precedence is unchanged.

Harry and Meghan plunged the royal family into a period of crisis when they announced earlier in the year that they wanted to step back from their positions as senior royals and become financially independent.

A summit of senior royals was convened by the Queen at Sandringham to discuss the issue, with Harry sitting down for talks with his grandmother, father and brother.

It was later announced they would no longer be working members of the monarchy, would split their time between Canada and the UK, with the majority spent in North America, and would no longer be known as HRH. The remaining issue is how the couple will earn an income without being accused of trading on their position as members of the royal family.

Speculation is already rife the Sussexes could have received a fee worth hundreds of thousands of pounds from Harry’s recent speaking engagement at a JP Morgan-sponsored alternative investment summit in Miami, Florida.

Despite the unprecedented move the couple will keep the themes of their public work – the Commonwealth, community, youth empowerment and mental health.

The couple’s spokeswoman said Harry’s priorities remained supporting the welfare of servicemen and women, conservation, sport for social development, HIV, and Travalyst, which works to mobilise the tourism and travel industry for social good.

Meghan’s focus remains women’s empowerment, gender equality and education.