The Commonwealth Day service always takes place on the second Monday in March and is attended by heads of government and representatives of the 54 countries of the Commonwealth.
Typically, the day features a range of testimonies, readings and musical performances from talented artists across the Commonwealth and will reflect the 2020 Commonwealth theme: “Delivering A Common Future: Connecting, Innovating, Transforming”.
In recent years the Service has been broadcast live by the BBC and has attracted contributions from Ellie Goulding, Sir Richard Branson, and Nobel Peace Prize laureates, Malala Yousafzai and Kailash Satyarthi.
Tickets for the event are not available, however fans will likely be able to catch a glimpse of the Sussexes' as they arrive at the venue before the ceremony.
The occasion is the final official engagement on the list of events that Harry and Meghan pledged to undertake before they officially stand down on 31 March, with their Buckingham Palace office closing its doors on 1 April.
Before their new journey can officially begin, the couple have been required to attend multiple events over the last few months, including the Invictus Games Choir and Mountbatten Festival of Music.
Here are the final events Harry and Meghan took part in before quitting royal life.
28 February: Invictus Games Choir
The song, called "Unbroken", was created by Jon Bon Jovi to shine a spotlight on veterans living with post-traumatic stress disorder and honour their service.
The charity version of the single, featuring the Invictus Games Choir, will be released in March.
The Invictus Games Choir, which is managed and delivered by Help for Heroes, is made up of wounded, injured and sick veterans and serving personnel from all branches and different ranks of the UK Armed Forces who come together and use the power of music to aid their recovery.
The Invictus Games Foundation is the international charity that oversees the development of the Invictus Games, an international adaptive multi-sport event in which wounded, injured or sick armed services personnel and veterans participate.
Harry, who is Patron of the Invictus Games Foundation, founded the Invictus Games with the first event taking part in London in 2014. Since then, the Games have been held three other times – in Orlando (2016), Toronto (2017) and Sydney (2018). The fifth Invictus Games will take place in The Hague in May this year, followed by Düsseldorf in 2022.
5 March: Endeavour Fund Awards
For the occasion, Prince Harry opted for a blue suit and tie, while Meghan chose a simple turquoise dress with cap sleeves by Victoria Beckham, paired with navy heels.
The ceremony is an annual event that celebrates the achievements of wounded servicemen and women who have participated in sporting and adventure challenges to aid in their recovery.
Harry has appeared at every event since the launch in 2017, which he attended alongside his brother, Prince William. The Duke has also attended the ceremony with Meghan twice before, in 2018 and 2019.
Last year, the Duke and Duchess of Sussex chaired the judging panel to decide which of the nominees for each category would be announced as the winner.
Speaking of the organisation, Harry said: “You do not have to be defined by your injury or disability. It does not have to hold you back.
“You may not realise or appreciate it yet, but do not underestimate the incredible impact you are having on those around you, by simply being yourself.”
6 March: Silverstone Experience
The museum aims to tell the story of the past, present, and future of British motor racing.
In 2016, the Silverstone Heritage Experience announced that Prince Harry had been appointed as the Royal Patron of the project to create the museum.
The Silverstone UK Experience has been built inside a former Wellington bomber hangar located within the grounds of the track and officials hope it will attract more than 500,000 visitors every year.
During an event to mark the launch of the project, Harry said: “The Silverstone Experience will be an exhilarating attraction, based here at the home of British motorsport and I’m sure it will help to engage children in engineering by making that all important connection between their textbooks and the excitement and thrills of motorsport.”
7 March: Mountbatten Music Festival
The duke and duchess then received a long round of applause and a standing ovation from the audience as they took their seats in the royal box.
The event saw the Royal Marines showcase their musicianship and pageantry and featured a wide range of musical styles, including music from the big screen and solo items, as well as traditional marches and overtures.
8 March: International Women’s Day
The royal chose Dagenham because it was where female machinists at the Ford Motor Plant held a strike for equal pay in 1968, leading to the Equal Pay Act two years later.
During her speech, Meghan addressed the school’s boys in particular, urging them to “continue to value and appreciate the women in your lives and also set the example for some men who are not seeing it that same way”.
During the discussion, which was hosted by King’s College London, Meghan spoke about the importance of education and raising the next generation of feminists.
“I had seen this documentary on Netflix about feminism, and one of the things they said during pregnancy was 'I feel the embryonic kicking of feminism’,” she said.
“I loved that, so boy or girl, whatever it is, we hope that that’s the case with our little bump.”